The Drill is native to tropical forests of West and Central Africa (limited areas of Nigeria, Cameroon and Equatorial Guinea). It is related to Mandrills and Baboons.
The adult breeding male, above, is much bigger than the female and has a pink chin and, like the Mandrill, has blue, mauve and red rump and genitals.
The female, above, doesn't have a pink chin or colourful rump. They live in large, mixed groups.