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Amphibians

Frogs

An adult European common frogAn adult European common frog Frogs are short, tail-less amphibians with long hind legs and smooth skin. They spend most of their time in water. Their very long legs and streamlined bodies mean that they can make huge leaps and swim quickly. Adult frogs are carnivorous, feeding on insects, snails or worms. Larger frogs will also eat fish, other frogs and even small mammals. There are about 5800 species of frog—around 90% of all amphibian species. They include the toads, which are actually warty-skinned types of frog. All frogs and toads belong to the Anura order.


Frog spawnFrog spawn

Frog spawn

Most frogs lay thousands of jelly-like eggs, called frog spawn, in ponds, lakes or streams. It consists of tiny embryos surrounded by layers of jelly. Many frogs lay their spawn in clumps, while toads often lay their spawn in long chains on top of pond weed. The jelly protects the embryos and keeps them moist, while allowing oxygen in and carbon dioxide out. It also provides food for the growing embryos. After about a month, the young start to hatch out and feed on what is left of their eggs. 



Tadpoles

Frogs that live in colder climates often spend winter in hibernation at the bottom of their ponds, breathing through their skins.

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