Amniota is a clade of Tetrapods distinguished by there ability to lay a hard shelled (amniotic) egg. They appeared during the Carboniferous. Amniotes were the first tetrapods to lay eggs on land, and the eggs were filled with amniotic fluid. The Amniotes evolved from amphibians like the Anthracosaurs. Surviving amniotes include the reptiles, birds, and mammals of today.
Advertisement