Edwin Giesbers / Head portrait of male Mandrill (Mandrillus sphinx) Captive. Apenheul zoo; the Netherlands.

Mark Bowler / Mandrill (Mandrillus sphinx) male showing aggression, captive

Anup Shah / Young male wild Mandrill (Mandrillus sphinx) in tree. Gallery forest during dry season. Lope National Park, Gabon. July 2008.

Anup Shah / Mature male wild Mandrill (Mandrillus sphinx) walking through gallery forest during dry season. Lope National Park, Gabon. July 2008.

Anup Shah / Mature Male wild Mandrill (Mandrillus sphinx) walking through gallery forest during dry season. Lope National Park, Gabon. July 2008.

Anup Shah / Wild mature male Mandrill (Mandrillus sphinx) walking through gallery forest during dry season. Lope National Park, Gabon. July 2008.

Fiona Rogers / Wild mature male mandrill (Mandrillus sphinx) in gallery forest during dry season. Lope National Park, Gabon. June 2008.

Karl Ammann / Male mandrill portrait (Mandrillus sphinx), Central Africa.

Bernard Walton / Mandrill large male in forest {Mandrillus sphinx} Gabon, Central Africa

Pete Oxford / Mandrill head portrait male {Mandrillus sphinx} occurs West Africa forests

Anup Shah / Male Mandrill head portrait, native to West Africa

Cyril Ruoso / Mandrill (Mandrillus sphinx) adult male, Gabon

Cyril Ruoso / Mandrill (Mandrillus sphinx) close-up portrait of an adult male picking his nose, Gabon

Thomas Marent / Mandrill (Mandrillus sphinx) male in defensive posture, Lekedi Natural Preserve, Gabon

Thomas Marent / Mandrill (Mandrillus sphinx) male, Lekedi Natural Preserve, Gabon

Thomas Marent / Mandrill (Mandrillus sphinx) male, Lekedi Natural Preserve, Gabon

Thomas Marent / Mandrill (Mandrillus sphinx) male in defensive posture, Lekedi Natural Preserve, Gabon

Thomas Marent / Mandrill (Mandrillus sphinx) males in tall grass, Lekedi Natural Preserve, Gabon

Thomas Marent / Mandrill (Mandrillus sphinx) male, Lekedi Natural Preserve, Gabon

Roland Seitre / Mandrill (Mandrillus sphinx) male, native to central Africa

Eric Baccega / Mandrill (Mandrillus sphinx) silhouetted, walking along tree branch, Conkouati-Douli National Park, Republic of Congo, Africa.

Uri Golman / Female Mandrill (Mandrillus sphinx) in a tree, Gabon.

Uri Golman / Mandrill (Mandrillus sphinx) male face portrait, Gabon. September.

Uri Golman / Mandrill (Mandrillus sphinx) male portrait, Gabon. September.

Uri Golman / Mandrill (Mandrillus sphinx) mother and young in forest, Gabon. January.

Doug Gimesy / Portrait of a Mandrill male Mandrillus sphinx). Captive, at Melbourne Zoo, Parkville, Victoria, Australia. May. Property released.

Doug Gimesy / Portrait of a Mandrill male (Mandrillus sphinx). Captive, at Melbourne Zoo, Parkville, Victoria, Australia. May. Property released.

Doug Gimesy / Portrait of a Mandrill male (Mandrillus sphinx). Captive, at Melbourne Zoo, Parkville, Victoria, Australia. May. Property released.

Edwin Giesbers / Mandrills (Mandrillus sphinx) in their enriched outdoor enclosure, Ouwehands Zoo, Rhenen, The Netherlands. Captive.

Edwin Giesbers / Zoo sign about the Mandrill (Mandrillus sphinx) in front of the enclosure, Ouwehands Zoo, Rhenen, The Netherlands.

Edwin Giesbers / Zoo sign about Mandrills (Mandrillus sphinx) in front of the enclosure, Ouwehands Zoo, Rhenen, The Netherlands.

Enrique Lopez-Tapia / Park biologists place a hide to watch a troop of mandrills (Mandrillus sphinx). Lopé National Park, Ecosystem and Relict Cultural Landscape of Lopé-Okanda UNESCO World Heritage Site, Gabon.

Enrique Lopez-Tapia / Park biologists radio tracking a troop of Mandrills (Mandrillus sphinx) on the map. Lopé National Park, Ecosystem and Relict Cultural Landscape of Lopé-Okanda UNESCO World Heritage Site, Gabon.

Enrique Lopez-Tapia / Park biologists radio tracking a troop of Mandrills (Mandrillus sphinx) on the map. Lopé National Park, Ecosystem and Relict Cultural Landscape of Lopé-Okanda UNESCO World Heritage Site, Gabon.

Enrique Lopez-Tapia / Park biologists radio tracking a troop of Mandrills (Mandrillus sphinx) on the map. Lopé National Park, Ecosystem and Relict Cultural Landscape of Lopé-Okanda UNESCO World Heritage Site, Gabon.

Enrique Lopez-Tapia / Park biologists radio tracking a troop of Mandrills (Mandrillus sphinx) on the map. Lopé National Park, Ecosystem and Relict Cultural Landscape of Lopé-Okanda UNESCO World Heritage Site, Gabon.

Enrique Lopez-Tapia / Park biologists radio tracking a troop of Mandrills (Mandrillus sphinx) on the map. Lopé National Park, Ecosystem and Relict Cultural Landscape of Lopé-Okanda UNESCO World Heritage Site, Gabon.

Enrique Lopez-Tapia / Park biologists radio tracking a troop of Mandrills (Mandrillus sphinx) on the map. Lopé National Park, Ecosystem and Relict Cultural Landscape of Lopé-Okanda UNESCO World Heritage Site, Gabon.

Enrique Lopez-Tapia / Park biologiss radiotracking mandrills (Mandrillus sphinx). Lopé National Park, Ecosystem and Relict Cultural Landscape of Lopé-Okanda UNESCO World Heritage Site, Gabon.

Enrique Lopez-Tapia / Park biologists radio tracking a troop of Mandrills (Mandrillus sphinx) on the map. Lopé National Park, Ecosystem and Relict Cultural Landscape of Lopé-Okanda UNESCO World Heritage Site, Gabon.

Cyril Ruoso / Male Mandrill (Mandrillus sphinx) sitting on ground, yawning, Gabon.

Cyril Ruoso / Male Mandrill (Mandrillus sphinx) head portrait, Gabon.

Cyril Ruoso / Male Mandrill (Mandrillus sphinx) yawning, Gabon.

Cyril Ruoso / Male Mandrill (Mandrillus sphinx) yawning, Gabon.

Cyril Ruoso / Mandrill (Mandrillus sphinx) immature male, portrait, Gabon.

Cyril Ruoso / Male Mandrill (Mandrillus sphinx) portrait, Gabon.

Cyril Ruoso / Mandrill (Mandrillus sphinx) portrait, Gabon.

Cyril Ruoso / Male Mandrill (Mandrillus sphinx) sitting, Gabon.