title: Selective insectivory at Toro-Semliki, Uganda: comparative analyses suggest no 'savanna' chimpanzee pattern.
abstract: Chimpanzee (Pan troglodytes) insectivory across Africa is ubiquitous. Insects provide a significant nutritional payoff and may be important for chimpanzees in dry, open habitats with narrow diets. We tested this hypothesis at Semliki, Uganda, a long-term dry study site. We evaluated prospects for insectivory by measuring insect abundance along de novo transects and trails, monitoring social insect colonies, and surveying available raw materials for elementary technology. We determined the frequency and nature of insectivory through behavioral observation and fecal analysis. We then compared our results with those from 15 other long-term chimpanzee study sites using a cluster analysis. We found that Semliki chimpanzees are one of the most insectivorous populations studied to date in terms of frequency of consumption, but they are very selective in their insectivory, regularly consuming only weaver ants (Oecophylla longinoda) and honey and bees from hives of Apis mellifera. This selectivity obtains despite having a full range of typical prey species available in harvestable quantities. We suggest that Semliki chimpanzees may face ecological time constraints and therefore bias their predation toward prey taxa that can be quickly consumed. Geographical proximity correlated with the results of the cluster analysis, while rainfall, a relatively gross measure of environment, did not. Because broad taxonomic groups of insects were used in analyses, prey availability was unlikely to have a strong effect on this pattern. Instead, we suggest that transmission of cultural knowledge may play a role in determining chimpanzee prey selection across Africa. Further study is needed to test these hypotheses.
authors.affiliation: Department of Anthropology, Miami University, 120 Upham Hall, 100 Bishop Circle, Oxford, OH 45056-1879, USA; Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, Fitzwilliam Street, Cambridge CB2 IQH, UK; Department of Anthropology, Yale University, 10 Sachem Street, New Haven, CT 06511-3707, USA. Electronic address: twebster17@gmail.com.
authors.forename: Timothy H
authors.initials: TH
authors.lastname: Webster
authors.affiliation: Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, Fitzwilliam Street, Cambridge CB2 IQH, UK.
authors.forename: William C
authors.initials: WC
authors.lastname: McGrew
authors.affiliation: Department of Anthropology, Miami University, 120 Upham Hall, 100 Bishop Circle, Oxford, OH 45056-1879, USA.
authors.forename: Linda F
authors.initials: LF
authors.lastname: Marchant
authors.affiliation: Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, Fitzwilliam Street, Cambridge CB2 IQH, UK.
authors.forename: Charlotte L R
authors.initials: CL
authors.lastname: Payne
authors.affiliation: Department of Anthropology, Indiana University, Student Building 130, 701 E Kirkwood, Bloomington, IN 47405, USA.
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Hunt
mesh_terms: D000818:Animals; D004032:Diet; D004777:Environment; D005243:Feces / Q000737:chemistry; D020387:Food Chain; D007313:Insecta / Q000502:physiology*; D002679:Pan troglodytes / Q000502:physiology*; D011235:Predatory Behavior; D014454:Uganda
keywords: Diet; Entomophagy; Hymenoptera; Isoptera; Pan troglodytes; Predation