The eggs do not have shells and so must be laid in water or a damp environment to keep from drying out. Amphibians go through a two-stage life cycle. When an amphibian hatches it is in a gilled larval form. In frogs and toads this larva is called a tadpole. After a few weeks or months the larvae transform into the adult form of a frog or salamander, however it may still take a few years to become mature.
Biologists divide amphibians into three major groups or Orders.
There is no actual body contact. As I said before the water serves as a protector but also the larva are sometimes eaten by fish. Frogs make up a group that is known to go back over two million years. Frogs are the first backboned animal to live on land. There are seven different families of frogs.