CRAIG K. LORENZ / SCIENCE PHOTO LIBRARY CRAIG K. LORENZ / SCIENCE PHOTO LIBRARY
The Colombian Black-faced Spider Monkey (Ateles fusciceps robustus) lives in the mature rainforests of Colombia. The group size of the monkeys varies from 4 to 5 to over 100 depending on the time of year and the amount of food available. This is an adaptation to swinging through the trees, thumbs being unnecessary for this kind of movement. World Wildlife Zoo, Phoeniz, Arizona.
Model release not required. Property release not required.