Responses to quantity: perceptual versus cognitive mechanisms in chimpanzees (Pan troglodytes).

  title={Responses to quantity: perceptual versus cognitive mechanisms in chimpanzees (Pan troglodytes).},
  author={Sarah T. Boysen and Gary G. Berntson},
  journal={Journal of experimental psychology. Animal behavior processes},
  volume={21 1},
  • S. Boysen, G. Berntson
  • Published 1995
  • Medicine
  • Journal of experimental psychology. Animal behavior processes
Two chimpanzees were trained to select among 2 different amounts of candy (1-6 items). The task was designed so that selection of either array by the active (selector) chimpanzee resulted in that array being given to the passive (observer) animal, with the remaining (nonselected) array going to the selector. Neither animal was able to select consistently the smaller array, which would reap the larger reward. Rather, both animals preferentially selected the larger array, thereby receiving the… 
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  • M. Beran
  • Psychology, Medicine
    Journal of experimental psychology. Animal behavior processes
  • 2012
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