International Journal of Comparative Psychology

Mirror self-recognition (MSR) has been studied in many species of primates, but not previously in the black-and-white colobus monkey ( Colobus guereza ). A family group of five monkeys was videotaped in a baseline session with clear glass panel and nine sessions (270 min) with a mirror. All monkeys showed substantial interaction with the mirror. The monkeys show evidence of limited use of the mirror’s reflective properties, but no evidence of behaviors indicating MSR. These data are consistent with the failure of other species of monkeys to show MSR and with the hypothesis that great apes are the only species capable of MSR.