Mammals are a group of vertebrate animals constituting the class Mammalia, and characterized by the presence of mammary glands which in females produce milk for feeding their young, a neocortex, fur or hair, and three middle ear bones.
Scientific name: Mammalia
Scale: pangolin worldwildlife.org
What five characteristics do mammals have in common? Mammals have hair or fur; are warm-blooded; most are born alive; the young are fed milk produced by the mother’s mammary glands; and they have a more complex brain than other animals.