Science Buddies: "Ask an Expert"

Hi,
Not really sure how this works but can anyone answer my question.
Why are baboons classed as lesser apes while mandrills are monkeys?
They are relatively the same size but mandrills are tail-less where as baboons have tails.
If you ask me baboons look more monkey-like than mandrills.
If any replies are left please include qualifications as I only want a real scientist’s reasoning.

Hello, welcome to the Ask an Expert forums!

This is a space where students, parents, and educators can receive advice and/or guidance on their science fair projects. Are you working on a science project? If so, providing more information about your project will ensure that the response you receive is helpful and precise. If not, there are other resources that may better fit your needs.

Hello,
I am not working on a project just trying to “ask an expert”. If my question cannot be answered here then no worries, appreciate your time none the less.