Answer: Mammals are a group of animals (vertebrates) that have backbones and hair or fur. They are warm-blooded (endothermic), and they have four-chambered hearts. They also feed their young with milk from the mother's body. The young of most mammals are born alive.
Step-by-step explanation:
Mammals (from Latin mamma, 'breast') are a group of vertebrate animals constituting the class Mammalia (/məˈmeɪliə/), and characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or hair, and three middle ear bones.
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