Reptiles

Reptiles are ectothermic animals—often called “cold-blooded”—and rely on external heat sources like the sun to regulate their body temperature.

Their scaly skin helps prevent them from drying out on land.

They breathe through lungs and have strong sense organs. For example, crocodiles rely on sharp vision, while turtles use their keen sense of smell, and snakes detect scents with their tongues.

Most reptiles reproduce by laying amniotic eggs with leathery or hard shells that can survive on land. While some lizards and snakes can also give birth to live young, highlighting the diversity of reproductive strategies among reptiles.

Reptiles are tetrapods—vertebrates that originally had four limbs—even though some, like snakes, have lost them through evolution.

Living reptiles are further classified into four main groups: squamates, such as snakes and lizards; crocodilians, including alligators and crocodiles; testudines, like turtles and tortoises; and sphenodonts, such as the tuatara.