Reptiles

The distinguishing characteristic of amniotes, a shelled egg with an amniotic membrane, allowed them to venture onto land.

Modern amniotes, which includes mammals, reptiles, and birds, evolved from an amphibian ancestor approximately 340 million years ago.

Reptiles are ectothermic tetrapods that lay shelled eggs on land and possess scaly skin and lungs.

Dinosaurs and pterosaurs diverged from early amniotes and dominated the Mesozoic Era.

Class Reptilia, amniotes that are neither mammals nor birds, has four living clades: Crocodilia, Sphenodontia, Squamata, and Testudine.