Passerine
A passerine is any bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or – less – as songbirds, passerines are distinguished from other orders of birds by the arrangement of their toes, which facilitates perching. With more than 110 families and some 6,409 identified species, Passeriformes is the largest order of birds and among the most diverse orders of terrestrial vertebrates. Passerines are divided into three clades, Acanthisitti and Passeri; the passerines contain several groups of brood parasites such as the viduas, cuckoo-finches, the cowbirds. Most passerines are omnivorous; the terms "passerine" and "Passeriformes" are derived from the scientific name of the house sparrow, Passer domesticus, from the Latin term passer, which refers to sparrows and similar small birds. The order is divided into three suborders, Tyranni and the basal Acanthisitti. Oscines have the best control of their syrinx muscles among birds, producing a wide range of songs and other vocalizations.
The acanthisittids or New Zealand wrens are tiny birds restricted to New Zealand, at least in modern times. Most passerines are smaller than typical members of other avian orders; the heaviest and altogether largest passerines are the thick-billed raven and the larger races of common raven, each exceeding 1.5 kg and 70 cm. The superb lyrebird and some birds-of-paradise, due to long tails or tail coverts, are longer overall; the smallest passerine is the short-tailed pygmy tyrant, at 4.2 g. The foot of a passerine has three toes directed forward and one toe directed backward, called anisodactyl arrangement; this arrangement enables the passerine birds to perch upon vertical surfaces, such as trees and cliffs. The toes have no webbing or joining, but in some cotingas, the second and third toes are united at their basal third; the hind toe joins the leg at the same level as the front toes. The passeriformes have this toe arrangement in common with hunting birds like falcons; the leg arrangement of passerine birds contains a special adaptation for perching.
A tendon in the rear of the leg running from the underside of the toes to the muscle behind the tibiotarsus will automatically be pulled and tighten when the leg bends, causing the foot to curl and become stiff when the bird lands on a branch. This enables passerines to sleep. Most passerine birds develop 12 tail feathers, although the superb lyrebird has 16. Certain species of passerines have stiff tail feathers, which help the birds balance themselves when perching upon vertical surfaces; some passerines in the family Ploceidae, are well known for their elaborate sexual ornaments, including long tails. A well-known example is the long-tailed widowbird; the chicks of passerines are altricial: blind and helpless when hatched from their eggs. Hence, the chicks require extensive parental care. Most passerines lay coloured eggs, in contrast with nonpasserines, most of whose eggs are white except in some ground-nesting groups such as Charadriiformes and nightjars, where camouflage is necessary, in some parasitic cuckoos, which match the passerine host's egg.
Vinous-throated parrotbill has two egg colours and blue. This can prevent the brood parasitic Common cuckoo. Clutches vary in size: some larger passerines of Australia such as lyrebirds and scrub-robins lay only a single egg, most smaller passerines in warmer climates lay between two and five, while in the higher latitudes of the Northern Hemisphere, hole-nesting species like tits can lay up to a dozen and other species around five or six; the family Viduidae do not build their own nests, they lay eggs in other birds' nests. The evolutionary history of the passerine families and the relationships among them remained rather mysterious until the late 20th century. In many cases, passerine families were grouped together on the basis of morphological similarities that, it is now believed, are the result of convergent evolution, not a close genetic relationship. For example, the wrens of the Eurasia. Much research remains to be done, but advances in molecular biology and improved paleobiogeographical data are revealing a clearer picture of passerine origins and evolution that reconciles molecular affinities, the constraints of morphology and the specifics of the fossil record.
The first passerines are now thought to have evolved in the Southern Hemisphere in the late Paleocene or early Eocene, around 50 million years ago. The initial split was between the New Zealand wrens and all other passerines, the second split involved the Tyranni and the Passeri; the latter experienced a great radiation of forms out of the Australian continent. A major branch of the Passeri, parvorder Passerida, expanded deep into Eurasia and Africa, where a further explosive radiation of new lineages occurred; this led to three major Passerida lineages comprising about 4,000 species, which in addition to the Corvida and numerous minor linea
Eastern newt
The eastern newt is a common newt of eastern North America. It frequents small lakes and streams or near-by wet forests; the eastern newt produces tetrodotoxin which makes the species unpalatable to predatory fish and crayfish. It has a lifespan of 12 to 15 years in the wild, may grow to five inches in length; these animals are common aquarium pets, being sold commercially. The striking bright orange juvenile stage, land-dwelling, is known as a red eft; some sources blend the general name of the species and that of the red-spotted newt subspecies into the eastern red-spotted newt. The eastern newt includes these four subspecies: Red-spotted newt Broken-striped newt Central newt Peninsula newt The central newt is a subspecies of the eastern newt. From 2.5 inches to 4 inches in length. Central newts are brown or green with fine black dots all over the body. There may be a row of red spots on each side of the body; the belly is yellow or orange, is noticeably lighter than the rest of the body. The skin of newts is not as slippery as the skin of salamanders, may appear to be rough and dry for parts of their lives.
Eastern newts have three stages of life: the aquatic larva or tadpole, the red eft or terrestrial juvenile stage, the aquatic adult. The larva does not leave the pond environment where it was hatched. Larvae are brown-green in color, shed their gills when they transform into the red eft; the red eft stage is a bright orangish-red in color, with darker red spots outlined in black. An eastern newt can have as many as 21 of these spots; the pattern of these spots differs among the subspecies. An eastern newt's time to get from larva to eft is unknown. During this stage, the eft may travel far, acting as a dispersal stage from one pond to another, ensuring outcrossing in the population; the striking coloration of this stage is an example of aposematism — or "warning coloration" —, a type of antipredator adaptation in which a "warning signal" is associated with the unprofitability of a prey item to potential predators. After two or three years, the eft transforms into the aquatic adult; the adult's skin is a dull olive green dorsally, with a dull yellow belly, but retains the eft's characteristic black-rimmed red spots.
It develops characteristically slimy skin. It is common for the peninsula newt to be neotenic, with a larva transforming directly into a sexually mature aquatic adult, never losing its external gills; the red eft stage is. Eastern newts home using magnetic orientation, their magnetoreception system seems to be a hybrid of polarity-based inclination and a sun-dependent compass. Shoreward-bound eastern newts will orient themselves quite differently under light with wavelengths around 400 nm than light with wavelengths around 600 nm, while homing newts will orient themselves the same way under both short and long wavelengths. Ferromagnetic material biogenic magnetite, is present in the eastern newt's body. Eastern newts are at home in both deciduous forests, they need a moist environment with either a temporary or permanent body of water, thrive best in a muddy environment. During the eft stage, they may travel far from their original location. Red efts may be seen in a forest after a rainstorm. Adults will move to land during a dry spell.
Eastern newts have some amount of toxins in their skin, brightly colored to act as a warning. Only 2% of larvae make it to the eft stage; some larvae have been found in the pitchers of the carnivorous plant Sarracenia purpurea. Eastern newts eat a variety of prey, such as insects, small mollusks and crustaceans, young amphibians and frog eggs. Although eastern newts are widespread throughout North America, like many other species of amphibians are threatened by several factors including, habitat fragmentation, climate change, invasive species, over-exploitation, emergent infectious diseases. Wild eastern newts are known hosts of Batrachochytrium Ranavirus, they are highly susceptible to the newly emergent chytrid fungus Batrachochytrium salamandrivorans. Grayson, Kristine L. Frontiers in Zoology. 9: 24. Doi:10.1186/1742-9994-9-24. PMC 3478290. PMID 22988835. Brossman, Kelly H. "Eastern Newt larvae alter morphological but not chemical defenses in response to predator cues". Canadian Journal of Zoology.
92: 279–83. Doi:10.1139/cjz-2013-0244. Notophthalmus viridescens. Animal Diversity Web. Eastern Newt (Notophthalmus viridescens. Checklist of Amphibian Species and Identification Guide. USGS Northern Prairie Wildlife Research Center. Red-spotted Newt. Virginia Department of Game and Inland Fisheries. Eastern Newt Caresheet and Photos. Caudata Culture. Notophthalmus viridescens Species Account. AmphibiaWeb. Central Newt on Reptiles and Amphibians of Iowa
California
California is a state in the Pacific Region of the United States. With 39.6 million residents, California is the most populous U. S. the third-largest by area. The state capital is Sacramento; the Greater Los Angeles Area and the San Francisco Bay Area are the nation's second and fifth most populous urban regions, with 18.7 million and 9.7 million residents respectively. Los Angeles is California's most populous city, the country's second most populous, after New York City. California has the nation's most populous county, Los Angeles County, its largest county by area, San Bernardino County; the City and County of San Francisco is both the country's second-most densely populated major city after New York City and the fifth-most densely populated county, behind only four of the five New York City boroughs. California's $3.0 trillion economy is larger than that of any other state, larger than those of Texas and Florida combined, the largest sub-national economy in the world. If it were a country, California would be the 5th largest economy in the world, the 36th most populous as of 2017.
The Greater Los Angeles Area and the San Francisco Bay Area are the nation's second- and third-largest urban economies, after the New York metropolitan area. The San Francisco Bay Area PSA had the nation's highest GDP per capita in 2017 among large PSAs, is home to three of the world's ten largest companies by market capitalization and four of the world's ten richest people. California is considered a global trendsetter in popular culture, innovation and politics, it is considered the origin of the American film industry, the hippie counterculture, fast food, the Internet, the personal computer, among others. The San Francisco Bay Area and the Greater Los Angeles Area are seen as global centers of the technology and entertainment industries, respectively. California has a diverse economy: 58% of the state's economy is centered on finance, real estate services and professional, scientific and technical business services. Although it accounts for only 1.5% of the state's economy, California's agriculture industry has the highest output of any U.
S. state. California is bordered by Oregon to the north and Arizona to the east, the Mexican state of Baja California to the south; the state's diverse geography ranges from the Pacific Coast in the west to the Sierra Nevada mountain range in the east, from the redwood–Douglas fir forests in the northwest to the Mojave Desert in the southeast. The Central Valley, a major agricultural area, dominates the state's center. Although California is well-known for its warm Mediterranean climate, the large size of the state results in climates that vary from moist temperate rainforest in the north to arid desert in the interior, as well as snowy alpine in the mountains. Over time and wildfires have become more pervasive features. What is now California was first settled by various Native Californian tribes before being explored by a number of European expeditions during the 16th and 17th centuries; the Spanish Empire claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its successful war for independence but was ceded to the United States in 1848 after the Mexican–American War.
The western portion of Alta California was organized and admitted as the 31st state on September 9, 1850. The California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom; the word California referred to the Baja California Peninsula of Mexico. The name derived from the mythical island California in the fictional story of Queen Calafia, as recorded in a 1510 work The Adventures of Esplandián by Garci Rodríguez de Montalvo; this work was the fifth in a popular Spanish chivalric romance series that began with Amadis de Gaula. Queen Calafia's kingdom was said to be a remote land rich in gold and pearls, inhabited by beautiful black women who wore gold armor and lived like Amazons, as well as griffins and other strange beasts. In the fictional paradise, the ruler Queen Calafia fought alongside Muslims and her name may have been chosen to echo the title of a Muslim leader, the Caliph. It's possible.
Know ye that at the right hand of the Indies there is an island called California close to that part of the Terrestrial Paradise, inhabited by black women without a single man among them, they lived in the manner of Amazons. They were robust of body with great virtue; the island itself is one of the wildest in the world on account of the craggy rocks. Shortened forms of the state's name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. Various estimates of the native population range from 100,000 to 300,000; the Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups were diverse in their political organization with bands, villages, on the resource-rich coasts, large chiefdoms, such as the Chumash and Salinan.
Trade, intermarriage a
Salamander
Salamanders are a group of amphibians characterized by a lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, the presence of a tail in both larvae and adults. All present-day salamander families are grouped together under the order Urodela. Salamander diversity is most abundant in the Northern Hemisphere and most species are found in the Holarctic ecozone, with some species present in the Neotropical zone. Salamanders have more than four toes on their front legs and five on their rear legs, but some species have fewer digits and others lack hind limbs, their permeable skin makes them reliant on habitats in or near water or other cool, damp places. Some salamander species are aquatic throughout their lives, some take to the water intermittently, others are terrestrial as adults, they are capable of regenerating lost limbs, as well as other damaged parts of their bodies. Researchers hope to reverse engineer the remarkable regenerative processes for potential human medical applications, such as brain and spinal cord injury treatment or preventing harmful scarring during heart surgery recovery.
Members of the family Salamandridae are known as newts and lack the costal grooves along the sides of their bodies typical of other groups. The skin of some species contains the powerful poison tetrodotoxin. Salamanders lay eggs in water and have aquatic larvae, but great variation occurs in their lifecycles; some species in harsh environments reproduce while still in the larval state. The skin lacks scales and is moist and smooth to the touch, except in newts of the Salamandridae, which may have velvety or warty skin, wet to the touch; the skin may be drab or brightly colored, exhibiting various patterns of stripes, spots, blotches, or dots. Male newts become colored during the breeding season. Cave species dwelling in darkness lack pigmentation and have a translucent pink or pearlescent appearance. Salamanders range in size from the minute salamanders, with a total length of 2.7 cm, including the tail, to the Chinese giant salamander which reaches 1.8 m and weighs up to 65 kg. Most, are between 10 and 20 cm in length.
An adult salamander resembles a small lizard, having a basal tetrapod body form with a cylindrical trunk, four limbs, a long tail. Except in the family Salamandridae, the head and tail have a number of vertical depressions in the surface which run from the mid-dorsal region to the ventral area and are known as costal grooves, their function seems to be to help keep the skin moist by channeling water over the surface of the body. Some aquatic species, such as sirens and amphiumas, have reduced or absent hind limbs, giving them an eel-like appearance, but in most species, the front and rear limbs are about the same length and project sidewards raising the trunk off the ground; the feet are broad with short digits four on the front feet and five on the rear. Salamanders do not have claws, the shape of the foot varies according to the animal's habitat. Climbing species have elongated, square-tipped toes, while rock-dwellers have larger feet with short, blunt toes; the tree-climbing salamander has plate-like webbed feet which adhere to smooth surfaces by suction, while the rock-climbing Hydromantes species from California have feet with fleshy webs and short digits and use their tails as an extra limb.
When ascending, the tail props up the rear of the body, while one hind foot moves forward and swings to the other side to provide support as the other hind foot advances. In larvae and aquatic salamanders, the tail is laterally flattened, has dorsal and ventral fins, undulates from side to side to propel the animal through the water. In the families Ambystomatidae and Salamandridae, the male's tail, larger than that of the female, is used during the amplexus embrace to propel the mating couple to a secluded location. In terrestrial species, the tail moves to counterbalance the animal as it runs, while in the arboreal salamander and other tree-climbing species, it is prehensile; the tail is used by certain plethodontid salamanders that can jump, to help launch themselves into the air. The tail is used as a storage organ for proteins and lipids, it functions as a defense against predation, when it may be lashed at the attacker or autotomised when grabbed. Unlike frogs, an adult salamander is able to regenerate its tail when these are lost.
The skin of salamanders, in common with other amphibians, is thin, permeable to water, serves as a respiratory membrane, is well-supplied with glands. It has cornified outer layers, renewed periodically through a skin shedding process controlled by hormones from the pituitary and thyroid glands. During moulting, the skin breaks around the mouth, the animal moves forwards through the gap to shed the skin; when the front limbs have been worked clear, a series of body ripples pushes the skin towards the rear. The hind limbs are extracted and push the skin farther back, before it is freed by friction as the salamander moves forward with the tail pressed against the ground; the animal then eats the resulting sloughed skin. Glands in the skin discharge mucus which keeps the skin moist, an important factor in skin respiration and thermoregulation; the sticky layer helps protect against bacterial infections and molds, reduces friction when swimming, makes the animal slippery and more difficult for predators to catch.
Granular glands scattered on the upper surface the head and tail, produce repel
Salmonella
Salmonella is a genus of rod-shaped Gram-negative bacteria of the family Enterobacteriaceae. The two species of Salmonella are Salmonella Salmonella bongori. S. enterica is the type species and is further divided into six subspecies that include over 2,600 serotypes. Salmonella species are non-spore-forming, predominantly motile enterobacteria with cell diameters between about 0.7 and 1.5 µm, lengths from 2 to 5 µm, peritrichous flagella. They are chemotrophs, obtaining their energy from oxidation and reduction reactions using organic sources, they are facultative aerobes, capable of generating ATP with oxygen when it is available, or when oxygen is not available, using other electron acceptors or fermentation. S. enterica subspecies are found worldwide in the environment. S. bongori is restricted to cold-blooded animals reptiles. Salmonella species are intracellular pathogens. Nontyphoidal serotypes can be transferred from human-to-human, they invade only the gastrointestinal tract and cause salmonellosis, the symptoms of which can be resolved without antibiotics.
However, in sub-Saharan Africa, nontyphoidal Salmonella can be invasive and cause paratyphoid fever, which requires immediate treatment with antibiotics. Typhoidal serotypes can only be transferred from human-to-human, can cause food-borne infection, typhoid fever, paratyphoid fever. Typhoid fever is caused by Salmonella invading the bloodstream, or in addition spreads throughout the body, invades organs, secretes endotoxins; this can lead to life-threatening hypovolemic shock and septic shock, requires intensive care including antibiotics. The collapse of the Aztec society in Mesoamerica is linked to a catastrophic Salmonella outbreak, one of humanity's deadliest, that occurred after the Spanish conquest; the genus Salmonella is part of the family of Enterobacteriaceae. Its taxonomy has the potential to confuse; the genus comprises two species, S. bongori and S. enterica, the latter of, divided into six subspecies: S. e. enterica, S. e. salamae, S. e. arizonae, S. e. diarizonae, S. e. houtenae, S. e. indica.
The taxonomic group contains more than 2500 serotypes defined on the basis of the somatic O and flagellar H antigens. The full name of a serotype is given for example, Salmonella enterica subsp.. Enterica can be abbreviated to Salmonella Typhimurium. Further differentiation of strains to assist clinical and epidemiological investigation may be achieved by antibiotic sensitivity testing and by other molecular biology techniques such as pulsed-field gel electrophoresis, multilocus sequence typing, whole genome sequencing. Salmonellae have been clinically categorized as invasive or noninvasive based on host preference and disease manifestations in humans. Salmonella was first visualized in 1880 by Karl Eberth in the Peyer's patches and spleens of typhoid patients. Four years Georg Theodor Gaffky was able to grow the pathogen in pure culture. A year after that, medical research scientist Theobald Smith discovered what would be known as Salmonella enterica. At the time, Smith was working as a research laboratory assistant in the Veterinary Division of the United States Department of Agriculture.
The department was under the administration of a veterinary pathologist. Salmonella Choleraesuis was thought to be the causative agent of hog cholera, so Salmon and Smith named it "Hog-cholerabacillus"; the name Salmonella was not used until 1900, when Joseph Leon Lignières proposed that the pathogen discovered by Salmon's group be called Salmonella in his honor. Most subspecies of Salmonella produce hydrogen sulfide, which can be detected by growing them on media containing ferrous sulfate, such as is used in the triple sugar iron test. Most isolates exist in two phases, a motile phase I and a nonmotile phase II. Cultures that are nonmotile upon primary culture may be switched to the motile phase using a Craigie tube or ditch plate. RVS broth can be used to enrich for Salmonella species for detection in a clinical sample. Salmonella can be detected and subtyped using multiplex or real-time polymerase chain reactions from extracted Salmonella DNA. Mathematical models of Salmonella growth kinetics have been developed for chicken, pork and melons.
Salmonella reproduce asexually with a cell division interval of 40 minutes. Salmonella species lead predominantly host-associated lifestyles, but the bacteria were found to be able to persist in a bathroom setting for weeks following contamination, are isolated from water sources, which act as bacterial reservoirs and may help to facilitate transmission between hosts. Salmonella is notorious for its ability to survive desiccation and can persist for years in dry environments and foods; the bacteria are not destroyed by freezing. They perish after being heated to 60 °C for 12 min. To protect against Salmonella infection, heating food for at least 10 minutes to an internal temperature of 75 °C is recommended. Salmonella species can be found in the digestive tracts of humans and animals reptiles. Salmonella on the skin of reptiles or amphibians can be passed to people. Food and water can be contaminated with the bacteria if they come in contact with the feces of infected people
Amphibian
Amphibians are ectothermic, tetrapod vertebrates of the class Amphibia. Modern amphibians are all Lissamphibia, they inhabit a wide variety of habitats, with most species living within terrestrial, arboreal or freshwater aquatic ecosystems. Thus amphibians start out as larvae living in water, but some species have developed behavioural adaptations to bypass this; the young undergo metamorphosis from larva with gills to an adult air-breathing form with lungs. Amphibians use their skin as a secondary respiratory surface and some small terrestrial salamanders and frogs lack lungs and rely on their skin, they are superficially similar to lizards but, along with mammals and birds, reptiles are amniotes and do not require water bodies in which to breed. With their complex reproductive needs and permeable skins, amphibians are ecological indicators; the earliest amphibians evolved in the Devonian period from sarcopterygian fish with lungs and bony-limbed fins, features that were helpful in adapting to dry land.
They diversified and became dominant during the Carboniferous and Permian periods, but were displaced by reptiles and other vertebrates. Over time, amphibians shrank in size and decreased in diversity, leaving only the modern subclass Lissamphibia; the three modern orders of amphibians are Anura and Apoda. The number of known amphibian species is 8,000, of which nearly 90% are frogs; the smallest amphibian in the world is a frog from New Guinea with a length of just 7.7 mm. The largest living amphibian is the 1.8 m Chinese giant salamander, but this is dwarfed by the extinct 9 m Prionosuchus from the middle Permian of Brazil. The study of amphibians is called batrachology, while the study of both reptiles and amphibians is called herpetology; the word "amphibian" is derived from the Ancient Greek term ἀμφίβιος, which means "both kinds of life", ἀμφί meaning "of both kinds" and βιος meaning "life". The term was used as a general adjective for animals that could live on land or in water, including seals and otters.
Traditionally, the class Amphibia includes all tetrapod vertebrates. Amphibia in its widest sense was divided into three subclasses, two of which are extinct: Subclass Lepospondyli† Subclass Temnospondyli† Subclass Lissamphibia Salientia: Jurassic to present—6,200 current species in 53 families Caudata: Jurassic to present—652 current species in 9 families Gymnophiona: Jurassic to present—192 current species in 10 families The actual number of species in each group depends on the taxonomic classification followed; the two most common systems are the classification adopted by the website AmphibiaWeb, University of California and the classification by herpetologist Darrel Frost and the American Museum of Natural History, available as the online reference database "Amphibian Species of the World". The numbers of species cited above follows Frost and the total number of known amphibian species as of March 31, 2019 is 8,000, of which nearly 90% are frogs. With the phylogenetic classification, the taxon Labyrinthodontia has been discarded as it is a polyparaphyletic group without unique defining features apart from shared primitive characteristics.
Classification varies according to the preferred phylogeny of the author and whether they use a stem-based or a node-based classification. Traditionally, amphibians as a class are defined as all tetrapods with a larval stage, while the group that includes the common ancestors of all living amphibians and all their descendants is called Lissamphibia; the phylogeny of Paleozoic amphibians is uncertain, Lissamphibia may fall within extinct groups, like the Temnospondyli or the Lepospondyli, in some analyses in the amniotes. This means that advocates of phylogenetic nomenclature have removed a large number of basal Devonian and Carboniferous amphibian-type tetrapod groups that were placed in Amphibia in Linnaean taxonomy, included them elsewhere under cladistic taxonomy. If the common ancestor of amphibians and amniotes is included in Amphibia, it becomes a paraphyletic group. All modern amphibians are included in the subclass Lissamphibia, considered a clade, a group of species that have evolved from a common ancestor.
The three modern orders are Anura and Gymnophiona. It has been suggested that salamanders arose separately from a Temnospondyl-like ancestor, that caecilians are the sister group of the advanced reptiliomorph amphibians, thus of amniotes. Although the fossils of several older proto-frogs with primitive characteristics are known, the oldest "true frog" is Prosalirus bitis, from the Early Jurassic Kayenta Formation of Arizona, it is anatomically similar to modern frogs. The oldest known caecilian is another Early Jurassic species, Eocaecilia micropodia from Arizona; the earliest salamander is Beiyanerpeton jianpingensis from the Late Jurassic of northeastern China. Authorities disagree as to whether Salientia is a superorder that includes the order Anura, or whether
Common toad
The common toad, European toad, or in Anglophone parts of Europe the toad, is an amphibian found throughout most of Europe, in the western part of North Asia, in a small portion of Northwest Africa. It is one of a group of related animals that are descended from a common ancestral line of toads and which form a species complex; the toad is an inconspicuous animal as it lies hidden during the day. It spends the night hunting for the invertebrates on which it feeds, it moves with a slow, ungainly walk or short jumps, has greyish-brown skin covered with wart-like lumps. Although toads are solitary animals, in the breeding season, large numbers of toads converge on certain breeding ponds, where the males compete to mate with the females. Eggs are laid in gelatinous strings in the water and hatch out into tadpoles. After several months of growth and development, these sprout limbs and undergo metamorphosis into tiny toads; the juveniles emerge from the water and remain terrestrial for the rest of their lives.
The common toad seems to be in decline in part of its range, but overall is listed as being of "least concern" in the IUCN Red List of Threatened Species. It is threatened by habitat loss by drainage of its breeding sites, some toads get killed on the roads as they make their annual migrations, it has long been associated in popular literature with witchcraft. The common toad was first given the name Rana bufo by the Swedish biologist Carl Linnaeus in the 10th edition of Systema Naturae in 1758. In this work, he placed all the toads in the single genus Rana, it became apparent that this genus should be divided, in 1768, the Austrian naturalist Josephus Nicolaus Laurenti placed the common toad in the genus Bufo, naming it Bufo bufo. The toads in this genus are included in the true toads. Various subspecies of B. bufo have been recognized over the years. The Caucasian toad is found in the mountainous regions of the Caucasus and was at one time classified as B. b. verrucosissima. It has a larger genome and differs from B. bufo morphologically and is now accepted as Bufo verrucosissimus.
The spiny toad was classified as B. b. spinosus. It is found in France, the Iberean Peninsula and the Maghreb and grows to a larger size and has a spinier skin than its more northern counterparts with which it intergrades, it is now accepted as Bufo spinosus. The Gredos toad, B. b. gredosicola, is restricted to the Sierra de Gredos, a mountain range in central Spain. It has exceptionally large paratoid glands and its colour tends to be blotched rather than uniform, it is now considered to be a synonym of Bufo spinosus. B. Bufo is part of a species complex, a group of related species which cannot be demarcated. Several modern species are believed to form an ancient group of related taxa from preglacial times; these are the Caucasian toad and the Japanese common toad. The European common toad seems to have arisen more recently, it is believed that the range of the ancestral form extended into Asia but that isolation between the eastern and western species complexes occurred as a result of the development of the Central Asian Deserts during the Middle Miocene.
The exact taxonomic relationships between these species remains unclear. A serological investigation into toad populations in Turkey undertaken in 2001 examined the blood serum proteins of Bufo verrucosissimus and Bufo spinosus, it found that the differences between the two were not significant and that therefore the former should be synonymized with the latter. A study published in 2012 examined the phylogenetic relationships between the Eurasian and North African species in the Bufo bufo group and indicated a long evolutionary history for the group. Nine to thirteen million years ago, Bufo eichwaldi, a described species from south Azerbaijan and Iran, split from the main lineage. Further divisions occurred with Bufo spinosus splitting off about five million years ago when the Pyrenees were being uplifted, an event which isolated the populations in the Iberian Peninsula from those in the rest of Europe; the remaining European lineage split into Bufo bufo and Bufo verrucosissimus less than three million years ago during the Pleistocene.
The common toad hybridizes with the natterjack toad or the European green toad. The common toad can reach about 15 cm in length. Females are stouter than males and southern specimens tend to be larger than northern ones; the head is broad with a wide mouth below the terminal snout. There are no teeth; the bulbous, protruding eyes have yellow or copper coloured irises and horizontal slit-shaped pupils. Just behind the eyes are two bulging regions, the paratoid glands, which are positioned obliquely, they contain a noxious substance, used to deter potential predators. The head joins the body without a noticeable neck and there is no external vocal sac; the body is squat and positioned close to the ground. The fore limbs are short with the toes of the fore feet turning inwards. At breeding time, the male develops nuptial pads on the first three fingers, he uses these to grasp the female. The hind legs are short relative to other frogs' legs and the hind feet have long, unwebbed toes. There is no tail; the skin is dry and covered with small wart-like lumps.
The colour is a uniform shade of brown, olive-brown or greyish-brown, sometimes blotched or banded with a darker shade. The common toad tends to be sexually dimorphic with
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