Anup Shah / Western lowland gorilla (Gorilla gorilla gorilla) sub-adult female 'Mosoko' aged 8 years crossing a river, Bai Hokou, Dzanga Sangha Special Dense Forest Reserve, Central African Republic

Andy Rouse / Mountain gorilla (Gorilla beringei) silverback in Susa group, Parc National des Volcans, Rwanda

Andy Rouse / Mountain gorilla (Gorilla beringei beringei) silverback male portrait, Volcanoes NP, Virunga Mountains, Rwanda

Eric Baccega / Mountain gorilla (Gorilla beringei beringei) juvenile female stretching hand out towards camera, member of the Kabirizi group, Virunga National Park, North Kivu, Democratic Republic of Congo, Africa,...

Luis Quinta / Beach at the north of Principe Island, Democratic Republic of Sao Tome and Principe, Gulf of Guinea.

Jabruson Motion / Male Western gorilla (Gorilla gorilla) displaying, throws clump of grass into the air, runs through bai and hits other gorilla, Maya Nord Bai, Odzala-Kokoua National Park, Cuvette-Ouest Region, Republ...

Jabruson Motion / National park guards and trackers transporting a dead silverback Mountain gorilla (Gorilla beringei beringei), Bukima, Virunga National Park, Democratic Republic of Congo, 1996.

Jabruson Motion / Three juvenile Mountain gorillas (Gorilla beringei beringei) resting in vegetation, rolling and playing before approaching camera, Bukima, Virunga National Park, Democratic Republic of Congo, 1996.

Jabruson Motion / Close-up of a male Mountain gorilla (Gorilla beringei beringei) looking at camera, pulls off lens component, Bukima, Virunga National Park, Democratic Republic of Congo, 1996.

Jabruson Motion / Close-up of a female Mountain gorilla (Gorilla beringei beringei) feeding, gets up and rolls into new resting position near other family members, Bukima, Virunga National Park, Democratic Republic of...

Jabruson Motion / Female Mountain gorilla (Gorilla beringei beringei) getting up from resting and eating, twirls around before settling down into a new resting position, Bukima, Virunga National Park, Democratic Republ...

Jabruson Motion / Silverback Mountain gorilla (Gorilla beringei beringei) and family resting in vegetation, with a juvenile peering into the camera lens Bukima, Virunga National Park, Democratic Republic of Congo, 1996...

Jabruson Motion / Close-up of a male Mountain gorilla (Gorilla beringei beringei) and juvenile resting, captivated by reflection in camera lens, knocks juvenile over, Bukima, Virunga National Park, Democratic Republic...

Jabruson Motion / Close-up of a female Mountain gorilla (Gorilla beringei beringei) looking at camera, scratches face, Bukima, Virunga National Park, Democratic Republic of Congo, 1996.

Jabruson Motion / Close-up of a male Mountain gorilla (Gorilla beringei beringei) looking at camera, with another male approaching from behind, beats chest displaying, Bukima, Virunga National Park, Democratic Republic...

Jabruson Motion / Wide angle shot of a juvenile Mountain gorilla (Gorilla beringei beringei) swinging from a branch and looking at camera, with a silverback nearby, Bukima, Virunga National Park, Democratic Republic of...

Jabruson Motion / Close-up of a tracker, shot pans to a silverback Mountain gorilla (Gorilla beringei beringei) looking at camera, Bukima, Virunga National Park, Democratic Republic of Congo, 1996.

Eric Baccega / View of the lava lake in Nyiragongo volcano at night, Virunga National Park, Democratic Republic of Congo.

Neil Aldridge / Martial eagle (Polemaetus bellicosus) preening itself after a summer rainstorm in the central district, Kruger National Park. South Africa. Vulnerable species.

Cyril Ruoso / Tropical frog (Hyperolius sp) trying to climb onto leaf, Bateke Plateau NP, Gabon.

Fiona Rogers / Mountain gorilla (Gorilla gorilla beringei) female portrait, member of 'Humba' group . Virunga National Park, Democratic Republic of Congo, March.

Fiona Rogers / Mountain gorilla (Gorilla gorilla beringei) female portrait , part of the 'Munyanga' group. Virunga National Park, Democratic Republic of Congo, March.

Fiona Rogers / Mountain gorilla (Gorilla gorilla beringei) silverback male feet, member of 'Humba' group. Virunga National Park, Democratic Republic of Congo, March.

Fiona Rogers / Mountain gorilla (Gorilla gorilla beringei) infant portrait, member of 'Humba' group. Virunga National Park, Democratic Republic of Congo, March.

Fiona Rogers / Mountain gorilla (Gorilla gorilla beringei) female portrait, member of 'Humba' group . Virunga National Park, Democratic Republic of Congo, March.

Anup Shah / Mountain gorilla (Gorilla gorilla beringei) infant portrait, member of 'Humba' group. Virunga National Park, Democratic Republic of Congo, March.

Jabruson Motion / Silverback Eastern lowland gorilla (Gorilla beringei graueri) 'Chimanuka' getting up to reach for a Myrianthus holstii fruit, nearby juvenile takes a leaf from his rear, Kahuzi-Biega National Park, So...

Jabruson Motion / Silverback Western lowland gorilla (Gorilla gorilla gorilla) feeding on grass in forest bai, Odzala-Kokoua National Park, Cuvette-Ouest, Republic of Congo.

Jabruson Motion / Silverback Western lowland gorilla (Gorilla gorilla gorilla) leaving bai for forest with female and infant, crossing river bipedally, Odzala-Kokoua National Park, Cuvette-Ouest, Republic of Congo.

Jabruson Motion / Close up of a female Western lowland gorilla (Gorilla gorilla gorilla) female feeding on grasses in bai, Odzala-Kokoua National Park, Cuvette-Ouest, Republic of Congo.

Jabruson Motion / Close-up of a blackback Western lowland gorilla (Gorilla gorilla gorilla) feeding, Odzala-Kokoua National Park, Cuvette-Ouest, Republic of Congo.

Jabruson Motion / Female Western lowland gorilla (Gorilla gorilla gorilla) with very young infant, interacts with another gorilla, Odzala-Kokoua National Park, Cuvette-Ouest, Republic of Congo.

Jabruson Motion / Female Western lowland gorilla (Gorilla gorilla gorilla) feeding with blackback in forest bai, Odzala-Kokoua National Park, Cuvette-Ouest, Republic of Congo.

Christophe Courteau / Steam rising from the crater of Nyiragongo Volcano. Virunga National Park, North Kivu Province, Democratic Republic of Congo. September 2015.

Christophe Courteau / Lava Lake at night in the crater of Nyiragongo Volcano, Virunga National Park, North Kivu Province, Democratic Republic of Congo. September 2015.

Christophe Courteau / Lava Lake at night in the crater of Nyiragongo Volcano, Virunga National Park, North Kivu Province, Democratic Republic of Congo. September 2015.

Edwin Giesbers / Western lowland gorilla (Gorilla gorilla gorilla) baby resting on mother's back, captive, occurs in Central Africa. Critically endangered.

Edwin Giesbers / Western lowland gorilla (Gorilla gorilla gorilla) twin babies age 45 days, resting on mother's chest, captive, occurs in Central Africa. Critically endangered.

Edwin Giesbers / Western lowland gorilla (Gorilla gorilla gorilla) twin babies age 45 days resting on mother's chest, one suckling. captive, occurs in Central Africa. Critically endangered.

Edwin Giesbers / Western lowland gorilla (Gorilla gorilla gorilla) twin babies age 45 days sleeping in mother's arms, captive, occurs in Central Africa. Critically endangered.

Edwin Giesbers / Western lowland gorilla (Gorilla gorilla gorilla) twin babies age 45 days sleeping on mother's chest, captive, occurs in Central Africa. Critically endangered.

Edwin Giesbers / Western lowland gorilla (Gorilla gorilla gorilla) twin babies age 45 days resting side by side in mother's arms, captive, occurs in Central Africa. Critically endangered.

Edwin Giesbers / Western lowland gorilla (Gorilla gorilla gorilla) baby riding on mother's back, captive, occurs in Central Africa. Critically endangered.

Tony Heald / African lion (Panthera leo) three subadults resting on the road, one snarling, Central Kalahari Game Reserve, Botswana

Jabruson / Mummified infant Chimpanzee (Pan troglodytes) a relic from research from 1959, amongst old laboratory paraphernalia and assorted zoological specimens. CRSN (Centre de Recherche en Sciences Naturelles...

Jabruson Motion / Close up portrait of a female Mountain gorilla (Gorilla beringei beringei) seen through foliage, with an infant appearing and looking at the camera, Bukima, Virunga National Park, North Kivu, Democrat...

Jabruson Motion / Close up of a baby Mountain gorilla (Gorilla beringei beringei) looking at the camera before leaving the frame, part of the À™NyakamweÓ family group, Bukima, Virunga National Park, North Kivu, Democ...

Jabruson Motion / Silverback Mountain gorilla (Gorilla beringei beringei) from the 'Nyakamwe' family group looking at the camera before sitting back, Bukima, Virunga National Park, North Kivu, Democratic Republic of Co...