warmblooded

More than 252 million years ago, mammal ancestors became warm-blooded to survive mass extinction: The skeleton of a therapsid dicynodont _Lystrosaurus_. FlickrToday mammals and birds are the only true warm-blooded animals. They are called endotherms, meaning they produce their body heat internally. Endotherm animals are the opposite to ectotherms which get their heat from an … [Read more...] about More than 252 million years ago, mammal ancestors became warm-blooded to survive mass extinction | The Conversation