"of reptiles, but are now agreed to have evolved independently, being degenerate feathers. An example of a scaled mammal is the pangolin. Its scales are made of keratin and are used for protection, similar to an armadillo's armor. They have been convergently evolved, being unrelated to the animal's distant reptile ancestors, except that they use a similar gene. On the other hand, the musky rat-kangaroo, has scales on its feet and tail. The precise nature of its purported scales has not been studied in detail, but they appear to be structurally different from pangolin scales. Anomalures also have scales on"
"distinguishes them from reptile scales paleontologically. Genetically, the same genes involved in tooth and hair development in mammals are also involved in scale development. True cosmoid scales can only be found on the Sarcopterygians. The inner layer of the scale is made of lamellar bone. On top of this lies a layer of spongy or vascular bone and then a layer of dentine-like material called cosmine. The upper surface is keratin. The coelacanth has modified cosmoid scales that lack cosmine and are thinner than true cosmoid scales. Ganoid scales can be found on gars (family Lepisosteidae), bichirs, and reedfishes (family"
"of feather keratin in the early stages of development of American alligator scales. This type of keratin, previously thought to be specific to feathers, is suppressed during embryological development of the alligator and so is not present in the scales of mature alligators. The presence of this homologous keratin in both birds and crocodilians indicates that it was inherited from a common ancestor. This may suggest that crocodilian scales, bird and dinosaur feathers, and pterosaur pycnofibres are all developmental expressions of the same primitive archosaur skin structures; suggesting that feathers and pycnofibers could be homologous. Several non-avian dinosaurs had feathers"
"aquatic forms and pangolin (which has the testes just below the skin). It appears to be an ancestral character for this group, yet other orders generally lack this as an ancestral feature, with the probable exception of Primates. The clade Scrotifera is based on evidence from molecular phylogenetics. The monophyly of the group is well supported, but there is some debate about the internal order, with Pegasoferae being an alternative to that shown in the following cladogram. Scrotifera Scrotifera is a clade of placental mammals that comprises the following orders and their common ancestors: Chiroptera, Carnivora, Pholidota, Perissodactyla and Cetartiodactyla,"
"Ground pangolin The ground pangolin (""Smutsia temminckii""), also known as Temminck's pangolin or Cape pangolin, is one of four species of pangolins which can be found in Africa, and the only one in southern and eastern Africa. The animal was named for the Dutch zoologist Coenraad Jacob Temminck. As a group, pangolins are among the most critically endangered animals in the world. Although their outward appearance is reptilian, pangolins are mammals. Pangolins are almost completely covered in overlapping, protective scales, which makes up about 20% of their body weight. The scales are composed of keratin, the same material that forms"
"Squamata Squamata is the largest order of reptiles, comprising lizards, snakes and amphisbaenians (worm lizards), which are collectively known as squamates or scaled reptiles. With over 10,000 species, it is also the second-largest order of extant (living) vertebrates, after the perciform fish, and roughly equal in number to the Saurischia (one of the two major groups of dinosaurs). Members of the order are distinguished by their skins, which bear horny scales or shields. They also possess movable quadrate bones, making it possible to move the upper jaw relative to the neurocranium. This is particularly visible in snakes, which are able"
"Firoloida Firoloida is a monotypic genus of pelagic marine gastropod mollusc in the family Pterotracheidae, with the only species in the genus being Firoloida desmarestia. This shell-less mollusc is found in tropical and sub-tropical waters in the epipelagic zone of the world's oceans. Both genus and species were first described in 1817 by the French artist and naturalist Charles Alexandre Lesueur. He named the species in honour of the French zoologist Anselme Gaëtan Desmarest but made an error in spelling the specific name and called the mollusc ""F. demarestia"". Subsequent authors corrected this to ""F. desmarestia"", but according to the"
"Coelenterata Coelenterata is an obsolete term encompassing the animal phyla Cnidaria (coral animals, true jellies, sea anemones, sea pens, and their allies) and Ctenophora (comb jellies). The name comes from the Greek """"koilos"""" (""hollow"") and """"enteron"""" (""intestine""), referring to the hollow body cavity common to these two phyla. They have very simple tissue organization, with only two layers of cells (external and internal), and radial symmetry. Some examples are corals, which are typically colonial, and hydra, jelly fish and sea anemones which are solitary. Coelenterata lack a specialized circulatory system relying instead on diffusion across the tissue layers. All coelenterates"
"Ferae The Ferae are a clade of mammals, consisting of the orders Carnivora (over 260 species, around the globe) and Pholidota (eight species of pangolins in tropical Africa and Asia). Pangolins do not exhibit morphological traits typically associated with carnivorans (wolves, cats, seals, and so on), and were thought to be the closest relatives of Xenarthra (armadillos and sloths), but DNA research conducted in the 2000s found the close relationship to carnivorans. Several extinct orders, relatives of the Pholidota, such as Creodonts, are members of Ferae as well. An alternate name, Ostentoria, has also been proposed for a grouping of"
"the Carnivora and Pholidota. According to recent studies (reflected in the diagram below), the closest relatives of Ferae are Perissodactyla (horses, tapirs, and rhinos) and Cetartiodactyla (which combines Artiodactyla—camels, pigs, ruminants and hippos—with Cetacea—whales and dolphins). An alternate phylogeny (less supported) holds that the closest relatives to the Ferae are the Perissodactyla and Chiroptera (bats), not Cetartiodactyla. Ferae together with Perissodactyla has been called Zooamata. Ferae, Perissodactyla, and Chiroptera together has been called Pegasoferae. Ferae The Ferae are a clade of mammals, consisting of the orders Carnivora (over 260 species, around the globe) and Pholidota (eight species of pangolins in"
"Cheilostomata Cheilostomata (accepted name Cheilostomatida), an order of Bryozoa in the class Gymnolaemata, are exclusively marine, colonial invertebrate animals. Cheilostome colonies are composed of calcium carbonate and grow on a variety of surfaces, including rocks, shells, seagrass and kelps. The colony shapes range from simple encrusting sheets to erect branching and even unattached forms. As in other bryozoan groups, each colony is composed of a few to thousands of individual polypides. Each individual has a U-shaped gut, and no respiratory, circulatory, or nerve system. Unique among bryozoans, cheilostome polypides are housed in a box-shaped zooids, which do not grow larger"
"in standby, which can be activated when required. Tooth replacement slows significantly and eventually stops as the animal grows old. The skin of crocodilians is thick and cornified, and is clad in non-overlapping scales known as scutes, arranged in regular rows and patterns. These scales are continually being produced by cell division in the underlying layer of the epidermis, the stratum germinativum, and the surface of individual scutes sloughs off periodically. The outer surface of the scutes consists of the relatively rigid beta-keratin while the hinge region between the scutes contains only the more pliable alpha-keratin. Many of the scutes"
"Pilosa The order Pilosa is a group of placental mammals, extant today only in the Americas. It includes the anteaters and sloths, including the extinct ground sloths, which became extinct about 10,000 years ago. The name comes from the Latin word for ""hairy"". Pilosans are good examples of ecological harmony. Anteaters, for example, feed lightly and for a short time at any one ant nest, allowing the colony to regrow easily. Also, sloths' fur is home to many insects, as well as a type of algae that helps camouflage the sloths. The biogeographic origins of the Pilosa are still unclear,"
"Pachydermata Placcyderma (from two Greek words παχύς ""pachys"", ""thick"" and δέρμα ""derma"", ""skin"", meaning 'thick skin') is an obsolete order of mammals described by Gottlieb Storr, Georges Cuvier and others, at one time recognized by many systematists. Because it is polyphyletic, the order is no longer in use, but it is important in the history of systematics. Outside strict biological classification, the term ""pachyderm"" remains commonly used to describe elephants, rhinoceroses, and hippopotamuses. Cuvier's Pachydermata included the three families of mammals he called Proboscidiana, Pachydermata Ordinaria, and Solipedes, all herbivorous. They are now divided into the Proboscidea (represented among living"
"Paenungulata Paenungulata is a clade that groups three extant mammal orders: Proboscidea (including elephants), Sirenia (sea cows, including dugongs and manatees), and Hyracoidea (hyraxes). At least two more orders are known only as fossils, namely Embrithopoda and Desmostylia (desmostylians, however, have been placed in Perissodactyla by a 2014 cladistic analysis, and the taxonomic placement of embrithopods has also been questioned though recently supported). Each of these extinct orders was as unique in its members' ways as the surviving orders. Embrithopods were rhinoceros-like herbivorous mammals with plantigrade feet, and desmostylians were hippopotamus-like amphibious animals. Their walking posture and diet have been"
"Echidna Echidnas (), sometimes known as spiny anteaters, belong to the family Tachyglossidae in the monotreme order of egg-laying mammals. The four extant species, together with the platypus, are the only surviving members of the order Monotremata, and are the only living mammals that lay eggs. The diet of some species consists of ants and termites, but they are not closely related to the true anteaters of the Americas. Echidnas live in Australia and New Guinea. Echidnas evolved between 20 and 50 million years ago, descending from a platypus-like monotreme. This ancestor was aquatic, but echidnas adapted to life on"
"ungulates; and anatomical characters support the affinities of ""pachyderm"" mammals to each other and to other ungulates. Pachydermata Placcyderma (from two Greek words παχύς ""pachys"", ""thick"" and δέρμα ""derma"", ""skin"", meaning 'thick skin') is an obsolete order of mammals described by Gottlieb Storr, Georges Cuvier and others, at one time recognized by many systematists. Because it is polyphyletic, the order is no longer in use, but it is important in the history of systematics. Outside strict biological classification, the term ""pachyderm"" remains commonly used to describe elephants, rhinoceroses, and hippopotamuses. Cuvier's Pachydermata included the three families of mammals he called"
"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. Lizards and some frogs have somewhat similar osteoderms forming bony deposits in the dermis, but this is an example of convergent evolution with similar structures having arisen independently in diverse vertebrate"
"delicacy. Echidna Echidnas (), sometimes known as spiny anteaters, belong to the family Tachyglossidae in the monotreme order of egg-laying mammals. The four extant species, together with the platypus, are the only surviving members of the order Monotremata, and are the only living mammals that lay eggs. The diet of some species consists of ants and termites, but they are not closely related to the true anteaters of the Americas. Echidnas live in Australia and New Guinea. Echidnas evolved between 20 and 50 million years ago, descending from a platypus-like monotreme. This ancestor was aquatic, but echidnas adapted to life"
"scales of all reptiles have an epidermal component (what one sees on the surface), but many reptiles, such as crocodilians and turtles, have osteoderms underlying the epidermal scale. Such scales are more properly termed scutes. Snakes, tuataras and many lizards lack osteoderms. All reptilian scales have a dermal papilla underlying the epidermal part, and it is there that the osteoderms, if present, would be formed. Birds' scales are found mainly on the toes and metatarsus, but may be found further up on the ankle in some birds. The scales and scutes of birds were thought to be homologous to those"
"a secret agent. The choice of a platypus was inspired by media underuse, as well as to exploit the animal's striking appearance. As a character, Perry has been well received by both fans and critics. Platypus The platypus (""Ornithorhynchus anatinus""), sometimes referred to as the duck-billed platypus, is a semiaquatic egg-laying mammal endemic to eastern Australia, including Tasmania. Together with the four species of echidna, it is one of the five extant species of monotremes, the only mammals that lay eggs instead of giving birth to live young. The animal is the sole living representative of its family (Ornithorhynchidae) and"
"Camelid Camelids are members of the biological family Camelidae, the only currently living family in the suborder Tylopoda. The extant members of this group are: dromedary camels, Bactrian camels, wild Bactrian camels, llamas, alpacas, vicuñas, and guanacos. Camelids are even-toed ungulates classified in the order Cetartiodactyla, along with pigs, whales, deer, cattle, antelope, and many others. Camelids are large, strictly herbivorous animals with slender necks and long legs. They differ from ruminants in a number of ways. Their dentition show traces of vestigial central incisors in the incisive bone, and the third incisors have developed into canine-like tusks. Camelids also"
"with bony cores, or osteoderms. This type of skin is best known in the ceratosaur ""Carnotaurus"", which has been preserved with extensive skin impressions. The coelurosaur lineages most distant from birds had feathers that were relatively short and composed of simple, possibly branching filaments. Simple filaments are also seen in therizinosaurs, which also possessed large, stiffened ""quill""-like feathers. More fully feathered theropods, such as dromaeosaurs, usually retain scales only on the feet. Some species may have mixed feathers elsewhere on the body as well. ""Scansoriopteryx"" preserved scales near the underside of the tail, and ""Juravenator"" may have been predominantly scaly"
"pangolins, armadillos, and anteaters. He believed it was most likely a primitive, isolated member of ""Edentata"", a group in which he included aardvarks, pangolins, and Xenarthra (sloths, armadillos, and anteaters). He rejected some alternatives, such as a close affinity to aardvarks or the possibility that the material assigned to ""Plesiorycteropus"" did not in fact represent a single animal. Bryan Patterson, who revised tubulidentates (the order of which the aardvark is the only living representative) in the 1970s, accepted ""Plesiorycteropus"" as a member of the group, dismissing many similarities with pangolins and other animals as convergent. However, he placed it as"
"Koala The koala (""Phascolarctos cinereus"", or, inaccurately, koala bear) is an arboreal herbivorous marsupial native to Australia. It is the only extant representative of the family Phascolarctidae and its closest living relatives are the wombats, which comprise the family Vombatidae.. The koala is found in coastal areas of the mainland's eastern and southern regions, inhabiting Queensland, New South Wales, Victoria, and South Australia. It is easily recognisable by its stout, tailless body and large head with round, fluffy ears and large, spoon-shaped nose. The koala has a body length of and weighs . Pelage colour ranges from silver grey to"
"primitive form of dermal armour in reptiles. The term is also used to describe the heavy armour of the armadillo and the extinct ""Glyptodon"", and is occasionally used as an alternative to scales in describing snakes or certain fishes, such as sturgeons, shad, herring, and menhaden. The turtle's shell is covered by scutes formed mostly of keratin. They are built similarly to horn, beak, or nail in other species. The tarsometatarsus and toes of most birds are covered in two types of scales. Large scutes run along the dorsal side of the tarsometatarsus and toes, whereas smaller scutellae run along"
"than three major cladistic branches of placential mammals: Meridiungulata (if xenungulates are the closest relatives), Laurasiatheria (if dinoceratans are the closest relatives) and Afrotheria (if embrithopods are the closest relatives). Pyrotheria Pyrotheria is an order of extinct meridiungulate mammals. These mastodon-like ungulates include the genera ""Baguatherium"", ""Carolozittelia"", ""Colombitherium"", ""Gryphodon"", ""Propyrotherium"", ""Proticia"", and ""Pyrotherium"". They had the appearance of large, digitigrade, tapir-like mammals with relatively short, slender limbs and five-toed feet with broad, flat phalanges. Their fossils are restricted to Paleocene through Oligocene deposits of Brazil, Peru and Argentina. Some experts place the clade Xenungulata (which contains several genera, including ""Carodnia"")"
"scales. The main defining feature that distinguishes this species from other monitors is its lack of a parietal eye and the lack of a hemibaculum. The species is presumed to be semiaquatic, but little is known about its wild habits, as most information and study comes from captive individuals. The Varanidae are a family of carnivorous and frugivorous monitor lizards, which contains one extant genus (""Varanus"") with 73 species, including the Komodo dragon. They can be characterized by their thick skin and small, rounded scales. The ventral scales are slightly larger than the dorsal scales. They have a parietal eye"
"together with several extinct groups indicated (†) below, though this idea has fallen out of favor since it was determined that cimolestids were not placental mammals. A 2015 study has supported close affinities between pangolins and the extinct group Creodonta, as well as many former Cimolestans (""Cimolestes"" itself was recovered as a far more basal mammal). All species of living pangolin had been assigned to the genus ""Manis"" until the late 2000s, when research prompted the splitting of extant pangolins into three genera: ""Manis"", ""Phataginus"", and ""Smutsia"". Pangolin Pangolins or scaly anteaters are mammals of the order Pholidota (from the"
"in a horny epidermis, making it watertight and enabling reptiles to live on dry land, in contrast to amphibians. Compared to mammalian skin, that of reptiles is rather thin and lacks the thick dermal layer that produces leather in mammals. Exposed parts of reptiles are protected by scales or scutes, sometimes with a bony base, forming armor. In lepidosaurians, such as lizards and snakes, the whole skin is covered in overlapping epidermal scales. Such scales were once thought to be typical of the class Reptilia as a whole, but are now known to occur only in lepidosaurians. The scales found"
"species only by three species of elephants), the Perissodactyla (odd-toed ungulates, including horses, tapirs and rhinoceroses), the Suina (pigs and peccaries), the Hippopotamidae, and the Hyracoidea (hyraxes). Cuvier himself defined Pachydermata as ""animals with hoofs, nonruminants"", whereas Storr had described it as ""mammals with hoofs with more than two toes"". Cuvier added horses to the order. One naturalist, Delabere Pritchett Blaine, has speculated that: Although the former order of Pachydermata is often described as an artificial grouping of unrelated mammals, it was recognised by notable zoologists, including Charles Darwin, as a grade of hoofed mammals to the exception of other"
"by restricted openings in the bases of the sclerites; chancellorid sclerites were probably made of aragonite, which is not found in demosponges, and the only sponges that use aragonite are the sclerosponges, whose soft bodies cover hard, often massive skeletons made of either aragonite or calcite, another form of calcium carbonate; sponges have loosely bound-together skins called pinacoderms, which are only one cell thick, while the skins of chancellorids were much thicker and shows signs of connective structures called belt desmosomes. In their opinion the presence of belt desmosomes made chancellorids members of the Epitheliazoa, the next higher taxon above"
"Reptile scale Reptile skin is covered with scutes or scales which, along with many other characteristics, distinguish reptiles from animals of other classes. Scales are made of alpha and beta-keratin and are formed from the epidermis (contrary to fish, in which the scales are formed from the dermis). They may be ossified or tubercular, as in the case of lizards, or modified elaborately, as in the case of snakes. Lizard scales vary in form from tubercular to platelike, or imbricate (overlapping). These scales, which on the surface are composed of horny (keratinized) epidermis, may have bony plates underlying them; these"