Face recognition in primates: a cross-species study.

Recognition for human faces, monkey faces, and objects was assessed in both adult humans (Homo sapiens) and monkeys (Macaca mulatta) with a visual paired-comparison task. The results demonstrated that while both species showed strong novelty preference for objects, human participants showed novelty preference for human faces but not for monkey faces, and vice versa for the monkeys. This `species-specific effect' in face recognition is discussed in relation with data on both the `other-race effect' observed in humans and the effects of experience or training on face recognition processes in primates.