Gilby Ian C, Machanda Zarin P, O'Malley Robert C, Murray Carson M, Lonsdorf Elizabeth V, Walker Kara, Mjungu Deus C, Otali Emily, Muller Martin N, Emery Thompson Melissa, Pusey Anne E, Wrangham Richard W
School of Human Evolution and Social Change, and Institute of Human Origins, Arizona State University, Tempe, AZ 85287, USA.
Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA; Department of Anthropology, Tufts University, Medford, MA 02155, USA.
J Hum Evol. 2017 Sep;110:82-94. doi: 10.1016/j.jhevol.2017.06.015. Epub 2017 Jul 20.
Among modern foraging societies, men hunt more than women, who mostly target relatively low-quality, reliable resources (i.e., plants). This difference has long been assumed to reflect human female reproductive constraints, particularly caring for and provisioning mates and offspring. Long-term studies of chimpanzees (Pan troglodytes) enable tests of hypotheses about the possible origins of human sex differences in hunting, prior to pair-bonding and regular provisioning. We studied two eastern chimpanzee communities (Kasekela, Mitumba) in Gombe, Tanzania and one (Kanyawara) in Kibale, Uganda. Relative to males, females had low hunting rates in all three communities, even where they encountered red colobus monkeys (the primary prey of chimpanzees) as often as males did. There was no evidence that clinging offspring hampered female hunting. Instead, consistent with the hypothesis that females should be more risk-averse than males, females at all three sites specialized in low-cost prey (terrestrial/sedentary prey at Gombe; black and white colobus monkeys at Kanyawara). Female dominance rank was positively correlated with red colobus hunting probability only at Kasekela, suggesting that those in good physical condition were less sensitive to the costs of possible failure. Finally, the potential for carcass appropriation by males deterred females at Kasekela (but not Kanyawara or Mitumba) from hunting in parties containing many adult males. Although chimpanzees are not direct analogs of the last common ancestor (LCA) of Pan and Homo, these results suggest that before the emergence of social obligations regarding sharing and provisioning, constraints on hunting by LCA females did not necessarily stem from maternal care. Instead, they suggest that a risk-averse foraging strategy and the potential for losing prey to males limited female predation on vertebrates. Sex differences in hunting behavior would likely have preceded the evolution of the sexual division of labor among modern humans.
在现代觅食社会中，男性狩猎的次数多于女性，女性大多瞄准质量相对较低但稳定的资源（即植物）。长期以来，人们一直认为这种差异反映了人类女性的生殖限制，尤其是照顾配偶和养育后代。对黑猩猩（Pan troglodytes）的长期研究使得在配对结合和定期供应食物之前，能够对人类狩猎中性别差异的可能起源假设进行检验。我们研究了坦桑尼亚贡贝的两个东部黑猩猩群落（卡萨凯拉、米通巴）以及乌干达基巴莱的一个群落（卡尼亚瓦拉）。相对于雄性，在所有这三个群落中雌性的狩猎率都很低，即使在它们与雄性一样经常遇到红疣猴（黑猩猩的主要猎物）的地方也是如此。没有证据表明抱着幼崽会妨碍雌性狩猎。相反，与雌性应比雄性更规避风险这一假设一致的是，所有三个地点的雌性都专门捕食低成本猎物（贡贝的陆生/定居猎物；卡尼亚瓦拉的黑白疣猴）。仅在卡萨凯拉，雌性的优势等级与捕食红疣猴的概率呈正相关，这表明身体状况良好的雌性对可能失败的代价不太敏感。最后，在卡萨凯拉（但不是在卡尼亚瓦拉或米通巴），雄性夺取猎物尸体的可能性阻止了雌性参与有许多成年雄性的群体狩猎。尽管黑猩猩并非人类与黑猩猩最后共同祖先（LCA）的直接类似物，但这些结果表明，在出现关于分享和供应食物的社会义务之前，LCA雌性狩猎的限制不一定源于母性照料。相反，它们表明一种规避风险的觅食策略以及猎物被雄性夺走的可能性限制了雌性对脊椎动物的捕食。狩猎行为中的性别差异可能在现代人类性别分工的进化之前就已存在。
