196 Introduction to Reptiles

What you’ll learn to do: Identify characteristics of reptiles

Reptiles are tetrapod animals in the class Reptilia. This class includes 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.

In more recent years, scientists have discovered that some reptiles are more closely related to birds than they are to other reptiles (e.g., crocodiles are more closely related to birds than they are to lizards). For this reason, many modern scientists prefer to consider the birds part of Reptilia as well. In this course, we will study them separately.