The age-sex composition of provisioned groups of Japanese monkeys (Macaca fuscata yakui) was investigated along the Anbo Road in the southeast of Yakushima island, Japan. The monkeys had been provisioned on an irregular basis by tourists passing through by car or bus. Group size, age-sex composition and socionomic sex ratio were no different from those of purely wild groups of monkeys in Yakushima, as reported by Maruhashi (1982). However, the proportion of females with infants of 7-9 months old in a group on the Anbo Road was estimated to be higher than that for non-provisioned groups. The reason for this could be improvement of nutritional condition as a result both of provisioning by tourists, and of feeding on high quality herbs planted on large, artificial slopes which flank several sections of the Anbo Road.

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It has been proposed that the rate of scratching may be a good behavioral measure of social tension. A case study was conducted to examine the expression of social tension, with particular emphasis on scratching rate, during the intergroup transfer of a 5-year-old male Japanese macaque (Macaca fuscata). This male was frequently involved in agonistic interactions during the course of transfer from the natal group to a neighboring group. Mounting before grooming sessions was frequently observed at the first stage of transfer. During the course of immigration, scratching rate decreased gradually when the male was not in close proximity to members of the neighboring group. Scratching rate was lower when the male was receiving grooming compared with before or after a grooming session. A decrease in scratching rate before and after grooming sessions was found when the male was in the natal group, while no such tendency was found when he was in the neighboring group. It is suggested that scratching can be used as a behavioral measure of social tension both in the field studies as well as in the captive studies.

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Semithin sections have been used for the study of the fine structure of cells and tissues by light microscopy, correlation with light and electron microscopy and high voltage electron microscopy in the primates.
In order to examine semithin sections under a light and an electron microscope including a high voltage electron microscope, some embedding methods employing water-miscible methacrylates and epoxy resins have been developed. These embedding methods have been devised for ease in embedding, infiltration, sectioning and staining. Staining with basic and acids dye is sharp and brilliant by light microscopy. Various histochemical reagents have been found suitable for use with semithin sections.
The same cell or structure can be identified in a semithin section when it is examined under an electron microscope after observation by light microscopy. Each type of microscope has both advantages and limitations. Low resolving power is a serious limitation in light microscopy, although it allows the visualization of large area, structures or tissues. Examination under electron microscopy allows the detailed cellular structures with the difficulty of the orientation in the specimen. The limitations of one type of microscopy can be circumvented by using an additional microscopical system. Correlation methods are, therefore, useful in resolving doubts in the correct interpretation of a microscopic image in the study of the primates.
An additional advantage of semithin sections is the study for the three-dimensional structures, which can be combined with high voltage electron microscopy. In some studies, the information of the three-dimensional structures is necessary.
The approaches are applicable to solving divergent problems in primatology.

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The workshop “Polyspecific Associations of Rain Forest Primates” was held at the Max-Plank Institute in Seewiesen, Germany from 15 to 22 January 1995. This workshop focused on the Taï Monkey Project, a research project on polyspecific associations of monkeys in the TAÏ NATIONAL PARK, IVORY CAST. A brief summary of the workshop and a short introduction of the Taï Monkey Project are provided.
Since Dr. Ronald Noë started this project in 1991, detailed studies on polyspecific associations of seven sympatric monkey species, especially between red colobus monkeys and diana monkeys in terms of predator avoidance by red colobus monkeys, have been carried out. Two hypotheses were tested. The first hypothesis states that, at least one of the two species can reduce the risk of predation by making polyspecific associations. The second states that, at least one of the two species can obtain food more efficiently when they are in such associations.
A summary of the results is as follows. For red colobus monkeys, polyspecific associations with diana monkeys functions as a strategy to avoid predation, notably by chimpanzees. There is a considerable predation pressure by chimpanzees on red colobus monkeys in the Taï Forest. The diana monkeys probably benefit from improved protection against other predators, especially crowned eagles and leopards. On the other hand, there is no evidence that either red colobus monkeys or diana monkeys obtain any advantage in foraging by making such associations.
Further effort is necessary to completely answer the question why monkeys form polyspecific associations.

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