Adaptive significance of fission-fusion society in Ateles

我们在哥伦比亚马卡雷纳的雨林中对野生蜘蛛猴（belzebuth）进行了为期三年的研究。众所周知，蜘蛛猴的父系群体和成员在较小的和短暂的聚集中移动，称为党派，重复裂变和融合。通过一种划时代的方法，我们可以比以前更清楚地了解蜘蛛猴的这种独特的群体模式：在完全确定群体成员之后，由多个观察者同时观察群体中的多个群体和各方。同时，通过对食物菜单和消费、重要食物榕属植物物候学、种子传播等植物生态学研究，进一步明确了这一类群与森林环境的适应意义。以下是本研究获得的最重要的结果。1. 水果生产季节变化与成组模式的关系。2. 男性和女性在集体家庭范围内使用面积差异的意义。3. 雄性在群体边界附近的巡逻行为及其特有的亲缘关系。4. 长呼叫的频率和功能与分组模式的关系。5. 群体间的相互作用。6. 父系社会中女性转移与性成熟或生殖的关系。7. “salado”使用的季节性和“salado”的特殊分组。8. 蜘蛛猴传播榕树和树果属植物种子的优缺点。9. 在新形成的沙洲上，原野范围的扩大与森林形成的关系。10. 森林结构与猴子的活动路线或睡眠地点之间的关系。

We made a three-years studies of wild spider monkeys (Ateles belzebuth) in the rain forest at Macarena, Colombia. It is known that the group of spider monkeys in patrilineal and the members move in smaller and temporal aggregations called parties which repeat fission and fusion. We could succeed to know this unique grouping pattern of spider monkeys much clearer than before by employing an epoch-making method: simultaneous observation of plural groups and parties in a group by plural observers after complete identification of the group members. At the same time, adaptive significance of the grouping was made clearer in relation with forest environment from the studies of foodmenu and consumption, plant phenology of Ficus and Oenocarpus, which are among the most important foods, seed dispersal, and other plant ecological studies.The following are the most important results obtained from this study. 1. Relation between seasonal change of fruits production and grouping pattern. 2. Significance of difference in utilized area in a group home range between males and females. 3. Patroll behavior of males and the peculiar affinitivenes among them around the frontier of the group range. 4. Frequency and function of long calls in relation with grouping pattern. 5. Agonistic interaction between groups. 6. Relation between female transfer and sexual maturity or reproduction in the patrilineal society. 7. Seasonality of "salado" usage and peculiar grouping at "salado". 8. "merits and demerits" in seed dispersal of Ficus and Oenocarpus by spider monkeys. 9. Extension of home range in relation with forest formation on the newly-formed sandbank. 10. Reration between forest structure and traveling routes or sleeping sites of the monkeys.