Magnus Lundgren / Wild Wonders of China / Central Yunnan black crested gibbon (Nomascus concolor jingdongensis), mother and baby hanging in canopy. Wuliangshan Nature Reserve, Jingdong, Yunnan Province, China.

Staffan Widstrand / Wild Wonders of China / Eastern hoolock gibbon (Hoolock leuconedys) hanging from a branch in its arms, resting between forays through the rainforest, Gaoligongshan Nature reserve, Yunnan, China

Thomas Marent / Agile Gibbon (Hylobates agilis) pair, Camp Leaky, Tanjung Puting National Park, Indonesia

Magnus Lundgren / Wild Wonders of China / Central Yunnan black crested gibbon (Nomascus concolor jingdongensis), mother and baby swinging in canopy. Wuliangshan Nature Reserve, Jingdong, Yunnan Province, China.

Enrique Lopez-Tapia / Agile gibbon (Hylobates agilis) collecting bananas from a Camp Leakey orangutan feeding platform, Tanjung Puting National Park, Kalimantan, Borneo, Indonesia, October.

Enrique Lopez-Tapia / Agile gibbon (Hylobates agilis) carrying bananas collected from a feeding platform climbing up a tree, Tanjung Puting National Park, Kalimantan, Borneo, Indonesia, October.

Suzi Eszterhas / Agile gibbon (Hylobates agilis) in tree, Tanjung Puting National Park, Indonesia.

Suzi Eszterhas / Agile gibbon (Hylobates agilis) in tree, Tanjung Puting National Park, Indonesia.

Dong Lei / Hoolock gibbon (Hoolock leuconedys) climbing tree, Gaoligong Mountain National Nature Reserve, Tengchong county, Yunnan Province, China.

Inaki Relanzon / Agile Gibbon (Hylobates agilis) in Tanjung Puting National Park, Borneo-Kalimatan, Indonesia.

Mark Taylor / Bornean white-bearded or agile gibbon, (Hylobates albibarbis) in tree, south west Borneo.

Nick Garbutt / Agile Gibbon (Hylobates agilis) resting in forest canopy, Tanjung Puting National Park, Kalimantan, Borneo.