How tall are monkeys when their fully grown?

There's no single answer to this question because monkeys come in a wide variety of sizes! Here's why:

* Species: Just like humans, different monkey species have different sizes. Some are very small, like the pygmy marmoset (around 5-6 inches tall). Others are quite large, like the mandrill (up to 3 feet tall).

* Sex: In some species, males are larger than females.

* Diet and Environment: A monkey's size can also be influenced by its diet and the environment it lives in.

So, it's impossible to give you a general answer about how tall monkeys are when fully grown. You'd need to specify the species of monkey you're interested in.

Would you like to know the size of a specific monkey species?