Local behavioral variations and acquisition processes of cultural behavior patterns among wild chimpanzees

我们走访了六个黑猩猩的野外地点：马哈勒、贡贝(坦桑尼亚)、坎亚瓦拉、恩戈戈、布东戈(乌干达)和博苏(几内亚)，并比较了它们之间的行为模式。我们还研究了马哈勒文化行为的发展。我们发现了许多行为上的局部差异，如社交抓挠、梳理发声、玩耍、接触水的行为、恐吓展示、求爱展示和自我药物治疗。马哈勒的许多少年和老婴儿都表现出一种名为“拉树叶堆”的游戏模式，并至少坚持了10多年。然而，这种模式并没有被证实在其他地方作为一种传统存在。马哈勒的幼崽们对溪流的流水表现出不同的游戏模式。面对水面，几个男性少年和青少年可能会纵向猛烈地摇头，仿佛享受着自己镜像的运动。几个青少年从事所谓的“海绵树叶”，也使用…更多的叶中脉也有类似的用途。这种多样化的水上游戏模式可能是时尚或早期的传统，因为它们很可能是从一个青少年传给另一个青少年的，但从视频剪辑中观察到，2000年和1994年之间有一些细微的行为差异。极有可能的是，恐吓性表演，如“泼水”，以及求偶表演，如“剪叶”和“灌木弯曲”，很可能是黑猩猩的传统。在马哈勒，新记录的“脚后跟踢”、“外寄生虫的手掌挤压”和“性皮肤的相互接触”等模式从未被观察到。在Mahale的一项纵向研究证明，个体获得文化模式的顺序是：首先是喂食行为，然后是梳理行为，然后是工具使用和求爱展示，最后是恐吓展示。到断奶期间，它们可能会获得几乎所有的传统。社会学习过程被认为是形成“修饰-握手”的过程，在这个过程中，母亲可能会教她们的婴儿如何通过“塑造”来握手。一只成年雌性在迁移到新的一组后，即使在20年后，仍然保持着她原来的组的扣环模式。个体的创新很可能在野生黑猩猩中反复发生，但可能很少被固定为一种文化模式。我们可以在黑猩猩身上发现许多局部行为差异的事实，可能部分解释为从一个群体传播到另一个群体的缓慢过程。为了研究父子之间的相似性，我们收集了所有M群个体的粪便等DNA样本，并正在分析Y染色体上的基因。较少

We visited six field sites of chimpanzees: Mahale, Gombe (Tanzania), Kanyawara, Ngogo, Budongo (Uganda), and Bossou (Guinea) and compared their behavioral patterns among them. We also studied the development of the cultural behavior at Mahale. We discovered many local differences in behavior such as patterns of social scratch, grooming vocalizations, play, water contact behavior, intimidation displays, courtship displays, and self-medications. A play pattern named "Leaf-pile pulling" is shown by many juveniles and old infants of Mahale and has persisted for at least more than 10 years. However, this pattern has not been confirmed to exist as a tradition elsewhere. Juveniles at Mahale show various play patterns in response to running water of streams. Facing with the water surface, several male juveniles and adolescents may shake their head longitudinally violently as if enjoying the movements of their own mirror images. Several juveniles engage in so-called "leaf-sponging" and also use … More the leaf midrib for the similar purpose. Such diversified patterns of water play may be fashions or incipient traditions since they have a likelihood of having been transmitted from a juvenile to another, but there are some subtle behavioral differences between 2000 and 1994 as observed in video clips. It is very likely that intimidation displays such as "Throw splash" and courtship displays such as "Leaf-clipping" and "Shrub-bend" are among the traditions of Mahale chimpanzees. Patterns such as "Heel kick," "Palm squash of ecto-parasites," and "mutual touching of sexual skin" that have been newly recorded at Bossou have never been observed at Mahale. From a longitudinal study at Mahale, it has proved that individuals acquire cultural patterns sequentially: first feeding behavior then grooming behavior, and followed by tool-using and courtship displays, and finally intimidation displays. It is likely that they acquire almost all traditions by the weaning period. Social learning process has been suggested for the formation of "Grooming-hand-clasp," in which mothers may teach their infant offspring how to grasp hands by "molding." An adult female was shown to keep the mode of clasp pattern of her old group even 20 years after her immigration to a new group. Innovation by individuals likely occurs repeatedly among wild chimpanzees, but may rarely be fixed as a cultural pattern. The fact that we can find many local behavioral differences in chimpanzees may be partly explained by the slow process of dissemination from a group to another. In order to investigate the similarity between fathers and offspring, we have collected DNA sample such as feces from all the individuals of M group and are analyzing genes on the Y-chromosome. Less