Reptile
Reptile
Reptiles are a group of vertebrates comprising today's turtles, crocodilians, snakes, amphisbaenians, lizards, tuatara, and their extinct relatives. The study of these traditional reptile orders, historically combined with that of modern amphibians, is called herpetology.
Characteristics[edit]
Because they are defined paraphyletically, not all reptiles are closely related. They do share some morphological and physiological characteristics.
Cold-bloodedness[edit]
The majority of reptile species are ectothermic, which means that their internal body temperature depends on the ambient environment temperature.
Scales[edit]
Reptiles are known for their scales. Reptile scales vary in size, shape, and texture, and are typically keratinous, but there are some exceptions, such as the scales of turtles and crocodiles.
Heart[edit]
The heart has two atria and one ventricle. The ventricle is incompletely separated into two by a wall, giving the reptile heart a unique structure.
Classification[edit]
Reptiles are classified into four orders:
- Testudines: Turtles
- Squamata: Lizards, snakes and amphisbaenians
- Crocodilia: Crocodiles, gavials, caimans, and alligators
- Rhynchocephalia: Tuatara
Evolution[edit]
Reptiles first appear in the fossil record 315 million years ago and were the dominant animals during the Mesozoic era, which lasted for 270 million years until the extinction of the dinosaurs.
See also[edit]
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Reptile[edit]
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TWC Wildlife Centre Stewart Nimmo MRD 8910
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Saltwater Crocodile (Maximo)
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Florida Box Turtle Digon3
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Rhinechis scalaris cropped
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Reptile 003d
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Mosasaur Discovery
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Captorhinus aguti
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Varanodon 1DB
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Bearded Dragon Skeleton
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Milleretta BW flipped
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Lanthanosuchus NT flipped
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