Frogs are amphibians, but what is an amphibian?
• Frogs are members of the class Amphibia. They make up 85 percent of living species in this class and are widespread and successful on all continents except Antarctica. • Frogs are cold-blooded vertebrate animals that lack scales, have squat bodies, long muscular hind legs, and typically lack tails. • The word “amphibian” is derived from the Greek “amphi” and “bios” and translates into “double-life”. This refers to the fact that frogs return to the water to breed, develop, and the transform (or metamorphose) to live a mainly terrestrial existence. What changes do frogs go through during metamorphosis? • There are several striking changes during metamorphosis as tadpoles mature into frogs. • The long gut of a tadpole, used to digest plants, shrinks in length and the intestines become shorter to prepare for a carnivorous diet on land as a frog. • The mouth changes from a small oval opening to a wide structure with an extendible tongue attached to the front of the mouth. • A tadpole uses
