<p>Mammals are warm-blooded vertibrates. The vast majority of them are viviparous, meaning that they begin development as an embryo in their mother's womb. Humans belong to this class. In this section, you'll learn about mammals of every shape and size, where they live, how they reproduce and what their habits are.</p>


Mammals are warm-blooded vertibrates. The vast majority of them are viviparous, meaning that they begin development as an embryo in their mother's womb. Humans belong to this class. In this section, you'll learn about mammals of every shape and size, where they live, how they reproduce and what their habits are.