About Mammals
Mammals are a group of warm-blooded vertebrates characterized by the presence of mammary glands which in females produce milk for feeding their young. They have hair or fur, a neocortex (a region of the brain), and three middle ear bones.
Mammals range in size from tiny bumblebee bats to enormous blue whales, and they inhabit a wide variety of environments from the arctic tundra to tropical rainforests.