著者

中川 尚史 中道 正之 山田 一憲

出版者

日本霊長類学会

雑誌

霊長類研究 (ISSN:09124047)

巻号頁・発行日

pp.1111280025, (Released:2011-11-30)

参考文献数

29

被引用文献数

4 7

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Questionnaire on infrequently-observed behaviors (IOBs) in Japanese macaques (Macaca fuscata) were given to primatologists. This survey aimed to provide basic information on the degree of rarity of each behavior. The questionnaire consisted of questions for respondents themselves, (e.g., name, research carrier, daily observation time), focal group (name of group and local population, captive, provisioned free-ranging, crop-raiding or purely wild), and IOBs. Experience of direct observation of 36 candidates of IOBs was also requested to answer by yes, no, or impossible to answer because of ambiguous memory or unawareness of its behavior. In total, 39 answer sheets were obtained from 32 respondents. The top 10 IOBs and the number of those answering "yes" in parenthesis are as follows: mating interruption by juveniles (1), simultaneously nursing different-aged offspring (1), tool-use (1), single mount ejaculation (2), transporting the older offspring (2), nursing the older offspring (2), simultaneously transporting different-aged offspring (3), pulling the hair of female chin as a courtship behavior by male (4), twin birth (4), and (diurnal) birth (6). Some of IOBs, such as mating interruption by juveniles, seem to be due to ambiguous memory or unawareness of its behavior. Apparent inter-population differences in the percentage of respondents answering "yes" to the all the respondents giving definite answers were found in some behaviors, such as embrace-rocking behaviors, mating behaviors in birth season, stone-handling, and feeding on vertebrates. Some of them, like the latter two, seem to have something to do with provisioning. With the modification of three categories by Nakamichi et al. (2009), we proposed the following five categories of IOBs: I) behaviors which are difficult to be observed despite its common occurrence; II) behaviors which rarely occur in every population: III) behaviors which rarely occur in some populations, but frequently occur in the others; IV) behaviors which are difficult to identify and memorize despite its common occurrence; V) behaviors which rarely occur during the most of the time but temporally occur.

著者

中川 尚史

出版者

日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.46, no.3, pp.291-307, 1996-04-25

被引用文献数

9

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Studies on food selection in non-human primates were reviewed from the viewpoint of optimal food selection. Key factors in the classical model of optimal food selection were "maximization" of the "intake rate" of "energy". Later, the key factors were changed to "maximization" of the "contents" of "energy-essential nutrients" and "minimization" of the "contents" of "digestion inhibitor-toxins" in a modified model for herbivores. Most studies on food selection in herbivorous non-human primates have been based on the modified model, and revealed that primates choose food so as to maximize protein, and to minimize digestion inhibitiors (fiber, condensed tannin). However, the present review points out that the above key factors of the classical model are also important because food availability relating these factors correlates positively with feeding frequency.

著者

中川 尚史

出版者

Primate Society of Japan

雑誌

霊長類研究 = Primate research (ISSN:09124047)

巻号頁・発行日

vol.24, no.2, pp.91-107, 2008-12-20

被引用文献数

3 3

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The male-female affinitive relationships among non-kin which persist beyond the estrus period have been known in some primates, mainly savanna baboons, Japanese macaques and rhesus macaques. I call this friendship, and review the benefits of friendships for each sex. For females, proximity and alliance of male friends disrupts antagonism by opponents, more or less, in all three species. On the other hand for the males, the effect of enhanced reproductive success seems to be negative. It is necessary to fully consider male benefits via infants in savanna baboons. Since it is highly possible that baboon males take care of a female friend's infant that he sired in the past, such friendships, especially in infanticidal baboons, would evolve through kin-selection rather than reciprocal altruism. When it comes to reciprocal exchange of benefits between a male and female, it seems that females play a positive role in the maintenance of friendships, as overall benefits seem to be female-biased. Socio-ecology can offer explanations for the ultimate cause of friendships. However, its explanatory power is not enough to explain the following observations: two non-troop males visit a group of Japanese macaques in coastal forest, Yakushima on separate days during a mating season. They received grooming one-sidedly by a female and soon left the group without copulating. These two cases seemed to be interactions between old friends, but the reciprocity cannot be formed. As the reunion with an old female friend of a male after immigration rarely occurs, mal-adaptive behavior would not be a problem. Socio-ecology does not explain such rarely occurring events. However, we can not ignore such cases just because they rarely happen. It is one aspect of the Japanese macaque society that monkeys "renews" old friendship.