Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus), three climbing tree. Northern Colombia.

Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus), adult with two week old baby on back. Northern Colombia.

Edwin Giesbers / Golden lion tamarin (Leontopithecus rosalia) captive, occurs in the Atlantic Rainforest of Brazil. Critically endangered.

Dave Watts / Golden lion tamarin (Leontopithecus rosalia rosalia) captive in zoo. Occurs in Brazil.

Juan Carlos Munoz / Golden-headed lion tamarin (Leontopithecus chrysomelas) captive portrait, Apenheul Park, Netherlands.

Luiz Claudio Marigo / Wied's black tufted-ear marmoset (Callithrix kuhli) clinging to branch in mountainous Atlantic Rainforest of Serra Bonita Natural Private Heritage Reserve (RPPN Serra Bonita), municipality of Camacan,...

Claus Meyer / Pygmy Marmoset (Cebuella pygmaea) endangered, pair, world's smallest primate, Amazon, Brazil

Oscar Dewhurst / Saddle-back Tamarin (Saguinus fuscicollis), feeding on a katydid in a rainforest clearing. Madre de Dios, Peru. March

Oscar Dewhurst / Emperor Tamarin (Saguinus imperator) in a rainforest clearing. The animal is one of many being studied, hence the metal band hanging from its neck. Madre de Dios, Peru. March. Cropped

Oscar Dewhurst / Saddleback tamarin (Saguinus fuscicollis) on tree tunk. Madre de Dios, Peru. March