Navigation strategies in three nocturnal lemur species: diet predicts heuristic use and degree of exploratory behavior
Humans generally solve multi-destination routes with simple rules-of-thumb. Animals may do the same, but strong evidence is limited to a few species. We examined whether strepsirrhines, who diverged from haplorhines more than 58 mya, would demonstrate the use of three heuristics used by humans and supported in vervets, the nearest neighbor rule, the convex hull, and a cluster strategy, when solving a multi-destination route. We hypothesized that the evolution of these strategies may depend on a species’ dietary specialization. Three nocturnal lemur species were tested on an experimental array at the Duke Lemur Center. Frugivorous fat-tailed dwarf lemurs (Cheirogaleus medius) were expected to follow paths most consistent with distance-saving navigational heuristics because fruit trees are stationary targets. Gray mouse lemurs (Microcebus murinus) and aye-ayes (Daubentonia madagascariensis), which rely on more mobile and ephemeral foods, were expected to use fewer paths consistent with these heuristics and be more exploratory. Our data supported all of these hypotheses. Dwarf lemurs used paths consistent with all three heuristics, took the shortest paths, and were the least exploratory. Mouse lemurs were quite exploratory but sometimes used paths consistent with heuristics. Aye-ayes showed no evidence of heuristic use and were the most exploratory. Distinguishable patterns of inter- and intra-individual variation in ability to solve the route, speed, and behavior occurred in each species. This research suggests that these simple navigational heuristics are not part of a readily available set of cognitive tools inherited by all primates but instead evolve due to need in each lineage.
KeywordsStrepsirrhines Traveling salesman problem Optimal Hamiltonian path problem Shortest path problem Heuristics Dietary strategy Inter-individual variation
We thank Erin Ehmke and the staff at the Duke Lemur Center for assistance in carrying out this study. We are especially grateful to David Brewer, who built the apparatuses and was invaluable during the whole data collection process. This research was funded by Duke University and the University of Toronto. This is Duke Lemur Center publication #1411.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
The research methods were non-invasive and were approved by the Duke University IACUC.
- Constable ID, Mittermeier RA, Pollock JI, Ratsirarson J, Simons H (1985) Sightings of aye-aye and red ruffed lemurson Nosy Mangable and the Masoala peninsula. Primate Conserv 5:59–62Google Scholar
- Feistner ATC, Sterling EJ (1995) Body mass and sexual dimorphism in the aye-aye, Daubentonia madagascariensis. Dodo 31:73–76Google Scholar
- Gigerenzer G (2000) Adaptive thinking: rationality in the real world. Oxford University Press, OxfordGoogle Scholar
- Gigerenzer G (2008) Fast and frugal heuristics: the tools of bounded rationality. In: Koehler DJ, Harvey N (eds) Blackwell handbook of judgment and decision making. Wiley-Blackwell, New Jersey, pp 62–88Google Scholar
- Gigerenzer G, Todd PM, the ABC Research Group (1999) Simple heuristics that make us smart. Oxford University Press, OxfordGoogle Scholar
- Golden BL, Stewart WR Jr (1985) Empirical analysis of heuristics. In: Lawler EL, Lenstra JK, Rinooy Kan AHG, Schmoys DB (eds) The traveling salesman problem: a guided tour of combinatorial optimization. Wiley, New Jersey, pp 207–249Google Scholar
- Hammerstein P, Stevens JR (2012) Six reasons for invoking evolution in decision theory. In: Hammerstein P, Stevens JR (eds) Evolution and the mechanisms of decision making. Ernst Strüngmann Forum Report, vol 11. MIT Press, Cambridge, pp 1–17Google Scholar
- Hladik CM, Charles-Dominque P, Petter JJ (1980) Feeding strategies of five nocturnal prosimians in the dry forest of the west coast of Madagascar. In: Charles-Dominque P, Cooper HM, Hladik A, Hladik CM, Pages E, Pariente GF, Petter-Rousseaux A, Schilling A, Petter JJ (eds) Nocturnal Malagasy primates: ecology, physiology and behavior. Academic Press, New York, pp 41–74Google Scholar
- Janson C (2000) Spatial movement strategies: theory, evidence, and challenges. In: Boinski S, Garber PA (eds) On the move: how and why animals travel in groups. University of Chicago Press, Chicago, pp 165–203Google Scholar
- Kumpan LT, Rothman JM, Chapman CA, Teichroeb JA (in prep) Nutritional determinants of vervet monkey (Chlorocebus pygerythrus) foraging decisions in multi-destination routes. Google Scholar
- Lawler EL, Lenstra JK, Rinooy Kan AHG, Schmoys DB (1985) The traveling salesman problem: a guided tour of combinatorial optimization. Wiley, New JerseyGoogle Scholar
- MacGregor JN, Chu Y (2011) Human performance on the traveling salesman and related problems: a review. J Probl Solv 3:1–29Google Scholar
- Martin RD (1972) A preliminary field-study of the lesser mouse lemur (Microcebus murinus J.F. Miller 1777). Adv Ethol 9:43–89Google Scholar
- Nunn CL (2011) Developing a comparative database and targeting future data collection. The comparative approach in evolutionary anthropology and biology. The University of Chicago Press, Chicago, pp 299–316Google Scholar
- Petter JJ (1962) Ecologie et éthologie des lémuriens malgaches. Mém Mus Hist Nat Sér A 27:1–146Google Scholar
- Petter JJ (1977) The aye-aye. In: Primate Conservation. Prince Rainier of Monaco, Bourne. Academic Press, New York, pp 37–57Google Scholar
- Petter JJ, Peyrieras A (1970) Nouvelle contribution a l’etude d’un lemurien Malagache, le aye-aye (Daubentonia madagascariensis E. Geoffroy). Mammalia 34:167–193Google Scholar
- Randimbiharinirina DR, Raharivololona BM, Hawkins MTR, Frasier CL, Culligan RR, Sefczek TM, Randriamampionona R, Louis EE Jr (2018) Behaviour and ecology of male aye-ayes (Daubentonia madagascariensis) in the Kianjavato Classified Forest, Southeastern Madagascar. Folia Primatol 89:123–137CrossRefGoogle Scholar
- Shettleworth SJ (2000) Modularity and the evolution of cognition. In: Heyes CM, Huber L (eds) The evolution of cognition. MIT Press, Cambridge, pp 43–60Google Scholar
- Stephens DW, Krebs JR (1986) Foraging theory. Princeton University Press, PrincetonGoogle Scholar
- Winkler H, Leisler B (1999) Exploration and curiosity in birds: functions and mechanisms. In: Proceedings of the 22nd international ornithological congress, Durban. Birdlife South Africa, Johannesburg, pp 915–932Google Scholar