Abstract # 54:

Scheduled for Saturday, September 17, 2011 03:30 PM-03:45 PM: Session 11 (Meeting Room 408)


K. D. Hughes and L. R. Santos
Yale University, Department of Anthropology, 10 Sachem St, New Haven, CT 06510, USA

Primates constantly solve small-scale spatial problems, tracking nearby objects and agents as they move and disappear. One way to investigate how primates solve these problems is with the rotational displacement task. The task involves tracking an object at a hiding location while the supporting substrate rotates and can be solved either through visual tracking of the rotation or through association of a hidden object with a landmark. Investigation across several primate taxa has revealed that humans may be unique in using landmarks, perhaps due to language and enculturation. This makes the strong prediction that no nonhuman primates use landmarks in navigating small spaces. We expanded this investigation by testing how two monkey species— rhesus macaques (Macaca mulatta) and brown capuchins (Cebus apella)— solve this task. In our rotational displacement task, we designed conditions in which we varied the presence and absence of landmarks/features and visual access to the array during the rotation. Macaques solved the task only when they had both featural information and visual access to the rotation. In contrast, capuchins did not initially seem sensitive to landmark/featural information, however, after many trials, their use of the most obvious landmarks significantly improved. A preference to use landmarks/features may be a human trait, but some primates use these cues to a degree, and the ability to utilize this information varies among primate taxa.