About Amphibians
Amphibians are the oldest tetrapods, or four-legged animals, and appeared on land for the first time over 350,000,000 years ago. Salamander-like creatures emerged from the water, having descended from fishes that evolved bones in their fins for navigating underwater obstacles. They are present and numerous on every continent except Antarctica.
Today, amphibians are represented by three major "orders". Of the more than 6,600 described...
