This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Objective: To recognize that lower primate species may possess self-awareness. PROGRESS: This research found that, under specific conditions, a rhesus macaque monkey that normally would fail a self-recognition "mark" test can still recognize itself in a mirror and perform actions that scientists would expect from animals that are self-aware. This finding may cause us to re-evaluate the relevance of the mark test and the existence of a definitive cognitive divide between higher and lower primates. We placed head implants on two rhesus macaque monkeys while preparing to study attention deficit disorder and sensorimotor integration. An experienced animal technician observed that one of the monkeys could recognize itself in a small mirror, in contrast to evidence from the scientific literature. In the standard mark test, which chimpanzees and people easily pass, a harmless mark is put on the animal's face, where it can only be seen in a mirror. If the animal stares at the mirror and touches the mark, it is said to be self-aware: It knows that the mirror shows its own reflection, not that of another animal. Animals that lack self-awareness may, for example, search for the "invading" animal behind the mirror, or adopt and aggressive or submissive response to the perceived intruder. Rhesus macaques, a mainstay of medical and psychological research, have long failed the mark test. But in our lab, the monkeys that got the implants were clearly looking in the mirror while examining and grooming their foreheads, near the implant. They were also examining areas on their body, particularly the genitals, that they had never seen before. In some cases, the monkeys even turned themselves upside down during these examinations. In other cases, they grasped and adjusted the mirror to get a better view of themselves. When we covered the mirror glass with black plastic, these behaviors disappeared, and the monkeys ignored what had been a subject of fascination. Scientists who have used the mark test to explore self-awareness have found the quality in one species of bird, in one individual elephant, and in dolphins and orangutans. And so instead of asking how self-awareness evolved only among primates, they face the larger question of how it evolved multiple times in distantly related species. This discovery may refine how the mark test is used, as we now clearly have data showing that rhesus macaques can recognize themselves in the mirror, even though the species fails the mark test. This research, while based in SMPH, involved the use of WNPRC Animal Services. News Item, Sept. 29, 2010: For first time, monkeys recognize themselves in the mirror, indicating self-awareness http://www.news.wisc.edu/18469 PUBLICATION: Abigail Z. Rajala, Katharine R. Reininger, Kimberly M. Lancaster, and Luis C. Populin. PLoS One. Rhesus Monkeys (Macaca mulatta) Do Recognize Themselves in the Mirror: Implications for the Evolution of Self-Recognition 2010;5(9): e12865. E-pub 2010 September 29. PMCID: PMC2947497
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