ALBERT

Description: Observations of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) provide valuable comparative data for understanding the significance of conspecific killing. Two kinds of hypothesis have been proposed. Lethal violence is sometimes concluded to be the result of adaptive strategies, such that killers ultimately gain fitness benefits by increasing their access to resources such as food or mates. Alternatively, it could be a non-adaptive result of human impacts, such as habitat change or food provisioning. To discriminate between these hypotheses we compiled information from 18 chimpanzee communities and 4 bonobo communities studied over five decades. Our data include 152 killings (n = 58 observed, 41 inferred, and 53 suspected killings) by chimpanzees in 15 communities and one suspected killing by bonobos. We found that males were the most frequent attackers (92% of participants) and victims (73%); most killings (66%) involved intercommunity attacks; and attackers greatly outnumbered their victims (median 8:1 ratio). Variation in killing rates was unrelated to measures of human impacts. Our results are compatible with previously proposed adaptive explanations for killing by chimpanzees, whereas the human impact hypothesis is not supported.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wilson, Michael L -- Boesch, Christophe -- Fruth, Barbara -- Furuichi, Takeshi -- Gilby, Ian C -- Hashimoto, Chie -- Hobaiter, Catherine L -- Hohmann, Gottfried -- Itoh, Noriko -- Koops, Kathelijne -- Lloyd, Julia N -- Matsuzawa, Tetsuro -- Mitani, John C -- Mjungu, Deus C -- Morgan, David -- Muller, Martin N -- Mundry, Roger -- Nakamura, Michio -- Pruetz, Jill -- Pusey, Anne E -- Riedel, Julia -- Sanz, Crickette -- Schel, Anne M -- Simmons, Nicole -- Waller, Michel -- Watts, David P -- White, Frances -- Wittig, Roman M -- Zuberbuhler, Klaus -- Wrangham, Richard W -- R01 AI 058715/AI/NIAID NIH HHS/ -- England -- Nature. 2014 Sep 18;513(7518):414-7. doi: 10.1038/nature13727.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Anthropology, University of Minnesota, 395 Humphrey Center, 301 19th Avenue South, Minneapolis, Minnesota 55455, USA [2] Department of Ecology, Evolution and Behavior, University of Minnesota, 1987 Upper Buford Circle, St Paul, Minnesota 55108, USA. ; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany. ; 1] Division of Neurobiology, Ludwig-Maximilians Universitaet Muenchen, Germany [2] Centre for Research and Conservation, Royal Zoological Society of Antwerp, Belgium. ; Primate Research Institute, Kyoto University, 41-2 Kanrin, Inuyama, Aichi 484-8506, Japan. ; 1] Department of Evolutionary Anthropology, Duke University, 104 Biological Sciences Building, Box 90383, Durham, North Carolina 27708-0680, USA [2] School of Human Evolution and Social Change, Arizona State University, PO Box 872402, Tempe, Arizona 85287-2402, USA. ; School of Psychology and Neuroscience, University of St Andrews, Westburn Lane, St Andrews, Fife KY16 9JP, UK. ; Wildlife Research Center, Kyoto University, 2-24 Tanaka-Sekiden-Cho, Sakyo, Kyoto, Japan. ; Division of Biological Anthropology, Department of Archaeology &Anthropology, University of Cambridge, Henry Wellcome Building, Fitzwilliam Street, Cambridge CB2 1QH, UK. ; Zoology Department, Makerere University, P.O. Box 7062, Kampala, Uganda. ; 1] Primate Research Institute, Kyoto University, 41-2 Kanrin, Inuyama, Aichi 484-8506, Japan [2] Japan Monkey Center, 26 Kanrin, Inuyama, Aichi 484-0081, Japan. ; Department of Anthropology, University of Michigan, 101 West Hall, 1085 S. University Avenue, Ann Arbor, Michigan 48109, USA. ; Gombe Stream Research Centre, The Jane Goodall Institute - Tanzania, P.O. Box 1182, Kigoma, Tanzania. ; The Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, Chicago, Illinois 60614, USA. ; Department of Anthropology, MSC01-1040, Anthropology 1, University of New Mexico, Albuquerque, New Mexico 87131, USA. ; Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany. ; Department of Anthropology, Iowa State University, 324 Curtiss, Ames, Iowa 50011, USA. ; Department of Evolutionary Anthropology, Duke University, 104 Biological Sciences Building, Box 90383, Durham, North Carolina 27708-0680, USA. ; Department of Anthropology, Washington University in St Louis, Campus Mailbox 1114, One Brookings Drive, St Louis, Missouri 63130, USA. ; University of York, Department of Psychology, Heslington, York, YO10 5DD, UK. ; Department of Anthropology, University of Oregon, Eugene, Oregon 97403, USA. ; Department of Anthropology, Yale University, 10 Sachem Street, New Haven, Connecticut 06511, USA. ; 1] School of Psychology and Neuroscience, University of St Andrews, Westburn Lane, St Andrews, Fife KY16 9JP, UK [2] Universite de Neuchatel, Institut de Biologie, Rue Emile-Argand 11, 2000 Neuchatel, Switzerland. ; Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue Cambridge, Massachusetts 02138, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25230664" target="_blank"〉PubMed〈/a〉

Description: The distribution and abundance of food resources are among the most important factors that influence animal behavioral strategies. Yet, spatial variation in feeding habitat quality is often difficult to assess with traditional methods that rely on extrapolation from plot survey data or remote sensing. Here, we show that maximum entropy species distribution modeling can be used to successfully predict small-scale variation in the distribution of 24 important plant food species for chimpanzees at Gombe National Park, Tanzania. We combined model predictions with behavioral observations to quantify feeding habitat quality as the cumulative dietary proportion of the species predicted to occur in a given location. This measure exhibited considerable spatial heterogeneity with elevation and latitude, both within and across main habitat types. We used model results to assess individual variation in habitat selection among adult chimpanzees during a 10-year period, testing predictions about trade-offs between foraging and reproductive effort. We found that nonswollen females selected the highest-quality habitats compared with swollen females or males, in line with predictions based on their energetic needs. Swollen females appeared to compromise feeding in favor of mating opportunities, suggesting that females rather than males change their ranging patterns in search of mates. Males generally occupied feeding habitats of lower quality, which may exacerbate energetic challenges of aggression and territory defense. Finally, we documented an increase in feeding habitat quality with community residence time in both sexes during the dry season, suggesting an influence of familiarity on foraging decisions in a highly heterogeneous landscape.