Deep in the rainforests of southern Cameroon, Gabon, Equatorial Guinea and Congo lives one of Africa's most striking primates: the mandrill. Adult males are instantly recognizable by their vivid blue-and-red facial markings.
Weighing up to 35 kilograms, male mandrills hold a record: they are the world's largest monkeys, excluding great apes such as gorillas and chimpanzees, which belong to a different family.
Mandrills are also known for their enormous groups. In Gabon, hordes have been recorded with more than a thousand individuals in a single troop — the largest gathering of wild non-human primates ever documented.
Sources: Encyclopaedia Britannica, Africa Geographic.
