9781422283479

There might be a good reason why aliens in books and movies so often look like reptiles. With their scaly skin and cold blood, this group of animals has some the weirdest and scariest species on Earth. The reptile family includes small, darting lizards, slithery snakes, turtles, and hard-shelled tortoises. Giant crocodiles with rows of sharp teeth are reptiles, too. Reptiles are one of the Earth’s main and oldest groups of animals. They lived alongside the dinosaurs that dominated the planet millions of years ago.

Today there are about 6,500 different species, or kinds, of reptiles. The reptile family can be divided into four main groups: snakes, lizards, turtles, and crocodiles. Over half of all living reptiles are lizards. Most of the rest are snakes.

7 Lizards are the largest family of reptiles. Chameleons, geckos, iguanas (shown here), and skinks are all types of lizards, too.

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