Above, a female mandrill and a great mandrill; middle, a young mandrill and a little baboon; below, a drill mandrill and a young drill mandrill. Coloured etching by S. Milne and Turvey.

Licence: Public Domain Mark

Credit: Above, a female mandrill and a great mandrill; middle, a young mandrill and a little baboon; below, a drill mandrill and a young drill mandrill. Coloured etching by S. Milne and Turvey. Wellcome Collection. Source: Wellcome Collection.