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.
Watch a salamander move, or even a crocodile: Its body twists from side to side with each step. Now compare to how a mammal walks. (Or a dinosaur, for that matter.) Instead of swinging their whole body side to side, the spine flexes up and down, and the legs swing directly forward and backward. OK, so marine mammals evolved from creatures specialized for walking, with spines that flex up and down but not side to side. That means that to transmit the force from their spine to the water, the tail needs to be horizontal, not vertical. Written Jun 29, 2014 â¢ View Upvotes â¢ Not for Reproduction.