It's about the many other things animals can do with their incredible rear ends - from sitting to stinging, from attracting a mate to taking a breath. And it's about how different those rear ends are. Some are brightly colored. A few can sting. Looking at different animals' hindquarters can give you information about the ways those animals live, both alone and together.
Some people wear makeup on their faces.
Female baboons and male mandrills look like they've put makeup on their butts. Baboons, which are found all over Africa, live in large troops made up of smaller family groups. Each family group has one male leader, up to ten females, and their young. The oldest and strongest males are the rulers. Each male mates with all the adult females in his family group.