Summary:
- Mammals are a class of endothermic vertebrates.
- They have four limbs and produce amniotic eggs.
- Female mammals have mammary glands.
- The glands produce milk after the birth of offspring.
- Mammals have hair or fur.
- It insulates the body and can be used for sensing and communicating.
- Most mammals share several other traits.
- The traits in the following list are typical of, but not necessarily unique to, mammals.