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.

Pete Oxford / Brown Capuchin (Cebus apella) using a rock to crack open a Piassava Palm (Attalea funifera) nut, Cerrado habitat, Piaui State, Brazil

Pete Oxford / Brown Capuchin (Cebus apella) using a rock to crack open a Piassava Palm (Attalea funifera) nut, Cerrado habitat, Piaui State, Brazil

Pete Oxford / Brown Capuchin (Cebus apella) in tree drinking from Piassava Palm (Attalea funifera) nut, monkeys use rocks and anvils to crack open nuts, Cerrado habitat, Piaui State, Brazil

Pete Oxford / Brown Capuchin (Cebus apella) stabilizes itself with its prehensile tail while using a heavy rock hammer to crack open palm nuts placed in small pits in the anvil rock surface, Cerrado habitat, Brazil

Pete Oxford / Brown Capuchin (Cebus apella) stabilizes itself with its prehensile tail while using a heavy rock hammer to crack open palm nuts placed in small pits in the anvil rock surface, Cerrado habitat, Brazil

Suzi Eszterhas / Brown capuchin monkey (Sapajus apella). Pantanal, Brazil.

Gabriel Rojo / Brown striped tufted capuchin monkey (Sapajus apella). Pantanal, Mato Grosso Brazil.

Gabriel Rojo / Brown striped tufted capuchin monkey (Sapajus apella) resting in tree. Amazon rainforest, Mato Grosso Brazil.

Bernard Castelein / Guianan brown capuchin, (Sapajus apella), walking up branch, Municipal protected area of Pampas del Yacuma, Bolivia

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

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

Bernard Castelein / Guianan brown capuchin (Sapajus apella), Madidi NP, Bolivia

Bernard Castelein / Guianan brown capuchin (Sapajus apella) feeding,, Madidi NP, Bolivia

Bernard Castelein / Guianan brown capuchin (Sapajus apella) feeding, Madidi NP, Bolivia

Bernard Castelein / Guianan brown capuchin (Sapajus apella), exploring a hole in a palm tree for insects, Madidi NP, Bolivia

Bernard Castelein / Guianan brown capuchin (Sapajus apella), exploring a hole in a palm tree for insects, Madidi NP, Bolivia

Bernard Castelein / Guianan Brown capuchin monkey (Sapajus apella) feeding, Madidi NP, Bolivia

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

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

Nick Garbutt / RF - Male tufted / Brown capuchin (Cebus apella) sitting in tree, mid-altitude montane forest, Manu Biosphere Reserve, Peru. (This image may be licensed either as rights managed or royalty free.)

Nick Garbutt / Tufted / Brown capuchin (Cebus apella), male sitting on branch in mid-altitude montane forest, Manu Biosphere Reserve, Peru.

Nick Garbutt / Tufted / Brown capuchin (Cebus apella), female and two juveniles sitting in branch, mid-altitude montane forest, Manu Biosphere Reserve, Peru.

Nick Garbutt / Tufted / Brown capuchin (Cebus apella), male standing in tree, mid-altitude montane forest, Manu Biosphere Reserve, Peru..

Nick Garbutt / Tufted / Brown capuchin (Cebus apella), female with baby on back, sitting in tree, mid-altitude montane forest, Manu Biosphere Reserve, Peru.

Angelo Gandolfi / Brown Capuchins (Cebus apella) running along the ground, Pantanal, Brazil

David Pattyn / Brown capped capuchin (Cebus apella) in tree, Pantanal, Mato Grosso, Brazil

Mark Bowler / Brown capuchin / Guianan Island Brown Capuchin (Cebus apella apella) feeding on fruit, Guiana. Captive

Mark Bowler / Brown capuchin / Guianan Island Brown Capuchin (Cebus apella apella) feeding on fruit, Guiana, captive

Roy Mangersnes / Brown-capped Capuchin (Sapajus / Cebus apella) in tree. Madidi National Park, Bolivia.

Roy Mangersnes / Brown-capped Capuchin (Sapajus / Cebus apella) in tree. Madidi National Park, Bolivia.

Roy Mangersnes / Brown-capped Capuchin (Sapajus / Cebus apella) peering at photographer from tree. Madidi National Park, Bolivia.

Roy Mangersnes / Brown-capped Capuchin (Sapajus / Cebus apella) on vines. Madidi National Park, Bolivia.

Roy Mangersnes / Brown-capped Capuchin (Sapajus / Cebus apella) looking up through canopy. Madidi National Park, Bolivia.

Roy Mangersnes / Brown-capped Capuchin (Sapajus / Cebus apella) on vines. Madidi National Park, Bolivia.

Luiz Claudio Marigo / Capuchin monkey (Cebus apella libidinosus) Serra da Capivara National Park, municipality of Sao Raimundo Nonato, Piaua­ State, northeastern Brazil. July

Piper Mackay / Brown capuchin monkey (Cebus apella) sitting on a branch, Pantanal Brazil.

Piper Mackay / Brown capped capuchin (Cebus apella) feeding on a banana, Pantanal, Brazil.

Juan Manuel Borrero / Brown-capped Capuchin (Cebus apella) climbing tree, Peru

Christophe Courteau / Brown capped capuchin (Cebus apella) looking menacing. Forest Is, Pantanal, Brazil.

Pete Oxford / Brown capuchin monkey (Cebus apella) Serra da Bodoquena, Mato Grosso do Sur Province. Brazil.

Luiz Claudio Marigo / Brown capped capuchin monkey {Cebus apella} Amazonas, Brazil

Pete Oxford / Brown capped capuchin monkey in tree {Cebus apella} Cerrado, Brazil

Pete Oxford / Brown capped capuchin monkey resting in tree {Cebus apella} Cerrado, Brazil

Pete Oxford / Brown capped capuchin monkey {Cebus apella} Cerrado, Brazil

Pete Oxford / Brown capped capuchin monkey standing {Cebus apella} Cerrado, Brazil

Anup Shah / Brown capped capuchin monkey carrying young on back {Cebus apella} Captive