About 50-Million-Year-Old ‘Monkey Facebook’ Discovered! Biologists Say
U.S. biologists have discovered an "evolutionary Facebook" to explain why the faces of some primates contain many different colors while other primate faces are quite plain.
Researchers at UCLA have discovered that larger groups like Old World monkeys and apes that are more social have more complex facial features and coloration, whereas, species that have smaller group sizes tend to have simpler faces with fewer colors.
In the most recent findings, which appears in a recent issue of Nature, researchers studied faces of 139 Old World African and Asian primate species that have been diversifying over about 25 million years, which is based on a research conducted last year on the evolution of 129 primate faces in species from Central and South America.
They discovered that some species have many different facial colors-black, blue, red, orange and white-in various proportions and combinations and often-striking patterns while other primate faces are quite simple with few colors.
Presence of more color patches in the face makes is what makes the face appear complex and diverse across individuals within species. This diversity could help them distinguish between their friends and foes, which may be a more difficult task in larger groups, say researchers.
Interestingly, the species that live in the same niche with other closely related species exhibit complex faces. Such facial complexity could help in species recognition, researchers discover.
Michael Alfaro, an associate professor of ecology and evolutionary biology, and senior author of the study said:
"Humans are crazy for Facebook, but our research suggests that primates have been relying on the face to tell friends from competitors for the last 50 million years and those social pressures have guided the evolution of the enormous diversity of faces we see across the group today."
"Faces are really important to how monkeys and apes can tell one another apart. We think the color patterns have to do both with the importance of telling individuals of your own species apart from closely related species and for social communication among members of the same species."
The majority of Old World monkeys and apes are social.
Jessica Lynch Alfaro, an adjunct assistant professor in the UCLA Department of Anthropology and UCLA's Institute for Society and Genetics, and coauthor of the study said:
Some species, like the mandrills, can live in groups with up to 800 members. At the other end of this spectrum are orangutans. In most orangutan populations, adult males often travel and sleep alone and sleep alone, and only their young accompany females.
Some primates like the hamadryas baboons, have hierarchal societies with harems, clans, bands and troops. Others, like chimpanzees, break up into small sub-groups and come together rarely in very large communities.
Source: Science Daily