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[
"Characteristics",
"Anura"
] | The order [[Anura (frog)|Anura]] (from the Ancient Greek ''[[Privative a|a(n)-]]'' meaning "without" and ''oura'' meaning "tail") comprises the frogs and toads. They usually have long hind limbs that fold underneath them, shorter forelimbs, webbed toes with no claws, no tails, large eyes and glandular moist skin. Members of this order with smooth skins are commonly referred to as frogs, while those with [[wikt:warty|warty]] skins are known as toads. The difference is not a formal one taxonomically and there are numerous exceptions to this rule. Members of the family [[Bufonidae]] are known as the "true toads". Frogs range in size from the [[Goliath frog]] (''Conraua goliath'') of West Africa to the ''[[Paedophryne amauensis]]'', first described in Papua New Guinea in 2012, which is also the smallest known vertebrate. Although most species are associated with water and damp habitats, some are specialised to live in trees or in deserts. They are found worldwide except for polar areas. Anura is divided into three suborders that are broadly accepted by the scientific community, but the relationships between some families remain unclear. Future [[molecular genetics|molecular]] studies should provide further insights into their evolutionary relationships. The suborder [[Archaeobatrachia]] contains four families of primitive frogs. These are [[Ascaphidae]], [[Bombinatoridae]], [[Discoglossidae]] and [[Leiopelmatidae]] which have few derived features and are probably paraphyletic with regard to other frog lineages. The six families in the more evolutionarily advanced suborder [[Mesobatrachia]] are the [[fossorial]] [[Megophryidae]], [[Pelobatidae]], [[Pelodytidae]], [[Scaphiopodidae]] and [[Rhinophrynidae]] and the obligatorily aquatic [[Pipidae]]. These have certain characteristics that are intermediate between the two other suborders. [[Neobatrachia]] is by far the largest suborder and includes the remaining families of modern frogs, including most common species. Ninety-six percent of the over 5,000 extant species of frog are neobatrachians. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Characteristics",
"Caudata"
] | The order [[Caudata]] (from the Latin ''cauda'' meaning "tail") consists of the salamanders—elongated, low-slung animals that mostly resemble lizards in form. This is a [[Symplesiomorphy|symplesiomorphic trait]] and they are no more closely related to lizards than they are to mammals. Salamanders lack claws, have scale-free skins, either smooth or covered with [[tubercle]], and tails that are usually flattened from side to side and often finned. They range in size from the [[Chinese giant salamander]] (''Andrias davidianus''), which has been reported to grow to a length of , to the diminutive ''[[Thorius pennatulus]]'' from Mexico which seldom exceeds in length. Salamanders have a mostly [[Laurasia]] distribution, being present in much of the [[Holarctic]] region of the northern hemisphere. The family [[Plethodontidae]] is also found in Central America and South America north of the [[Amazon basin]]; South America was apparently invaded from Central America by about the start of the [[Miocene]], 23 million years ago. Urodela is a name sometimes used for all the [[extant taxon|extant]] species of salamanders. Members of several salamander families have become [[Neoteny|paedomorphic]] and either fail to complete their metamorphosis or retain some larval characteristics as adults. Most salamanders are under long. They may be terrestrial or aquatic and many spend part of the year in each habitat. When on land, they mostly spend the day hidden under stones or logs or in dense vegetation, emerging in the evening and night to forage for worms, insects and other invertebrates. The suborder [[Cryptobranchoidea]] contains the primitive salamanders. A number of fossil cryptobranchids have been found, but there are only three living species, the Chinese giant salamander (''Andrias davidianus''), the [[Japanese giant salamander]] (''Andrias japonicus'') and the [[hellbender]] (''Cryptobranchus alleganiensis'') from North America. These large amphibians retain several larval characteristics in their adult state; gills slits are present and the eyes are unlidded. A unique feature is their ability to feed by suction, depressing either the left side of their lower jaw or the right. The males excavate nests, persuade females to lay their egg strings inside them, and guard them. As well as breathing with lungs, they respire through the many folds in their thin skin, which has [[Capillary|capillaries]] close to the surface. The suborder [[Salamandroidea]] contains the advanced salamanders. They differ from the cryptobranchids by having fused [[Mandible|prearticular bones]] in the lower jaw, and by using internal fertilisation. In salamandrids, the male deposits a bundle of sperm, the [[spermatophore]], and the female picks it up and inserts it into her cloaca where the sperm is stored until the eggs are laid. The largest family in this group is Plethodontidae, the lungless salamanders, which includes 60% of all salamander species. The [[Family (biology)|family]] [[Salamandridae]] includes the true salamanders and the name "[[newt]]" is given to members of its subfamily [[Pleurodelinae]]. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Characteristics",
"Caudata"
] | The third suborder, [[Sirenoidea]], contains the four species of sirens, which are in a single family, [[Sirenidae]]. Members of this order are [[eel]]-like aquatic salamanders with much reduced forelimbs and no hind limbs. Some of their features are primitive while others are derived. Fertilisation is likely to be external as sirenids lack the cloacal glands used by male salamandrids to produce spermatophores and the females lack [[spermatheca]] for sperm storage. Despite this, the eggs are laid singly, a behaviour not conducive for external fertilisation. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Characteristics",
"Gymnophiona"
] | The order [[Gymnophiona]] (from the Greek ''gymnos'' meaning "naked" and ''ophis'' meaning "serpent") or Apoda comprises the caecilians. These are long, cylindrical, limbless animals with a snake- or [[Annelid|worm-like]] form. The adults vary in length from 8 to 75 centimetres (3 to 30 inches) with the exception of [[Caecilia thompsoni|Thomson's caecilian]] (''Caecilia thompsoni''), which can reach . A caecilian's skin has a large number of transverse folds and in some species contains tiny embedded dermal scales. It has rudimentary eyes covered in skin, which are probably limited to discerning differences in light intensity. It also has a pair of short [[tentacle]] near the eye that can be extended and which have [[Somatosensory system|tactile]] and [[Olfaction|olfactory]] functions. Most caecilians live underground in burrows in damp soil, in rotten wood and under plant debris, but some are aquatic. Most species lay their eggs underground and when the larvae hatch, they make their way to adjacent bodies of water. Others brood their eggs and the larvae undergo metamorphosis before the eggs hatch. A few species give birth to live young, nourishing them with glandular secretions while they are in the oviduct. Caecilians have a mostly [[Gondwana]] distribution, being found in tropical regions of Africa, Asia and Central and South America. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Anatomy and physiology",
"Skin"
] | The [[Wikt:integument|integumentary]] structure contains some typical characteristics common to terrestrial vertebrates, such as the presence of highly [[Keratin#Cornification|cornified]] outer layers, renewed periodically through a moulting process controlled by the [[pituitary gland|pituitary]] and [[thyroid]] glands. Local thickenings (often called warts) are common, such as those found on toads. The outside of the skin is shed periodically mostly in one piece, in contrast to mammals and birds where it is shed in flakes. Amphibians often eat the sloughed skin. Caecilians are unique among amphibians in having mineralized dermal scales embedded in the [[dermis]] between the furrows in the skin. The similarity of these to the scales of bony fish is largely superficial. [[Squamata|Lizards]] and some frogs have somewhat similar [[osteoderm]] forming bony deposits in the dermis, but this is an example of [[convergent evolution]] with similar structures having arisen independently in diverse vertebrate lineages. Amphibian skin is permeable to water. Gas exchange can take place through the skin ([[cutaneous respiration]]) and this allows adult amphibians to respire without rising to the surface of water and to hibernate at the bottom of ponds. To compensate for their thin and delicate skin, amphibians have evolved mucous glands, principally on their heads, backs and tails. The secretions produced by these help keep the skin moist. In addition, most species of amphibian have granular glands that secrete distasteful or poisonous substances. Some amphibian toxins can be lethal to humans while others have little effect. The main poison-producing glands, the [[Parotoid gland|parotoids]], produce the neurotoxin [[bufotoxin]] and are located behind the ears of toads, along the backs of frogs, behind the eyes of salamanders and on the upper surface of caecilians. The skin colour of amphibians is produced by three layers of pigment cells called [[chromatophore]]. These three cell layers consist of the melanophores (occupying the deepest layer), the guanophores (forming an intermediate layer and containing many granules, producing a blue-green colour) and the lipophores (yellow, the most superficial layer). The colour change displayed by many species is initiated by [[hormone]] secreted by the pituitary gland. Unlike bony fish, there is no direct control of the pigment cells by the nervous system, and this results in the colour change taking place more slowly than happens in fish. A vividly coloured skin usually indicates that the species is toxic and is a warning sign to predators. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Anatomy and physiology",
"Skeletal system and locomotion"
] | Amphibians have a skeletal system that is structurally [[Homology (biology)|homologous]] to other tetrapods, though with a number of variations. They all have four limbs except for the legless caecilians and a few species of salamander with reduced or no limbs. The bones are hollow and lightweight. The musculoskeletal system is strong to enable it to support the head and body. The bones are fully [[ossification|ossified]] and the vertebrae interlock with each other by means of overlapping processes. The [[pectoral girdle]] is supported by muscle, and the well-developed [[pelvic girdle]] is attached to the backbone by a pair of sacral ribs. The [[ilium (bone)|ilium]] slopes forward and the body is held closer to the ground than is the case in mammals. In most amphibians, there are four digits on the fore foot and five on the hind foot, but no claws on either. Some salamanders have fewer digits and the [[amphiuma]] are eel-like in appearance with tiny, stubby legs. The [[Siren (genus)|sirens]] are aquatic salamanders with stumpy forelimbs and no hind limbs. The caecilians are limbless. They burrow in the manner of earthworms with zones of muscle contractions moving along the body. On the surface of the ground or in water they move by undulating their body from side to side. In frogs, the hind legs are larger than the fore legs, especially so in those species that principally move by jumping or swimming. In the walkers and runners the hind limbs are not so large, and the burrowers mostly have short limbs and broad bodies. The feet have adaptations for the way of life, with webbing between the toes for swimming, broad adhesive toe pads for climbing, and keratinised tubercles on the hind feet for digging (frogs usually dig backwards into the soil). In most salamanders, the limbs are short and more or less the same length and project at right angles from the body. Locomotion on land is by walking and the tail often swings from side to side or is used as a prop, particularly when climbing. In their normal gait, only one leg is advanced at a time in the manner adopted by their ancestors, the lobe-finned fish. Some salamanders in the genus ''[[Aneides]]'' and certain [[lungless salamander|plethodontids]] climb trees and have long limbs, large toepads and prehensile tails. In aquatic salamanders and in frog tadpoles, the tail has [[dorsal fin|dorsal]] and [[ventral fin|ventral]] fins and is moved from side to side as a means of propulsion. Adult frogs do not have tails and caecilians have only very short ones. Salamanders use their tails in defence and some are prepared to jettison them to save their lives in a process known as [[autotomy]]. Certain species in the Plethodontidae have a weak zone at the base of the tail and use this strategy readily. The tail often continues to twitch after separation which may distract the attacker and allow the salamander to escape. Both tails and limbs can be regenerated. Adult frogs are unable to regrow limbs but tadpoles can do so. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Anatomy and physiology",
"Circulatory system"
] | Amphibians have a juvenile stage and an adult stage, and the circulatory systems of the two are distinct. In the juvenile (or tadpole) stage, the circulation is similar to that of a fish; the two-chambered heart pumps the blood through the gills where it is oxygenated, and is spread around the body and back to the heart in a single loop. In the adult stage, amphibians (especially frogs) lose their gills and develop lungs. They have a heart that consists of a single ventricle and two atria. When the ventricle starts contracting, deoxygenated blood is pumped through the [[pulmonary artery]] to the lungs. Continued contraction then pumps oxygenated blood around the rest of the body. Mixing of the two bloodstreams is minimized by the anatomy of the chambers. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Anatomy and physiology",
"Nervous and sensory systems"
] | The [[nervous system]] is basically the same as in other vertebrates, with a central brain, a spinal cord, and nerves throughout the body. The amphibian brain is less well developed than that of reptiles, birds and mammals but is similar in morphology and function to that of a fish. It is believed amphibians are capable of perceiving [[Pain in amphibians|pain]]. The brain consists of equal parts, [[cerebrum]], [[midbrain]] and [[cerebellum]]. Various parts of the cerebrum process sensory input, such as smell in the olfactory lobe and sight in the optic lobe, and it is additionally the centre of behaviour and learning. The cerebellum is the center of muscular coordination and the [[medulla oblongata]] controls some organ functions including heartbeat and respiration. The brain sends signals through the spinal cord and nerves to regulate activity in the rest of the body. The [[pineal body]], known to regulate sleep patterns in humans, is thought to produce the hormones involved in [[hibernation]] and [[aestivation]] in amphibians. Tadpoles retain the lateral line system of their ancestral fishes, but this is lost in terrestrial adult amphibians. Some caecilians possess [[Electroreception|electroreceptors]] that allow them to locate objects around them when submerged in water. The ears are well developed in frogs. There is no external ear, but the large circular [[Tympanum (anatomy)|eardrum]] lies on the surface of the head just behind the eye. This vibrates and sound is transmitted through a single bone, the [[stapes]], to the inner ear. Only high-frequency sounds like mating calls are heard in this way, but low-frequency noises can be detected through another mechanism. There is a patch of specialized haircells, called ''papilla amphibiorum'', in the inner ear capable of detecting deeper sounds. Another feature, unique to frogs and salamanders, is the columella-operculum complex adjoining the auditory capsule which is involved in the transmission of both airborne and seismic signals. The ears of salamanders and caecilians are less highly developed than those of frogs as they do not normally communicate with each other through the medium of sound. The eyes of tadpoles lack lids, but at metamorphosis, the [[cornea]] becomes more dome-shaped, the [[Lens (anatomy)|lens]] becomes flatter, and [[eyelid]] and associated glands and ducts develop. The adult eyes are an improvement on invertebrate eyes and were a first step in the development of more advanced vertebrate eyes. They allow colour vision and depth of focus. In the retinas are green rods, which are receptive to a wide range of wavelengths. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Anatomy and physiology",
"Digestive and excretory systems"
] | Many amphibians catch their prey by flicking out an elongated tongue with a sticky tip and drawing it back into the mouth before seizing the item with their jaws. Some use inertial feeding to help them swallow the prey, repeatedly thrusting their head forward sharply causing the food to move backwards in their mouth by [[inertia]]. Most amphibians swallow their prey whole without much chewing so they possess voluminous stomachs. The short [[Esophagus|oesophagus]] is lined with [[Cilium|cilia]] that help to move the food to the stomach and [[mucus]] produced by glands in the mouth and [[pharynx]] eases its passage. The enzyme [[chitinase]] produced in the stomach helps digest the [[chitin]] cuticle of arthropod prey. Amphibians possess a [[pancreas]], [[liver]] and [[gall bladder]]. The liver is usually large with two lobes. Its size is determined by its function as a [[glycogen]] and fat storage unit, and may change with the seasons as these reserves are built or used up. [[Adipose tissue]] is another important means of storing energy and this occurs in the abdomen (in internal structures called fat bodies), under the skin and, in some salamanders, in the tail. There are two [[kidney]] located dorsally, near the roof of the body cavity. Their job is to filter the blood of metabolic waste and transport the urine via ureters to the urinary bladder where it is stored before being passed out periodically through the cloacal vent. Larvae and most aquatic adult amphibians excrete the nitrogen as ammonia in large quantities of dilute urine, while terrestrial species, with a greater need to conserve water, excrete the less toxic product urea. Some tree frogs with limited access to water excrete most of their metabolic waste as uric acid. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Anatomy and physiology",
"Respiratory system"
] | The lungs in amphibians are primitive compared to those of amniotes, possessing few internal [[alveolar septum|septa]] and large [[Pulmonary alveolus|alveoli]], and consequently having a comparatively slow diffusion rate for oxygen entering the blood. Ventilation is accomplished by [[buccal pumping]]. Most amphibians, however, are able to exchange gases with the water or air via their skin. To enable sufficient [[cutaneous respiration]], the surface of their highly vascularised skin must remain moist to allow the oxygen to diffuse at a sufficiently high rate. Because oxygen concentration in the water increases at both low temperatures and high flow rates, aquatic amphibians in these situations can rely primarily on cutaneous respiration, as in the [[Telmatobius culeus|Titicaca water frog]] and the [[Cryptobranchus|hellbender salamander]]. In air, where oxygen is more concentrated, some small species can rely solely on cutaneous gas exchange, most famously the [[Plethodontidae|plethodontid salamanders]], which have neither lungs nor gills. Many aquatic salamanders and all tadpoles have gills in their larval stage, with some (such as the [[axolotl]]) retaining gills as aquatic adults. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Reproduction"
] | For the purpose of [[Biological reproduction|reproduction]] most amphibians require [[fresh water]] although some lay their eggs on land and have developed various means of keeping them moist. A few (e.g. ''[[Fejervarya raja]]'') can inhabit brackish water, but there are no true [[marine (ocean)|marine]] amphibians. There are reports, however, of particular amphibian populations unexpectedly invading marine waters. Such was the case with the [[Black Sea]] invasion of the natural hybrid ''[[Pelophylax esculentus]]'' reported in 2010. Several hundred frog species in [[adaptive radiation]] (e.g., ''[[Eleutherodactylus]]'', the Pacific ''[[Platymantis]]'', the Australo-Papuan [[microhylid]], and many other tropical frogs), however, do not need any water for [[breeding in the wild]]. They reproduce via direct development, an ecological and evolutionary adaptation that has allowed them to be completely independent from free-standing water. Almost all of these frogs live in wet [[Tropical and subtropical moist broadleaf forests|tropical rainforests]] and their eggs hatch directly into miniature versions of the adult, passing through the [[tadpole]] stage within the egg. Reproductive success of many amphibians is dependent not only on the quantity of rainfall, but the seasonal timing. In the tropics, many amphibians breed continuously or at any time of year. In temperate regions, breeding is mostly seasonal, usually in the spring, and is triggered by increasing day length, rising temperatures or rainfall. Experiments have shown the importance of temperature, but the trigger event, especially in arid regions, is often a storm. In anurans, males usually arrive at the breeding sites before females and the vocal chorus they produce may stimulate ovulation in females and the endocrine activity of males that are not yet reproductively active. In caecilians, fertilisation is internal, the male extruding an [[intromittent organ]], the , and inserting it into the female cloaca. The paired Müllerian glands inside the male cloaca secrete a fluid which resembles that produced by mammalian [[prostate]] glands and which may transport and nourish the sperm. Fertilisation probably takes place in the oviduct. The majority of salamanders also engage in [[internal fertilisation]]. In most of these, the male deposits a spermatophore, a small packet of sperm on top of a gelatinous cone, on the [[Substrate (biology)|substrate]] either on land or in the water. The female takes up the sperm packet by grasping it with the lips of the cloaca and pushing it into the vent. The spermatozoa move to the spermatheca in the roof of the cloaca where they remain until ovulation which may be many months later. Courtship rituals and methods of transfer of the spermatophore vary between species. In some, the spermatophore may be placed directly into the female cloaca while in others, the female may be guided to the spermatophore or restrained with an embrace called [[amplexus]]. Certain primitive salamanders in the families Sirenidae, [[Hynobiidae]] and [[Cryptobranchidae]] practice external fertilisation in a similar manner to frogs, with the female laying the eggs in water and the male releasing sperm onto the egg mass. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Reproduction"
] | With a few exceptions, frogs use external fertilisation. The male grasps the female tightly with his forelimbs either behind the arms or in front of the back legs, or in the case of ''[[Epipedobates tricolor]]'', around the neck. They remain in amplexus with their cloacae positioned close together while the female lays the eggs and the male covers them with sperm. Roughened nuptial pads on the male's hands aid in retaining grip. Often the male collects and retains the egg mass, forming a sort of basket with the hind feet. An exception is the [[granular poison frog]] (''Oophaga granulifera'') where the male and female place their cloacae in close proximity while facing in opposite directions and then release eggs and sperm simultaneously. The [[tailed frog]] (''Ascaphus truei'') exhibits internal fertilisation. The "tail" is only possessed by the male and is an extension of the cloaca and used to inseminate the female. This frog lives in fast-flowing streams and internal fertilisation prevents the sperm from being washed away before fertilisation occurs. The sperm may be retained in storage tubes attached to the [[oviduct]] until the following spring. Most frogs can be classified as either prolonged or explosive breeders. Typically, prolonged breeders congregate at a breeding site, the males usually arriving first, calling and setting up territories. Other satellite males remain quietly nearby, waiting for their opportunity to take over a territory. The females arrive sporadically, mate selection takes place and eggs are laid. The females depart and territories may change hands. More females appear and in due course, the breeding season comes to an end. Explosive breeders on the other hand are found where temporary pools appear in dry regions after rainfall. These frogs are typically [[wikt:fossorial|fossorial]] species that emerge after heavy rains and congregate at a breeding site. They are attracted there by the calling of the first male to find a suitable place, perhaps a pool that forms in the same place each rainy season. The assembled frogs may call in unison and frenzied activity ensues, the males scrambling to mate with the usually smaller number of females. There is a direct competition between males to win the attention of the females in salamanders and newts, with elaborate courtship displays to keep the female's attention long enough to get her interested in choosing him to [[mating|mate]] with. Some species store [[sperm]] through long breeding seasons, as the extra time may allow for interactions with rival sperm. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Life cycle"
] | Most amphibians go through [[metamorphosis]], a process of significant morphological change after birth. In typical amphibian development, eggs are laid in water and larvae are adapted to an aquatic lifestyle. Frogs, toads and salamanders all hatch from the egg as larvae with external gills. Metamorphosis in amphibians is regulated by [[thyroxine]] concentration in the blood, which stimulates metamorphosis, and [[prolactin]], which counteracts thyroxine's effect. Specific events are dependent on threshold values for different tissues. Because most embryonic development is outside the parental body, it is subject to many adaptations due to specific environmental circumstances. For this reason tadpoles can have horny ridges instead of teeth, whisker-like skin extensions or fins. They also make use of a sensory lateral line organ similar to that of fish. After metamorphosis, these organs become redundant and will be reabsorbed by controlled cell death, called [[apoptosis]]. The variety of adaptations to specific environmental circumstances among amphibians is wide, with many discoveries still being made. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Life cycle",
"Eggs"
] | The egg of an amphibian is typically surrounded by a transparent gelatinous covering secreted by the oviducts and containing [[mucoprotein]] and [[mucopolysaccharide]]. This capsule is permeable to water and gases, and swells considerably as it absorbs water. The ovum is at first rigidly held, but in fertilised eggs the innermost layer liquefies and allows the [[embryo]] to move freely. This also happens in salamander eggs, even when they are unfertilised. Eggs of some salamanders and frogs contain unicellular green algae. These penetrate the jelly envelope after the eggs are laid and may increase the supply of oxygen to the embryo through photosynthesis. They seem to both speed up the development of the larvae and reduce mortality. Most eggs contain the pigment [[melanin]] which raises their temperature through the absorption of light and also protects them against [[ultraviolet radiation]]. Caecilians, some [[plethodontid]] salamanders and certain frogs lay eggs underground that are unpigmented. In the [[wood frog]] (''Rana sylvatica''), the interior of the globular egg cluster has been found to be up to warmer than its surroundings, which is an advantage in its cool northern habitat. The eggs may be deposited singly or in small groups, or may take the form of spherical egg masses, rafts or long strings. In terrestrial caecilians, the eggs are laid in grape-like clusters in burrows near streams. The amphibious salamander ''[[Ensatina]]'' attaches its similar clusters by stalks to underwater stems and roots. The [[Eleutherodactylus planirostris|greenhouse frog]] (''Eleutherodactylus planirostris'') lays eggs in small groups in the soil where they develop in about two weeks directly into juvenile frogs without an intervening larval stage. The [[tungara frog]] (''Physalaemus pustulosus'') builds a floating nest from foam to protect its eggs. First a raft is built, then eggs are laid in the centre, and finally a foam cap is overlaid. The foam has anti-microbial properties. It contains no [[detergent]] but is created by whipping up [[protein]] and [[lectin]] secreted by the female. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Life cycle",
"Larvae"
] | The eggs of amphibians are typically laid in water and hatch into free-living larvae that complete their development in water and later transform into either aquatic or terrestrial adults. In many species of frog and in most lungless salamanders (Plethodontidae), direct development takes place, the larvae growing within the eggs and emerging as miniature adults. Many caecilians and some other amphibians lay their eggs on land, and the newly hatched larvae wriggle or are transported to water bodies. Some caecilians, the [[alpine salamander]] (''Salamandra atra'') and some of the [[Nectophrynoides|African live-bearing toads]] (''Nectophrynoides spp.'') are [[Viviparity|viviparous]]. Their larvae feed on glandular secretions and develop within the female's oviduct, often for long periods. Other amphibians, but not caecilians, are [[Ovoviviparity|ovoviviparous]]. The eggs are retained in or on the parent's body, but the larvae subsist on the yolks of their eggs and receive no nourishment from the adult. The larvae emerge at varying stages of their growth, either before or after metamorphosis, according to their species. The toad genus ''Nectophrynoides'' exhibits all of these developmental patterns among its dozen or so members. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Life cycle",
"Larvae",
"Frogs"
] | Frog larvae are known as tadpoles and typically have oval bodies and long, vertically flattened tails with fins. The free-living larvae are normally fully aquatic, but the tadpoles of some species (such as ''[[Nannophrys ceylonensis]]'') are semi-terrestrial and live among wet rocks. Tadpoles have cartilaginous skeletons, gills for respiration (external gills at first, internal gills later), [[lateral line system]] and large tails that they use for swimming. Newly hatched tadpoles soon develop gill pouches that cover the gills. The lungs develop early and are used as accessory breathing organs, the tadpoles rising to the water surface to gulp air. Some species complete their development inside the egg and hatch directly into small frogs. These larvae do not have gills but instead have specialised areas of skin through which respiration takes place. While tadpoles do not have true teeth, in most species, the jaws have long, parallel rows of small keratinized structures called keradonts surrounded by a horny beak. Front legs are formed under the gill sac and hind legs become visible a few days later. Iodine and T4 (over stimulate the spectacular [[apoptosis]] [programmed cell death] of the cells of the larval gills, tail and fins) also stimulate the [[evolution of nervous systems]] transforming the aquatic, vegetarian tadpole into the terrestrial, carnivorous frog with better neurological, visuospatial, olfactory and cognitive abilities for hunting. In fact, tadpoles developing in ponds and streams are typically [[herbivore|herbivorous]]. Pond tadpoles tend to have deep bodies, large caudal fins and small mouths; they swim in the quiet waters feeding on growing or loose fragments of vegetation. Stream dwellers mostly have larger mouths, shallow bodies and caudal fins; they attach themselves to plants and stones and feed on the surface films of [[algae]] and bacteria. They also feed on [[diatom]], filtered from the water through the [[gill]], and stir up the sediment at bottom of the pond, ingesting edible fragments. They have a relatively long, spiral-shaped gut to enable them to digest this diet. Some species are carnivorous at the tadpole stage, eating insects, smaller tadpoles and fish. Young of the [[Cuban tree frog]] (''Osteopilus septentrionalis'') can occasionally be [[Cannibalism (zoology)|cannibalistic]], the younger tadpoles attacking a larger, more developed tadpole when it is undergoing metamorphosis. At metamorphosis, rapid changes in the body take place as the lifestyle of the frog changes completely. The spiral‐shaped mouth with horny tooth ridges is reabsorbed together with the spiral gut. The animal develops a large jaw, and its gills disappear along with its gill sac. Eyes and legs grow quickly, and a tongue is formed. There are associated changes in the neural networks such as development of stereoscopic vision and loss of the lateral line system. All this can happen in about a day. A few days later, the tail is reabsorbed, due to the higher thyroxine concentration required for this to take place. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Life cycle",
"Larvae",
"Salamanders"
] | At hatching, a typical salamander larva has eyes without lids, teeth in both upper and lower jaws, three pairs of feathery external gills, a somewhat laterally flattened body and a long tail with [[Anatomical terms of location#Dorsal and ventral|dorsal]] and [[Anatomical terms of location#Dorsal and ventral|ventral]] fins. The forelimbs may be partially developed and the hind limbs are rudimentary in pond-living species but may be rather more developed in species that reproduce in moving water. Pond-type larvae often have a pair of balancers, rod-like structures on either side of the head that may prevent the gills from becoming clogged up with sediment. Some members of the genera ''[[Ambystoma]]'' and ''[[Dicamptodon]]'' have larvae that never fully develop into the adult form, but this varies with species and with populations. The [[northwestern salamander]] (''Ambystoma gracile'') is one of these and, depending on environmental factors, either remains permanently in the larval state, a condition known as [[neoteny]], or transforms into an adult. Both of these are able to breed. Neoteny occurs when the animal's growth rate is very low and is usually linked to adverse conditions such as low water temperatures that may change the response of the tissues to the hormone thyroxine. Other factors that may inhibit metamorphosis include lack of food, lack of trace elements and competition from [[conspecific]]. The [[tiger salamander]] (''Ambystoma tigrinum'') also sometimes behaves in this way and may grow particularly large in the process. The adult tiger salamander is terrestrial, but the larva is aquatic and able to breed while still in the larval state. When conditions are particularly inhospitable on land, larval breeding may allow continuation of a population that would otherwise die out. There are fifteen species of [[wikt:obligate|obligate]] neotenic salamanders, including species of ''[[Necturus]]'', ''[[Olm|Proteus]]'' and ''Amphiuma'', and many examples of [[wikt:facultative|facultative]] ones that adopt this strategy under appropriate environmental circumstances. Lungless salamanders in the family Plethodontidae are terrestrial and lay a small number of unpigmented eggs in a cluster among damp leaf litter. Each egg has a large yolk sac and the larva feeds on this while it develops inside the egg, emerging fully formed as a juvenile salamander. The female salamander often broods the eggs. In the genus ''[[Ensatinas]]'', the female has been observed to coil around them and press her throat area against them, effectively massaging them with a mucous secretion. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Life cycle",
"Larvae",
"Salamanders"
] | In newts and salamanders, metamorphosis is less dramatic than in frogs. This is because the larvae are already carnivorous and continue to feed as predators when they are adults so few changes are needed to their digestive systems. Their lungs are functional early, but the larvae do not make as much use of them as do tadpoles. Their gills are never covered by gill sacs and are reabsorbed just before the animals leave the water. Other changes include the reduction in size or loss of tail fins, the closure of gill slits, thickening of the skin, the development of eyelids, and certain changes in dentition and tongue structure. Salamanders are at their most vulnerable at metamorphosis as swimming speeds are reduced and transforming tails are encumbrances on land. Adult salamanders often have an aquatic phase in spring and summer, and a land phase in winter. For adaptation to a water phase, prolactin is the required hormone, and for adaptation to the land phase, thyroxine. External gills do not return in subsequent aquatic phases because these are completely absorbed upon leaving the water for the first time. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Life cycle",
"Larvae",
"Caecilians"
] | Most terrestrial caecilians that lay eggs do so in burrows or moist places on land near bodies of water. The development of the young of ''[[Ichthyophis glutinosus]]'', a species from Sri Lanka, has been much studied. The eel-like larvae hatch out of the eggs and make their way to water. They have three pairs of external red feathery gills, a blunt head with two rudimentary eyes, a lateral line system and a short tail with fins. They swim by undulating their body from side to side. They are mostly active at night, soon lose their gills and make sorties onto land. Metamorphosis is gradual. By the age of about ten months they have developed a pointed head with sensory tentacles near the mouth and lost their eyes, lateral line systems and tails. The skin thickens, embedded scales develop and the body divides into segments. By this time, the caecilian has constructed a burrow and is living on land. In the majority of species of caecilians, the young are produced by viviparity. ''[[Typhlonectes compressicauda]]'', a species from South America, is typical of these. Up to nine larvae can develop in the oviduct at any one time. They are elongated and have paired sac-like gills, small eyes and specialised scraping teeth. At first, they feed on the yolks of the eggs, but as this source of nourishment declines they begin to rasp at the ciliated epithelial cells that line the oviduct. This stimulates the secretion of fluids rich in [[lipid]] and mucoproteins on which they feed along with scrapings from the oviduct wall. They may increase their length sixfold and be two-fifths as long as their mother before being born. By this time they have undergone metamorphosis, lost their eyes and gills, developed a thicker skin and mouth tentacles, and reabsorbed their teeth. A permanent set of teeth grow through soon after birth. The ringed caecilian (''[[Siphonops annulatus]]'') has developed a unique adaptation for the purposes of reproduction. The progeny feed on a skin layer that is specially developed by the adult in a phenomenon known as maternal dermatophagy. The brood feed as a batch for about seven minutes at intervals of approximately three days which gives the skin an opportunity to regenerate. Meanwhile, they have been observed to ingest fluid exuded from the maternal cloaca. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Life cycle",
"Parental care"
] | The care of offspring among amphibians has been little studied but, in general, the larger the number of eggs in a batch, the less likely it is that any degree of parental care takes place. Nevertheless, it is estimated that in up to 20% of amphibian species, one or both adults play some role in the care of the young. Those species that breed in smaller water bodies or other specialised habitats tend to have complex patterns of behaviour in the care of their young. Many woodland salamanders lay clutches of eggs under dead logs or stones on land. The [[black mountain salamander]] (''Desmognathus welteri'') does this, the mother brooding the eggs and guarding them from predation as the embryos feed on the yolks of their eggs. When fully developed, they break their way out of the egg capsules and disperse as juvenile salamanders. The male hellbender, a primitive salamander, excavates an underwater nest and encourages females to lay there. The male then guards the site for the two or three months before the eggs hatch, using body undulations to fan the eggs and increase their supply of oxygen. The male ''[[Colostethus subpunctatus]]'', a tiny frog, protects the egg cluster which is hidden under a stone or log. When the eggs hatch, the male transports the tadpoles on his back, stuck there by a mucous secretion, to a temporary pool where he dips himself into the water and the tadpoles drop off. The male [[Common midwife toad|midwife toad]] (''Alytes obstetricans'') winds egg strings round his thighs and carries the eggs around for up to eight weeks. He keeps them moist and when they are ready to hatch, he visits a pond or ditch and releases the tadpoles. The female [[gastric-brooding frog]] (''Rheobatrachus spp.'') reared larvae in her stomach after swallowing either the eggs or hatchlings; however, this stage was never observed before the species became extinct. The tadpoles secrete a hormone that inhibits digestion in the mother whilst they develop by consuming their very large yolk supply. The [[pouched frog]] (''Assa darlingtoni'') lays eggs on the ground. When they hatch, the male carries the tadpoles around in brood pouches on his hind legs. The aquatic [[Surinam toad]] (''Pipa pipa'') raises its young in pores on its back where they remain until metamorphosis. The granular poison frog (''Oophaga granulifera'') is typical of a number of tree frogs in the poison dart frog family [[Dendrobatidae]]. Its eggs are laid on the forest floor and when they hatch, the tadpoles are carried one by one on the back of an adult to a suitable water-filled crevice such as the [[wikt:axil|axil]] of a leaf or the [[Rosette (botany)|rosette]] of a [[Bromeliaceae|bromeliad]]. The female visits the nursery sites regularly and deposits unfertilised eggs in the water and these are consumed by the tadpoles. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Feeding and diet"
] | With a few exceptions, adult amphibians are [[Predation|predators]], feeding on virtually anything that moves that they can swallow. The diet mostly consists of small prey that do not move too fast such as beetles, caterpillars, earthworms and spiders. The sirens (''[[Siren (genus)|Siren spp.]]'') often ingest aquatic plant material with the invertebrates on which they feed and a Brazilian tree frog (''[[Xenohyla truncata]]'') includes a large quantity of fruit in its diet. The [[Mexican burrowing toad]] (''Rhinophrynus dorsalis'') has a specially adapted tongue for picking up ants and termites. It projects it with the tip foremost whereas other frogs flick out the rear part first, their tongues being hinged at the front. Food is mostly selected by sight, even in conditions of dim light. Movement of the prey triggers a feeding response. Frogs have been caught on fish hooks baited with red flannel and [[Rana clamitans|green frogs]] (''Rana clamitans'') have been found with stomachs full of elm seeds that they had seen floating past. Toads, salamanders and caecilians also use smell to detect prey. This response is mostly secondary because salamanders have been observed to remain stationary near odoriferous prey but only feed if it moves. Cave-dwelling amphibians normally hunt by smell. Some salamanders seem to have learned to recognize immobile prey when it has no smell, even in complete darkness. Amphibians usually swallow food whole but may chew it lightly first to subdue it. They typically have small hinged [[pedicellate teeth]], a feature unique to amphibians. The base and crown of these are composed of [[dentine]] separated by an [[Calcification|uncalcified]] layer and they are replaced at intervals. Salamanders, caecilians and some frogs have one or two rows of teeth in both jaws, but some frogs (''Rana spp.'') lack teeth in the lower jaw, and toads (''Bufo spp.'') have no teeth. In many amphibians there are also [[vomerine teeth]] attached to a facial bone in the roof of the mouth. The [[tiger salamander]] (''Ambystoma tigrinum'') is typical of the frogs and salamanders that hide under cover ready to ambush unwary invertebrates. Others amphibians, such as the ''Bufo spp.'' toads, actively search for prey, while the [[Argentine horned frog]] (''Ceratophrys ornata'') lures inquisitive prey closer by raising its hind feet over its back and vibrating its yellow toes. Among leaf litter frogs in Panama, frogs that actively hunt prey have narrow mouths and are slim, often brightly coloured and toxic, while ambushers have wide mouths and are broad and well-camouflaged. Caecilians do not flick their tongues, but catch their prey by grabbing it with their slightly backward-pointing teeth. The struggles of the prey and further jaw movements work it inwards and the caecilian usually retreats into its burrow. The subdued prey is gulped down whole. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Feeding and diet"
] | When they are newly hatched, frog larvae feed on the yolk of the egg. When this is exhausted some move on to feed on bacteria, algal crusts, detritus and raspings from submerged plants. Water is drawn in through their mouths, which are usually at the bottom of their heads, and passes through branchial food traps between their mouths and their gills where fine particles are trapped in mucus and filtered out. Others have specialised mouthparts consisting of a horny beak edged by several rows of labial teeth. They scrape and bite food of many kinds as well as stirring up the bottom sediment, filtering out larger particles with the papillae around their mouths. Some, such as the spadefoot toads, have strong biting jaws and are carnivorous or even cannibalistic. [[file:Sophisticated-Communication-in-the-Brazilian-Torrent-Frog-Hylodes-japi-pone.0145444.s001.oga|left|thumb|Audio showing Brazilian torrent frog males executing advertisement, peep, and squeal calls.]] | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Vocalization"
] | The calls made by caecilians and salamanders are limited to occasional soft squeaks, grunts or hisses and have not been much studied. A clicking sound sometimes produced by caecilians may be a means of orientation, as in bats, or a form of communication. Most salamanders are considered voiceless, but the [[California giant salamander]] (''Dicamptodon ensatus'') has vocal cords and can produce a rattling or barking sound. Some species of salamander emit a quiet squeak or yelp if attacked. Frogs are much more vocal, especially during the breeding season when they use their voices to attract mates. The presence of a particular species in an area may be more easily discerned by its characteristic call than by a fleeting glimpse of the animal itself. In most species, the sound is produced by expelling air from the lungs over the vocal cords into an [[Gular skin|air sac]] or sacs in the throat or at the corner of the mouth. This may distend like a balloon and acts as a resonator, helping to transfer the sound to the atmosphere, or the water at times when the animal is submerged. The main vocalisation is the male's loud advertisement call which seeks to both encourage a female to approach and discourage other males from intruding on its territory. This call is modified to a quieter courtship call on the approach of a female or to a more aggressive version if a male intruder draws near. Calling carries the risk of attracting predators and involves the expenditure of much energy. Other calls include those given by a female in response to the advertisement call and a release call given by a male or female during unwanted attempts at amplexus. When a frog is attacked, a distress or fright call is emitted, often resembling a scream. The usually nocturnal Cuban tree frog (''Osteopilus septentrionalis'') produces a rain call when there is rainfall during daylight hours. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Territorial behaviour"
] | Little is known of the territorial behaviour of caecilians, but some frogs and salamanders defend home ranges. These are usually feeding, breeding or sheltering sites. Males normally exhibit such behaviour though in some species, females and even juveniles are also involved. Although in many frog species, females are larger than males, this is not the case in most species where males are actively involved in territorial defence. Some of these have specific adaptations such as enlarged teeth for biting or spines on the chest, arms or thumbs. In salamanders, defence of a territory involves adopting an aggressive posture and if necessary attacking the intruder. This may involve snapping, chasing and sometimes biting, occasionally causing the loss of a tail. The behaviour of [[red back salamander]] (''Plethodon cinereus'') has been much studied. 91% of marked individuals that were later recaptured were within a metre (yard) of their original daytime retreat under a log or rock. A similar proportion, when moved experimentally a distance of , found their way back to their home base. The salamanders left odour marks around their territories which averaged in size and were sometimes inhabited by a male and female pair. These deterred the intrusion of others and delineated the boundaries between neighbouring areas. Much of their behaviour seemed stereotyped and did not involve any actual contact between individuals. An aggressive posture involved raising the body off the ground and glaring at the opponent who often turned away submissively. If the intruder persisted, a biting lunge was usually launched at either the tail region or the naso-labial grooves. Damage to either of these areas can reduce the fitness of the rival, either because of the need to regenerate tissue or because it impairs its ability to detect food. In frogs, male territorial behaviour is often observed at breeding locations; calling is both an announcement of ownership of part of this resource and an advertisement call to potential mates. In general, a deeper voice represents a heavier and more powerful individual, and this may be sufficient to prevent intrusion by smaller males. Much energy is used in the vocalization and it takes a toll on the territory holder who may be displaced by a fitter rival if he tires. There is a tendency for males to tolerate the holders of neighbouring territories while vigorously attacking unknown intruders. Holders of territories have a "home advantage" and usually come off better in an encounter between two similar-sized frogs. If threats are insufficient, chest to chest tussles may take place. Fighting methods include pushing and shoving, deflating the opponent's vocal sac, seizing him by the head, jumping on his back, biting, chasing, splashing, and ducking him under the water. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Defence mechanisms"
] | Amphibians have soft bodies with thin skins, and lack claws, defensive armour, or spines. Nevertheless, they have evolved various defence mechanisms to keep themselves alive. The first line of defence in salamanders and frogs is the mucous secretion that they produce. This keeps their skin moist and makes them slippery and difficult to grip. The secretion is often sticky and distasteful or toxic. Snakes have been observed yawning and gaping when trying to swallow [[African clawed frog]] (''Xenopus laevis''), which gives the frogs an opportunity to escape. Caecilians have been little studied in this respect, but the Cayenne caecilian (''Typhlonectes compressicauda'') produces toxic mucus that has killed predatory fish in a feeding experiment in Brazil. In some salamanders, the skin is poisonous. The [[rough-skinned newt]] (''Taricha granulosa'') from North America and other members of its genus contain the neurotoxin [[tetrodotoxin]] (TTX), the most toxic non-protein substance known and almost identical to that produced by [[pufferfish]]. Handling the newts does not cause harm, but ingestion of even the most minute amounts of the skin is deadly. In feeding trials, fish, frogs, reptiles, birds and mammals were all found to be susceptible. The only predators with some tolerance to the poison are certain populations of [[Common Garter Snake|common garter snake]] (''Thamnophis sirtalis''). In locations where both snake and salamander co-exist, the snakes have developed immunity through genetic changes and they feed on the amphibians with impunity. [[Coevolution]] occurs with the newt increasing its toxic capabilities at the same rate as the snake further develops its immunity. Some frogs and toads are toxic, the main poison glands being at the side of the neck and under the warts on the back. These regions are presented to the attacking animal and their secretions may be foul-tasting or cause various physical or neurological symptoms. Altogether, over 200 toxins have been isolated from the limited number of amphibian species that have been investigated. Poisonous species often use bright colouring to warn potential predators of their toxicity. These warning colours tend to be red or yellow combined with black, with the [[fire salamander]] (''Salamandra salamandra'') being an example. Once a predator has sampled one of these, it is likely to remember the colouration next time it encounters a similar animal. In some species, such as the [[fire-bellied toad]] (''Bombina spp.''), the warning colouration is on the belly and these animals adopt a defensive pose when attacked, exhibiting their bright colours to the predator. The frog ''[[Allobates zaparo]]'' is not poisonous, but [[Batesian mimicry|mimics]] the appearance of other toxic species in its locality, a strategy that may deceive predators. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Defence mechanisms"
] | Many amphibians are nocturnal and hide during the day, thereby avoiding diurnal predators that hunt by sight. Other amphibians use [[camouflage]] to avoid being detected. They have various colourings such as mottled browns, greys and olives to blend into the background. Some salamanders adopt defensive poses when faced by a potential predator such as the North American [[northern short-tailed shrew]] (''Blarina brevicauda''). Their bodies writhe and they raise and lash their tails which makes it difficult for the predator to avoid contact with their poison-producing granular glands. A few salamanders will autotomise their tails when attacked, sacrificing this part of their anatomy to enable them to escape. The tail may have a constriction at its base to allow it to be easily detached. The tail is regenerated later, but the energy cost to the animal of replacing it is significant. Some frogs and toads inflate themselves to make themselves look large and fierce, and some spadefoot toads (''[[Pelobates]] spp'') scream and leap towards the attacker. Giant salamanders of the genus ''[[Andrias]]'', as well as [[Ceratophryinae|Ceratophrine]] and ''[[Pyxicephalus]]'' frogs possess sharp teeth and are capable of drawing blood with a defensive bite. The [[blackbelly salamander]] (''Desmognathus quadramaculatus'') can bite an attacking common garter snake (''Thamnophis sirtalis'') two or three times its size on the head and often manages to escape. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Cognition"
] | In amphibians, there is evidence of [[habituation]], [[associative learning]] through both [[Classical conditioning|classical]] and [[instrumental learning]], and discrimination abilities. In one experiment, when offered live fruit flies (''[[Drosophila]] virilis''), salamanders chose the larger of 1 vs 2 and 2 vs 3. Frogs can distinguish between low numbers (1 vs 2, 2 vs 3, but not 3 vs 4) and large numbers (3 vs 6, 4 vs 8, but not 4 vs 6) of prey. This is irrespective of other characteristics, i.e. surface area, volume, weight and movement, although discrimination among large numbers may be based on surface area. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Conservation"
] | Dramatic declines in amphibian populations, including population crashes and mass localized [[extinction]], have been noted since the late 1980s from locations all over the world, and amphibian declines are thus perceived to be one of the most critical threats to global [[biodiversity]]. In 2004, the [[International Union for Conservation of Nature]] (IUCN) reported stating that currently birds, mammals, and amphibians extinction rates were at minimum 48 times greater than natural extinction rates—possibly 1,024 times higher. In 2006 there were believed to be 4,035 species of amphibians that depended on water at some stage during their life cycle. Of these, 1,356 (33.6%) were considered to be threatened and this figure is likely to be an underestimate because it excludes 1,427 species for which there was insufficient data to assess their status. A number of causes are believed to be involved, including [[habitat destruction]] and modification, [[over-exploitation]], [[pollution]], [[introduced species]], [[global warming]], [[endocrine-disrupting chemical|endocrine-disrupting pollutants]], destruction of the [[ozone layer]] ([[ultraviolet radiation]] has shown to be especially damaging to the skin, eyes, and eggs of amphibians), and diseases like [[chytridiomycosis]]. However, many of the causes of amphibian declines are still poorly understood, and are a topic of ongoing discussion. With their complex reproductive needs and permeable skins, amphibians are often considered to be [[ecological indicator]]. In many terrestrial ecosystems, they constitute one of the largest parts of the vertebrate biomass. Any decline in amphibian numbers will affect the patterns of predation. The loss of carnivorous species near the top of the food chain will upset the delicate ecosystem balance and may cause dramatic increases in opportunistic species. In the Middle East, a growing appetite for eating frog legs and the consequent gathering of them for food was linked to an increase in [[mosquito]]. Predators that feed on amphibians are affected by their decline. The [[western terrestrial garter snake]] (''Thamnophis elegans'') in California is largely aquatic and depends heavily on two species of frog that are decreasing in numbers, the [[Yosemite toad]] (''Bufo canorus'') and the [[mountain yellow-legged frog]] (''Rana muscosa''), putting the snake's future at risk. If the snake were to become scarce, this would affect birds of prey and other predators that feed on it. Meanwhile, in the ponds and lakes, fewer frogs means fewer tadpoles. These normally play an important role in controlling the growth of algae and also forage on [[detritus]] that accumulates as sediment on the bottom. A reduction in the number of tadpoles may lead to an overgrowth of algae, resulting in depletion of oxygen in the water when the algae later die and decompose. Aquatic invertebrates and fish might then die and there would be unpredictable ecological consequences. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[
"Conservation"
] | A [[global strategy]] to stem the crisis was released in 2005 in the form of the Amphibian Conservation Action Plan. Developed by over eighty leading experts in the field, this call to action details what would be required to curtail amphibian declines and extinctions over the following five years and how much this would cost. The Amphibian Specialist Group of the IUCN is spearheading efforts to implement a comprehensive global strategy for amphibian conservation. [[Amphibian Ark]] is an organization that was formed to implement the ex-situ conservation recommendations of this plan, and they have been working with zoos and aquaria around the world, encouraging them to create assurance colonies of threatened amphibians. One such project is the Panama Amphibian Rescue and Conservation Project that built on existing conservation efforts in Panama to create a country-wide response to the threat of chytridiomycosis. | 621 | Amphibian | [
"Amphibians",
"Amphibious organisms",
"Animal classes",
"Extant Late Devonian first appearances",
"Taxa named by John Edward Gray"
] | [
"List of amphibian genera",
"List of threatened reptiles and amphibians of the United States",
"List of amphibians"
] |
[] | '''Alaska''' (; ; ; ; [[Central Alaskan Yup'ik language|Yup'ik]]: ''Alaskaq''; ) is a [[U.S. state]] in the [[Western United States]], on the [[northwest]] extremity of the country's [[West Coast of the United States|west coast]]. A [[enclave and exclave|semi-exclave]] of the U.S., it borders the [[Provinces and territories of Canada|Canadian province]] of [[British Columbia]] and territory of [[Yukon]] to the east and has a [[maritime border]] with Russia's [[Chukotka Autonomous Okrug]] to the west, just across the [[Bering Strait]]. To the north are the [[Chukchi Sea|Chukchi]] and [[Beaufort Sea|Beaufort]] seas of the Arctic Ocean, while the [[Pacific Ocean]] lies to the south and southwest. Alaska is by far the [[list of U.S. states and territories by area|largest U.S. state]] by area, comprising more total area than the next three largest states [[Texas]], [[California]], and [[Montana]] combined, and the [[list of country subdivisions by area|seventh largest subnational division in the world]]. It is the [[list of U.S. states and territories by population|third-least populous]] and the [[list of U.S. states and territories by population density|most sparsely populated]] state, but by far the continent's most populous territory located mostly north of the [[60th parallel north|60th parallel]], with a population of 736,081 as of 2020 — more than quadruple the combined populations of [[Northern Canada]] and [[Greenland]]. Approximately half of Alaska's residents live within the [[Anchorage metropolitan area]]. The state capital of [[Juneau, Alaska|Juneau]] is the second-[[list of United States cities by area|largest city in the United States by area]], comprising more territory than the states of [[Rhode Island]] and [[Delaware]]. The former capital of Alaska, [[Sitka, Alaska|Sitka]], is the largest US city by area. Alaska was occupied by various indigenous peoples for thousands of years before the arrival of Europeans. The state is considered the entry point for the settlement of [[North America]] by way of the [[Bering land bridge]]. The [[Russians]] were the first Europeans to settle the area beginning in the 18th century, eventually establishing [[Russian America]], which spanned most of the current state. The expense and difficulty of maintaining this distant possession prompted [[Alaska Purchase|its sale to the U.S.]] in 1867 for [[US$]].2 million (equivalent to $ million in ), or approximately two cents per acre ($4.74/km). The area went through several administrative changes before becoming organized as a [[territories of the United States|territory]] on May 11, 1912. It was admitted as the 49th state of the U.S. on January 3, 1959. While it has one of the smallest state economies in the country, Alaska's [[list of U.S. states by GDP per capita|per capita income is among the highest]], owing to a diversified economy dominated by fishing, natural gas, and [[petroleum|oil]], all of which it has in abundance. [[United States armed forces]] bases and [[tourism in Alaska|tourism]] are also a significant part of the [[economy of Alaska|economy]]; more than half the state is federally owned public land, including a multitude of [[United States National Forest|national forests]], parks, and [[national wildlife refuge|wildlife refuges]]. | 624 | Alaska | [
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"Former Russian colonies",
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"States of the United States",
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"Index of Alaska-related articles",
"Outline of Alaska"
] |
[] | The [[Alaska Natives|indigenous population]] of Alaska is proportionally the highest of any U.S. state, at over 15 percent. Close to two dozen native languages are spoken, and Alaskan Natives exercise considerable influence in local and state politics. | 624 | Alaska | [
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"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Etymology"
] | The name "Alaska" () was introduced in the [[Russian America|Russian colonial period]] when it was used to refer to the [[Alaska Peninsula]]. It was derived from an [[Aleut language|Aleut-language]] [[idiom]], which figuratively refers to the mainland. Literally, it means ''object to which the action of the sea is directed''. | 624 | Alaska | [
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"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography"
] | Located at the northwest corner of [[North America]], Alaska is the northernmost and westernmost state in the United States, but also has the most easterly longitude in the United States because the [[Aleutian Islands]] extend into the [[Eastern Hemisphere]]. Alaska is the only non-[[Contiguous United States|contiguous]] U.S. state on continental North America; about of [[British Columbia]] (Canada) separates Alaska from [[Washington (state)|Washington]]. It is technically part of the [[Continental United States|continental U.S.]], but is sometimes not included in colloquial use; Alaska is not part of the [[Contiguous United States|contiguous U.S.]], often called [[Outside (Alaska)|"the Lower 48"]]. The capital city, [[Juneau]], is situated on the mainland of the North American continent but is not connected by road to the rest of the North American highway system. The state is bordered by Canada's [[Yukon]] and [[British Columbia]] to the east (making it the only state to border a [[Provinces and territories of Canada|Canadian territory]]), the [[Gulf of Alaska]] and the Pacific Ocean to the south and southwest, the [[Bering Sea]], [[Bering Strait]], and [[Chukchi Sea]] to the west and the Arctic Ocean to the north. Alaska's territorial waters touch Russia's territorial waters in the Bering Strait, as the Russian [[Big Diomede Island]] and Alaskan [[Little Diomede Island]] are only apart. Alaska has a longer coastline than all the other U.S. states combined. At in area, Alaska is by far the largest state in the United States, and is more than twice the size of the second-largest U.S. state, [[Texas]]. Alaska is the seventh [[List of the largest country subdivisions by area|largest subnational division in the world]], and if it was an independent nation would be the 16th largest country in the world, as it is larger than [[Iran]]. | 624 | Alaska | [
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"States and territories established in 1959",
"States of the United States",
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"U.S. states with multiple time zones",
"1959 establishments in the United States",
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"Index of Alaska-related articles",
"Outline of Alaska"
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[
"Geography",
"Regions"
] | There are no officially defined borders demarcating the various regions of Alaska, but there are six widely accepted regions: | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
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"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Regions",
"South Central"
] | The most populous region of Alaska, containing [[Anchorage]], the [[Matanuska-Susitna Valley]] and the [[Kenai Peninsula]]. Rural, mostly unpopulated areas south of the [[Alaska Range]] and west of the [[Wrangell Mountains]] also fall within the definition of South Central, as do the [[Prince William Sound]] area and the communities of [[Cordova, Alaska|Cordova]] and [[Valdez, Alaska|Valdez]]. | 624 | Alaska | [
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"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Regions",
"Southeast"
] | Also referred to as the Panhandle or [[Inside Passage]], this is the region of Alaska closest to the contiguous states. As such, this was where most of the initial non-indigenous settlement occurred in the years following the [[Alaska Purchase]]. The region is dominated by the [[Alexander Archipelago]] as well as the [[Tongass National Forest]], the largest national forest in the United States. It contains the state capital [[Juneau]], the former capital [[Sitka, Alaska|Sitka]], and [[Ketchikan]], at one time Alaska's largest city. The [[Alaska Marine Highway]] provides a vital surface transportation link throughout the area and country, as only three communities ([[Haines, Alaska|Haines]], [[Hyder, Alaska|Hyder]] and [[Skagway, Alaska|Skagway]]) enjoy direct connections to the contiguous North American road system. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Regions",
"Interior"
] | The Interior is the largest region of Alaska; much of it is uninhabited wilderness. [[Fairbanks, Alaska|Fairbanks]] is the only large city in the region. [[Denali National Park and Preserve]] is located here. [[Denali]], formerly Mount McKinley, is the highest mountain in North America, and is also located here. | 624 | Alaska | [
"Alaska",
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"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Regions",
"Southwest"
] | Southwest Alaska is a sparsely inhabited region stretching some inland from the Bering Sea. Most of the population lives along the coast. [[Kodiak Island]] is also located in Southwest. The massive [[Yukon–Kuskokwim Delta]], one of the largest river deltas in the world, is here. Portions of the [[Alaska Peninsula]] are considered part of Southwest, with the remaining portions included with the Aleutian Islands (see below). | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Regions",
"North Slope"
] | The North Slope is mostly [[tundra]] peppered with small villages. The area is known for its massive reserves of crude oil and contains both the [[National Petroleum Reserve–Alaska]] and the [[Prudhoe Bay Oil Field]]. The city of [[Utqiaġvik, Alaska|Utqiaġvik]], formerly known as Barrow, is the northernmost city in the United States and is located here. The [[Northwest Arctic Borough, Alaska|Northwest Arctic area]], anchored by [[Kotzebue, Alaska|Kotzebue]] and also containing the [[Kobuk River]] valley, is often regarded as being part of this region. However, the respective [[Inupiat people|Inupiat]] of the North Slope and of the Northwest Arctic seldom consider themselves to be one people. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Regions",
"Aleutian Islands"
] | More than 300 small volcanic islands make up this chain, which stretches more than into the Pacific Ocean. Some of these islands fall in the Eastern Hemisphere, but the [[International Date Line]] was drawn west of [[180th meridian|180°]] to keep the whole state, and thus the entire North American continent, within the same legal day. Two of the islands, [[Attu Island|Attu]] and [[Kiska]], were occupied by Japanese forces during World War II. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Natural features"
] | With its myriad islands, Alaska has nearly of tidal shoreline. The [[Aleutian Islands]] chain extends west from the southern tip of the [[Alaska Peninsula]]. Many active [[volcano]] are found in the Aleutians and in coastal regions. [[Unimak Island]], for example, is home to [[Mount Shishaldin]], which is an occasionally smoldering volcano that rises to above the North Pacific. The chain of volcanoes extends to [[Mount Spurr]], west of Anchorage on the mainland. Geologists have identified Alaska as part of [[Wrangellia]], a large region consisting of multiple states and Canadian provinces in the [[Pacific Northwest]], which is actively undergoing [[plate tectonics|continent building]]. One of the world's largest tides occurs in [[Turnagain Arm]], just south of Anchorage, where tidal differences can be more than . | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Lakes"
] | Alaska has more than three million lakes. [[Marshland]] and wetland [[permafrost]] cover (mostly in northern, western and southwest flatlands). Glacier ice covers about of Alaska. The [[Bering Glacier]] is the largest glacier in North America, covering alone. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Land ownership"
] | According to an October 1998 report by the [[United States Bureau of Land Management]], approximately 65% of Alaska is owned and managed by the [[Federal government of the United States|U.S. federal government]] as public lands, including a multitude of [[United States National Forest|national forests]], national parks, and [[national wildlife refuge]]. Of these, the [[Bureau of Land Management]] manages , or 23.8% of the state. The [[Arctic National Wildlife Refuge]] is managed by the [[United States Fish and Wildlife Service]]. It is the world's largest wildlife refuge, comprising . Of the remaining land area, the state of Alaska owns , its entitlement under the [[Alaska Statehood Act]]. A portion of that acreage is occasionally ceded to the organized boroughs presented above, under the statutory provisions pertaining to newly formed boroughs. Smaller portions are set aside for rural subdivisions and other homesteading-related opportunities. These are not very popular due to the often remote and roadless locations. The [[University of Alaska]], as a [[land grant university]], also owns substantial acreage which it manages independently. Another are owned by 12 regional, and scores of local, Native corporations created under the [[Alaska Native Claims Settlement Act]] (ANCSA) of 1971. [[Alaska Native Regional Corporation|Regional Native corporation]] [[Doyon, Limited]] often promotes itself as the largest private landowner in Alaska in advertisements and other communications. Provisions of ANCSA allowing the corporations' land holdings to be sold on the open market starting in 1991 were repealed before they could take effect. Effectively, the corporations hold title (including subsurface title in many cases, a privilege denied to individual Alaskans) but cannot sell the land. [[Alaska Native Allotment Act|Individual Native allotments]] can be and are sold on the open market, however. Various private interests own the remaining land, totaling about one percent of the state. Alaska is, by a large margin, the state with the smallest percentage of private land ownership when Native corporation holdings are excluded. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
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"1959 establishments in the United States",
"Western United States"
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"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Geography",
"Climate"
] | The climate in South and Southeast Alaska is a mid-latitude [[oceanic climate]] ([[Köppen climate classification]]: ''Cfb''), and a subarctic oceanic climate (Köppen ''Cfc'') in the northern parts. On an annual basis, Southeast is both the wettest and warmest part of Alaska with milder temperatures in the winter and high precipitation throughout the year. Juneau averages over of precipitation a year, and [[Ketchikan, Alaska|Ketchikan]] averages over . This is also the only region in Alaska in which the average daytime high temperature is above freezing during the winter months. The climate of [[Anchorage, Alaska|Anchorage]] and south central Alaska is mild by Alaskan standards due to the region's proximity to the seacoast. While the area gets less rain than southeast Alaska, it gets more snow, and days tend to be clearer. On average, [[Anchorage, Alaska|Anchorage]] receives of precipitation a year, with around of snow, although there are areas in the south central which receive far more snow. It is a subarctic climate ([[Köppen climate classification#GROUP D: Continental/microthermal climate|Köppen: ''Dfc'']]) due to its brief, cool summers. The climate of [[Southwest Alaska|Western Alaska]] is determined in large part by the [[Bering Sea]] and the [[Gulf of Alaska]]. It is a subarctic oceanic climate in the southwest and a continental subarctic climate farther north. The temperature is somewhat moderate considering how far north the area is. This region has a tremendous amount of variety in precipitation. An area stretching from the northern side of the Seward Peninsula to the [[Kobuk River]] valley (i. e., the region around [[Kotzebue Sound]]) is technically a [[desert]], with portions receiving less than of precipitation annually. On the other extreme, some locations between [[Dillingham, Alaska|Dillingham]] and [[Bethel, Alaska|Bethel]] average around of precipitation. The climate of the interior of Alaska is subarctic. Some of the highest and lowest temperatures in Alaska occur around the area near [[Fairbanks, Alaska|Fairbanks]]. The summers may have temperatures reaching into the 90s °F (the low-to-mid 30s °C), while in the winter, the temperature can fall below . Precipitation is sparse in the Interior, often less than a year, but what precipitation falls in the winter tends to stay the entire winter. The highest and lowest recorded temperatures in Alaska are both in the Interior. The highest is in [[Fort Yukon, Alaska|Fort Yukon]] (which is just inside the arctic circle) on June 27, 1915, making Alaska tied with Hawaii as the state with the lowest high temperature in the United States. The lowest official Alaska temperature is in [[Prospect Creek, Alaska|Prospect Creek]] on January 23, 1971, one degree above the lowest temperature recorded in continental North America (in [[Snag, Yukon|Snag, Yukon, Canada]]). The climate in the extreme north of Alaska is [[polar climate|Arctic]] ([[Köppen climate classification#GROUP E: Polar climates|Köppen: ''ET'']]) with long, very cold winters and short, cool summers. Even in July, the average low temperature in [[Utqiaġvik, Alaska|Utqiaġvik]] is . Precipitation is light in this part of Alaska, with many places averaging less than per year, mostly as snow which stays on the ground almost the entire year. | 624 | Alaska | [
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"States and territories established in 1959",
"States of the United States",
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"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
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"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"History",
"Pre-colonization"
] | Numerous indigenous peoples occupied Alaska for thousands of years before the arrival of European peoples to the area. Linguistic and DNA studies done here have provided evidence for the settlement of North America by way of the [[Bering land bridge]]. At the [[Upward Sun River site]] in the Tanana River Valley in Alaska, remains of a six-week-old infant were found. The baby's DNA showed that she belonged to a population that was genetically separate from other native groups present elsewhere in the [[New World]] at the end of the [[Pleistocene]]. Ben Potter, the [[University of Alaska Fairbanks]] archaeologist who unearthed the remains at the Upward Sun River site in 2013, named this new group [[Ancient Beringians]]. The [[Tlingit people]] developed a society with a [[matrilineal]] kinship system of property inheritance and descent in what is today Southeast Alaska, along with parts of British Columbia and the Yukon. Also in Southeast were the [[Haida people|Haida]], now well known for their unique arts. The [[Tsimshian]] people came to Alaska from British Columbia in 1887, when President [[Grover Cleveland]], and later the U.S. Congress, granted them permission to settle on [[Annette Island]] and found the town of [[Metlakatla, Alaska|Metlakatla]]. All three of these peoples, as well as other [[indigenous peoples of the Pacific Northwest Coast]], experienced [[smallpox]] outbreaks from the late 18th through the mid-19th century, with the most devastating [[epidemics]] occurring in the 1830s and 1860s, resulting in high fatalities and social disruption. The Aleutian Islands are still home to the [[Aleut people]]'s seafaring society, although they were the first Native Alaskans to be exploited by the Russians. Western and Southwestern Alaska are home to the [[Yup'ik]], while their cousins the [[Alutiiq people|Alutiiq ~ Sugpiaq]] live in what is now Southcentral Alaska. The [[Gwich'in people]] of the northern Interior region are [[Alaskan Athabaskans|Athabaskan]] and primarily known today for their dependence on the caribou within the much-contested [[Arctic National Wildlife Refuge]]. The North Slope and [[Little Diomede Island]] are occupied by the widespread [[Inupiat people]]. | 624 | Alaska | [
"Alaska",
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"States and territories established in 1959",
"States of the United States",
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"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
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"Index of Alaska-related articles",
"Outline of Alaska"
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[
"History",
"Colonization"
] | Some researchers believe the first Russian settlement in Alaska was established in the 17th century. According to this hypothesis, in 1648 several [[Koch (boat)|koches]] of [[Semyon Dezhnyov]]'s expedition came ashore in Alaska by storm and founded this settlement. This hypothesis is based on the testimony of [[Chukchi people|Chukchi]] geographer Nikolai Daurkin, who had visited Alaska in 1764–1765 and who had reported on a village on the Kheuveren River, populated by "bearded men" who "pray to the [[icons]]". Some modern researchers associate Kheuveren with [[Koyuk River]]. The first European vessel to reach Alaska is generally held to be the ''St. Gabriel'' under the authority of the surveyor [[Mikhail Gvozdev|M. S. Gvozdev]] and assistant navigator [[Ivan Fyodorov (navigator)|I. Fyodorov]] on August 21, 1732, during an expedition of Siberian cossack A. F. Shestakov and Russian explorer [[Dmitry Pavlutsky]] (1729–1735). Another European contact with Alaska occurred in 1741, when [[Vitus Bering]] led an [[second Kamchatka expedition|expedition]] for the Russian Navy aboard the ''St. Peter''. After his crew returned to Russia with [[sea otter]] pelts judged to be the finest fur in the world, small associations of fur traders began to sail from the shores of Siberia toward the Aleutian Islands. The first permanent European settlement was founded in 1784. Between 1774 and 1800, [[Viceroyalty of New Spain|Spain]] sent several [[Spanish expeditions to the Pacific Northwest|expeditions to Alaska]] to assert its claim over the Pacific Northwest. In 1789, a Spanish settlement and [[Fort San Miguel|fort]] were built in [[Nootka Sound]]. These expeditions gave names to places such as [[Valdez, Alaska|Valdez]], [[Bucareli Sound]], and [[Cordova, Alaska|Cordova]]. Later, the [[Russian-American Company]] carried out an expanded colonization program during the early-to-mid-19th century. [[Sitka, Alaska|Sitka]], renamed [[New Archangel]] from 1804 to 1867, on [[Baranof Island]] in the [[Alexander Archipelago]] in what is now [[Southeast Alaska]], became the capital of [[Russian America]]. It remained the capital after the colony was transferred to the United States. The Russians never fully colonized Alaska, and the colony was never very profitable. Evidence of Russian settlement in names and churches survive throughout southeast Alaska. | 624 | Alaska | [
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[
"History",
"Colonization"
] | [[William H. Seward]], the 24th [[United States Secretary of State]], negotiated the [[Alaska Purchase]] (also known as Seward's Folly) with the Russians in 1867 for $7.2 million. Russia's contemporary ruler [[Tsar]] [[Alexander II of Russia|Alexander II]], the [[Emperor of the Russian Empire]], [[King of Poland]] and [[Grand Duke of Finland]], also planned the sale; the purchase was made on March 30, 1867. Six months later the commissioners arrived in Sitka and the formal transfer was arranged; the formal flag-raising took place at Fort Sitka on October 18, 1867. In the ceremony 250 uniformed U.S. soldiers marched to the governor's house at "Castle Hill", where the Russian troops lowered the Russian flag and the U.S. flag was raised. This event is celebrated as [[Alaska Day]], a legal holiday on October 18. Alaska was loosely governed by the military initially, and was administered as a [[District of Alaska|district]] starting in 1884, with a governor appointed by the President of the United States. A federal [[United States territorial court|district court]] was headquartered in Sitka. For most of Alaska's first decade under the United States flag, Sitka was the only community inhabited by American settlers. They organized a "provisional city government", which was Alaska's first municipal government, but not in a legal sense. Legislation allowing Alaskan communities to legally incorporate as cities did not come about until 1900, and [[Home rule#Home rule in the United States|home rule]] for cities was extremely limited or unavailable until statehood took effect in 1959. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"History",
"Alaska as an incorporated U.S. territory"
] | Starting in the 1890s and stretching in some places to the early 1910s, gold rushes in Alaska and the nearby [[Yukon|Yukon Territory]] brought thousands of miners and settlers to Alaska. Alaska was officially incorporated as an organized territory in 1912. Alaska's capital, which had been in [[Sitka, Alaska|Sitka]] until 1906, was moved north to [[Juneau, Alaska|Juneau]]. Construction of the [[Alaska Governor's Mansion]] began that same year. European immigrants from Norway and Sweden also settled in southeast Alaska, where they entered the fishing and logging industries. During World War II, the [[Aleutian Islands Campaign]] focused on [[Attu Island|Attu]], [[Agattu]] and [[Kiska Island|Kiska]], all which were occupied by the [[Empire of Japan]]. During the Japanese occupation, a white American civilian and two [[United States Navy]] personnel were killed at Attu and Kiska respectively, and nearly a total of 50 Aleut civilians and eight sailors were interned in Japan. About half of the Aleuts died during the period of internment. [[Unalaska]]/[[Dutch Harbor]] and [[Adak, Alaska|Adak]] became significant bases for the [[United States Army]], [[United States Army Air Forces]] and [[United States Navy]]. The United States [[Lend-Lease]] program involved flying American warplanes through Canada to Fairbanks and then Nome; Soviet pilots took possession of these aircraft, ferrying them to fight the German invasion of the Soviet Union. The construction of military bases contributed to the population growth of some Alaskan cities. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"History",
"Statehood"
] | Statehood for Alaska was an important cause of [[James Wickersham]] early in his tenure as a congressional delegate. Decades later, the statehood movement gained its first real momentum following a territorial referendum in 1946. The Alaska Statehood Committee and Alaska's Constitutional Convention would soon follow. Statehood supporters also found themselves fighting major battles against political foes, mostly in the U.S. Congress but also within Alaska. Statehood was approved by Congress on July 7, 1958. Alaska was officially proclaimed a state on January 3, 1959. In 1960, the Census Bureau reported Alaska's population as 77.2% White, 3% Black, and 18.8% American Indian and Alaska Native. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"History",
"Good Friday earthquake"
] | On March 27, 1964, the massive [[1964 Alaska earthquake|Good Friday earthquake]] killed 133 people and destroyed several villages and portions of large coastal communities, mainly by the resultant [[tsunamis]] and landslides. It was the [[Largest earthquakes by magnitude|second-most-powerful earthquake]] in recorded history, with a [[moment magnitude scale|moment magnitude]] of 9.2 (more than a thousand times as powerful as the [[1989 Loma Prieta earthquake|1989 San Francisco earthquake]]). The time of day (5:36 pm), time of year (spring) and location of the [[epicenter]] were all cited as factors in potentially sparing thousands of lives, particularly in Anchorage. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"History",
"Oil"
] | The 1968 discovery of oil at [[Prudhoe Bay]] and the 1977 completion of the [[Trans-Alaska Pipeline System]] led to an oil boom. Royalty revenues from oil have funded large state budgets from 1980 onward. That same year, not coincidentally, Alaska repealed its state income tax. In 1989, the ''[[Exxon Valdez]]'' hit a reef in the [[Prince William Sound]], [[Exxon Valdez oil spill|spilling]] more than of crude oil over of coastline. Today, the battle between philosophies of development and conservation is seen in the contentious debate over oil drilling in the [[Arctic National Wildlife Refuge]] and the proposed [[Pebble Mine]]. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"History",
"Alaska Heritage Resources Survey"
] | The Alaska Heritage Resources Survey (AHRS) is a restricted [[inventory]] of all reported [[historic site|historic]] and [[prehistoric]] sites within the state of Alaska; it is maintained by the Office of History and Archaeology. The survey's inventory of cultural resources includes objects, structures, buildings, sites, districts, and travel ways, with a general provision that they are more than fifty years old. , more than 35,000 sites have been reported. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Demographics"
] | The [[United States Census Bureau]] found in the [[2020 United States census]] that the population of Alaska was 736,081 on April 1, 2020, a 3.6% increase since the [[2010 United States Census]]. In 2010, Alaska ranked as the 47th state by population, ahead of [[North Dakota]], [[Vermont]], and [[Wyoming]] (and Washington, D.C.). Estimates show North Dakota ahead . Alaska is the least densely populated state, and one of the most sparsely populated areas in the world, at , with the next state, Wyoming, at . Alaska is by far the largest U.S. state by [[List of U.S. states and territories by area|area]], and the tenth wealthiest (per capita income). , the state's unemployment rate was 6.6%. , it is one of 14 U.S. states that still have only one telephone [[Telephone numbering plan|area code]]. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Demographics",
"Race and ethnicity"
] | According to the [[2010 United States Census]], Alaska had a population of 710,231. In terms of race and ethnicity, the state was 66.7% [[White American|White]] (64.1% Non-Hispanic [[Non-Hispanic Whites|White]]), 14.8% [[Native Americans in the United States|American Indian]] and Alaska Native, 5.4% [[Asian American|Asian]], 3.3% [[African American|Black]] or African American, 1.0% Native Hawaiian and Other Pacific Islander, 1.6% from Some Other Race, and 7.3% from Two or More Races. [[Hispanic and Latino Americans|Hispanics]] or Latinos of any race made up 5.5% of the population. , 50.7% of Alaska's population younger than one year of age belonged to minority groups (i.e., did not have two parents of non-Hispanic white ancestry). | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Demographics",
"Languages"
] | According to the 2011 [[American Community Survey]], 83.4% of people over the age of five spoke only English at home. About 3.5% spoke Spanish at home, 2.2% spoke another [[Indo-European languages|Indo-European language]], about 4.3% spoke an [[Languages of Asia|Asian]] language (including [[Tagalog language|Tagalog]]), and about 5.3% spoke other languages at home. The [[Alaska Native Language Center]] at the [[University of Alaska Fairbanks]] claims that at least 20 [[Alaska Native languages|Alaskan native languages]] exist and there are also some languages with different dialects. Most of Alaska's native languages belong to either the [[Eskimo–Aleut languages|Eskimo–Aleut]] or [[Na-Dene languages|Na-Dene]] language families; however, some languages are thought to be [[Language isolate|isolates]] (e.g. [[Haida language|Haida]]) or have not yet been classified (e.g. [[Tsimshianic languages|Tsimshianic]]). nearly all of Alaska's native languages were classified as either threatened, shifting, moribund, nearly extinct, or dormant languages. A total of 5.2% of Alaskans speak one of the state's 20 [[Indigenous languages of the Americas|indigenous languages]], known locally as "native languages". In October 2014, the governor of Alaska signed a bill declaring the state's 20 indigenous languages to have official status. This bill gave them symbolic recognition as official languages, though they have not been adopted for official use within the government. The 20 languages that were included in the bill are: (1) [[Inupiat language|Inupiaq]] (2) [[Central Siberian Yupik language|Siberian Yupik]] (3) [[Central Alaskan Yup'ik language|Central Alaskan Yup'ik]] (4) [[Alutiiq language|Alutiiq]] (5) [[Aleut language|Unangax]] (6) [[Dena'ina language|Dena'ina]] (7) [[Deg Xinag language|Deg Xinag]] (8) [[Holikachuk language|Holikachuk]] (9) [[Koyukon language|Koyukon]] (10) [[Upper Kuskokwim language|Upper Kuskokwim]] (11) [[Gwich'in language|Gwich'in]] (12) [[Lower Tanana language|Tanana]] (13) [[Upper Tanana language|Upper Tanana]] (14) [[Tanacross language|Tanacross]] (15) [[Hän language|Hän]] (16) [[Ahtna language|Ahtna]] (17) [[Eyak language|Eyak]] (18) [[Tlingit language|Tlingit]] (19) [[Haida language|Haida]] (20) [[Coast Tsimshian dialect|Tsimshian]] | 624 | Alaska | [
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"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Demographics",
"Religion"
] | According to statistics collected by the Association of Religion Data Archives from 2010, about 34% of Alaska residents were members of religious congregations. 100,960 people identified as [[Evangelical Protestant]], 50,866 as Roman Catholic, and 32,550 as mainline Protestants. Roughly 4% are Mormon, 0.5% are Jewish, 1% are Muslim, 0.5% are Buddhist, 0.2% are Baháʼí, and 0.5% are Hindu. The largest religious denominations in Alaska were the [[Catholic Church]] with 50,866 adherents, non-denominational Evangelical Protestants with 38,070 adherents, [[The Church of Jesus Christ of Latter-day Saints]] with 32,170 adherents, and the [[Southern Baptist Convention]] with 19,891 adherents. Alaska has been identified, along with Pacific Northwest states Washington and Oregon, as being [[Unchurched Belt|the least religious states of the USA]], in terms of church membership, In 1795, the First [[Russian Orthodox Church]] was established in [[Kodiak Island Borough, Alaska|Kodiak]]. Intermarriage with Alaskan Natives helped the Russian immigrants integrate into society. As a result, an increasing number of Russian Orthodox churches gradually became established within Alaska. Alaska also has the largest [[Quaker]] population (by percentage) of any state. In 2009 there were 6,000 Jews in Alaska (for whom observance of [[halakha]] [[Jewish law in the polar regions|may pose special problems]]). Alaskan Hindus often share venues and celebrations with members of other Asian religious communities, including [[Sikhism|Sikhs]] and [[Jainism|Jains]]. In 2010, Alaskan Hindus established the [[Sri Ganesha Temple of Alaska]], making it the first Hindu Temple in Alaska and the northernmost Hindu Temple in the world. There are an estimated 2,000–3,000 Hindus in Alaska. The vast majority of Hindus live in Anchorage or Fairbanks. Estimates for the number of Muslims in Alaska range from 2,000 to 5,000. The [[Islamic Community Center of Anchorage, Alaska|Islamic Community Center of Anchorage]] began efforts in the late 1990s to construct a mosque in Anchorage. They broke ground on a building in south Anchorage in 2010 and were nearing completion in late 2014. When completed, the mosque will be the first in the state and one of the northernmost mosques in the world. There's also a [[Baháʼí Faith|Baháʼí]] Center. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Economy"
] | (-) Total employment (2016): 266,072 (-) Number of employer establishments: 21,077 The 2018 [[gross state product]] was $55 billion, 48th in the nation. Its [[List of U.S. states by GDP per capita (nominal)|per capita personal income]] for 2018 was $73,000, ranking 7th in the nation. According to a 2013 study by Phoenix Marketing International, Alaska had the fifth-largest number of millionaires per capita in the United States, with a ratio of 6.75 percent. The oil and gas industry dominates the Alaskan economy, with more than 80% of the state's revenues derived from petroleum extraction. Alaska's main export product (excluding oil and natural gas) is seafood, primarily salmon, cod, Pollock and crab. Agriculture represents a very small fraction of the Alaskan economy. Agricultural production is primarily for consumption within the state and includes nursery stock, dairy products, vegetables, and livestock. Manufacturing is limited, with most foodstuffs and general goods imported from elsewhere. Employment is primarily in government and industries such as natural resource extraction, shipping, and transportation. Military bases are a significant component of the economy in the Fairbanks North Star, Anchorage and Kodiak Island boroughs, as well as Kodiak. Federal subsidies are also an important part of the economy, allowing the state to keep taxes low. Its industrial outputs are crude petroleum, natural gas, coal, gold, precious metals, zinc and other mining, seafood processing, timber and wood products. There is also a growing service and tourism sector. Tourists have contributed to the economy by supporting local lodging. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Economy",
"Energy"
] | Alaska has vast energy resources, although its oil reserves have been largely depleted. Major oil and gas reserves were found in the [[Alaska North Slope]] (ANS) and Cook Inlet basins, but according to the [[Energy Information Administration]], by February 2014 Alaska had fallen to fourth place in the nation in crude oil production after Texas, North Dakota, and California. Prudhoe Bay on Alaska's North Slope is still the second highest-yielding oil field in the United States, typically producing about , although by early 2014 North Dakota's [[Bakken Formation]] was producing over . Prudhoe Bay was the largest [[conventional oil]] field ever discovered in North America, but was much smaller than Canada's enormous [[Athabasca oil sands]] field, which by 2014 was producing about of [[unconventional oil]], and had hundreds of years of producible reserves at that rate. The [[Trans-Alaska Pipeline]] can transport and pump up to of crude oil per day, more than any other crude oil pipeline in the United States. Additionally, substantial coal deposits are found in Alaska's bituminous, sub-bituminous, and lignite coal basins. The [[United States Geological Survey]] estimates that there are of undiscovered, technically recoverable gas from natural gas hydrates on the Alaskan North Slope. Alaska also offers some of the highest hydroelectric power potential in the country from its numerous rivers. Large swaths of the Alaskan coastline offer wind and geothermal energy potential as well. Alaska's economy depends heavily on increasingly expensive diesel fuel for heating, transportation, electric power and light. Although wind and hydroelectric power are abundant and underdeveloped, proposals for statewide energy systems (e.g. with special [[single-wire earth return#Use in interties|low-cost electric interties]]) were judged uneconomical (at the time of the report, 2001) due to low (less than 50¢/gal) fuel prices, long distances and low population. The cost of a gallon of gas in urban Alaska today is usually thirty to sixty cents higher than the national average; prices in rural areas are generally significantly higher but vary widely depending on transportation costs, seasonal usage peaks, nearby petroleum development infrastructure and many other factors. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Economy",
"Energy",
"Permanent Fund"
] | The [[Alaska Permanent Fund]] is a constitutionally authorized appropriation of oil revenues, established by voters in 1976 to manage a surplus in state petroleum revenues from oil, largely in anticipation of the then recently constructed [[Trans-Alaska Pipeline System]]. The fund was originally proposed by Governor [[Keith Harvey Miller|Keith Miller]] on the eve of the 1969 Prudhoe Bay lease sale, out of fear that the legislature would spend the entire proceeds of the sale (which amounted to $900 million) at once. It was later championed by Governor [[Jay Hammond]] and [[Kenai, Alaska|Kenai]] [[Alaska House of Representatives|state representative]] Hugh Malone. It has served as an attractive political prospect ever since, diverting revenues which would normally be deposited into the general fund. The [[Alaska Constitution]] was written so as to discourage dedicating state funds for a particular purpose. The Permanent Fund has become the rare exception to this, mostly due to the political climate of distrust existing during the time of its creation. From its initial principal of $734,000, the fund has grown to $50 billion as a result of oil royalties and capital investment programs. Most if not all the principal is invested conservatively outside Alaska. This has led to frequent calls by Alaskan politicians for the Fund to make investments within Alaska, though such a stance has never gained momentum. Starting in 1982, dividends from the fund's annual growth have been paid out each year to eligible Alaskans, ranging from an initial $1,000 in 1982 (equal to three years' payout, as the distribution of payments was held up in a lawsuit over the distribution scheme) to $3,269 in 2008 (which included a one-time $1,200 "Resource Rebate"). Every year, the state legislature takes out 8% from the earnings, puts 3% back into the principal for inflation proofing, and the remaining 5% is distributed to all qualifying Alaskans. To qualify for the Permanent Fund Dividend, one must have lived in the state for a minimum of 12 months, maintain constant residency subject to allowable absences, and not be subject to court judgments or criminal convictions which fall under various disqualifying classifications or may subject the payment amount to civil garnishment. The Permanent Fund is often considered to be one of the leading examples of a "[[Basic income]]" policy in the world. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Economy",
"Cost of living"
] | The cost of goods in Alaska has long been higher than in the contiguous 48 states. Federal government employees, particularly [[United States Postal Service]] (USPS) workers and active-duty military members, receive a Cost of Living Allowance usually set at 25% of base pay because, while the cost of living has gone down, it is still one of the highest in the country. Rural Alaska suffers from extremely high prices for food and consumer goods compared to the rest of the country, due to the relatively limited transportation infrastructure. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Economy",
"Agriculture and fishing"
] | Due to the northern climate and short growing season, relatively little farming occurs in Alaska. Most farms are in either the [[Matanuska Valley]], about northeast of [[Anchorage]], or on the [[Kenai Peninsula]], about southwest of Anchorage. The short 100-day growing season limits the crops that can be grown, but the long sunny summer days make for productive growing seasons. The primary crops are potatoes, carrots, lettuce, and cabbage. The [[Tanana Valley]] is another notable agricultural locus, especially the [[Delta Junction, Alaska|Delta Junction]] area, about southeast of Fairbanks, with a sizable concentration of farms growing agronomic crops; these farms mostly lie north and east of [[Fort Greely]]. This area was largely set aside and developed under a state program spearheaded by Hammond during his second term as governor. Delta-area crops consist predominantly of barley and hay. West of Fairbanks lies another concentration of small farms catering to restaurants, the hotel and tourist industry, and [[community-supported agriculture]]. Alaskan agriculture has experienced a surge in growth of [[market gardener]], small farms and [[farmers' market]] in recent years, with the highest percentage increase (46%) in the nation in growth in farmers' markets in 2011, compared to 17% nationwide. The [[peony]] industry has also taken off, as the growing season allows farmers to harvest during a gap in supply elsewhere in the world, thereby filling a niche in the flower market. Alaska, with no counties and lacks county fairs. However, a small assortment of state and local fairs (with the [[Alaska State Fair]] in [[Palmer, Alaska|Palmer]] the largest), are held mostly in the late summer. The fairs are mostly located in communities with historic or current agricultural activity, and feature local farmers exhibiting produce in addition to more high-profile commercial activities such as carnival rides, concerts and food. "Alaska Grown" is used as an agricultural slogan. Alaska has an abundance of seafood, with the primary fisheries in the Bering Sea and the North Pacific. Seafood is one of the few food items that is often cheaper within the state than outside it. Many Alaskans take advantage of salmon seasons to harvest portions of their household diet while fishing for subsistence, as well as sport. This includes fish taken by hook, net or wheel. Hunting for subsistence, primarily [[caribou]], [[moose]], and [[Dall sheep]] is still common in the state, particularly in remote [[The Bush (Alaska)|Bush]] communities. An example of a traditional native food is [[Akutaq]], the Eskimo ice cream, which can consist of reindeer fat, seal oil, dried fish meat and local berries. Alaska's reindeer herding is concentrated on [[Seward Peninsula]], where wild caribou can be prevented from mingling and migrating with the domesticated reindeer. | 624 | Alaska | [
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"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Economy",
"Agriculture and fishing"
] | Most food in Alaska is transported into the state from [[Outside (Alaska)|"Outside"]] (the other 49 US states), and shipping costs make food in the cities relatively expensive. In rural areas, subsistence hunting and gathering is an essential activity because imported food is prohibitively expensive. Although most small towns and villages in Alaska lie along the coastline, the cost of importing food to remote villages can be high, because of the terrain and difficult road conditions, which change dramatically, due to varying climate and precipitation changes. The cost of transport can reach as high as 50¢ per pound ($1.10/kg) or more in some remote areas, during the most difficult times, if these locations can be reached at all during such inclement weather and terrain conditions. The cost of delivering a of milk is about $3.50 in many villages where per capita income can be $20,000 or less. Fuel cost per gallon is routinely twenty to thirty cents higher than the contiguous United States average, with only Hawaii having higher prices. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Transportation",
"Roads"
] | Alaska has few road connections compared to the rest of the U.S. The state's road system, covering a relatively small area of the state, linking the central population centers and the [[Alaska Highway]], the principal route out of the state through Canada. The state capital, Juneau, is not accessible by road, only a car ferry; this has spurred debate over decades about moving the capital to a city on the road system, or building a road connection from [[Haines, Alaska|Haines]]. The western part of Alaska has no road system connecting the communities with the rest of Alaska. The [[Interstate Highways in Alaska]] consists of a total of . One unique feature of the Alaska Highway system is the [[Anton Anderson Memorial Tunnel]], an active [[Alaska Railroad]] tunnel recently upgraded to provide a paved roadway link with the isolated community of [[Whittier, Alaska|Whittier]] on [[Prince William Sound]] to the [[Seward Highway]] about southeast of Anchorage at [[Portage, Alaska|Portage]]. At , the tunnel was the longest road tunnel in North America until 2007. The tunnel is the longest combination [[List of road-rail tunnels|road and rail tunnel]] in North America. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Transportation",
"Rail"
] | Built around 1915, the [[Alaska Railroad]] (ARR) played a key role in the development of Alaska through the 20th century. It links north Pacific shipping through providing critical infrastructure with tracks that run from [[Seward, Alaska|Seward]] to [[Interior Alaska]] by way of [[South Central Alaska]], passing through Anchorage, [[Eklutna]], Wasilla, [[Talkeetna, Alaska|Talkeetna]], [[Denali]], and Fairbanks, with spurs to [[Whittier, Alaska|Whittier]], [[Palmer, Alaska|Palmer]] and [[North Pole, Alaska|North Pole]]. The cities, towns, villages, and region served by ARR tracks are known statewide as "The Railbelt". In recent years, the ever-improving paved highway system began to eclipse the railroad's importance in Alaska's economy. The railroad played a vital role in Alaska's development, moving freight into Alaska while transporting natural resources southward, such as coal from the Usibelli coal mine near [[Healy, Alaska|Healy]] to Seward and gravel from the [[Matanuska Valley]] to Anchorage. It is well known for its summertime tour passenger service. The Alaska Railroad was one of the last railroads in North America to use [[caboose]] in regular service and still uses them on some gravel trains. It continues to offer one of the last [[Request stop|flag stop]] routes in the country. A stretch of about of track along an area north of Talkeetna remains inaccessible by road; the railroad provides the only transportation to rural homes and cabins in the area. Until construction of the Parks Highway in the 1970s, the railroad provided the only land access to most of the region along its entire route. In northern Southeast Alaska, the [[White Pass and Yukon Route]] also partly runs through the state from [[Skagway, Alaska|Skagway]] northwards into Canada (British Columbia and Yukon Territory), crossing the border at [[White Pass]] Summit. This line is now mainly used by tourists, often arriving by cruise liner at Skagway. It was featured in the 1983 [[BBC]] television series ''[[Great Little Railways]].'' The Alaska Rail network is not connected to Outside. (The nearest link to the North American railway network is the northwest terminus of the [[Canadian National Railway]] at [[Prince Rupert, British Columbia]], several hundred miles to the southeast.) In 2000, the U.S. Congress authorized $6 million to study the feasibility of a rail link between Alaska, Canada, and the lower 48. Some private companies provides [[car float]] service between [[Whittier, Alaska|Whittier]] and [[Seattle]]. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Transportation",
"Marine transport"
] | Many cities, towns and villages in the state do not have road or highway access; the only modes of access involve travel by air, river, or the sea. Alaska's well-developed state-owned ferry system (known as the [[Alaska Marine Highway]]) serves the cities of [[Southeast Alaska|southeast]], the Gulf Coast and the Alaska Peninsula. The ferries transport vehicles as well as passengers. The system also operates a ferry service from [[Bellingham, Washington]] and [[Prince Rupert, British Columbia]], in Canada through the [[Inside Passage]] to [[Skagway, Alaska|Skagway]]. The [[Inter-Island Ferry Authority]] also serves as an important marine link for many communities in the [[Prince of Wales Island (Alaska)|Prince of Wales Island]] region of Southeast and works in concert with the Alaska Marine Highway. In recent years, cruise lines have created a summertime tourism market, mainly connecting the Pacific Northwest to Southeast Alaska and, to a lesser degree, towns along Alaska's gulf coast. The population of [[Ketchikan, Alaska|Ketchikan]] for example fluctuates dramatically on many days—up to four large cruise ships can dock there at the same time. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Transportation",
"Air transport"
] | Cities not served by road, sea, or river can be reached only by air, foot, dogsled, or snowmachine, accounting for Alaska's extremely well developed [[Alaskan Bush|bush]] air services—an Alaskan novelty. Anchorage and, to a lesser extent Fairbanks, is served by [[Ted Stevens Anchorage International Airport#Airlines and destinations|many major airlines]]. Because of limited highway access, air travel remains the most efficient form of transportation in and out of the state. Anchorage recently completed extensive remodeling and construction at [[Ted Stevens Anchorage International Airport]] to help accommodate the upsurge in tourism (in 2012–2013, Alaska received almost two million visitors). Regular flights to most villages and towns within the state that are commercially viable are challenging to provide, so they are heavily subsidized by the federal government through the [[Essential Air Service]] program. [[Alaska Airlines]] is the only major airline offering in-state travel with jet service (sometimes in combination cargo and passenger [[Boeing 737]]-400s) from Anchorage and [[Fairbanks International Airport|Fairbanks]] to regional hubs like [[Bethel, Alaska|Bethel]], [[Nome, Alaska|Nome]], [[Kotzebue, Alaska|Kotzebue]], [[Dillingham, Alaska|Dillingham]], [[Kodiak, Alaska|Kodiak]], and other larger communities as well as to major Southeast and Alaska Peninsula communities. The bulk of remaining commercial flight offerings come from small regional commuter airlines such as [[Ravn Alaska]], [[PenAir]], and [[Frontier Flying Service]]. The smallest towns and villages must rely on scheduled or chartered bush flying services using general aviation aircraft such as the [[Cessna Caravan]], the most popular aircraft in use in the state. Much of this service can be attributed to the Alaska bypass mail program which subsidizes bulk mail delivery to Alaskan rural communities. The program requires 70% of that subsidy to go to carriers who offer passenger service to the communities. Many communities have small air taxi services. These operations originated from the demand for customized transport to remote areas. Perhaps the most quintessentially Alaskan plane is the bush seaplane. The world's busiest seaplane base is [[Lake Hood Seaplane Base|Lake Hood]], located next to Ted Stevens Anchorage International Airport, where flights bound for remote villages without an airstrip carry passengers, cargo, and many items from stores and warehouse clubs. In 2006 Alaska had the highest number of pilots per capita of any U.S. state. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Transportation",
"Other transport"
] | Another Alaskan transportation method is the [[dogsled]]. In modern times (that is, any time after the mid-late 1920s), dog [[mushing]] is more of a sport than a true means of transportation. Various races are held around the state, but the best known is the [[Iditarod Trail Sled Dog Race]], a trail from Anchorage to Nome (although the distance varies from year to year, the official distance is set at ). The race commemorates the famous [[1925 serum run to Nome]] in which mushers and dogs like [[Togo (dog)|Togo]] and [[Balto]] took much-needed medicine to the [[diphtheria]]-stricken community of [[Nome, Alaska|Nome]] when all other means of transportation had failed. Mushers from all over the world come to Anchorage each March to compete for cash, prizes, and prestige. The "Serum Run" is another sled dog race that more accurately follows the route of the famous 1925 relay, leaving from the community of [[Nenana, Alaska|Nenana]] (southwest of Fairbanks) to Nome. In areas not served by road or rail, primary transportation in summer is by [[all-terrain vehicle]] and in winter by [[snowmobile]] or "snow machine", as it is commonly referred to in Alaska. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Transportation",
"Data transport"
] | Alaska's internet and other data transport systems are provided largely through the two major telecommunications companies: [[GCI (company)|GCI]] and [[Alaska Communications]]. GCI owns and operates what it calls the Alaska United Fiber Optic system and, as of late 2011, Alaska Communications advertised that it has "two fiber optic paths to the lower 48 and two more across Alaska. In January 2011, it was reported that a $1 billion project to connect Asia and rural Alaska was being planned, aided in part by $350 million in stimulus from the federal government. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Law and government",
"State government"
] | Like all other U.S. states, Alaska is governed as a republic, with three [[separation of powers|branches of government]]: an [[executive branch]] consisting of the [[governor of Alaska]] and his or her appointees which head executive departments; a [[legislative branch]] consisting of the [[Alaska House of Representatives]] and [[Alaska Senate]]; and a [[judicial branch]] consisting of the [[Alaska Supreme Court]] and lower courts. The state of Alaska employs approximately 16,000 people statewide. The [[Alaska Legislature]] consists of a 40-member [[Alaska House of Representatives|House of Representatives]] and a 20-member [[Alaska Senate|Senate]]. Senators serve four-year terms and House members two. The [[governor of Alaska]] serves four-year terms. The [[List of Lieutenant Governors of Alaska|lieutenant governor]] runs separately from the governor in the [[Primary election|primaries]], but during the general election, the nominee for governor and nominee for lieutenant governor run together on the same ticket. Alaska's court system has four levels: the [[Alaska Supreme Court]], the [[Alaska Court of Appeals]], the superior courts and the district courts. The superior and district courts are [[trial court]]. Superior courts are courts of general jurisdiction, while district courts hear only certain types of cases, including misdemeanor criminal cases and civil cases valued up to $100,000. The Supreme Court and the Court of Appeals are [[appellate court]]. The Court of Appeals is required to hear appeals from certain lower-court decisions, including those regarding criminal prosecutions, juvenile delinquency, and [[habeas corpus]]. The Supreme Court hears civil appeals and may in its discretion hear criminal appeals. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Law and government",
"State politics"
] | Although in its early years of statehood Alaska was a [[Democratic Party (United States)|Democratic]] state, since the early 1970s it has been characterized as [[Republican Party (United States)|Republican]]-leaning. Local political communities have often worked on issues related to land use development, fishing, tourism, and individual rights. [[Alaska Natives]], while organized in and around their communities, have been active within the [[Alaska Native Regional Corporations|Native corporations]]. These have been given ownership over large tracts of land, which require stewardship. Alaska was formerly the only state in which possession of one ounce or less of marijuana in one's home was completely legal under state law, though the federal law remains in force. The state has an independence movement favoring a vote on secession from the United States, with the [[Alaskan Independence Party]]. Six [[Republican Party (United States)|Republicans]] and four [[Democratic Party (United States)|Democrats]] have served as governor of Alaska. In addition, Republican governor [[Wally Hickel]] was elected to the office for a second term in 1990 after leaving the Republican party and briefly joining the Alaskan Independence Party ticket just long enough to be reelected. He officially rejoined the Republican party in 1994. Alaska's [[2014 Alaska Measure 2|voter initiative making marijuana legal]] took effect on February 24, 2015, placing Alaska alongside Colorado and Washington as the first three U.S. states where recreational marijuana is legal. The new law means people over 21 can consume small amounts of pot. The first legal marijuana store opened in Valdez in October 2016. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Law and government",
"Taxes"
] | To finance state government operations, Alaska depends primarily on petroleum revenues and federal subsidies. This allows it to have the lowest individual tax burden in the United States. It is one of five states with no [[sales tax]], one of seven states with no individual [[income tax]], and—along with [[New Hampshire]]—one of two that has neither. The Department of Revenue Tax Division reports regularly on the state's revenue sources. The Department also issues an annual summary of its operations, including new state laws that directly affect the tax division. In 2014 the [[Tax Foundation]] ranked Alaska as having the fourth most "business friendly" tax policy, behind only [[Wyoming]], [[South Dakota]], and [[Nevada]]. While Alaska has no state sales tax, 89 municipalities collect a local sales tax, from 1.0 to 7.5%, typically 3–5%. Other local taxes levied include raw fish taxes, hotel, motel, and bed-and-breakfast 'bed' taxes, [[severance tax]], liquor and tobacco taxes, gaming (pull tabs) taxes, tire taxes and fuel transfer taxes. A part of the revenue collected from certain state taxes and license fees (such as petroleum, aviation motor fuel, telephone cooperative) is shared with municipalities in Alaska. The fall in oil prices after the [[Hydraulic fracturing in the United States|fracking boom]] in the early 2010s has decimated Alaska's state treasury, which has historically received about 85 percent of its revenue from taxes and fees imposed on oil and gas companies. The state government has had to drastically reduce its budget, and has brought its budget shortfall from over $2 billion in 2016 to under $500 million by 2018. In 2020, Alaska's state government budget was $4.8 billion, while projected government revenues were only $4.5 billion. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Law and government",
"Federal politics"
] | Alaska regularly supports [[Republican Party (United States)|Republicans]] in presidential elections and has done so since statehood. Republicans have won the state's [[Electoral College (United States)|electoral college]] votes in all but one election that it has participated in ([[1964 United States presidential election|1964]]). No state has voted for a [[Democratic Party (United States)|Democratic]] presidential candidate fewer times. Alaska was carried by Democratic nominee [[Lyndon B. Johnson]] during his landslide election in [[1964 United States presidential election|1964]], while the [[1960 United States presidential election|1960]] and [[1968 United States presidential election|1968]] elections were close. Since [[1972 United States presidential election|1972]], however, Republicans have carried the state by large margins. In [[2008 United States presidential election|2008]], Republican [[John McCain]] defeated Democrat [[Barack Obama]] in Alaska, 59.49% to 37.83%. McCain's running mate was [[Sarah Palin]], the state's governor and the first Alaskan on a major party ticket. Obama lost Alaska again in [[2012 United States presidential election|2012]], but he captured 40% of the state's vote in that election, making him the first Democrat to do so since 1968. The [[The Bush (Alaska)|Alaska Bush]], central Juneau, midtown and downtown Anchorage, and the areas surrounding the [[University of Alaska Fairbanks]] campus and Ester have been strongholds of the Democratic Party. The Matanuska-Susitna Borough, the majority of Fairbanks (including North Pole and the military base), and South Anchorage typically have the strongest Republican showing. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Law and government",
"Elections"
] | In the [[2020 Alaska elections|2020 election]] cycle, Alaskan voters approved Ballot Measure 2. Bipartisan coalitions led the campaigns for and against the bill. The measure passed by a margin of 1.1%, or about 4,000 votes. Supporters of the measure claim that it will reduce "[[dark money]]" in Alaskan elections by requiring anyone giving over $2,000 to a campaign to disclose the true source of such contributions and all intermediaries. The measure also establishes [[Nonpartisan blanket primary|non-partisan blanket primaries]] for statewide elections (like in [[Washington (state)#Elections|Washington state]] and [[California#Government_and_politics|California]]) and [[ranked-choice voting]] (like in [[Maine#Politics|Maine]]). Alaska is the third state with [[Jungle primary|jungle primaries]] for all statewide races, the second state with [[ranked voting]], and the only state with both. The first race to use the new system of elections will be the [[2022 United States Senate election in Alaska|2022 Senate election]] in which Lisa Murkowski will run for re-election. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Cities, towns and boroughs"
] | Alaska is not divided into [[County (United States)|counties]], as most of the other U.S. states, but it is divided into ''[[List of boroughs and census areas in Alaska|boroughs]]''. Many of the more densely populated parts of the state are part of Alaska's 16 boroughs, which function somewhat similarly to counties in other states. However, unlike county-equivalents in the other 49 states, the boroughs do not cover the entire land area of the state. The area not part of any borough is referred to as the [[Unorganized Borough, Alaska|Unorganized Borough]]. The Unorganized Borough has no government of its own, but the [[U.S. Census Bureau]] in cooperation with the state divided the Unorganized Borough into 11 [[census area]] solely for the purposes of statistical analysis and presentation. A ''recording district'' is a mechanism for management of the [[public record]] in Alaska. The state is divided into 34 recording districts which are centrally administered under a State [[recorder of deeds|Recorder]]. All recording districts use the same acceptance criteria, fee schedule, etc., for accepting documents into the public record. Whereas many U.S. states use a three-tiered system of decentralization—state/county/township—most of Alaska uses only two tiers—state/borough. Owing to the low population density, most of the land is located in the [[Unorganized Borough]]. As the name implies, it has no intermediate borough government but is administered directly by the state government. In 2000, 57.71% of Alaska's area has this status, with 13.05% of the population. Anchorage merged the city government with the Greater Anchorage Area Borough in 1975 to form the Municipality of Anchorage, containing the city proper and the communities of Eagle River, Chugiak, Peters Creek, Girdwood, Bird, and Indian. Fairbanks has a separate borough (the [[Fairbanks North Star Borough]]) and municipality (the City of Fairbanks). The state's most populous city is [[Anchorage, Alaska|Anchorage]], home to 278,700 people in 2006, 225,744 of whom live in the urbanized area. The richest [[Alaska locations by per capita income|location in Alaska by per capita income]] is [[Denali Borough, Alaska|Denali]] ($42,245). [[Yakutat City]], Sitka, Juneau, and Anchorage are the four [[List of U.S. cities by area|largest cities in the U.S. by area]]. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Cities, towns and boroughs",
"Cities and census-designated places (by population)"
] | As reflected in the [[2010 United States Census]], Alaska has a total of 355 incorporated cities and [[census-designated place]] (CDPs). The tally of cities includes four unified municipalities, essentially the equivalent of a [[consolidated city–county]]. The majority of these communities are located in the rural expanse of Alaska known as "[[The Bush (Alaska)|The Bush]]" and are unconnected to the contiguous North American road network. The table at the bottom of this section lists the 100 largest cities and census-designated places in Alaska, in population order. Of Alaska's 2010 Census population figure of 710,231, 20,429 people, or 2.88% of the population, did not live in an incorporated city or census-designated place. Approximately three-quarters of that figure were people who live in urban and suburban neighborhoods on the outskirts of the city limits of Ketchikan, Kodiak, Palmer and Wasilla. CDPs have not been established for these areas by the [[United States Census Bureau]], except that seven CDPs were established for the Ketchikan-area neighborhoods in the [[1980 United States Census|1980 Census]] (Clover Pass, Herring Cove, Ketchikan East, Mountain Point, North [[Tongass Highway]], [[Pennock Island]] and [[Saxman, Alaska|Saxman]] East), but have not been used since. The remaining population was scattered throughout Alaska, both within organized boroughs and in the [[Unorganized Borough]], in largely remote areas. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Education"
] | The [[Alaska Department of Education and Early Development]] administers many [[List of school districts in Alaska|school districts]] in Alaska. In addition, the state operates a boarding school, [[Mt. Edgecumbe High School]] in [[Sitka, Alaska|Sitka]], and provides partial funding for other boarding schools, including [[Nenana Student Living Center]] in [[Nenana, Alaska|Nenana]] and The Galena Interior Learning Academy in [[Galena, Alaska|Galena]]. There are more than a dozen [[List of colleges and universities in Alaska|colleges and universities in Alaska]]. Accredited universities in Alaska include the [[University of Alaska Anchorage]], [[University of Alaska Fairbanks]], [[University of Alaska Southeast]], and [[Alaska Pacific University]]. Alaska is the only state that has no institutions that are part of [[NCAA Division I]]. The Alaska Department of Labor and Workforce Development operates AVTEC, Alaska's Institute of Technology. Campuses in Seward and Anchorage offer one-week to 11-month training programs in areas as diverse as Information Technology, Welding, Nursing, and Mechanics. Alaska has had a problem with a "[[brain drain]]". Many of its young people, including most of the highest academic achievers, leave the state after high school graduation and do not return. , Alaska did not have a [[Legal education in Alaska|law school]] or medical school. The [[University of Alaska]] has attempted to combat this by offering partial four-year scholarships to the top 10% of Alaska high school graduates, via the Alaska Scholars Program. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Public health and public safety"
] | The [[Alaska State Troopers]] are Alaska's statewide police force. They have a long and storied history, but were not an official organization until 1941. Before the force was officially organized, law enforcement in Alaska was handled by various federal agencies. Larger towns usually have their own local police and some villages rely on "Public Safety Officers" who have police training but do not carry firearms. In much of the state, the troopers serve as the only police force available. In addition to enforcing traffic and criminal law, wildlife Troopers enforce hunting and fishing regulations. Due to the varied terrain and wide scope of the Troopers' duties, they employ a wide variety of land, air, and water patrol vehicles. Many rural communities in Alaska are considered "dry", having outlawed the importation of alcoholic beverages. Suicide rates for rural residents are higher than urban. [[Domestic abuse]] and other violent crimes are also at high levels in the state; this is in part linked to alcohol abuse. Alaska has the highest rate of sexual assault in the nation, especially in rural areas. The average age of sexually assaulted victims is 16 years old. In four out of five cases, the suspects were relatives, friends or acquaintances. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Culture"
] | Some of Alaska's popular annual events are the [[Iditarod Trail Sled Dog Race]] from Anchorage to Nome, World Ice Art Championships in Fairbanks, the Blueberry Festival and Alaska Hummingbird Festival in [[Ketchikan, Alaska|Ketchikan]], the Sitka Whale Fest, and the Stikine River Garnet Fest in [[Wrangell, Alaska|Wrangell]]. The [[Stikine River]] attracts the largest springtime concentration of [[American bald eagle]] in the world. The [[Alaska Native Heritage Center]] celebrates the rich heritage of Alaska's 11 cultural groups. Their purpose is to encourage cross-cultural exchanges among all people and enhance self-esteem among Native people. The [[Alaska Native Arts Foundation]] promotes and markets Native art from all regions and cultures in the State, using the internet. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Culture",
"Music"
] | Influences on music in Alaska include the traditional music of Alaska Natives as well as folk music brought by later immigrants from Russia and Europe. Prominent musicians from Alaska include singer [[Jewel (singer)|Jewel]], traditional Aleut flautist [[Mary Youngblood]], folk singer-songwriter [[Libby Roderick]], Christian music singer-songwriter [[Lincoln Brewster]], metal/post hardcore band [[36 Crazyfists]] and the groups [[Pamyua]] and [[Portugal. The Man]]. There are many established music festivals in Alaska, including the [[Alaska Folk Festival]], the Fairbanks Summer Arts Festival the Anchorage Folk Festival, the [[Athabascan Old-Time Fiddling Festival]], the Sitka Jazz Festival, and the [[Sitka Summer Music Festival]]. The most prominent orchestra in Alaska is the [[Anchorage Symphony Orchestra]], though the Fairbanks Symphony Orchestra and [[Juneau Symphony]] are also notable. The [[Anchorage Opera]] is currently the state's only professional opera company, though there are several volunteer and semi-professional organizations in the state as well. The official [[List of U.S. state songs|state song]] of Alaska is "[[Alaska's Flag]]", which was adopted in 1955; it celebrates the [[flag of Alaska]]. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"Culture",
"Alaska in film and on television"
] | Alaska's first independent picture entirely made in Alaska was ''[[The Chechahcos]]'', produced by Alaskan businessman [[Austin E. Lathrop]] and filmed in and around Anchorage. Released in 1924 by the Alaska Moving Picture Corporation, it was the only film the company made. One of the most prominent movies filmed in Alaska is [[Metro-Goldwyn-Mayer|MGM]]'s ''[[Eskimo/Mala The Magnificent]]'', starring Alaska Native [[Ray Mala]]. In 1932 an expedition set out from [[MGM]]'s studios in Hollywood to Alaska to film what was then billed as "The Biggest Picture Ever Made". Upon arriving in Alaska, they set up "Camp Hollywood" in Northwest Alaska, where they lived during the duration of the filming. [[Louis B. Mayer]] spared no expense in spite of the remote location, going so far as to hire the chef from the [[Roosevelt Hotel (Hollywood)|Hotel Roosevelt]] in Hollywood to prepare meals. When ''Eskimo'' premiered at the [[Astor Theatre, New York City|Astor Theatre]] in New York City, the studio received the largest amount of feedback in its history. ''Eskimo'' was critically acclaimed and released worldwide; as a result, Mala became an international movie star. ''Eskimo'' won the first Oscar for [[Academy Award for Best Film Editing|Best Film Editing]] at the Academy Awards, and showcased and preserved aspects of [[Inupiat people|Inupiat]] culture on film. The 1983 Disney movie ''[[Never Cry Wolf (film)|Never Cry Wolf]]'' was at least partially shot in Alaska. The 1991 film ''[[White Fang (1991 film)|White Fang]]'', based on [[Jack London]]'s 1906 novel and starring [[Ethan Hawke]], was filmed in and around [[Haines, Alaska|Haines]]. [[Steven Seagal]]'s 1994 ''[[On Deadly Ground]]'', starring [[Michael Caine]], was filmed in part at the [[Worthington Glacier]] near [[Valdez, Alaska|Valdez]]. The 1999 [[John Sayles]] film ''[[Limbo (1999 film)|Limbo]]'', starring [[David Strathairn]], [[Mary Elizabeth Mastrantonio]], and [[Kris Kristofferson]], was filmed in Juneau. The psychological thriller ''[[Insomnia (2002 film)|Insomnia]]'', starring [[Al Pacino]] and [[Robin Williams]], was shot in Canada, but was set in Alaska. The 2007 film directed by Sean Penn, ''[[Into the Wild (film)|Into The Wild]]'', was partially filmed and set in Alaska. The film, which is based on the novel of the same name, follows the adventures of [[Christopher McCandless]], who died in a remote abandoned bus along the [[Stampede Trail]] west of [[Healy, Alaska|Healy]] in 1992. Many films and television shows set in Alaska are not filmed there; for example, ''[[Northern Exposure]]'', set in the fictional town of Cicely, Alaska, was filmed in [[Roslyn, Washington]]. The 2007 horror feature ''[[30 Days of Night (film)|30 Days of Night]]'' is set in [[Utqiaġvik, Alaska|Barrow, Alaska]], but was filmed in New Zealand. Many reality television shows are filmed in Alaska. In 2011 the ''Anchorage Daily News'' found ten set in the state. In 2020 [[Netflix]] published [[Win the Wilderness]], a reality TV series produced for [[BBC Two]]. | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[
"State symbols"
] | (-) State motto: North to the Future (-) Nicknames: "The Last Frontier" or "Land of the Midnight Sun" or "Seward's Icebox" (-) State bird: [[willow ptarmigan]], adopted by the Territorial Legislature in 1955. It is a small () Arctic grouse that lives among willows and on open tundra and muskeg. Plumage is brown in summer, changing to white in winter. The willow ptarmigan is common in much of Alaska. (-) State fish: [[Chinook salmon|king salmon]], adopted 1962. (-) State flower: wild/native [[forget-me-not]], adopted by the Territorial Legislature in 1917. It is a perennial found throughout Alaska, from Hyder to the Arctic Coast, and west to the Aleutians. (-) State fossil: [[woolly mammoth]], adopted 1986. (-) State gem: [[nephrite|jade]], adopted 1968. (-) State insect: [[Four-spotted chaser|four-spot skimmer]] dragonfly, adopted 1995. (-) State land mammal: [[moose]], adopted 1998. (-) State marine mammal: [[bowhead whale]], adopted 1983. (-) State mineral: gold, adopted 1968. (-) State song: "[[Alaska's Flag]]" (-) State sport: [[Mushing|dog mushing]], adopted 1972. (-) State tree: [[Sitka spruce]], adopted 1962. (-) State dog: [[Alaskan Malamute]], adopted 2010. (-) State soil: [[Tanana (soil)|Tanana]], unknown when adopted . | 624 | Alaska | [
"Alaska",
"Arctic Ocean",
"Former Russian colonies",
"States and territories established in 1959",
"States of the United States",
"States of the West Coast of the United States",
"U.S. states with multiple time zones",
"1959 establishments in the United States",
"Western United States"
] | [
"Index of Alaska-related articles",
"Outline of Alaska"
] |
[] | '''Agriculture''' is the science, art and practice of cultivating plants and livestock. Agriculture was the key development in the rise of [[sedentism|sedentary]] [[human civilization]], whereby farming of [[domestication|domesticated]] species created food [[economic surplus|surpluses]] that enabled people to live in cities. The [[history of agriculture]] began thousands of years ago. After gathering wild grains beginning at least 105,000 years ago, nascent farmers began to plant them around 11,500 years ago. Pigs, sheep, and cattle were domesticated over 10,000 years ago. Plants were independently cultivated in at least 11 regions of the world. [[Industrial agriculture]] based on large-scale [[monoculture]] in the twentieth century came to dominate agricultural output, though about 2 billion people still depended on [[subsistence agriculture]]. Modern [[agronomy]], [[plant breeding]], [[agrochemical]] such as [[pesticide]] and [[fertilizer]], and technological developments have sharply increased [[crop]] yields, while causing [[Environmental impact of agriculture|widespread ecological and environmental damage]]. [[Selective breeding]] and modern practices in [[animal husbandry]] have similarly increased the output of meat, but have raised concerns about [[animal welfare]] and environmental damage. Environmental issues include contributions to [[global warming]], depletion of [[aquifer]], [[deforestation]], [[antibiotic resistance]], and [[growth hormone]] in [[industrial meat production]]. Agriculture is also very sensitive to [[environmental degradation]], such as [[biodiversity loss]], [[desertification]], [[soil degradation]] and [[Climate change and agriculture|global warming]], which cause decrease in crop yield. [[Genetically modified organism]] are widely used, although some are banned in certain countries. The major agricultural products can be broadly grouped into foods, fibers, [[fuel]] and [[raw material]] (such as [[natural rubber|rubber]]). Food classes include cereals ([[grains]]), [[vegetable]], fruits, [[cooking oil|oils]], meat, milk, [[edible mushroom|fungi]] and [[eggs as food|eggs]]. Over one-third of the world's workers are employed in agriculture, second only to the [[service sector]], although in recent decades, the global trend of a decreasing number of agricultural workers continues, especially in developing countries where [[smallholding]] is being overtaken by industrial agriculture and mechanization. Creating global [[sustainable food system]] which provides [[food security]] with [[sustainable agriculture]] practices is an international policy priority articulated in [[Sustainable Development Goal 2|Sustainable Development Goal 2: "Zero hunger"]], adopted by the [[United Nations]] in 2015. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Etymology and scope"
] | The word ''agriculture'' is a late [[Middle English]] adaptation of Latin ''agricultūra'', from ''ager'', "field", and ''cultūra'', "[[Tillage|cultivation]]" or "growing". While agriculture usually refers to human activities, certain species of [[Attine ants|ant]], [[termite]] and [[ambrosia beetle|beetle]] have been cultivating crops for up to 60 million years. Agriculture is defined with varying scopes, in its broadest sense using natural resources to "produce commodities which maintain life, including food, fiber, forest products, horticultural crops, and their related services". Thus defined, it includes [[arable farming]], [[horticulture]], [[animal husbandry]] and [[forestry]], but horticulture and forestry are in practice often excluded. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"History",
"Origins"
] | The development of agriculture enabled the human population to grow many times larger than could be sustained by [[hunter-gatherer|hunting and gathering]]. Agriculture began independently in different parts of the globe, and included a diverse range of [[taxa]], in at least 11 separate [[centers of origin|centres of origin]]. Wild grains were collected and eaten from at least 105,000 years ago. From around 11,500 years ago, the eight [[Neolithic founder crops]], [[emmer wheat|emmer]] and [[einkorn wheat]], hulled [[barley]], [[pea]], [[lentil]], [[Vicia ervilia|bitter vetch]], [[chick pea]] and [[flax]] were cultivated in the [[Levant]]. Rice was domesticated in China between 11,500 and 6,200 BC with the earliest known cultivation from 5,700 BC, followed by [[mung bean|mung]], [[soy]] and [[Azuki bean|azuki]] beans. Sheep were domesticated in [[Mesopotamia]] between 13,000 and 11,000 years ago. Cattle were domesticated from the wild [[aurochs]] in the areas of modern Turkey and Pakistan some 10,500 years ago. [[Domestic pig|Pig production]] emerged in Eurasia, including Europe, East Asia and Southwest Asia, where [[wild boar]] were first domesticated about 10,500 years ago. In the [[Andes]] of South America, the potato was domesticated between 10,000 and 7,000 years ago, along with beans, [[coca]], [[llama]], [[alpaca]], and [[guinea pig]]. [[Sugarcane]] and some [[List of root vegetables|root vegetables]] were domesticated in [[New Guinea]] around 9,000 years ago. [[Sorghum]] was domesticated in the [[Sahel]] region of Africa by 7,000 years ago. Cotton was domesticated in [[Peru]] by 5,600 years ago, and was independently domesticated in Eurasia. [[Agriculture in Mesoamerica|In Mesoamerica]], wild [[teosinte]] was bred into maize by 6,000 years ago. Scholars have offered multiple hypotheses to explain the historical origins of agriculture. Studies of the transition from [[hunter-gatherer]] to agricultural societies indicate an initial period of intensification and increasing [[sedentism]]; examples are the [[Natufian culture]] in the [[Levant]], and the Early Chinese Neolithic in China. Then, wild stands that had previously been harvested started to be planted, and gradually came to be domesticated. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"History",
"Civilizations"
] | In Eurasia, the [[Sumer]] started to live in villages from about 8,000 BC, relying on the [[Tigris]] and [[Euphrates]] rivers and a canal system for irrigation. Ploughs appear in [[pictograph]] around 3,000 BC; seed-ploughs around 2,300 BC. Farmers grew wheat, barley, vegetables such as lentils and onions, and fruits including dates, grapes, and figs. [[Ancient Egyptian agriculture]] relied on the [[Nile River]] and its seasonal flooding. Farming started in the predynastic period at the end of the [[Paleolithic]], after 10,000 BC. Staple food crops were grains such as wheat and barley, alongside industrial crops such as [[flax]] and [[papyrus]]. In [[Agriculture in India|India]], wheat, barley and [[jujube]] were domesticated by 9,000 BC, soon followed by sheep and goats. Cattle, sheep and goats were domesticated in [[Mehrgarh]] culture by 8,000–6,000 BC. Cotton was cultivated by the 5th–4th millennium BC. Archeological evidence indicates an animal-drawn [[plough]] from 2,500 BC in the [[Indus Valley Civilisation]]. In [[Agriculture in China|China]], from the 5th century BC there was a nationwide [[granary]] system and widespread [[sericulture|silk farming]]. Water-powered grain mills were in use by the 1st century BC, followed by irrigation. By the late 2nd century, [[heavy plough]] had been developed with iron ploughshares and [[mouldboard]]. These spread westwards across Eurasia. Asian rice was domesticated 8,200–13,500 years ago – depending on the [[molecular clock]] estimate that is used – on the Pearl River in southern China with a single genetic origin from the wild rice ''[[Oryza rufipogon]]''. In [[Agriculture in ancient Greece|Greece]] and [[Roman agriculture|Rome]], the major cereals were wheat, emmer, and barley, alongside vegetables including peas, beans, and olives. Sheep and goats were kept mainly for dairy products. In the Americas, crops domesticated in Mesoamerica (apart from [[teosinte]]) include squash, beans, and [[Theobroma cacao|cacao]]. Cocoa was being domesticated by the Mayo Chinchipe of the upper Amazon around 3,000 BC. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"History",
"Civilizations"
] | The [[domestic turkey|turkey]] was probably domesticated in Mexico or the American Southwest. The [[Aztec]] developed irrigation systems, formed [[Terrace (agriculture)|terraced]] hillsides, fertilized their soil, and developed [[chinampa]] or artificial islands. The [[Maya civilization|Mayas]] used extensive canal and raised field systems to farm swampland from 400 BC. [[Coca]] was domesticated in the Andes, as were the peanut, tomato, tobacco, and [[pineapple]]. Cotton was domesticated in [[Peru]] by 3,600 BC. Animals including [[llama]], [[alpaca]], and [[guinea pig]] were domesticated there. In [[History of agriculture in the United States|North America]], the indigenous people of the [[Eastern Agricultural Complex|East domesticated crops]] such as [[sunflower]], tobacco, squash and ''[[Chenopodium]]''. Wild foods including [[wild rice]] and [[maple sugar]] were harvested. The domesticated [[strawberry]] is a hybrid of a Chilean and a North American species, developed by breeding in Europe and North America. The [[Agriculture in the prehistoric Southwest|indigenous people of the Southwest]] and the [[Pacific Northwest]] practiced [[forest gardening]] and [[fire-stick farming]]. The [[Native American use of fire|natives controlled fire]] on a regional scale to create a low-intensity [[fire ecology]] that [[Sustainable agriculture|sustained a low-density agriculture]] in loose rotation; a sort of "wild" [[permaculture]]. A system of [[companion planting]] called [[Three Sisters (agriculture)|the Three Sisters]] was developed in North America. The three crops were [[winter squash]], maize, and climbing beans. [[Indigenous Australians]], long supposed to have been nomadic [[hunter-gatherers]], practised systematic burning, possibly to enhance natural productivity in fire-stick farming. The [[Gunditjmara]] and other groups developed eel farming and fish trapping systems from some 5,000 years ago. There is evidence of 'intensification' across the whole continent over that period. In two regions of Australia, the central west coast and eastern central, early farmers cultivated yams, native millet, and bush onions, possibly in permanent settlements. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"History",
"Revolution"
] | In the Middle Ages, both [[Arab Agricultural Revolution|in the Islamic world]] and in Europe, agriculture transformed with improved techniques and the diffusion of crop plants, including the introduction of sugar, rice, cotton and fruit trees (such as the orange) to Europe by way of [[Al-Andalus]]. After 1492 the [[Columbian exchange]] brought New World crops such as maize, potatoes, tomatoes, [[sweet potato]] and [[manioc]] to Europe, and Old World crops such as wheat, barley, rice and [[turnip]], and livestock (including horses, cattle, sheep and goats) to the Americas. [[Irrigation]], [[crop rotation]], and [[fertilizers]] advanced from the 17th century with the [[British Agricultural Revolution]], allowing global population to rise significantly. Since 1900 agriculture in developed nations, and to a lesser extent in the developing world, has seen large rises in productivity as [[Mechanized farming|mechanization]] replaces human labor, and assisted by [[synthetic fertilizer]], pesticides, and [[selective breeding]]. The [[Haber-Bosch]] method allowed the synthesis of [[ammonium nitrate]] fertilizer on an industrial scale, greatly increasing [[crop yields]] and sustaining a further increase in global population. Modern agriculture has raised or encountered ecological, political, and economic issues including [[water pollution]], [[biofuel]], [[genetically modified organism]], [[tariff]] and [[Agricultural subsidy|farm subsidies]], leading to alternative approaches such as the [[organic movement]]. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Types"
] | [[Pastoralism]] involves managing domesticated animals. In [[nomadic pastoralism]], herds of livestock are moved from place to place in search of pasture, fodder, and water. This type of farming is practised in arid and semi-arid regions of [[Sahara]], Central Asia and some parts of India. In [[shifting cultivation]], a small area of forest is cleared by cutting and burning the trees. The cleared land is used for growing crops for a few years until the soil becomes too infertile, and the area is abandoned. Another patch of land is selected and the process is repeated. This type of farming is practiced mainly in areas with abundant rainfall where the forest regenerates quickly. This practice is used in Northeast India, Southeast Asia, and the Amazon Basin. [[Subsistence farming]] is practiced to satisfy family or local needs alone, with little left over for transport elsewhere. It is intensively practiced in Monsoon Asia and South-East Asia. An estimated 2.5 billion subsistence farmers worked in 2018, cultivating about 60% of the earth's [[arable land]]. [[Intensive farming]] is cultivation to maximise productivity, with a low fallow ratio and a high use of inputs (water, fertilizer, pesticide and automation). It is practiced mainly in developed countries. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Contemporary agriculture",
"Status"
] | From the twentieth century, intensive agriculture increased productivity. It substituted synthetic fertilizers and pesticides for labor, but caused increased water pollution, and often involved farm subsidies. In recent years there has been a backlash against the [[environmental awareness|environmental effects]] of conventional agriculture, resulting in the [[organic farming|organic]], [[Regenerative agriculture|regenerative]], and [[sustainable agriculture]] movements. One of the major forces behind this movement has been the [[European Union]], which first certified [[organic food]] in 1991 and began reform of its [[Common Agricultural Policy]] (CAP) in 2005 to phase out commodity-linked farm subsidies, also known as [[Decoupling and re-coupling|decoupling]]. The growth of organic farming has renewed research in alternative technologies such as [[integrated pest management]], selective breeding, and [[controlled-environment agriculture]]. Recent mainstream technological developments include [[genetically modified food]]. Demand for non-food biofuel crops, development of former farm lands, rising transportation costs, [[Climate change and agriculture|climate change]], growing consumer demand in China and India, and [[population growth]], are threatening [[food security]] in many parts of the world. The [[International Fund for Agricultural Development]] posits that an increase in [[smallholding|smallholder agriculture]] may be part of the solution to concerns about [[food prices]] and overall food security, given the favorable experience of Vietnam. [[soil retrogression and degradation|Soil degradation]] and diseases such as [[stem rust]] are major concerns globally; approximately 40% of the world's agricultural land is seriously degraded. By 2015, the [[Agriculture in China|agricultural output of China]] was the largest in the world, followed by the European Union, India and the United States. Economists measure the [[total factor productivity]] of agriculture and by this measure agriculture in the United States is roughly 1.7 times more productive than it was in 1948. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Contemporary agriculture",
"Workforce"
] | Following the [[three-sector theory]], the number of people employed in agriculture and other [[primary sector|primary]] activities (such as fishing) can be more than 80% in the least developed countries, and less than 2% in the most highly developed countries. Since the [[Industrial Revolution]], many countries have made the transition to developed economies, and the proportion of people working in agriculture has steadily fallen. During the 16th century in Europe, for example, between 55 and 75% of the population was engaged in agriculture; by the 19th century, this had dropped to between 35 and 65%. In the same countries today, the figure is less than 10%. At the start of the 21st century, some one billion people, or over 1/3 of the available work force, were employed in agriculture. It constitutes approximately 70% of the global employment of children, and in many countries employs the largest percentage of women of any industry. The service sector overtook the agricultural sector as the largest global employer in 2007. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Contemporary agriculture",
"Safety"
] | Agriculture, specifically farming, remains a hazardous industry, and farmers worldwide remain at high risk of work-related injuries, lung disease, [[noise-induced hearing loss]], skin diseases, as well as certain cancers related to chemical use and prolonged sun exposure. On [[industrial agriculture|industrialized farms]], injuries frequently involve the use of [[agricultural machinery]], and a common cause of fatal agricultural injuries in developed countries is [[Rollover protection structure|tractor rollovers]]. Pesticides and other chemicals used in farming can be [[Health effects of pesticides|hazardous to worker health]], and workers exposed to pesticides may experience illness or have children with birth defects. As an industry in which families commonly share in work and live on the farm itself, entire families can be at risk for injuries, illness, and death. Ages 0–6 May be an especially vulnerable population in agriculture; common causes of fatal injuries among young farm workers include drowning, machinery and motor accidents, including with all-terrain vehicles. The [[International Labour Organization]] considers agriculture "one of the most hazardous of all economic sectors". It estimates that the annual work-related death toll among agricultural employees is at least 170,000, twice the average rate of other jobs. In addition, incidences of death, injury and illness related to agricultural activities often go unreported. The organization has developed the [[Safety and Health in Agriculture Convention, 2001]], which covers the range of risks in the agriculture occupation, the prevention of these risks and the role that individuals and organizations engaged in agriculture should play. In the United States, agriculture has been identified by the [[National Institute for Occupational Safety and Health]] as a priority industry sector in the [[National Occupational Research Agenda]] to identify and provide intervention strategies for occupational health and safety issues. In the European Union, the [[European Agency for Safety and Health at Work]] has issued guidelines on implementing health and safety directives in agriculture, livestock farming, horticulture, and forestry. The Agricultural Safety and Health Council of America (ASHCA) also holds a yearly summit to discuss safety. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Production",
"Crop cultivation systems"
] | Cropping systems vary among farms depending on the available resources and constraints; geography and climate of the farm; government policy; economic, social and political pressures; and the philosophy and culture of the farmer. Shifting cultivation (or [[slash and burn]]) is a system in which forests are burnt, releasing nutrients to support cultivation of annual and then [[perennial plant|perennial]] crops for a period of several years. Then the plot is left fallow to regrow forest, and the farmer moves to a new plot, returning after many more years (10–20). This fallow period is shortened if population density grows, requiring the input of nutrients (fertilizer or [[manure]]) and some manual [[pest control]]. Annual cultivation is the next phase of intensity in which there is no fallow period. This requires even greater nutrient and pest control inputs. Further industrialization led to the use of [[monoculture]], when one [[cultivar]] is planted on a large acreage. Because of the low [[biodiversity]], nutrient use is uniform and pests tend to build up, necessitating the greater use of [[pesticide]] and fertilizers. [[Multiple cropping]], in which several crops are grown sequentially in one year, and [[intercropping]], when several crops are grown at the same time, are other kinds of annual cropping systems known as [[polyculture]]. In [[subtropics|subtropical]] and [[arid]] environments, the timing and extent of agriculture may be limited by rainfall, either not allowing multiple annual crops in a year, or requiring irrigation. In all of these environments perennial crops are grown (coffee, chocolate) and systems are practiced such as agroforestry. In [[Temperateness|temperate]] environments, where ecosystems were predominantly [[grassland]] or [[prairie]], highly productive annual farming is the dominant agricultural system. Important categories of food crops include cereals, legumes, forage, fruits and vegetables. [[Natural fiber]] include cotton, [[wool]], [[hemp]], silk and [[flax]]. Specific crops are cultivated in distinct [[growing region]] throughout the world. Production is listed in millions of metric tons, based on [[Food and Agriculture Organization|FAO]] estimates. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Production",
"Livestock production systems"
] | Animal husbandry is the breeding and raising of animals for meat, milk, [[egg (food)|eggs]], or [[wool]], and for work and transport. [[Working animal]], including horses, [[mule]], [[ox]], [[water buffalo]], camels, llamas, alpacas, donkeys, and dogs, have for centuries been used to help cultivate fields, [[harvest]] crops, wrangle other animals, and transport farm products to buyers. Livestock production systems can be defined based on feed source, as grassland-based, mixed, and landless. , 30% of Earth's ice- and water-free area was used for producing livestock, with the sector employing approximately 1.3 billion people. Between the 1960s and the 2000s, there was a significant increase in livestock production, both by numbers and by carcass weight, especially among beef, pigs and chickens, the latter of which had production increased by almost a factor of 10. Non-meat animals, such as milk cows and egg-producing chickens, also showed significant production increases. Global cattle, sheep and goat populations are expected to continue to increase sharply through 2050. [[Aquaculture]] or fish farming, the production of fish for human consumption in confined operations, is one of the fastest growing sectors of food production, growing at an average of 9% a year between 1975 and 2007. During the second half of the 20th century, producers using selective breeding focused on creating livestock [[breed]] and [[crossbreed]] that increased production, while mostly disregarding the need to preserve [[genetic diversity]]. This trend has led to a significant decrease in genetic diversity and resources among livestock breeds, leading to a corresponding decrease in disease resistance and local adaptations previously found among traditional breeds. Grassland based livestock production relies upon plant material such as [[shrubland]], [[rangeland]], and [[managed intensive rotational grazing|pastures]] for feeding [[ruminant]] animals. Outside nutrient inputs may be used, however manure is returned directly to the grassland as a major nutrient source. This system is particularly important in areas where crop production is not feasible because of climate or soil, representing 30–40 million pastoralists. Mixed production systems use grassland, [[fodder]] crops and grain feed crops as feed for ruminant and monogastric (one stomach; mainly chickens and pigs) livestock. Manure is typically recycled in mixed systems as a fertilizer for crops. Landless systems rely upon feed from outside the farm, representing the de-linking of crop and livestock production found more prevalently in [[Organisation for Economic Co-operation and Development]] member countries. Synthetic fertilizers are more heavily relied upon for crop production and manure use becomes a challenge as well as a source for pollution. Industrialized countries use these operations to produce much of the global supplies of poultry and pork. Scientists estimate that 75% of the growth in livestock production between 2003 and 2030 will be in [[confined animal feeding operations]], sometimes called [[factory farming]]. Much of this growth is happening in developing countries in Asia, with much smaller amounts of growth in Africa. Some of the practices used in commercial livestock production, including the usage of [[growth hormone]], are controversial. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Production",
"Production practices"
] | Tillage is the practice of breaking up the soil with tools such as the plow or [[harrow (tool)|harrow]] to prepare for planting, for nutrient incorporation, or for pest control. Tillage varies in intensity from conventional to [[no-till farming|no-till]]. It may improve productivity by warming the soil, incorporating fertilizer and controlling weeds, but also renders soil more prone to erosion, triggers the decomposition of organic matter releasing CO, and reduces the abundance and diversity of soil organisms. Pest control includes the management of weeds, insects, [[mite]], and diseases. Chemical (pesticides), biological ([[biocontrol]]), mechanical (tillage), and cultural practices are used. Cultural practices include crop rotation, [[culling]], [[cover crop]], intercropping, [[compost]], avoidance, and [[Disease resistance in fruit and vegetables|resistance]]. Integrated pest management attempts to use all of these methods to keep pest populations below the number which would cause economic loss, and recommends pesticides as a last resort. [[Nutrient management]] includes both the source of nutrient inputs for crop and livestock production, and the method of use of manure produced by livestock. Nutrient inputs can be chemical inorganic fertilizers, manure, [[green manure]], compost and minerals. Crop nutrient use may also be managed using cultural techniques such as crop rotation or a [[fallow]] period. Manure is used either by holding livestock where the feed crop is growing, such as in managed intensive rotational grazing, or [[Manure spreader|by spreading]] either dry or liquid formulations of manure on cropland or [[pasture]]. [[Water management]] is needed where rainfall is insufficient or variable, which occurs to some degree in most regions of the world. Some farmers use irrigation to supplement rainfall. In other areas such as the [[Great Plains]] in the U.S. and Canada, farmers use a fallow year to conserve soil moisture to use for growing a crop in the following year. Agriculture represents 70% of freshwater use worldwide. Production practices are an important cause of on-farm losses, these include inadequate harvesting time, climatic conditions, practices applied at harvest and handling, and challenges in marketing produce. Significant losses are caused by inadequate storage conditions as well as decisions made at earlier stages of the supply chain, which predispose products to a shorter shelf life. According to a report by the [[International Food Policy Research Institute]], agricultural technologies will have the greatest impact on food production if adopted in combination with each other; using a model that assessed how eleven technologies could impact agricultural productivity, food security and trade by 2050, the International Food Policy Research Institute found that the number of people at risk from hunger could be reduced by as much as 40% and food prices could be reduced by almost half. [[Payment for ecosystem services]] is a method of providing additional incentives to encourage farmers to conserve some aspects of the environment. Measures might include paying for reforestation upstream of a city, to improve the supply of fresh water. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Crop alteration and biotechnology",
"Plant breeding"
] | Crop alteration has been practiced by humankind for thousands of years, since the beginning of civilization. Altering crops through breeding practices changes the genetic make-up of a plant to develop crops with more beneficial characteristics for humans, for example, larger fruits or seeds, drought-tolerance, or resistance to pests. Significant advances in plant breeding ensued after the work of geneticist [[Gregor Mendel]]. His work on [[dominant allele|dominant]] and [[recessive allele]], although initially largely ignored for almost 50 years, gave plant breeders a better understanding of genetics and breeding techniques. Crop breeding includes techniques such as plant selection with desirable traits, [[self-pollination]] and [[cross-pollination]], and molecular techniques that genetically modify the organism. Domestication of plants has, over the centuries increased yield, improved disease resistance and [[drought tolerance]], eased harvest and improved the taste and nutritional value of crop plants. Careful selection and breeding have had enormous effects on the characteristics of crop plants. Plant selection and breeding in the 1920s and 1930s improved pasture (grasses and clover) in New Zealand. Extensive X-ray and ultraviolet induced mutagenesis efforts (i.e. primitive genetic engineering) during the 1950s produced the modern commercial varieties of grains such as wheat, corn (maize) and barley. The [[Green Revolution]] popularized the use of conventional [[Hybrid (biology)|hybridization]] to sharply increase yield by creating "high-yielding varieties". For example, average yields of corn (maize) in the US have increased from around 2.5 tons per hectare (t/ha) (40 bushels per acre) in 1900 to about 9.4 t/ha (150 bushels per acre) in 2001. Similarly, worldwide average wheat yields have increased from less than 1 t/ha in 1900 to more than 2.5 t/ha in 1990. South American average wheat yields are around 2 t/ha, African under 1 t/ha, and Egypt and Arabia up to 3.5 to 4 t/ha with irrigation. In contrast, the average wheat yield in countries such as France is over 8 t/ha. Variations in yields are due mainly to variation in climate, genetics, and the level of intensive farming techniques (use of fertilizers, chemical pest control, growth control to avoid lodging). | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Crop alteration and biotechnology",
"Genetic engineering"
] | Genetically modified organisms (GMO) are [[organism]] whose [[Genetics|genetic]] material has been altered by genetic engineering techniques generally known as [[recombinant DNA technology]]. Genetic engineering has expanded the genes available to breeders to use in creating desired germlines for new crops. Increased durability, nutritional content, insect and virus resistance and herbicide tolerance are a few of the attributes bred into crops through genetic engineering. For some, GMO crops cause [[food safety]] and [[food labeling regulations|food labeling]] concerns. Numerous countries have placed restrictions on the production, import or use of GMO foods and crops. Currently a global treaty, the [[Biosafety Protocol]], regulates the trade of GMOs. There is ongoing discussion regarding the labeling of foods made from GMOs, and while the EU currently requires all GMO foods to be labeled, the US does not. Herbicide-resistant seed has a gene implanted into its genome that allows the plants to tolerate exposure to herbicides, including [[glyphosate]]. These seeds allow the farmer to grow a crop that can be sprayed with herbicides to control weeds without harming the resistant crop. Herbicide-tolerant crops are used by farmers worldwide. With the increasing use of herbicide-tolerant crops, comes an increase in the use of glyphosate-based herbicide sprays. In some areas glyphosate resistant weeds have developed, causing farmers to switch to other herbicides. Some studies also link widespread glyphosate usage to iron deficiencies in some crops, which is both a crop production and a nutritional quality concern, with potential economic and health implications. Other GMO crops used by growers include insect-resistant crops, which have a gene from the soil bacterium ''[[Bacillus thuringiensis]]'' (Bt), which produces a toxin specific to insects. These crops resist damage by insects. Some believe that similar or better pest-resistance traits can be acquired through traditional breeding practices, and resistance to various pests can be gained through hybridization or cross-pollination with wild species. In some cases, wild species are the primary source of resistance traits; some tomato cultivars that have gained resistance to at least 19 diseases did so through crossing with wild populations of tomatoes. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Environmental impact",
"Effects and costs"
] | Agriculture imposes multiple external costs upon society through effects such as pesticide damage to nature (especially herbicides and insecticides), nutrient runoff, excessive water usage, and loss of natural environment. A 2000 assessment of agriculture in the UK determined total external costs for 1996 of £2,343 million, or £208 per hectare. A 2005 analysis of these costs in the US concluded that cropland imposes approximately $5 to $16 billion ($30 to $96 per hectare), while livestock production imposes $714 million. Both studies, which focused solely on the fiscal impacts, concluded that more should be done to internalize external costs. Neither included subsidies in their analysis, but they noted that subsidies also influence the cost of agriculture to society. Agriculture seeks to increase yield and to reduce costs. Yield increases with inputs such as fertilisers and removal of pathogens, predators, and competitors (such as weeds). Costs decrease with increasing scale of farm units, such as making fields larger; this means removing [[hedge]], ditches and other areas of habitat. Pesticides kill insects, plants and fungi. These and other measures have cut biodiversity to very low levels on intensively farmed land. In 2010, the [[International Resource Panel]] of the [[United Nations Environment Programme]] assessed the environmental impacts of consumption and production. It found that agriculture and food consumption are two of the most important drivers of environmental pressures, particularly habitat change, climate change, water use and toxic emissions. Agriculture is the main source of toxins released into the environment, including insecticides, especially those used on cotton. The 2011 UNEP Green Economy report states that "[a]agricultural operations, excluding land use changes, produce approximately 13 per cent of anthropogenic global GHG emissions. This includes GHGs emitted by the use of inorganic fertilizers agro-chemical pesticides and herbicides; (GHG emissions resulting from production of these inputs are included in industrial emissions); and fossil fuel-energy inputs. "On average we find that the total amount of fresh residues from agricultural and forestry production for second- generation biofuel production amounts to 3.8 billion tonnes per year between 2011 and 2050 (with an average annual growth rate of 11 per cent throughout the period analysed, accounting for higher growth during early years, 48 per cent for 2011–2020 and an average 2 per cent annual expansion after 2020)." According to FAO’s The State of Food and Agriculture 2019, food production, and in particular food loss and waste, may generate significant negative environmental impacts. It is forecast that a growing population and rising incomes will lead to an increase in demand for agricultural products, exerting even more pressure on the world’s natural resources. This emphasizes the urgency of reducing food loss and waste since it will always improve resource use efficiency and lower GHG emissions per unit of food consumed because more food reaches the consumer for a given level of resources used. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Environmental impact",
"Livestock issues"
] | A senior UN official, Henning Steinfeld, said that "Livestock are one of the most significant contributors to today's most serious environmental problems". Livestock production occupies 70% of all land used for agriculture, or 30% of the land surface of the planet. It is one of the largest sources of [[greenhouse gas]], responsible for 18% of the world's [[greenhouse gas emissions]] as measured in CO equivalents. By comparison, all transportation emits 13.5% of the CO. It produces 65% of human-related [[nitrous oxide]] (which has 296 times the global warming potential of CO) and 37% of all human-induced [[methane]] (which is 23 times as warming as CO.) It also generates 64% of the [[ammonia]] emission. Livestock expansion is cited as a key factor driving [[deforestation]]; in the Amazon basin 70% of [[Deforestation of the Amazon Rainforest|previously forested area]] is now occupied by pastures and the remainder used for feedcrops. Through deforestation and [[land degradation]], livestock is also driving reductions in biodiversity. Furthermore, the UNEP states that "[[methane emissions]] from global livestock are projected to increase by 60 per cent by 2030 under current practices and consumption patterns." | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Environmental impact",
"Land and water issues"
] | Land transformation, the use of land to yield goods and services, is the most substantial way humans alter the Earth's ecosystems, and is considered the driving force in the [[Biodiversity loss|loss of biodiversity]]. Estimates of the amount of land transformed by humans vary from 39 to 50%. Land degradation, the long-term decline in ecosystem function and productivity, is estimated to be occurring on 24% of land worldwide, with cropland overrepresented. The UN-FAO report cites land management as the driving factor behind degradation and reports that 1.5 billion people rely upon the degrading land. Degradation can be deforestation, [[desertification]], [[soil erosion]], mineral depletion, or chemical degradation ([[soil acidification|acidification]] and [[Soil salinity|salinization]]). Agriculture lead to rise in [[Zoonotic disease]] like the [[Coronavirus disease 2019]], by degrading natural buffers between humans and animals, reducing biodiversity and creating big groups of genetically similar animals. [[Eutrophication]], excessive nutrients in [[aquatic ecosystem]] resulting in [[algal bloom]] and [[anoxic waters|anoxia]], leads to [[fish kill]], loss of biodiversity, and renders water unfit for drinking and other industrial uses. Excessive fertilization and manure application to cropland, as well as high livestock stocking densities cause nutrient (mainly [[nitrogen]] and [[phosphorus]]) [[surface runoff|runoff]] and [[leaching (agriculture)|leaching]] from agricultural land. These nutrients are major [[nonpoint source pollution|nonpoint pollutants]] contributing to [[eutrophication]] of aquatic ecosystems and pollution of groundwater, with harmful effects on human populations. Fertilisers also reduce terrestrial biodiversity by increasing competition for light, favouring those species that are able to benefit from the added nutrients. Agriculture accounts for 70 percent of withdrawals of freshwater resources. Agriculture is a major draw on water from [[aquifer]], and currently draws from those underground water sources at an unsustainable rate. It is long known that aquifers in areas as diverse as northern China, the [[Ganges|Upper Ganges]] and the western US are being depleted, and new research extends these problems to aquifers in Iran, Mexico and Saudi Arabia. Increasing pressure is being placed on water resources by industry and urban areas, meaning that [[water scarcity]] is increasing and agriculture is facing the challenge of producing more food for the world's growing population with reduced water resources. [[Farm water|Agricultural water]] usage can also cause major environmental problems, including the destruction of natural wetlands, the spread of water-borne diseases, and land degradation through salinization and waterlogging, when irrigation is performed incorrectly. | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
[
"Environmental impact",
"Pesticides"
] | Pesticide use has increased since 1950 to 2.5million short tons annually worldwide, yet crop loss from pests has remained relatively constant. The World Health Organization estimated in 1992 that three million pesticide poisonings occur annually, causing 220,000 deaths. Pesticides select for [[pesticide resistance]] in the pest population, leading to a condition termed the "pesticide treadmill" in which pest resistance warrants the development of a new pesticide. An alternative argument is that the way to "save the environment" and prevent famine is by using pesticides and intensive high yield farming, a view exemplified by a quote heading the Center for Global Food Issues website: 'Growing more per acre leaves more land for nature'. However, critics argue that a trade-off between the environment and a need for food is not inevitable, and that pesticides simply replace [[good agricultural practices|good agronomic practices]] such as crop rotation. The [[Push–pull agricultural pest management]] technique involves intercropping, using plant aromas to repel pests from crops (push) and to lure them to a place from which they can then be removed (pull). | 627 | Agriculture | [
"Agriculture",
"Agronomy",
"Food industry"
] | [
"Ecoagriculture",
"Agroecology",
"Remote sensing",
"List of documentary films about agriculture",
"Agricultural robot",
"Building-integrated agriculture",
"Corporate farming",
"Vertical farming",
"Vegetable farming",
"Agricultural engineering",
"Pharming (genetics)",
"Hill farming",
"Contract farming",
"Agricultural aircraft",
"Crofting",
"Subsistence economy",
"Aeroponics"
] |
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