ABSTRACT
Reports from a number of laboratories replicated Gallup’s (1970) findings with chimpanzees, and continued to fail to find evidence for mirror self-recognition in
lesser apes and a wide array of other nonhuman primates (review by Anderson & Gallup, 1999). Other research extended the presence of the capacity for mirror self-recognition to another great ape species, orangutans, but somewhat surprisingly, not gorillas (e.g., Suarez & Gallup, 1981). More recently, the final species of great ape, bonobos (Pan paniscus) has been tested and reported to exhibit evidence for mirror self-recognition, as well (although these latter tests have lacked important controls; Hyatt & Hopkins, 1994; Walraven, Elsacker, & Verheyen, 1995).
