What Are the Major Characteristics of Reptiles?

Reptile species vary dramatically in size and appearance. A reptile can be as small as a tiny gecko that is less than an inch long or as big as a crocodile, which can weigh more than a ton.

  1. Identification

    • Reptiles are vertebrates (they have a backbone), have scaly skin and lay eggs. They have four legs or are descended from creatures with four legs.

    Temperature Regulation

    • Reptiles are ectotherms, meaning they cannot produce their own body heat. Their body temperature changes with the temperature of their environment. Strictly speaking, though, they are not "cold-blooded," because when they are in a hot environment, they can maintain a high body temperature.

    Types

    • There are four types (orders) of reptiles: testudines contains turtles and tortoises; squamata contains lizards and snakes; crocodylia contains crocodiles and alligators; and rhynchocephalia contains only two species of the lizard-like tuataras, which live off the coast of New Zealand.