Lucas Bustamante / Toque Macaques (Macaca sinica) Polonnaruwa, Central Province, Sri Lanka

Ernie Janes / Celebes crested macaque (Macaca nigra) infant, captive.

John Shaw / Snow monkey or Japanese macaque (Macaca fuscata) female with baby clinging to her back. Jigokudani, Japan, February.

Bernard Castelein / Rhesus macaque (Macaca mulatta), mixed group of female and juveniles, walking along a track, Keoladeo National Park, Bharatpur, India

Bernard Castelein / Rhesus macaque (Macaca mulatta), juveniles playing in tree, Keoladeo NP, Bharatpur, India

Jed Weingarten / Wild Wonders of China / Tibetan macaque (Macaca thibetana) carrying young baby, Tangjiahe Nature Reserve, Sichuan Province, China

Magnus Lundgren / Wild Wonders of China / Tibetan macaque (Macaca thibetana) juvenile climbing in a tree in Tangjiahe Nature Reserve, Sichuan Province, China

Shane P. White / Japanese Macaque (Macaca fuscata) in hot spring, Jigokudani, Nagano, Japan

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

Cyril Ruoso / Long-tailed macaque (Macaca fascicularis) approaching camera, Koram island, Khao Sam Roi Yot National Park, Thailand.

Cyril Ruoso / Long-tailed macaque (Macaca fascicularis) head portrait, Koram island, Khao Sam Roi Yot National Park, Thailand.

Cyril Ruoso / Long-tailed macaque (Macaca fascicularis) grooming, Koram island Khao Sam Roi Yot National Park, Thailand.