When did frogs evolve?
In the Devonian period, it was hotter and drier on Earth than usual. That’s because a lot of the land was gathered together into one continent, Gondwana. So a lot of smaller seas were drying up. The fish in these seas needed another way to live.
Why do frogs eat insects?
What’s the life cycle of frogs?
Are frogs cold-blooded?
How do frogs reproduce?
Being able to survive on land was a big advantage for frogs, and they did pretty well. But frogs still had to live close to water. They lay their eggs and their sperm in the water to make new tadpoles, and the tadpoles have to live in water.
Can frogs breathe through their skin?
Another reason frogs need to stay near the water is that frogs need to have wet skin most of the time. Frog hearts don’t pump blood with oxygen in it to their bodies very well. Frog hearts mix blood with oxygen in it and blood without. To make up for this problem, frogs also can breathe air through their skins – but only if their skin is wet.