DetailsCrocodile _Desigend by YahooJAPAN ( http://www.thingiverse.com/thing:182118/#files ) _Crocodiles (subfamily Crocodylinae) or true crocodiles are large aquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. Crocodylinae, in which all its members are considered true crocodiles, is classified as a biological subfamily. A broader sense of the term crocodile, Crocodylidae that includes Tomistoma, is not used in this article. The term crocodile here applies only to the species within the subfamily of Crocodylinae. The term is sometimes used even more loosely to include all extant members of the order Crocodilia, which includes Tomistoma, the alligators and caimans (family Alligatoridae), the gharials (family Gavialidae), and all other living and fossil Crocodylomorpha.Although they appear to be similar to the untrained eye, crocodiles, alligators and the gharial belong to separate biological families. The gharial having a narrow snout is easier to distinguish, while morphological differences are more difficult to spot in crocodiles and alligators. The most obvious external differences are visible in the head with crocodiles having narrower and longer heads, with a more V-shaped than a U-shaped snout compared to alligators and caimans. Another obvious trait is the upper and lower jaws of the crocodiles are the same width, and teeth in the lower jaw fall along the edge or outside the upper jaw when the mouth is closed; therefore all teeth are visible unlike an alligator; which possesses small depressions in the upper jaw where the lower teeth fit into. Also when the crocodile's mouth is closed, the large fourth tooth in the lower jaw fits into a constriction in the upper jaw. For hard-to-distinguish specimens, the protruding tooth is the most reliable feature to define the family that the species belongs to. _Crocodiles have more webbing on the toes of the hind feet and can better tolerate saltwater due to specialized salt glands for filtering out salt, which are present but non-functioning in alligators. Another trait that separates crocodiles from other crocodilians is their much higher levels of aggression.Crocodile size, morphology, behavior and ecology somewhat differs between species. However, they have many similarities in these areas as well. All crocodiles are semiaquatic and tend to congregate in freshwater habitats such as rivers, lakes, wetlands and sometimes in brackish water and saltwater. They are carnivorous animals, feeding mostly on vertebrates such as fish, reptiles, birds and mammals, and sometimes on invertebrates such as molluscs and crustaceans, depending on species and age. All crocodiles are tropical species that unlike alligators, are very sensitive to cold. They first separated from other crocodilians during the Eocene epoch, about 55 million years ago. Many species are at the risk of extinction, some being classified as critically endangered. _A crocodile’s physical traits allow it to be a successful predator. Its external morphology is a sign of its aquatic and predatory lifestyle. Its streamlined body enables it to swim swiftly, it also tucks its feet to the side while swimming, which makes it faster by decreasing water resistance. They have webbed feet which, though not used to propel the animal through the water, allow them to make fast turns and sudden moves in the water or initiate swimming. Webbed feet are an advantage in shallower water, where the animal sometimes moves around by walking. Crocodiles have a palatal flap, a rigid tissue at the back of the mouth that blocks the entry of water. The palate has a special path from the nostril to the glottis that bypasses the mouth. The nostrils are closed during submergence. Like other archosaurs, crocodilians are diapsid, although their post-temporal fenestrae are reduced. The walls of the braincase are bony, but lack supratemporal and postfrontal bones.Their tongues are not free, but held in place by a membrane that limits movement; as a result, crocodiles are unable to stick out their tongues.Crocodiles have smooth skin on their bellies and sides, while their dorsal surfaces are armoured with large osteoderms. The armoured skin has scales and is thick and rugged, providing some protection. They are still able to absorb heat through this armour, as a network of small capillaries allows blood through the scales to absorb heat. Crocodilian scales have pores believed to be sensory in function, analogous to the lateral line in fishes. They are particularly seen on their upper and lower jaws. Another possibility is that they are secretory, as they produce an oily substance which appears to flush mud off. _Crocodiles have acute senses, an evolutionary advantage that makes them successful predators. The eyes, ears and nostrils are located on top of the head, allowing the crocodile to lie low in the water, almost totally submerged and hidden from prey.Crocodiles have very good night vision, and are mostly nocturnal hunters. They use the disadvantage of most prey animals' poor nocturnal vision, to their advantage. The light receptors in crocodilians’ eyes include both cones and numerous rods, so it is assumed all crocodilians can see colors.The term "Crocodile tears" (and equivalents in other languages) refers to a false, insincere display of emotion such as a hypocrite crying fake tears of grief. It is derived from an ancient anecdote that crocodiles weep in order to lure their prey, or that they cry for the victims they are eating, first told in the Bibliotheca by Photios.The story is repeated in bestiaries such as De bestiis et aliis rebus. This tale was first spread widely in English in the stories of the travels of Sir John Mandeville in the 14th century, and appears in several of Shakespeare's plays. In fact, crocodiles can and do generate tears, but they do not actually cry.
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SKU 10000487 Length [mm] 150 Width [mm] 51.16 Height [mm] 23.34 Volume [cm³] 41.5 Area [cm²] 108.87