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reptiliaЗначение термина reptilia в knolikreptilia - reptilia reptilia - Reptiles, a class of vertebrates. Includes many orders, the living ones being Chelonia (turtles and tortoises), Rhyncocephalia (the tuatara), Squamata (lizards and snakes), Grocodilia (crocodiles); and the entirely extinct ones being, amongst others, Ornithischia and Saurischia (both dinosaurs), Pterodactyla, Ichthyo-sauria, Plesiosauria, Therapsida (the ancestors of the mammals). Reptiles are poikilothermic tetrapods, mostly living and reproducing entirely on land, though some have become aquatic. They were the dominant terrestrial animals in the Mesozoic. Modern ones are distinguished from Amphibia by horny skin, metanephric kidney, and by the embryo being enclosed in an eggshell and having a protective amnion and an allantois; and from birds and mammals by absence of the special features, such as feathers or hair, of those groups. But in the fossil record there are intermediates between them and both amphibia and mammals, and no sharp dividing line is possible. The distinction for most fossils is made on the structure of the vertebral column, and other skeletal features. Рядом со словом reptilia в knolik
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