Definition of float in the AudioEnglish.org Dictionary. Meaning of float. What does float mean? Proper usage and pronunciation (in phonetic transcription) of the word float. Information about float in the AudioEnglish.org dictionary, synonyms and antonyms.
Mammals evolved from a group of mammal-like reptiles called the Synapsids, specifically the Therapsids, in the Triassic period, around 250 million years ago.
Restoration of Procynosuchus, a member of the cynodont group, which includes the ancestors of mammals. The evolution of mammals has passed through many stages since the first appearance of their synapsid ancestors in the late Carboniferous period. The most ancestral forms in the class Mammalia are the egg-laying mammals in the subclass Prototheria.