Why is it said that amphibians are found worldwide?

Amphibians are found all over the world, except in Antarctica and Greenland. They are found both on land, and in fresh water. Frogs are the common amphibians. You can find frogs in water, or near places that have water, like ponds and streams. However, some frogs will never enter the water. They live mainly on land. Then, there are some kinds that live in trees. Some frogs are burrowers. Frogs that live in cold places, hibernate during winter time.

            Salamanders are found in North, South and Central America, Europe and Asia, and some species are found in Africa too.

            Caecilians are found in swampy places in most tropical parts of the world.