The Relationship of Foraging Strategy and Social Organization in Western Lowland Gorillas and Chimpanzees

对于某种特定类型的社会制度演变的根本原因，人们没有达成共识。一种流行的假设是，类人猿社会组织的差异主要是觅食行为差异的结果；食物数量和分布的差异（空间上和时间上）导致群体内喂养竞争的不同程度，这反过来又是社会组织差异的潜在原因。非洲猿类的社会组织有很大的不同，山地大猩猩群体是有凝聚力的，而黑猩猩和倭黑猩猩群体则没有凝聚力。他们的饮食也有相当大的差异。山地大猩猩因其栖息地而以叶为食，而黑猩猩和倭黑猩猩以水果为食，其资源在时间和空间上分布不均匀。因此，这似乎与刚才描述的假设是一致的。然而，虽然我们对山地大猩猩的行为了解得很多，但对西部低地大猩猩的习性却知之甚少，尽管它们的数量更多。更有趣的是，西部低地大猩猩的饮食记录较少，但看起来比山地大猩猩吃得多，而且可能与黑猩猩的饮食非常接近。这项研究项目将由一位年轻而坚定的科学家进行，将建立低地山地大猩猩的研究条件（习惯化），并研究这一问题以及猿的社会性和行为中的其他重要问题。如果我们要分离出解释我们近亲中各种社会组织的因素，并最终确定形成早期人类社会组织的因素，这是至关重要的。

There is no consensus on the underlying cause of the evolution of a particular type of social system. One popular hypothesis is that the differences in great ape social organization, in particular, are primarily the result of differences in foraging behavior; that differences in the quantity and distribution of food (both spatially and temporally) result in differing levels of within-group feeding competition, which in turn is the underlying cause for differences in social organization. The African apes differ considerably in their social organizations, with mountain gorilla groups being cohesive, and chimpanzee and bonobo groups being non-cohesive. There are also considerable differences in in their diets. Mountain gorillas are leaf-eaters because of their habitat, while chimpanzees and bonobos are primarily fruit eaters, and their resources are distributed unevenly in time and space. This therefore appears compatible with the hypothesis just described. However, while a great deal is known about mountain gorilla behavior, little is known about the habits of western lowland gorillas, even though they are the more numerous. More interestingly, the diet of the western lowland gorilla is less well documented, but looks to be considerably more frugivorous than that of the mountain gorilla, and may be very close to that of the chimpanzee. This research project, to be conducted by a young and committed scientist, will establish study conditions (habituation) with lowland mountain gorillas and study this and other important questions in ape sociality and behavior. This is essential if we are ever to isolate the factors that explain the diverse array of social organizations in our close relatives, and ultimately, if we are to identify the factors which shaped early human social organization.