Color and pattern complexity in the faces of New World primates align with their social needs, according to research by University of California, Los Angeles, biologists. Those who live isolated from their kind have more distinctive facial color and markings. Those who live with more of their own tend to have plain faces, which could make facial expressions stand out more. In this diagram, warmer colors indicate greater complexity in facial color patterns. Illustrations of species here include drawings of (1) Cacajao calvus, (2) Callicebus hoffmansi, (3) Ateles belzebuth, (4) Alouatta caraya, (5) Aotus trivirgatus, (6) Cebus nigritus, (7) Saimiri boliviensis, (8) Leontopithecus rosalia, (9) Callithrix kuhli, (10) Saguinus martinsi and (11) Saguinus imperator.
Excerpt of an article written by Catherine Clabby, at American Scientist. Continue HERE. Illustrations by Stephen Nash. Figure courtesy of the Proceedings of the Royal Society B.