At the primate exhibit at the zoo, you notice a slew of monkeys dangling from branches by their tails. the information plaque notes that they are colobus, macaques, and baboons. when you read this, you immediately seek out the zookeeper to complain about the error because

The answer is: None of the monkeys have prehensile tails.

Prehensile tails are the type of tyles which structure are adapted in a way that allow the animal to grab on hard objects and hang on to it.
 colobus, macaques, and baboons physical structures are very similar to human. So rather than seeking protection/shelter on top of trees, they occasionally use caves just like early humans.