Bernard Castelein / Guianan brown capuchin (Sapajus apella) chewing on branch, Pampas del Yacuma Protected Area, Bolivia

Alex Hyde / Brown / Tufted Capuchin (Cebus apella) family group in cloud forest, Manu Biosphere Reserve, Peru.

Mark Bowler / Black capuchin, (Sapajus nigritus) female standing on hind legs, Rio de Janeiro, Brazil.

Ben Cranke / Black-striped capuchin (Sapajus libidinosus) using rock as a tool to break open palm nut, Parnaiba Headwaters National Park, Piaui, Brazil. August.

Ben Cranke / Black-striped capuchin (Sapajus libidinosus) using rock as a tool to break open palm nut Parnaiba Headwaters National Park, Piaui, Brazil. July.

Ben Cranke / Black-striped capuchin (Sapajus libidinosus) using rock as a tool to break open palm nut, Parnaiba Headwaters National Park, Piaui, Brazil. July.

Ammonite / Male White-throated / White-faced capuchin (Cebus capucinus) climbing and jumping in canopy, showing use of prehensile tail, Santa Rosa National Park, Costa Rica.

Ammonite / White-throated capuchins (Cebus capucinus) alarm calling, Santa Rosa National Park, Costa Rica.

Ammonite / White-throated / White-faced capuchin (Cebus capucinus) climbing and playing with twig, showing use of prehensile tail, Santa Rosa National Park, Costa Rica.

Ammonite / Family of White-throated / White-faced capuchins (Cebus capucinus) resting and grooming each other, Santa Rosa National Park, Costa Rica.

Suzi Eszterhas / White-faced Capuchin (Cebus capucinus imitator) mother and baby. Osa Peninsula, Costa Rica

Mary McDonald / Black striped capuchin (Sapajus libidinosus) using rocks to crack nuts, Piaui, Brazil