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. There are nearly 2,700 species of frogs known. They are divided into 16 families, with 9 occurring in North America. Frogs like to be in or near water.