Abstract # 38:

Scheduled for Saturday, September 13, 2014 04:15 PM-04:30 PM: Session 10 (Henry Oliver) Oral Presentation


K. Sayers and C. R. Menzel
Georgia State University, Language Research Center, Decatur, GA 30034, USA
     Nonhuman memory has frequently been examined in the context of the what, where, and when of an event. This likely underestimates the complexity of memory, which could involve multiple what, where, and when components, and well as a plethora of other information. We investigate memory for complex events with three chimpanzees (Pan troglodytes), two of them lexigram-proficient, at the Language Research Center. While the apes observed, various foods were hidden in unique locations in a wooded test area. On any given trial, the hidden items varied by type, distance from chimpanzee, quantity, and/or perishability over time. In certain variations, some items decreased in value over time, or increased in value over time. In another variation, a subset of the foods increased in value while another subset simultaneously decreased in value. The chimpanzees were allowed to recover the items after delays ranging from 5 minutes to greater than 24 hours. It was found that the chimpanzees could weigh multiple variables concurrently, including, in some cases, information about time elapsed since cue-giving, to approximate an optimal recovery sequence. These results suggest a rich memory base, and are discussed in relation to the selective advantage such abilities would offer primates foraging in the wild. Supported by the Leakey Foundation, Wenner-Gren Foundation, R01 HD-056352, 1F32HD061177, and P01 HD-060563.