Cyril Ruoso / Long-tailed Macaque (Macaca fascicularis) troop, Khao Sam Roi Yot National Park, Thailand

Tony Phelps / Chacma baboon (Papio ursinus) troop exiting den, DeHoop Nature Reserve, Western Cape, South Africa, June.

Konrad Wothe / Showreel of Male Chimpanzees (Pan troglodytes) attacking the alpha male of their troop, Mahale Mountains National Park, Tanzania.

Ingo Arndt / Gelada baboon males fighting, Simien Mt NP, Ethiopia {Theropithecus gelada}

Ingo Arndt / Gelada baboon troop on rock {Theropithecus gelada} Simien Mt NP, Ethiopia

Konrad Wothe / Male Chimpanzees (Pan troglodytes) attacking the alpha male of their troop, Mahale Mountains National Park, Tanzania.

Jabruson / Mozambican children with captive Yellow Baboon youngster (Papio cynocephalus) young animal caught during troop crop raiding. Pemba to Montepuez highway, north-eastern Mozambique, November 2011. Specia...

Jabruson Motion / Silverback Western gorilla (Gorilla gorilla) 'Makumba', leader of the 'Makumba' troop, breaking into a termite's nest in order to feed, Bai Hokou, Dzanga-Ndoki National Park, Central African Republic

Jabruson Motion / Silverback Western gorilla (Gorilla gorilla) 'Makumba', leader of the 'Makumba' troop, breaking into a termite's nest in order to feed, Bai Hokou, Dzanga-Ndoki National Park, Central African Republic

Thomas Marent / Golden Snub-nosed Monkey (Rhinopithecus roxellana) troop, Qinling Mountains, Shaanxi, China

Cyril Ruoso / Ring-tailed Lemur (Lemur catta) troop walking down dirt road, vulnerable, Berenty Private Reserve, Madagascar

Juan Carlos Munoz / Gelada baboon (Theropithecus gelada) troop, Simien Mountains, Ethiopia, Africa