Change point analysis of travel routes reveals novel insights into foraging strategies and cognitive maps of wild baboons

Efficient space use is a critical challenge for animals relying on stationary resources. It is often difficult with purely observational methods to gain unambiguous insight into any ability of primates to manage and process spatial information. Investigating the visible signs of the decision processes underlying space use often leaves open important issues. We applied the change point test [Byrne et al. (2009). Anim Behav 77: 619–631], a statistical tool to objectively determine change points (CPs) in animal travel paths, to investigate to what degree directional changes in our study group's (Papio ursinus) dry season ranging were associated with important resources and prominent landmarks. One‐third of directional changes were associated with fruit feeding, 1/3 with traveling, and 1/3 with dry matter feeding, travel feeding and with drinking. When directional changes were associated with traveling, the subsequent directional changes were likely to result in fruit feeding. Fruit feeding mostly occurred at the apex of the day journeys, while drinking, dry matter feeding, and travel feeding often occurred along straight travel segments. The majority of directional changes did not occur in clusters at distinctive locations, but at distances of more than 120 m apart from each other, many of them along prominent landmarks. We conclude that the CPs do not represent nodes or route bends of a network map. Rather, they represent (1) locations where the decision to turn back to their sleeping site was taken, and (2) locations next to important landmarks (changes of slope, car tracks) where slight adjustment of a movement direction was possible. We found no evidence for a Euclidean map and discuss our findings in the light of a network map representation of space. Am. J. Primatol. Am. J. Primatol. 76:399–409, 2014. © 2013 Wiley Periodicals, Inc.

[1]  J. Altmann,et al.  Baboon Ecology: African Field Research , 1970 .

[2]  P. Garber,et al.  Role of spatial memory in primate foraging patterns: Saguinus mystax and Saguinus fuscicollis , 1989, American journal of primatology.

[3]  Do solitary foraging nocturnal mammals plan their routes? , 2011, Biology Letters.

[4]  Richard W. Byrne,et al.  Mental maps in chacma baboons (Papio ursinus): using inter-group encounters as a natural experiment , 2007, Animal Cognition.

[5]  C. Janson Experimental evidence for spatial memory in foraging wild capuchin monkeys, Cebus apella , 1998, Animal Behaviour.

[6]  K. Milton Distribution Patterns of Tropical Plant Foods as an Evolutionary Stimulus to Primate Mental Development , 1981 .

[7]  Richard W. Byrne,et al.  Travel routes and planning of visits to out-of-sight resources in wild chacma baboons, Papio ursinus , 2007, Animal Behaviour.

[8]  Andrew S. Knell,et al.  Classifying area-restricted search (ARS) using a partial sum approach , 2011, Theoretical Ecology.

[9]  Joan B. Silk,et al.  On the Move. How and Why Animals Travel in Groups. , 2000 .

[10]  H. Sigg,et al.  Home range and daily march in a Hamadryas baboon troop. , 1981, Folia primatologica; international journal of primatology.

[11]  Christophe Boesch,et al.  Sophisticated Euclidean maps in forest chimpanzees , 2009, Animal Behaviour.

[12]  R. Byrne,et al.  Machiavellian intelligence : social expertise and the evolution of intellect in monkeys, apes, and humans , 1990 .

[13]  C. Anderson Beach troop of the Gombe , 1982, International Journal of Primatology.

[14]  W. Hamilton Baboon sleeping site preferences and relationships to primate grouping patterns , 1982, American journal of primatology.

[15]  J. Mackinnon The behaviour and ecology of wild orang-utans (Pongo pygmaeus) , 1974 .

[16]  C R Gallistel,et al.  Computations on metric maps in mammals: getting oriented and choosing a multi-destination route. , 1996, The Journal of experimental biology.

[17]  P. Harvey,et al.  Relative brain size and ecology in birds , 2009 .

[18]  Paul H. Harvey,et al.  Primates, brains and ecology , 2009 .

[19]  R. W. Byrne,et al.  How did they get here from there? Detecting changes of direction in terrestrial ranging , 2009, Animal Behaviour.

[20]  E. Sue Savage-Rumbaugh,et al.  Bonobo (Pan paniscus) Spatial Memory and Communication in a 20-hectare Forest , 2002, International Journal of Primatology.

[21]  P. Garber,et al.  Testing Learning Paradigms in the Field , 1996 .

[22]  Richard W. Byrne,et al.  How do wild baboons (Papio ursinus) plan their routes? Travel among multiple high-quality food sources with inter-group competition , 2009, Animal Cognition.

[23]  TESTING LEARNING PARADIGMS IN THE FIELD Evidence for Use of Spatial and Perceptual Information and Rule-Based Foraging in Wild Moustached Tamarins , 1996 .

[24]  Anthony Di Fiore,et al.  Route-based travel and shared routes in sympatric spider and woolly monkeys: cognitive and evolutionary implications , 2007, Animal Cognition.

[25]  E. Erhart,et al.  Spatial Memory during Foraging in Prosimian Primates: Propithecus edwardsi and Eulemur fulvus rufus , 2008, Folia Primatologica.

[26]  J. Fleagle Apes and Humans , 2013 .

[27]  C. Boesch,et al.  Mental map in wild chimpanzees: An analysis of hammer transports for nut cracking , 1984, Primates.

[28]  C. Menzel,et al.  Unprompted recall and reporting of hidden objects by a chimpanzee (Pan troglodytes) after extended delays. , 1999, Journal of comparative psychology.

[29]  G. D. Fuller Vegetation of South Africa , 1917, Botanical Gazette.

[30]  Charles H. Janson,et al.  Experimental evidence for route integration and strategic planning in wild capuchin monkeys , 2007, Animal Cognition.

[31]  K. Milton,et al.  Foraging behaviour and the evolution of primate intelligence. , 1988 .

[32]  W. Brockelman,et al.  Gibbon travel paths are goal oriented , 2011, Animal Cognition.

[33]  B. Poucet Spatial cognitive maps in animals: new hypotheses on their structure and neural mechanisms. , 1993, Psychological review.

[34]  Audrey E. Cramer,et al.  Vervet monkeys as travelling salesmen , 1997, Nature.

[35]  V. Carey,et al.  Mixed-Effects Models in S and S-Plus , 2001 .