Animal Cognition

, Volume 17, Issue 3, pp 657–669 | Cite as

Can orangutans (Pongo abelii) infer tool functionality?

  • Nicholas J. MulcahyEmail author
  • Michèle N. Schubiger
Original Paper


It is debatable whether apes can reason about the unobservable properties of tools. We tested orangutans for this ability with a range of tool tasks that they could solve by using observational cues to infer tool functionality. In experiment 1, subjects successfully chose an unbroken tool over a broken one when each tool’s middle section was hidden. This prevented seeing which tool was functional but it could be inferred by noting the tools’ visible ends that were either disjointed (broken tool) or aligned (unbroken tool). We investigated whether success in experiment 1 was best explained by inferential reasoning or by having a preference per se for a hidden tool with an aligned configuration. We conducted a similar task to experiment 1 and included a functional bent tool that could be arranged to have the same disjointed configuration as the broken tool. The results suggested that subjects had a preference per se for the aligned tool by choosing it regardless of whether it was paired with the broken tool or the functional bent tool. However, further experiments with the bent tool task suggested this preference was a result of additional demands of having to attend to and remember the properties of the tools from the beginning of the task. In our last experiment, we removed these task demands and found evidence that subjects could infer the functionality of a broken tool and an unbroken tool that both looked identical at the time of choice.


Orangutans Tools Inferential reasoning Physical cognition Connectivity 



A University of Queensland Fellowship awarded to N.J.M. funded the work. The research was approved by the University of Queensland’s Native/Exotic Wildlife and Marine Animals Committee and was conducted in accordance with all animal welfare laws of Australia. We thank the Singapore Zoo staff for help and advice during the study, in particular Sam Alagappasamy, John Sha Chi Munn, and all the orangutan keepers, especially Jackson Raj and Kumaran Sesshe.

Supplementary material

Supplementary material 1 (MOV 37758 kb)

Supplementary material 2 (MOV 42646 kb)


  1. Bania AE, Harris S, Kinsley HR, Boysen ST (2009) Constructive and deconstructive tool modification by chimpanzees (Pan troglodytes). Anim Cogn 12:85–95PubMedCrossRefGoogle Scholar
  2. Bentley-Condit VK, Smith EO (2010) Animal tool use: current definitions and an updated comprehensive catalog. Behavior 147:185–221CrossRefGoogle Scholar
  3. Call J (2007) Apes know that hidden objects can affect the orientation of other objects. Cognition 105:1–25PubMedCrossRefGoogle Scholar
  4. Call J (2010) Do apes know that they could be wrong? Anim Cogn 13(5):689–700. doi: 10.1007/s10071-010-0317-x PubMedCrossRefGoogle Scholar
  5. Call J, Carpenter M (2001) Do apes and children know what they have seen? Anim Cogn 4:207–220CrossRefGoogle Scholar
  6. Hermann E, Wobber V, Call J (2008) Great apes’ (Pan troglodytes, Pan paniscus, Gorilla gorilla, Pongo pygmaeus) understanding of tool functional properties after limited experience. J Comp Psychol 122:220–230CrossRefGoogle Scholar
  7. Mulcahy NJ, Call J (2006) How great apes perform on a modified trap-tube task. Anim Cogn 9:193–199PubMedCrossRefGoogle Scholar
  8. Mulcahy NJ, Schubiger MN, Suddendorf T (2013) Orangutans (Pongo pygmaeus and Pongo abelii) understand connectivity in the skewered grape tool task. J Comp Psychol 127(1):109–113. doi: 10.1037/a0028621 PubMedCrossRefGoogle Scholar
  9. Povinelli DJ (2000) Folk physics for apes: a chimpanzee’s theory of how the mind works. Oxford University Press, Oxford, pp 206–270Google Scholar
  10. Seed AM, Call J, Emery NJ, Clayton NS (2009) Chimpanzees solve the trap problem when the confound of tool-use is removed. J Exp Psychol Anim Behav Proc 35:23–34CrossRefGoogle Scholar
  11. Seed A, Seddon E, Greene B, Call J (2012) Chimpanzee ‘folk physics’: bringing failures into focus. Philos Trans R Soc Lond B Biol Sci 367(1603):2743–2752. doi: 10.1098rstb.2012.0222 PubMedCentralPubMedCrossRefGoogle Scholar
  12. Shumaker RW, Walkup KR, Beck BB, Burghardt GM (2011) Animal tool behavior: the use and manufacture of tools by animals. Johns Hopkins University Press, BaltimoreGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.School of Psychology, McElwain BuildingUniversity of QueenslandSt LuciaAustralia
  2. 2.Anthropological Institute and MuseumUniversity of ZürichZürichSwitzerland

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