English Amphibian Cited by user Joeisamama on 03 Dec 2020 Amphibians are ectothermic, tetrapod vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia.
English Amphibian Cited by user Cwmhiraeth on 15 Aug 2012 The earliest amphibians evolved in the Devonian Period from sarcopterygian fish with lungs and bony-limbed fins, features that were helpful in adapting to dry land.