Researchers have long believed that humans and great apes were the only animals capable of recognizing themselves in a mirror. But a new study from Emory's Yerkes National Primate Research Center indicates capuchin monkeys may see more than a stranger in their own reflections. Researchers Frans de Waal, Marietta Dindo, Cassiopeia A. Freeman, and Marisa J. Hall exposed eight adult female and six adult male brown capuchin monkeys to three conditions to determine their responses to: a familiar same-sex animal, an unfamiliar same-sex animal, and a mirror. Females showed more eye contact and friendly behavior and fewer signs of anxiety in front of the mirror than toward the unfamiliar animal. Males showed greater ambiguity, but still reacted differently to mirrors and strangers. These findings suggest the monkeys seem to recognize their mirror reflections as special and may not confuse them with an actual stranger. This research, reported in the current issue of the Proceedings of the National Academy of Sciences, may lead to further examination of self-awareness and an appraisal of two schools of thought about the concept of self.—P.P.P.


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