There are several distinct traits that make mammals different from other animals, with the most significant ones being that ...

Vertebrates and invertebrates can be sorted into smaller groups. Vertebrates, for example, are divided into mammals, birds, reptiles, amphibians and fish. Mammals are warm-blooded animals with ...

To answer the question of why mammals have five fingers, we must first understand why tetrapod (Greek for "four-footed") ...