We conducted quantitative analyses of the cross-sectional shape of the distal radial shaft in twelve species of macaques, which differ in locomotor behavior: mainly relatively terrestrial rhesus macaques (Macaca mulatta) and arboreal crab eating macaques (Macaca fascicularis). We took pQCT scans of the distal radial shafts of a total of 338 specimens at the level of the inferior radio-ulnar articulation. From each pQCT image, the periosteal outline of the radius was traced by a digital imaging technique. We determined seven points (landmarks) on the outline by developing a standardized morphometric technique. Bone surface lengths were measured by using these landmarks, and their soft tissue (muscle) correlates were investigated. The results were: both of Macaca mulatta and Macaca fascicularis was not different from other macaque species for any muscle indices. On the other hand, the arboreal Macaca fascicularis has relatively larger tendon grooves for Mm. extensor carpi radialis longus et brevis at the distal radius rather than those of Macaca mulatta. The muscle index for Mm. extensor carpi radialis longus et brevis seems to reflect the positional habit and functional demand of the forearm during arboreal activity in Macaca fascicularis. We discuss whether the distal region of the radius reflects muscular development, and is an important region for investigating locomotor adaptations in primates. The present study may contribute to the possibility of using this type of morphometric analysis for reconstructing the positional behavior of fossil primates.

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Japanese macaques at "monkey parks" are suitable as subject animals for science education because they are of great interest to students due to their physical and behavioral resemblances, and they are one of the most familiar wild animals to people in Japan. In order to know (1) the basic understanding / misunderstanding of students about Japanese macaques and (2) what kinds of facts are easy / difficult to understand merely by observation, I conducted a questionnaire survey about Japanese macaques for junior high school students visiting the Takasakiyama Natural Zoo. Four questions on Japanese macaques (tail length, female body mass, litter size and how to take foods) were asked of students who had observed macaques directly (group B) and those who had not (group A). For tail length and female body mass, the correct answer rates of group B were signi.cantly higher than those of group A, whereas the correct answer rates for litter size and how to take foods did not show a significant difference between the two groups. It is suggested that in conducting science education at monkey parks, educators should (1) investigate the basic knowledge of students on Japanese macaques and (2) design appropriate programs to introduce any facts according to the obviousness of these facts to students. This is especially so when introducing facts that cannot be visually demonstrated. In these instances educators must present scienti.c knowledge to students in inventive,"hands on"ways.

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Skewed artificial food allocation among a provisioned, free-ranging primate troop may encourage the desertion of low-ranking animals from the troop, such that deserters could become agricultural pests. Although differences in artificial food intake between dominance ranks have been investigated in some studies, those differences in feeding behavior that actually cause differences in food intake have been poorly documented. Differences in the feeding behavior for artificial foods between high- and low-ranking females were preliminarily investigated, between March and June, in provisioned, free-ranging Japanese macaques at Takasakiyama, Oita, Japan. At Takasakiyama, wheat grains and sweet potatoes are regularly given to macaques. As the small wheat grains take more time to handle than sweet potatoes, presumably, high-ranking macaques would be less easily able to monopolize it than sweet potatoes. Sweet potatoes are given to macaques once a day, whereas wheat grains are given several times a day at Takasakiyama. Notably, high-ranking females obtained 2.2 times more calories from artificial foods than did low-ranking females. Additionally, they acquired more calories from both food items than low-ranking females. High-ranking females gathered 71.5 to 104.9 % of the estimated amount of indispensable energy from artificial foods, whereas low-ranking females obtained only 21.2 to 45.0 %. Contrary to the prediction then, wheat grains impacted more on differences in calorie intake from artificial foods between high- and lowranking females than did sweet potatoes. This result indicates that the feeding policy requires modification, e.g. expanding the feeding area, increasing the ratio of sweet potatoes to wheat grains without changing the total calorific value given to each troop, etc., so as to allocate artificial foods more evenly among troop members.

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Chimpanzees are a naturally highly sociable species. Therefore, it is desirable to keep captive individuals in a social group. Although the dyadic introduction method has been commonly used to form social groups, it has not always been successful. In the present study, we tested a new method to create three all-male groups, two of which consisted of .ve individuals, and one of nine individuals. This method requires three stages. First, male dyads were put into neighboring cages in which the individuals could see each other. Tentative social rank was determined by observing the males' behaviors in these dyadic encounters. Next, they were moved to an unfamiliar environment and housed individually. Several days later, they were introduced one by one to an outside enclosure. Three allmale groups have been maintained so far, suggesting that group formation was successful. The occurrence of severe injury was considerably lower than that seen commonly in multi-male multi-female groups. Moreover, signi.cant effects of the group formation on male behavior (e.g., increased number of active social behaviors and decreased abnormal behaviors) were observed. These results demonstrate the effectiveness of our new method of forming all-male chimpanzee groups.

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