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  • Influence
Chimpanzees are indifferent to the welfare of unrelated group members
Experimental tests of the existence of other-regarding preferences in non-human primates are presented and it is shown that chimpanzees (Pan troglodytes) do not take advantage of opportunities to deliver benefits to familiar individuals at no material cost to themselves, suggesting that chimpanzee behaviour is not motivated by other- Regarding preferences.
Chimpanzee minds: suspiciously human?
We don't need a microscope to explore the chimpanzee's mind
It is called for recognition of this problem, and a shift from experimental paradigms that cannot resolve this question, to ones that might allow researchers to intelligently determine when it is necessary to postulate the presence of a system which reasons about both behavior and mental states.
Gorilla (Gorilla gorilla gorilla) and orangutan (Pongo abelii) understanding of first- and second-order relations
  • J. Vonk
  • Psychology
    Animal Cognition
  • 1 March 2003
Four orangutans and one gorilla matched images in a delayed matching-to-sample (DMTS) task based on the relationship between items depicted in those images, thus demonstrating understanding of both
Do chimpanzees learn reputation by observation? Evidence from direct and indirect experience with generous and selfish strangers
Chimpanzees can infer the reputation of strangers by eavesdropping on third-party interactions by significantly preferring to beg from the novel generous donors on the first opportunity to do so.