Science
What is a reptile?
Quick answer
Reptiles are cold-blooded animals with dry, scaly skin. Snakes, lizards, turtles, tortoises and crocodiles are reptiles, and most of them lay eggs on land.
In one sentence
Reptiles are cold-blooded animals with dry, scaly skin that breathe air with lungs, and most lay eggs on land.
Explained
Reptiles are an old group of animals. They include snakes, lizards, turtles, tortoises, crocodiles and alligators. Together there are over 12,000 kinds.
snake
turtle
What do reptiles have in common?
- Dry, scaly skin that keeps water in. A reptile is not slimy.
- Cold-blooded: they cannot make their own body heat. They get warm by basking in the sun and cool down in the shade or a burrow. That is why most reptiles live in warm places and why they slow down in the cold.
- Lungs: reptiles breathe air, even those that spend lots of time in water, such as sea turtles.
- Eggs: most reptiles lay eggs with leathery or hard shells on land. A few, such as some snakes and lizards, give birth to live young.
Reptiles grow throughout life and shed their skin, either in pieces like lizards or in one long piece like many snakes. Many reptiles hatch ready to look after themselves, with little help from their parents. Reptile diets vary: tortoises eat plants, and snakes and crocodiles eat meat. Some snakes are venomous, but most are harmless to people.
Reptiles are often confused with amphibians such as frogs, which have moist skin and start life in water. Unlike mammals, reptiles do not have fur or feed their young milk. Reptiles live on every continent except Antarctica. Long ago, the dinosaurs were relatives of today's reptiles; see dinosaurs.
Examples
| Group | Example | Where |
|---|---|---|
| Lizards | gecko, chameleon, iguana | warm lands |
| Snakes | python, cobra | land, trees, water |
| Turtles and tortoises | green sea turtle | oceans, land |
| Crocodilians | Nile crocodile | rivers and swamps |
Common mistakes
- "Reptiles are slimy." That is amphibians; reptile skin is dry.
- "Cold-blooded means cold." A basking lizard can be quite warm.
- "Frogs and salamanders are reptiles." They are amphibians.
Quick quiz
Reptiles
Check what you know with 4 quick questions.
Question 1 of 4
Which of these is a reptile?
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Related topics
Mammals
Mammals are warm-blooded animals with hair or fur that feed their babies milk. Most give birth to live young. Humans, lions, whales and bats are all mammals.
Living things
Living things are organisms that grow, feed, get rid of waste, sense the world and reproduce. Plants, animals, fungi and bacteria are all alive.
Habitats
A habitat is the natural home of a living thing, where it finds the food, water, shelter and space it needs to survive.
Amphibians
Amphibians are cold-blooded animals with thin, moist skin that live part of their lives in water and part on land. Frogs, toads, newts and salamanders are amphibians.
Dinosaurs
Dinosaurs were reptiles that lived on land from about 230 million years ago until most died out 66 million years ago. Birds are their living descendants.
Adaptation
An adaptation is a feature or behaviour that helps a living thing survive where it lives. A polar bear's thick fur and a cactus's spines are adaptations.