Reptiles are vertebrates that have dry scaly skin, lungs, and lay eggs on land unlike amphibians. The earliest known reptile fossil dates back 350 million years ago in the Carboniferous period. The Mesozoic era was dominated by reptiles until 65 million years ago when many went extinct at the end of the Cretaceous period. Reptiles have well-developed lungs, a double circulatory system, efficient excretion and strong limbs that allowed them to thrive on land.

1. Birds & Reptiles Edwin Canseco, Janeth, Cruz Mr. Buchmann Biology 5*

4. FORM & FUNCION IN REPTILES Clip art Reptiles have a well developed lungs; a double loop circulatory system, a water conserving excretory system; strong limbs; internal fertilization; and shelled, terrestrial eggs are the other adaptation that have contribute to the success of reptiles on land(1).