Comparative ecology of primates in West Africa

1987年在几内亚Bossou、Kala Maloue国家公园和喀麦隆Campo动物保护区进行的实地研究获得的数据已被分析并部分发表。每个研究领域的结果总结如下。几内亚研究小组在靠近几内亚-利比里亚边境的Bossou研究了野生黑猩猩的种群动态、工具使用行为、性行为和其他社会行为。自1976年以来，这群黑猩猩一直在没有人工喂养的情况下进行研究，以便获得长期数据。通过一只年轻雄性黑猩猩的死亡，提供了种群动态的新数据。过去该群体的黑猩猩自然死亡的其他一些案例也得到了澄清。死亡黑猩猩的体型比同年龄饲养的黑猩猩要小。对使用工具的实验和观察研究，用天然石锤和铁砧敲碎油棕榈，揭示了这种行为的灵活性和最优性：当没有石头时，黑猩猩很容易使用替代材料（木材）；他们运送石头和棕榈种子；他们偏爱特定大小的石头和特定年份的棕榈坚果；石头的作用并不是固定的。此外，我们还发现了博苏黑猩猩未发现的二次（元）工具的使用和蚂蚁浸渍的痕迹。我们的研究揭示了黑猩猩的高识别能力支持各种工具使用行为，并提出了将生态学与心理学联系起来的丰硕成果。我们对性行为的研究主要集中在女性性周期和男性数量之间的关系。雌性黑猩猩的发情期周期在雄性充足时是同步的，而在雄性不足时则不是。建议根据雄性资源的数量进行适应性转换。对黑猩猩裂变聚变原因的分析正在进行中。它将澄清裂变-聚变与食物供应之间的关系；角色扮演和社会环境等等。以热带稀树草原猴（Erythrocebus patas）和热带稀树草原猴（cercopithecus aethiops）为研究对象，对生活在Kala Maloue热带稀树草原的猕猴摄食生态学进行了比较。这些草原适应物种在摄食和测距行为上的差异如下。野猴主要分布于草地，活动范围约6 km^2，旱季日活动距离约6 km。相反，稀树草原猴主要分布在河流森林，有时也分布在草原。归途距离仅约1 km^2，日行程距离约为2 km。这两个物种主要以几种木本植物的果实、种子、花和金合欢树的树胶为食。此外，斑猴吃昆虫（如蚱蜢、象鼻虫和不明昆虫的幼虫）和动物（鸡、蜥蜴）。另一方面，热带草原猴子有时吃昆虫，但很少见面。取而代之的是，它们以河边几种草本植物的叶片为食。这些饮食上的差异可能会影响这两个物种的蛋白质摄入量。因此，更多的蛋白质摄入可以使它们在旱季繁殖。自1985年以来，通过人工喂养研究了坎波黑猩猩的社会结构和工具使用行为。在研究期间，在人工喂食点，可以从盲眼内观察到一些黑猩猩。大多数来到觅食地点的黑猩猩都是单独的，或者是两匹的小队伍，偶尔也有四匹或更多，最多有九匹，包括成年和未成年的两性。Sugiyama于1985年报道了Campo保护区黑猩猩使用工具的行为。在本研究中，收集了白蚁丘挖棒特性的额外数据。研究了白蚁挖掘的频率和季节性。几种植物似乎被选择作为挖棒的材料，白蚁的挖棒行为频率很低。少

The data obtained from field studies in 1987 at Bossou, Guinea, Kala Maloue National Park and Campo Animal Reserve, Cameroon have been analyzed and partly published. Summary of the result in each study area was described below.Guinea team studied on population dynamics, tool-using behavior, sexual behavior, and other social behaviors of wild chimpanzees at Bossou, near Guinea-Liberia border. The group of chimpanzees have been studied since 1976 without artificial feeding, so that the long term data are available. New data on population dynamics was given through the death of a young male chimpanzees. Some other cases of natural death of the chimpanzees of the group in the past were clarified. The body size of the dead chimpanzee was smaller than that of reared chimps in the same age. Experimental and observational studies on tool-using, oil-palmnut cracking with natural stone hammers and anvils, revealed flexibility and optimality in the behavior: the chimps easily use substitutable ma … More terials (woods) when stones were not available; they conveyed both stones and palm-seeds; they preferred particular size of stones and particular oldness of palm-nuts; the role of stones was not fixed. We also recorded the use of secondary (meta) tool and the traces of ant dipping which had not been recorded in the Bossou chimps. Our study revealed chimpanzee's high ability of recognition supporting various tool-using behavior, and suggested fruitful result by linking ecology with psycology. Our study on sexual behavior focused on the relationship between female sexual cycles and the number of males. The estorus cycles of female chimpanzees were synchronized when males were sufficient, and not when insufficient. Adaptational switching according to the amount of male resources was suggested. The analysis on the cause for chimpanzee fission-fusion are now undergoing. It will be clarified the relation between fission-fusion and food availability; role playing and social contexts, and so on.Comparative feeding ecology of monkeys living in the savanna-grassland in Kala Maloue was carried out for patas monkeys (Erythrocebus patas) and savanna monkeys (cercopithecus aethiops). These savanna adapted species were revealed to be different in feeding and ranging behavior as follows. Patas monkeys ranged mainly in grassland, home range was about 6 km^2, and daily travel distance was about 6 km during dry season. On the contrary, savanna monkeys ranged mainly in riverine forest, sometimes in grassland. Home range was only about 1 km^2, and daily travel distance was about 2 km. Both species fed mainly on fruits of several woody plant, seeds, flowers and gum of Acacia trees. In addition, patas monkeys ate insects (e.g., grasshoppers, weevils and lavaes of unidentified insects) as well as meet (chickens, lizards). On the other hand, savanna monkeys sometimes ate insects but hardly did meet. Instead of this, they fed on blades of several herbaceous plant at riverside. These differences in thier diet may affect the protein intake in the two species. As a result, larger protein intake of patas monkeys may enable them to breed in dry season.Social structure and tool-using behavior of chimpanzees were studied of Campo through artificial feeding since 1985. Some chimpanzees could be observed from inside of the blind at the artificial feeding site during this study period. Most of chimpanzees which came into the feeding site were alone or in small parties of two individuals, occasionally four or more, nine in maximum, containing both sexes of adults and immatures. Sugiyama reported tool-using behavior of chimpanzees in Campo Reserve in 1985. In this study, additional data on the characteristics of termite mound digging sticks were collected. The frequency and the seasonality of termite digging was also studied. Several species of plant seemed to be chosen as the material of digging sticks, and the frequency of termite digging behavior was very low. Less