Abstract
Self-recognition has been explored in nonlinguistic organisms by recording whether individuals touch a dye-marked area on visually inaccessible parts of their face while looking in a mirror or inspect parts of their body while using the mirror's reflection. Only chimpanzees, gorillas, orangutans, and humans over the age of approximately 2 years consistently evidence self-directed mirror-guided behavior without experimenter training. To evaluate the inferred phylogenetic gap between hominoids and other animals, a modified dye-mark test was conducted with cotton-top tamarins (Saguinus oedipus), a New World monkey species. The white hair on the tamarins' head was color-dyed, thereby significantly altering a visually distinctive species-typical feature. Only individuals with dyed hair and prior mirror exposure touched their head while looking in the mirror. They looked longer in the mirror than controls, and some individuals used the mirror to observe visually inaccessible body parts. Prior failures to pass the mirror test may have been due to methodological problems, rather than to phylogenetic differences in the capacity for self-recognition. Specifically, an individual's sensitivity to experimentally modified parts of its body may depend crucially on the relative saliency of the modified part (e.g., face versus hair). Moreover, and in contrast to previous claims, we suggest that the mirror test may not be sufficient for assessing the concept of self or mental state attribution in nonlinguistic organisms.
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- ANDREW R. J. EVOLUTION OF FACIAL EXPRESSION. Science. 1963 Nov 22;142(3595):1034–1041. doi: 10.1126/science.142.3595.1034. [DOI] [PubMed] [Google Scholar]
- Epstein R., Lanza R. P., Skinner B. F. "Self-awareness" in the pigeon. Science. 1981 May 8;212(4495):695–696. doi: 10.1126/science.212.4495.695. [DOI] [PubMed] [Google Scholar]
- Gallop G. G., Jr Chimpanzees: self-recognition. Science. 1970 Jan 2;167(3914):86–87. doi: 10.1126/science.167.3914.86. [DOI] [PubMed] [Google Scholar]
- Gallup G. G., Jr, Suarez S. D. Social responding to mirrors in rhesus monkeys (Macaca mulatta): effects of temporary mirror removal. J Comp Psychol. 1991 Dec;105(4):376–379. doi: 10.1037/0735-7036.105.4.376. [DOI] [PubMed] [Google Scholar]
- Povinelli D. J., Parks K. A., Novak M. A. Do rhesus monkeys (Macaca mulatta) attribute knowledge and ignorance to others? J Comp Psychol. 1991 Dec;105(4):318–325. doi: 10.1037/0735-7036.105.4.318. [DOI] [PubMed] [Google Scholar]
- Povinelli D. J. Reconstructing the evolution of mind. Am Psychol. 1993 May;48(5):493–509. doi: 10.1037//0003-066x.48.5.493. [DOI] [PubMed] [Google Scholar]