Chimpanzees and bonobos distinguish between risk and ambiguity.

Published

Journal Article

Although recent research has investigated animal decision-making under risk, little is known about how animals choose under conditions of ambiguity when they lack information about the available alternatives. Many models of choice behaviour assume that ambiguity does not impact decision-makers, but studies of humans suggest that people tend to be more averse to choosing ambiguous options than risky options with known probabilities. To illuminate the evolutionary roots of human economic behaviour, we examined whether our closest living relatives, chimpanzees (Pan troglodytes) and bonobos (Pan paniscus), share this bias against ambiguity. Apes chose between a certain option that reliably provided an intermediately preferred food type, and a variable option that could vary in the probability that it provided a highly preferred food type. To examine the impact of ambiguity on ape decision-making, we interspersed trials in which chimpanzees and bonobos had no knowledge about the probabilities. Both species avoided the ambiguous option compared with their choices for a risky option, indicating that ambiguity aversion is shared by humans, bonobos and chimpanzees.

Full Text

Duke Authors

Cited Authors

  • Rosati, AG; Hare, B

Published Date

  • February 2011

Published In

Volume / Issue

  • 7 / 1

Start / End Page

  • 15 - 18

PubMed ID

  • 21106573

Pubmed Central ID

  • 21106573

Electronic International Standard Serial Number (EISSN)

  • 1744-957X

International Standard Serial Number (ISSN)

  • 1744-9561

Digital Object Identifier (DOI)

  • 10.1098/rsbl.2010.0927

Language

  • eng