In a written exchange, associate professor Michael Alfaro and postdoctoral scientist Sharlene E. Santana described their investigation with American Scientistsenior editor Catherine Clabby.
Catherine Clabby in American Scientist:
What inspired your research into primate faces?
When you see the faces of primates, you see an extraordinary diversity of shapes, colors and patterns, so we wondered what were the factors behind this diversity. Social behaviors seemed to be a very likely candidate underlying the diversity of primate faces, so that drew us in to further explore how behaviors can shape the evolution of anatomy in these mammals. Neotropical primates were ideal to start our studies of facial diversity because they are a single evolutionary radiation spanning a wide variety of habitats and social systems, and they have an extraordinary variation in their facial features.
Are the faces of primates really that different from the faces of other mammals?
What is particular about primates is their high reliance on facial cues to interact socially, more so than many other mammals. Primates use characteristics of their faces and facial expressions to recognize individuals in their groups and to assess each other’s behaviors. Related to this, primates have evolved a very well-developed visual system and neural centers for facial recognition. Such an important role in communication has shaped the evolution of primate faces, along with ecological and physiological functions.