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Complexity Digest 2009.01 - 02.01
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04-Jan-2009

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Calculated Reciprocity After All: Computation Behind Token Transfers In
Orang-Utans, Biol. Lett.
 









Excerpt: Transfers and services are frequent in the animal kingdom. However,
there is no clear evidence in animals that such transactions are based on
weighing costs and benefits when giving or returning favours and keeping track
of them over time (i.e. calculated reciprocity). We tested two orang-utans
(Pongo pygmaeus abelii) in a token-exchange paradigm, in which each individual
could exchange a token for food with the experimenter but only after first
obtaining the token from the other orang-utan. Each orang-utan possessed tokens
valuable to their partner but useless to themselves. Both orang-utans actively
transferred numerous tokens (mostly partner-valuable) to their partner. (...)
Source: Calculated Reciprocity After All: Computation Behind Token Transfers In
Orang-Utans[
http://journals.royalsociety.org/content/qv2203362277hn50/?p=ce6811493139400f8b96988c84e7afab&pi=1
], V. Dufour, M. Pelé, M. Neumann, B. Thierry, J. Call, DOI:
10.1098/rsbl.2008.0644, Biological Letters, 2008/12/23
Contributed by Pritha Das - prithadas01yahoo.com

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