Q Which is the chordate class considered an evidence of the transition of the vertebrates from the aquatic to the dry land environment?
The amphibians are totally aquatic in the partially terrestrial animals and larval stage as adults and for these facts they are considered intermediate beings in the evolutionary passage of vertebrates from the aquatic to the dry land habitat. Amphibians are also the first tetrapod animals that are the first with two pair of limbs a typical feature of terrestrial vertebrates. The name "amphibian" comes from the double life (aquatic as partially terrestrial as adults and larvae) of these animals.