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65-580: An alligator , or colloquially gator , is a large reptile in the genus Alligator of the family Alligatoridae of the order Crocodilia . The two extant species are the American alligator ( A. mississippiensis ) and the Chinese alligator ( A. sinensis ). Additionally, several extinct species of alligator are known from fossil remains. Alligators first appeared during the late Eocene epoch about 37 million years ago. The name "alligator"

130-562: A clade ( monophyletic group) including birds, though the precise definition of this clade varies between authors. Others prioritize the clade Sauropsida , which typically refers to all amniotes more closely related to modern reptiles than to mammals . The earliest known proto-reptiles originated from the Carboniferous period, having evolved from advanced reptiliomorph tetrapods which became increasingly adapted to life on dry land. The earliest known eureptile ("true reptile")

195-447: A temnospondyl ). A series of footprints from the fossil strata of Nova Scotia dated to 315  Ma show typical reptilian toes and imprints of scales. These tracks are attributed to Hylonomus , the oldest unquestionable reptile known. It was a small, lizard-like animal, about 20 to 30 centimetres (7.9 to 11.8 in) long, with numerous sharp teeth indicating an insectivorous diet. Other examples include Westlothiana (for

260-400: A "death roll", spinning or convulsing wildly until bite-sized chunks are torn off. Critical to the alligator's ability to initiate a death roll, the tail must flex to a significant angle relative to its body. An alligator with an immobilized tail cannot perform a death roll. Most of the muscle in an alligator's jaw evolved to bite and grip prey. The muscles that close the jaws are powerful, but

325-405: A Louisiana swamp in 1987. Alligators are raised commercially for their meat and their skin, which when tanned is used for the manufacture of luggage , handbags , shoes, belts , and other leather items. Alligators also provide economic benefits through the ecotourism industry. Visitors may take swamp tours, in which alligators are a feature. Their most important economic benefit to humans may be

390-451: A breeding pair of Chinese alligators. Large male alligators are solitary territorial animals. Smaller alligators can often be found in large numbers close to each other. The largest of the species (both males and females) defend prime territory; smaller alligators have a higher tolerance for other alligators within a similar size class. Alligators move on land by two forms of locomotion, referred to as "sprawl" and "high walk". The sprawl

455-495: A length of 1.8 m (6 ft). The mating season is in late spring. In April and May, alligators form so-called "bellowing choruses". Large groups of animals bellow together for a few minutes a few times a day, usually one to three hours after sunrise. The bellows of male American alligators are accompanied by powerful blasts of infrasound . Another form of male display is a loud head-slap. In 2010, on spring nights alligators were found to gather in large numbers for group courtship,

520-437: A meal by up to four times its basal metabolic rate. Alligators also have highly folded mucosa in the lining of the intestines to further aid in the absorption of nutrients. The folds result in greater surface area for the nutrients to be absorbed through. Alligators also have complex microbiomes that are not fully understood yet, but can be attributed to both benefits and costs to the animal. These microorganisms can be found in

585-555: A meal during brumation will begin a process called autophagy , where the animal begins to consume its fat reserves to maintain its body weight until it can acquire a sufficient meal. There is also fluctuation in the level of bacterial taxa populations in the alligator's microbial community between seasons which helps the alligator cope with different rates of feeding and activity. Like other crocodilians, alligators have an armor of bony scutes. The dermal bones are highly vascularised and aid in calcium balance, both to neutralize acids while

650-495: A section of the clade Amniota : The section that is left after the Mammalia and Aves have been hived off. It cannot be defined by synapomorphies , as is the proper way. Instead, it is defined by a combination of the features it has and the features it lacks: reptiles are the amniotes that lack fur or feathers. At best, the cladists suggest, we could say that the traditional Reptilia are 'non-avian, non-mammalian amniotes'. Despite

715-569: A tiny gecko, Sphaerodactylus ariasae , which can grow up to 17 mm (0.7 in) to the saltwater crocodile , Crocodylus porosus , which can reach over 6 m (19.7 ft) in length and weigh over 1,000 kg (2,200 lb). In the 13th century, the category of reptile was recognized in Europe as consisting of a miscellany of egg-laying creatures, including "snakes, various fantastic monsters, lizards, assorted amphibians, and worms", as recorded by Beauvais in his Mirror of Nature . In

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780-471: A two-storey building of the 19th century, built in the late XIX - early XX centuries, located on the territory of the zoo. Since 2015, the museum has been open to the public and everyone. In the central and side halls there is an exposition devoted to the history of the Moscow Zoo and a natural science permanent exposition. The collection of the museum includes more than 10,000 zoo coat of arms from all over

845-783: Is 360 kg (790 lb) and 4 m (13 ft), but they sometimes grow to 4.4 m (14 ft) long and weigh over 450 kg (990 lb). The largest ever recorded, found in Louisiana, measured 5.84 m (19.2 ft). The Chinese alligator is smaller, rarely exceeding 2.1 m (7 ft) in length. Additionally, it weighs considerably less, with males rarely over 45 kg (100 lb). Adult alligators are black or dark olive-brown with white undersides, while juveniles have bright yellow or whitish stripes which sharply contrast against their dark hides, providing them additional camouflage amongst reeds and wetland grasses. No average lifespan for an alligator has been measured. One of

910-465: Is a forward movement with the belly making contact with the ground and is used to transition to "high walk" or to slither over wet substrate into water. The high walk is an up-on-four-limbs forward motion used for overland travel with the belly well up from the ground. Alligators have also been observed to rise up and balance on their hind legs and semi-step forward as part of a forward or upward lunge. However, they can not walk on their hind legs. Although

975-479: Is equivalent to the more common definition of Sauropsida, which Modesto and Anderson synonymized with Reptilia, since the latter is better known and more frequently used. Unlike most previous definitions of Reptilia, however, Modesto and Anderson's definition includes birds, as they are within the clade that includes both lizards and crocodiles. General classification of extinct and living reptiles, focusing on major groups. The cladogram presented here illustrates

1040-516: Is found in only the Yangtze River valley and parts of adjacent provinces and is extremely endangered, with only a few dozen believed to be left in the wild. Far more Chinese alligators live in zoos around the world than can be found in the wild. Rockefeller Wildlife Refuge in southern Louisiana has several in captivity in an attempt to preserve the species. Miami MetroZoo in Florida also has

1105-594: Is likely an anglicized form of el lagarto , the Spanish term for "the lizard", which early Spanish explorers and settlers in Florida called the alligator. Early English spellings of the name included allagarta and alagarto . Alligators and caimans split in North America during the early Tertiary or late Cretaceous (about 53 million to about 65 million years ago). The Chinese alligator split from

1170-630: The American alligator about 33 million years ago and probably descended from a lineage that crossed the Bering land bridge during the Neogene . The modern American alligator is well represented in the fossil record of the Pleistocene . The alligator's full mitochondrial genome was sequenced in the 1990s. The full genome , published in 2014, suggests that the alligator evolved much more slowly than mammals and birds. The genus Alligator belongs to

1235-861: The Reptile Database . The study of the traditional reptile orders, customarily in combination with the study of modern amphibians , is called herpetology . Reptiles have been subject to several conflicting taxonomic definitions. In Linnaean taxonomy , reptiles are gathered together under the class Reptilia ( / r ɛ p ˈ t ɪ l i ə / rep- TIL -ee-ə ), which corresponds to common usage. Modern cladistic taxonomy regards that group as paraphyletic , since genetic and paleontological evidence has determined that birds (class Aves), as members of Dinosauria , are more closely related to living crocodilians than to other reptiles, and are thus nested among reptiles from an evolutionary perspective. Many cladistic systems therefore redefine Reptilia as

1300-418: The amniotic egg . The terms Sauropsida ("lizard faces") and Theropsida ("beast faces") were used again in 1916 by E.S. Goodrich to distinguish between lizards, birds, and their relatives on the one hand (Sauropsida) and mammals and their extinct relatives (Theropsida) on the other. Goodrich supported this division by the nature of the hearts and blood vessels in each group, and other features, such as

1365-417: The apex predator throughout their distribution. In this role as a top predator, it may determine the abundance of prey species, including turtles and nutrias. As humans encroach into their habitat, attacks are few but not unknown. Alligators, unlike the large crocodiles , do not immediately regard a human upon encounter as prey, but may still attack in self-defense if provoked. Alligators generally mature at

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1430-483: The crocodile , with minor differences in morphology and enzyme activity. Alligators have a two-part stomach, with the first smaller portion containing gastroliths . It is believed this portion of the stomach serves a similar function as it does in the gizzard of some species of birds, to aid in digestion. The gastroliths work to grind up the meal as alligators will take large bites or swallow smaller prey whole. This process makes digestion and nutrient absorption easier once

1495-814: The subfamily Alligatorinae , which is the sister taxon to Caimaninae (the caimans ). Together, these two subfamilies form the family Alligatoridae . The cladogram below shows the phylogeny of alligators. Caimaninae Ceratosuchus burdoshi † Hassiacosuchus haupti † Navajosuchus mooki † Wannaganosuchus brachymanus † Arambourgia gaudryi † Allognathosuchus polyodon † Allognathosuchus wartheni † Procaimanoidea kayi † Alligator prenasalis † Alligator mcgrewi † Alligator olseni † Alligator sinensis Chinese alligator Alligator thomsoni † Alligator mefferdi † Alligator mississippiensis American alligator An average adult American alligator's weight and length

1560-1741: The "family tree" of reptiles, and follows a simplified version of the relationships found by M.S. Lee, in 2013. All genetic studies have supported the hypothesis that turtles are diapsids; some have placed turtles within Archosauromorpha, though a few have recovered turtles as Lepidosauromorpha instead. The cladogram below used a combination of genetic (molecular) and fossil (morphological) data to obtain its results. Synapsida ( mammals and their extinct relatives) [REDACTED] † Millerettidae [REDACTED] † Eunotosaurus † Lanthanosuchidae [REDACTED] † Pareiasauromorpha [REDACTED] † Procolophonoidea [REDACTED] † Captorhinidae [REDACTED] † Paleothyris † Araeoscelidia [REDACTED] † Claudiosaurus [REDACTED] † Younginiformes [REDACTED] † Kuehneosauridae [REDACTED] Rhynchocephalia ( tuatara and their extinct relatives) [REDACTED] Squamata ( lizards and snakes ) [REDACTED] [REDACTED] † Eosauropterygia [REDACTED] † Placodontia [REDACTED] † Sinosaurosphargis † Odontochelys † Proganochelys Testudines ( turtles ) [REDACTED] † Choristodera [REDACTED] † Prolacertiformes [REDACTED] † Rhynchosauria [REDACTED] † Trilophosaurus [REDACTED] Archosauriformes ( crocodiles , birds , dinosaurs and extinct relatives) [REDACTED] [REDACTED] The placement of turtles has historically been highly variable. Classically, turtles were considered to be related to

1625-453: The 18th century, the reptiles were, from the outset of classification, grouped with the amphibians . Linnaeus , working from species-poor Sweden , where the common adder and grass snake are often found hunting in water, included all reptiles and amphibians in class "III – Amphibia" in his Systema Naturæ . The terms reptile and amphibian were largely interchangeable, reptile (from Latin repere , 'to creep') being preferred by

1690-484: The French. J.N. Laurenti was the first to formally use the term Reptilia for an expanded selection of reptiles and amphibians basically similar to that of Linnaeus. Today, the two groups are still commonly treated under the single heading herpetology . It was not until the beginning of the 19th century that it became clear that reptiles and amphibians are, in fact, quite different animals, and P.A. Latreille erected

1755-656: The Moscow Zoo has been chairman of all zoos in Russia since the Soviet period, it is a national training center. This was founded in 2017 by the current director Svetlana Akulova and Björn Stenvers . Outdoors: Indoors (Exotarium): From 2001 to 2014, the Moscow Zoo Dolphinarium  [ ru ] operated on the grounds of the zoo's old territory. The exhibit was dismantled following unsanitary conditions and improper husbandry procedures. Directors of

1820-406: The alligator has a heavy body and a slow metabolism , it is capable of short bursts of speed, especially in very short lunges. Alligators' main prey are smaller animals they can kill and eat with a single bite. They may kill larger prey by grabbing it and dragging it into the water to drown. Alligators consume food that cannot be eaten in one bite by allowing it to rot or by biting and then performing

1885-657: The anapsid condition has been found to occur so variably among unrelated groups that it is not now considered a useful distinction. By the early 21st century, vertebrate paleontologists were beginning to adopt phylogenetic taxonomy, in which all groups are defined in such a way as to be monophyletic ; that is, groups which include all descendants of a particular ancestor. The reptiles as historically defined are paraphyletic , since they exclude both birds and mammals. These respectively evolved from dinosaurs and from early therapsids, both of which were traditionally called "reptiles". Birds are more closely related to crocodilians than

1950-543: The animal cannot breathe underwater and to provide calcium for eggshell formation. Alligators have muscular, flat tails that propel them while swimming. The two kinds of white alligators are albino and leucistic . These alligators are practically impossible to find in the wild. They could survive only in captivity and are few in number. The Aquarium of the Americas in New Orleans has leucistic alligators found in

2015-777: The animals into attacking. In Florida, feeding wild alligators at any time is illegal. If fed, the alligators will eventually lose their fear of humans and will learn to associate humans with food. The type of food eaten by alligators depends upon their age and size. When young, alligators eat fish, insects, snails , crustaceans , and worms . As they mature, progressively larger prey is taken, including larger fish such as gar , turtles, and various mammals, particularly nutrias and muskrats, as well as birds, deer, and other reptiles. Their stomachs also often contain gizzard stones . They will even consume carrion if they are sufficiently hungry. In some cases, larger alligators are known to ambush dogs, Florida panthers and black bears , making them

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2080-446: The area to 18 hectares (44 acres). In 1933 Vera Chaplina , a naturalist and future writer, created the "green platform", a special enclosure for young animals where different cubs that their mothers refused to feed were not only raised, but also taught to live peacefully together. This experiment aroused great interest among visitors, and for many years the "green platform" remained one of the Moscow Zoo's main attractions. In 1990,

2145-421: The class Batracia (1825) for the latter, dividing the tetrapods into the four familiar classes of reptiles, amphibians, birds, and mammals. The British anatomist T.H. Huxley made Latreille's definition popular and, together with Richard Owen , expanded Reptilia to include the various fossil " antediluvian monsters", including dinosaurs and the mammal-like ( synapsid ) Dicynodon he helped describe. This

2210-664: The control of nutrias and muskrats . Alligator meat is also consumed by humans. While there are rules of thumb for distinguishing alligators from crocodiles, all of them admit exceptions. Such general rules include: Reptile See text for extinct groups. Reptiles , as commonly defined, are a group of tetrapods with an ectothermic ('cold-blooded') metabolism and amniotic development . Living reptiles comprise four orders : Testudines ( turtles ), Crocodilia ( crocodilians ), Squamata ( lizards and snakes ), and Rhynchocephalia (the tuatara ). As of May 2023, about 12,000 living species of reptiles are listed in

2275-554: The early proposals for replacing the paraphyletic Reptilia with a monophyletic Sauropsida , which includes birds, that term was never adopted widely or, when it was, was not applied consistently. When Sauropsida was used, it often had the same content or even the same definition as Reptilia. In 1988, Jacques Gauthier proposed a cladistic definition of Reptilia as a monophyletic node-based crown group containing turtles, lizards and snakes, crocodilians, and birds, their common ancestor and all its descendants. While Gauthier's definition

2340-453: The fetus develops within the mother, using a (non-mammalian) placenta rather than contained in an eggshell . As amniotes, reptile eggs are surrounded by membranes for protection and transport, which adapt them to reproduction on dry land. Many of the viviparous species feed their fetuses through various forms of placenta analogous to those of mammals , with some providing initial care for their hatchlings. Extant reptiles range in size from

2405-461: The food reaches the second portion of the stomach. Once an alligator's meal has been processed it will move on to the second portion of the stomach which is highly acidic. The acidity of the stomach has been observed to increase once digestion begins. This is due to the increase in CO 2 concentration of the blood, resulting from the right to left shunting of the alligators heart. The right to left shunt of

2470-413: The former tend to produce males and the latter, females. The baby alligator's egg tooth helps it get out of its egg during hatching time. The natural sex ratio at hatching is five females to one male. Females hatched from eggs incubated at 30 °C (86 °F) weigh significantly more than males hatched from eggs incubated at 34 °C (93 °F). The mother defends the nest from predators and assists

2535-419: The hatchlings to water. She will provide protection to the young for about a year if they remain in the area. Adult alligators regularly cannibalize younger individuals, though estimates of the rate of cannibalism vary widely. In the past, immediately following the outlawing of alligator hunting , populations rebounded quickly due to the suppressed number of adults preying upon juveniles, increasing survival among

2600-497: The heart in alligators means the circulatory system will recirculate blood through the body instead of back to the lungs. The re-circulation of blood leads to higher CO 2 concentration as well as lower oxygen affinity. There is evidence to suggest that there is increased blood flow diverted to the stomach during digestion to facilitate an increase in CO 2 concentration which aids in increasing gastric acid secretions during digestion. The alligator's metabolism will also increase after

2665-467: The high surface area of the mucosa folds of the intestines, as well as throughout the digestive tract. Benefits include better total health and stronger immune system. However alligators are still vulnerable to microbial infections despite the immune boost from other microbiota. During brumation the process of digestion experiences changes due to the fasting most alligators experience during these periods of inactivity. Alligators that go long enough without

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2730-466: The hypothesis that turtles belong to a separate clade within Sauropsida , outside the saurian clade altogether. The origin of the reptiles lies about 310–320 million years ago, in the steaming swamps of the late Carboniferous period, when the first reptiles evolved from advanced reptiliomorphs . The oldest known animal that may have been an amniote is Casineria (though it may have been

2795-419: The inspired air must move back out the same way it came in. In contrast, air in alligator lungs makes a circuit, moving in only one direction through the parabronchi . The air first enters the outer branch, moves through the parabronchi, and exits the lung through the inner branch. Oxygen exchange takes place in extensive vasculature around the parabronchi. The alligator has a similar digestive system to that of

2860-441: The largest alligator population. The majority of American alligators inhabit Florida and Louisiana, with over a million alligators in each state. Southern Florida is the only place where both alligators and crocodiles live side by side. American alligators live in freshwater environments, such as ponds , marshes , wetlands , rivers , lakes , and swamps , as well as in brackish water . When they construct alligator holes in

2925-508: The late 19th century, a number of definitions of Reptilia were offered. The biological traits listed by Lydekker in 1896, for example, include a single occipital condyle , a jaw joint formed by the quadrate and articular bones, and certain characteristics of the vertebrae . The animals singled out by these formulations, the amniotes other than the mammals and the birds, are still those considered reptiles today. The synapsid/sauropsid division supplemented another approach, one that split

2990-508: The latter are to the rest of extant reptiles. Colin Tudge wrote: Mammals are a clade , and therefore the cladists are happy to acknowledge the traditional taxon Mammalia ; and birds, too, are a clade, universally ascribed to the formal taxon Aves . Mammalia and Aves are, in fact, subclades within the grand clade of the Amniota. But the traditional class Reptilia is not a clade. It is just

3055-796: The living reptiles, there are many diverse groups that are now extinct , in some cases due to mass extinction events . In particular, the Cretaceous–Paleogene extinction event wiped out the pterosaurs , plesiosaurs , and all non-avian dinosaurs alongside many species of crocodyliforms and squamates (e.g., mosasaurs ). Modern non-bird reptiles inhabit all the continents except Antarctica. Reptiles are tetrapod vertebrates , creatures that either have four limbs or, like snakes, are descended from four-limbed ancestors. Unlike amphibians , reptiles do not have an aquatic larval stage. Most reptiles are oviparous , although several species of squamates are viviparous , as were some extinct aquatic clades  –

3120-473: The moment considered a reptiliomorph rather than a true amniote ) and Paleothyris , both of similar build and presumably similar habit. However, microsaurs have been at times considered true reptiles, so an earlier origin is possible. Moscow Zoo The Moscow Zoo or Moskovsky Zoopark ( Russian : Московский зоопарк ) is a 21.5-hectare (53-acre) zoo , the largest in Russia . The Moscow Zoo

3185-436: The muscles for opening their jaws are weak. As a result, an adult human can hold an alligator's jaws shut bare-handed. It is common to use several wraps of duct tape to prevent an adult alligator from opening its jaws when being handled or transported. Alligators are generally timid towards humans and tend to walk or swim away if one approaches. This may encourage people to approach alligators and their nests, which can provoke

3250-805: The oldest recorded alligator lives was that of Saturn , an American alligator who was hatched in 1936 in Mississippi and spent nearly a decade in Germany before spending the majority of his life at the Moscow Zoo , where he died at the age of 83 or 84 on 22 May 2020. Another one of the oldest lives on record is that of Muja , an American alligator who was brought as an adult specimen to the Belgrade Zoo in Serbia from Germany in 1937. Although no valid records exist about his date of birth, as of 2012, he

3315-422: The other euryapsids, and given the older name Parapsida. Parapsida was later discarded as a group for the most part (ichthyosaurs being classified as incertae sedis or with Euryapsida). However, four (or three if Euryapsida is merged into Diapsida) subclasses remained more or less universal for non-specialist work throughout the 20th century. It has largely been abandoned by recent researchers: In particular,

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3380-416: The primitive anapsid reptiles. Molecular work has usually placed turtles within the diapsids. As of 2013, three turtle genomes have been sequenced. The results place turtles as a sister clade to the archosaurs , the group that includes crocodiles, non-avian dinosaurs, and birds. However, in their comparative analysis of the timing of organogenesis , Werneburg and Sánchez-Villagra (2009) found support for

3445-438: The reptiles into four subclasses based on the number and position of temporal fenestrae , openings in the sides of the skull behind the eyes. This classification was initiated by Henry Fairfield Osborn and elaborated and made popular by Romer 's classic Vertebrate Paleontology . Those four subclasses were: The composition of Euryapsida was uncertain. Ichthyosaurs were, at times, considered to have arisen independently of

3510-546: The so-called "alligator dances". In summer, the female builds a nest of vegetation where the decomposition of the vegetation provides the heat needed to incubate the eggs. The sex of the offspring is determined by the temperature in the nest and is fixed within seven to 21 days of the start of incubation. Incubation temperatures of 30 °C (86 °F) or lower produce a clutch of females; those of 34 °C (93 °F) or higher produce entirely males. Nests constructed on leaves are hotter than those constructed on wet marsh, so

3575-789: The structure of the forebrain. According to Goodrich, both lineages evolved from an earlier stem group, Protosauria ("first lizards") in which he included some animals today considered reptile-like amphibians , as well as early reptiles. In 1956, D.M.S. Watson observed that the first two groups diverged very early in reptilian history, so he divided Goodrich's Protosauria between them. He also reinterpreted Sauropsida and Theropsida to exclude birds and mammals, respectively. Thus his Sauropsida included Procolophonia , Eosuchia , Millerosauria , Chelonia (turtles), Squamata (lizards and snakes), Rhynchocephalia , Crocodilia , " thecodonts " ( paraphyletic basal Archosauria ), non- avian dinosaurs , pterosaurs , ichthyosaurs , and sauropterygians . In

3640-466: The wetlands, they increase plant diversity and provide habitat for other animals during droughts. They are, therefore, considered an important species for maintaining ecological diversity in wetlands. Farther west, in Louisiana, heavy grazing by nutrias and muskrats is causing severe damage to coastal wetlands. Large alligators feed extensively on nutrias, and provide a vital ecological service by reducing nutria numbers. The Chinese alligator currently

3705-479: The world, hundreds of paintings, sculptures and drawings by the masters of Russian animalistics, such as Vasily Vatagin , Alexei Komarov , Vadim Trofimov, Andrei Marts and Alexei Tsvetkov . The Moscow Zoo has her own educational institute and research center. In addition to full-training for zoo staff and teachers, there is a continuing education program for zoo and aquarium staff, veterinarians , teachers and volunteers, as well as courses in zoo psychology. Since

3770-590: The years following Gauthier's paper. The first such new definition, which attempted to adhere to the standards of the PhyloCode , was published by Modesto and Anderson in 2004. Modesto and Anderson reviewed the many previous definitions and proposed a modified definition, which they intended to retain most traditional content of the group while keeping it stable and monophyletic. They defined Reptilia as all amniotes closer to Lacerta agilis and Crocodylus niloticus than to Homo sapiens . This stem-based definition

3835-429: The young alligators. Alligators, much like birds, have been shown to exhibit unidirectional movement of air through their lungs. Most other amniotes are believed to exhibit bidirectional, or tidal breathing. For a tidal breathing animal, such as a mammal, air flows into and out of the lungs through branching bronchi which terminate in small dead-end chambers called alveoli . As the alveoli represent dead-ends to flow,

3900-536: The zoo was renovated. Notable additions include a new main entrance in the shape of a large rock castle, and a footbridge that connected the old (1864) and new (1926) properties of the zoo. In addition, the zoo was expanded once more. New exhibits were opened including a sea aquarium, an aviary, a creatures of the night exhibit, a sea lion exhibit and a section aimed at children. The Moscow zoo has over 7,500 animals representing about 1,000 species and covers an area of about 21.5 hectares (53 acres). Founded in 2008 in

3965-650: Was Hylonomus , a small and superficially lizard-like animal which lived in Nova Scotia during the Bashkirian age of the Late Carboniferous , around 318  million years ago . Genetic and fossil data argues that the two largest lineages of reptiles, Archosauromorpha (crocodilians, birds, and kin) and Lepidosauromorpha (lizards, and kin), diverged during the Permian period. In addition to

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4030-592: Was close to the modern consensus, nonetheless, it became considered inadequate because the actual relationship of turtles to other reptiles was not yet well understood at this time. Major revisions since have included the reassignment of synapsids as non-reptiles, and classification of turtles as diapsids. Gauthier 1994 and Laurin and Reisz 1995's definition of Sauropsida defined the scope of the group as distinct and broader than that of Reptilia, encompassing Mesosauridae as well as Reptilia sensu stricto . A variety of other definitions were proposed by other scientists in

4095-556: Was founded in 1864 by professor-biologists, K.F. Rulje, S.A. Usov and A.P. Bogdanov, from the Moscow State University . In 1919, the zoo was nationalized. In 1922, the ownership was transferred to the Government of Moscow and has remained under their control ever since. The zoo had an area of 10 hectares (25 acres) when it first opened, with 286 animals. In 1926, the zoo was expanded to adjacent lands, increasing

4160-497: Was in his 80s and possibly the oldest alligator living in captivity. Alligators are native only to the United States and China . American alligators are found in the southeast United States : all of Florida and Louisiana ; the southern parts of Georgia , Alabama , and Mississippi ; coastal South and North Carolina ; East Texas , the southeast corner of Oklahoma , and the southern tip of Arkansas . Louisiana has

4225-627: Was not the only possible classification scheme: In the Hunterian lectures delivered at the Royal College of Surgeons in 1863, Huxley grouped the vertebrates into mammals , sauroids, and ichthyoids (the latter containing the fishes and amphibians). He subsequently proposed the names of Sauropsida and Ichthyopsida for the latter two groups. In 1866, Haeckel demonstrated that vertebrates could be divided based on their reproductive strategies, and that reptiles, birds, and mammals were united by

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