Characteristics of mammals. Bibliography . . . . . . . . . . . . . . . . A mammal is a vertebrate that feeds its young on the mother's milk. There are about 4,000 kinds of mammals. Many of them are among the most familiar of all animals.
People are mammals too.
All mammals share some basic body parts. These characteristics include certain features of their skin and hair, skeleton and internal organ system. Some mammals have a thick coat of hair to provide warmth. Almost all mammals have seven bones in their neck. What Mammals Eat Most mammals are herbivorous, that is, they eat plants.