Christophe Courteau / Red Uakari Monkey {Cacajao rubicundus} jumping from branch to branch. Mamiraua Wildlife Reserve. Amazonia, Brazil

Juan Manuel Borrero / White bald-headed uakari (Cacajao calvus) head portrait. Amazon basin. Iquitos. Loreto. Peru, Captive

Mark Bowler / Peruvian red uakari monkey (Cacajao calvus ucayalii) eating aguaje palm fruits (Mauritia flexuosa) Yavari River, Peru, vulnerable species, wild

David Tipling / Bald Uakari (Cacajao calvus ucayalii) Iquitos region, Amazon Basin, Peru. Controlled conditions.

Christophe Courteau / Red Uakari Monkey {Cacajao rubicundus} jumping from branch to branch. Mamiraua Wildlife Reserve. Amazonia, Brazil

Rod Williams / Red uakari monkey (Cacajao calvus rubicundus), female, Captive, occurs Amazon Basin, Brazil, Peru, South America, Endangered.

Mark Bowler / Peruvian red uakari monkey (Cacajao calvus ucayalii) adult male in hanging display. Yavari River, Peru, vulnerable species, wild

Mark Bowler / Peruvian red uakari monkey (Cacajao calvus ucayalii) eating aguaje palm fruits (Mauritia flexuosa) Yavari River, Peru, vulnerable species, wild

Mark Bowler / Peruvian red uakari monkey (Cacajao calvus ucayalii) in rainforest tree, Yavari River, Peru, wild, vulnerable species

Mark Bowler / Peruvian red uakari monkey (Cacajao calvus ucayalii) feeding in rainforest tree, Yavari River, Peru, vulnerable species, wild

Mark Bowler / Peruvian red uakari monkey (Cacajao calvus ucayalii) baby with fingers in mouth, captive, vulnerable species

Luiz Claudio Marigo / Male Red Uakari (Cacajao calvus rubicundus) resting in canopy of Amazon Rainforest, Amazonas State, Northern Brazil. Endangered