著者

岩本 光雄

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

vol.3, no.1, pp.59-67, 1987 (Released:2009-09-07)

著者

鵜殿 俊史 寺本 研 早坂 郁夫

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

vol.15, no.2, pp.243-250, 1999 (Released:2009-09-07)

参考文献数

15

被引用文献数

4 6 2

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The Kumamoto Primates Park, Sanwa Kagaku Kenkyusho CO., Ltd. had successfully bred chimpanzee from 1982 to 1999. The breeding statistics of 100 pregnancies, observed for the 17 years, were reviewed. The breeding females were 24 wild born and 3 captive born. Neonatal diagnoses were performed on the next day of the birth. Of 100 pregnancies, diagnosed by urinary CG test and/or ultrasonography, 11 resulted in abortions, 5 in stillbirths, and 85 in live births (containing a monozygotic twins). The mean birth weight and gestational period of 84 live born infants was 1793g (n=74, 930-2400) and 229.4 days (n=84, 181-250). Seven of 11 abortions occurred in early stage of pregnancies (45-65 days). Infant mortality in the first year of life was 10.7%: 6 died from 7 to 16 days of age, 3 died after 50 days of age. Three of dead 6 neonates were low birth weight (under 1500g). There was no infant died under 7 days of age or over 1 year of age. Perinatal mortality was calculated at 0.12. 73.2% of deliveries occurred in the nighttime (n=82). Placentaphagia were observed in 65.7% cases of 73 parturitions. The seasonal difference was significant on frequency of conceptions (χ2=10.16, p<0.02), but not significant on frequency of births (χ2=7.62, p>0.05). Twenty-nine infants were nursery-reared primarily due to inadequate maternal care (48%) or low birthweight (28%). Only one infant died under nursery-reared condition. These data provide useful information to sustain captive chimpanzee populations.

著者

岩本 光雄

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

vol.4, no.2, pp.134-144, 1988 (Released:2009-09-07)

被引用文献数

4 2

著者

半谷 吾郎

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.22, no.1, pp.43-49, 2006-06-20

被引用文献数

1

著者

岩本 光雄

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

vol.5, no.2, pp.129-141, 1989 (Released:2009-09-07)

被引用文献数

1 1

著者

松本 晶子

出版者

Primate Society of Japan

雑誌

霊長類研究 (ISSN:09124047)

巻号頁・発行日

vol.20, no.2, pp.165-166, 2004

著者

加藤 英子 南部 育志 小島 康生

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.15, no.1, pp.39-52, 1999-05-01

被引用文献数

1 2

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The social relationships of 10 young adult males in a free-ranging group of Japanese macaques at Katsuyama, Okayama Prefecture, were examined pre- and post-fission. Before group fission, higher-ranking young adult males interacted less frequently with not only their mothers, but also with other matrilineally-related females than did lower-ranking males. Six-year-old males clearly formed two subgroups according to their relative rank, even though they did not form any clear subgroups at the age of two.<br>Higher-ranking males spent more time away from females of the group than did lower-ranking males. However, when it was time for artificial feeding, higher-ranking males obtained scattered food more frequently than lower-ranking males. After group fission, four of the five higher-ranking males and one of the five lower-ranking males remained in the main group, while three of the five lower-ranking males were in the fission group.<br>These differences in the social relationships of young adult males might reflect the female subgroups which appeared prior to group fission.

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

---

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

川本 芳 川本 咲江 川合 静 白井 啓 吉田 淳久 萩原 光 白鳥 大祐 直井 洋司

出版者

一般社団法人 日本霊長類学会

雑誌

霊長類研究 (ISSN:09124047)

巻号頁・発行日

vol.23, no.2, pp.81-89, 2007-12-20 (Released:2009-03-13)

参考文献数

13

被引用文献数

6 7

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We examined a total of 20 blood samples for assessment of the degree of hybridization between introduced rhesus macaques and native Japanese macaques in the Bousou Peninsula. Each individual was characterized by different kinds of genetic markers (two protein loci, mtDNA and one Y chromosome DNA) in order to evaluate paternal and maternal origin and the degree of hybridization. The sample individuals contained one adult male Japanese macaque, and all others were rhesus or rhesus hybrid born in the study population. Of these 19 natal, at least 15 (78.9 per cent) were hybrids. The estimated frequencies of Japanese macaque genes were 0.342 and 0.857 for autosomal and Y chromosomal genes, respectively. This result revealed a high degree of hybridization in the introduced rhesus population. A test for random mating suggested that the two species were intermixing without reproductive defects. As the habitat of native Japanese macaque troops on the peninsula are very close, removal of the hybrid population is urgently required to prevent the transfer of their genes into the Japanese macaque population. It is also important to begin monitoring for further potential gene flow between rhesus and Japanese macaques in the peninsula.

著者

松沢 哲郎 ハムル タチアナ クープス カテリーナ ビロ ドラ 林 美里 ソウザ クローディア 水野 友有 加藤 朗野 山越 言 大橋 岳 杉山 幸丸 クールマ マカン

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.20, no.1, pp.45-55, 2004-06-30

被引用文献数

1 15

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The present paper reports the death of wild chimpanzees through a flu-like epidemic at Bossou, Guinea, West Africa. The community at Bossou has been studied continuously since 1976. Records from the past 28 years show that the number of chimpanzees in the Bossou community has been relatively stable, at around 20 individuals. In late November 2003, chimpanzees at Bossou began to cough. Within a month, five chimpanzees died: two very old females, one adolescent male, and two infants. The mothers of the two dead infants continued to carry the corpses, which eventually mummified. One mother used a stick to chase flies away from the dead infant's body in addition to using her hands. The transportation of infants' mummified bodies may be yet another example of cultural behavior unique to this community. A 12 year-old young mother, who lost her first offspring in this epidemic, remained with the community for two months following the death of the infant, after which she disappeared, most likely immigrating to a neighboring community. We inspected the year-by-year change of age-sex composition in the Bossou community. This revealed that the proportion of old members gradually increased while many young members immigrated. Such a gradual change in the population in addition to the epidemic suggests that this community is in serious danger. The paper also introduces our conservation efforts to attempt to save this important community: the "Green corridor project" which entails the planting of trees in the surrounding savanna in order to create a passage between Bossou and the Nimba Mountains, 4 km away. This might be a model case of connecting chimpanzee habitats that have become isolated through increasing human activity, a very common problem in West Africa.

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.

著者

山本 真也

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

vol.21, no.1, pp.19-26, 2005 (Released:2005-08-30)

参考文献数

25

被引用文献数

2 3

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The present study investigated vigilance in Japanese macaques (Macaca fuscata) in reference to some social factors. Previous studies have suggested that social factors among conspecifics should be important for vigilance in primates. This study explored the relationship between individual's social rank and vigilance in estrous and non-estrous periods in female Japanese macaques. With a video camera, I recorded vigilance of 23 females among approximately 170 individuals of Arashiyama E-troop. The results were as follows. High degree of vigilance was observed in three conditions, 1)females in estrous period regardless of the rank, 2)low-ranking females in nonestrous period, and 3)females in estrous period consorting with low-ranking males. These results indicate that social relationship is an important factor which affects the degree of vigilance in female Japanese macaques.