Kano T
Am J Phys Anthropol. 1984 Jan;63(1):1-11. doi: 10.1002/ajpa.1330630102.
The wild bonobos (Pan paniscus) of Wamba, Zaire have an extremely high frequency of external abnormal traits. Out of 96 animals in a sample comprising all age and sex classes from two different natural groups, 46 individuals had at least one limb defect. The frequency of abnormalities was greater in males than in females, and increased directly with age. Almost all infants and juveniles had completely normal limbs, but virtually all males and over half the females which had reached their prime were found to have one or more limb defects. These findings indicate that congenital factors contribute little to the frequency of abnormalities in this sample. Survival rate is the same in individuals with defects as in those without defects. It appears that individual social status is far more important in procuring foods than locomotor ability. Thus, the operation of such abnormalities as a selective factor in intraspecific competition is minimized in the network of their social relations.
扎伊尔万巴地区的野生倭黑猩猩（Pan paniscus）出现外部异常特征的频率极高。在一个包含来自两个不同自然群体所有年龄和性别的96只动物样本中，46只个体至少有一处肢体缺陷。异常频率在雄性中高于雌性，且随年龄直接增加。几乎所有婴儿和幼崽的四肢完全正常，但几乎所有成年雄性和超过一半成年雌性都被发现有一处或多处肢体缺陷。这些发现表明，先天性因素对该样本中异常频率的影响很小。有缺陷个体的存活率与无缺陷个体相同。看来，个体的社会地位在获取食物方面比运动能力重要得多。因此，在它们的社会关系网络中，此类异常作为种内竞争选择因素的作用被最小化。
