Introduction to Amphibians

Amphibian types

The word amphibian comes from the Greek word for “double-life,” referring to the fact that amphibians start life in water breathing through gills before maturing into lung-breathing land animals, although most never stray too far from water. The class Amphibia is composed of only 3 orders. The order Anura, a word that refers to tailless amphibians, includes frogs and toads ( see Table: Similarities and Differences Between Frogs and Toads). This is the largest order, with more than 3,500 species. The order Caudata, or amphibians with tails—salamanders, newts, and sirens—has about 375 species ( see Table: Some Common Salamanders and Newts). The Gymnophiona order is made up of caecilians: legless, tailless amphibians that spend most of their time burrowing. It has about 160 species.