著者
井上 美穂
出版者
Primate Society of Japan
雑誌
霊長類研究 (ISSN:09124047)
巻号頁・発行日
vol.3, no.2, pp.103-111, 1987 (Released:2009-09-07)
参考文献数
13
被引用文献数
16 14

Soil-eating (geophagy) behaviors of Japanese macaques were observed at Arashiyama Monkey Park, Kyoto. They eat soils about once a day or so and seem to prefer rather young soils to mature or senile soils. The soil samples for chemical analysis were collected from Arashiyama, as well as from Takasakiyama and Kohshima monkey parks. Their pH, electrical conductivity, cation exchange capacity, organic matter, inorganic phosphorus and extractable minerals, i. e. calcium, magnesium, sodium, potassium and iron contents were measured. Mineral contents of the soil samples are low and the differences in their values among samples at eating spots and those at non-eating spots in the same monkey park are not detected. Moreover, the differences among monkey parks exceed those between eating and non-eating soil samples.Japanese macaques often eat soils together with another individuals. In such co-eating episodes, intimate individuals, such as a mother and her infant, or two or more juveniles of the same age often form co-eating party. It is expected that Japanese macaques eat soils at the selected spots because of their co-feeding custom and that the supply of minerals such as calcium, magnesium and sodium is not so seriously important, although the possibility of intake of essential rare minerals is not ruled out.
著者
半沢 真帆
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
pp.36.015, (Released:2020-11-30)
参考文献数
54
被引用文献数
2

Direct observations of the behavior of wild Japanese macaques (Macaca fuscata) in many populations have been recorded over the decades. However, novel behaviors continue to be reported. Here, I report a novel social behavior “rump-rump contact” among males of one group in Yakushima, a behavior that has not been reported in any macaque species. Eight cases of this behavior were observed in 87 observation-days between August and October 2018. They were classified into two types: the RR type, where the rumps of the two individuals symmetrically touched each other, and the RT type, where the rump of one individual was in touch with the lateral torso of the other. At the same time as this behavior, the two individuals clasped the other's body and touched the other's hindquarter by wagging tails. The contexts in which this behavior was observed suggests that it helps in regulating social tension, as might be the case in bonobos where the RR type is known. However, it is likely that this behavior in the two species is not entirely comparable, as no genital contacts with thrust was observed in the Japanese macaques as part of this behavior. In the macaque, it is possible that this behavior was derived from “presenting” because it was seen just before this behavior, and the same action of clasping the other's body was seen at the same time as this behavior. This is a highly novel behavior in that, wagging tails may be a kind of tactile communication, which has never been reported in nonhuman primates. Additionally, it is valuable that this behavior previously known only in bonobos and chimpanzees was also observed in the Japanese macaques, which have very different phylogenetic relationships and social systems. Further studies may reveal the affinitive relationships that goes beyond the strict dominance relationship between males.
著者
山崎 彩夏 武田 庄平 鳥居 映太 鈴木 創三 清水 美香 黒鳥 英俊
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.26, no.1, pp.59-66, 2010-06-20 (Released:2010-07-01)
参考文献数
11
被引用文献数
2 2

Geophagy (soil-eating) is one of the well-known behaviours in many primate species, but the factors influencing this behaviour have been less known. In the captive environment of Tama Zoological Park, 2 female Borneo orangutans (Pongo pygmaeus) showed geophagic behaviour that was restricted to a particular site in the naturalistic outdoor enclosure. We compared the properties of the soil at this site with those of soils from 7 other different sites in the enclosure to determine the differences between the soils. To this end, we examined the landform, vegetation type, the physical and chemical characteristics of the soils at these sites. The enclosure was situated on the hillside of secondary woodland comprising Fagaceae sp. with a gently sloping ridge on the east side and valley bottoms on the west side. The site at which the animals exhibited geophagic behaviour was located at the lowest area of the valley bottoms. We found that this area was thinly covered by a herbaceous layer with Gramineae sp., and most of ground surface was bare. The soil eaten by orangutans had a low density and was highly friable, soft, and wet. Chemical analysis revealed that the soil in the enclosure had a high Ca content (70-80%) and that soils at some points in the enclosure, including the soil at the site of geophagic behaviour, had high Fe and Mg contents. The site of geophagic behaviour was located at the bottom of the valley; therefore, soil ingredients may have accumulated easily in this soil. However, we could not find any definitive chemical factors to explain the geophagic behaviour of orangutans. One possible explanation is that since the site was bare with highly friable, soft, and wet soil, the orangutans would have been able to easily eat the soil from that site.
著者
橋本 千絵
出版者
Primate Society of Japan
雑誌
霊長類研究 (ISSN:09124047)
巻号頁・発行日
vol.10, no.3, pp.261-267, 1994 (Released:2009-09-07)
参考文献数
17

Immature bonobos genital contact behavior with individuals of most age classes. Genital contact between immature individuals was most frequently performed in the ventro-ventral posture. It was usually observed during play sessions, and males participated more frequently than females. Both males and females perform genital contact with adult males though not so frequently. On the other hand, only males frequently perform genital contact with adult females and its frequency increased with age. As they grew older, genital contact behavior of immature males with adult females became more like copulation between adults. By contrast, immature females did not have any genital contact behavior that resembled copulation. Females became very active in copulation with adult males and genital contact behavior with adult females after they had moved to non-natal groups.
著者
上野 将敬
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.34.002, (Released:2018-06-27)
参考文献数
75

Group-living primates often perform complex social behaviors. Traditionally, observational and experimental studies have provided important insights into the social behaviors of primates; however, these studies have limitations regarding unambiguous causality. The use of artificial stimuli can aid in understanding the mechanisms of animal behavior. A robot, which can perform some behavior sequences automatically or by remote control, serves as a new method to study the response of an animal to the stimulus of the same or other species. One of the advantages of using a robot is that researchers can change the appearance and behavior in line with their purpose. In addition, using a robot can help investigate the influence of more than one individual on another individual's behaviors. Although it is advantageous to use robots in the study of animal behaviors, it entails various challenges. This paper reviews the studies on animal behavior that used robots as stimuli and discusses the contribution of using robots in primate behavior study in the future.
著者
平松 千尋
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.26, no.2, pp.85-98, 2010-12-20 (Released:2011-02-01)
参考文献数
65
被引用文献数
4 1

Primates are unique among placental mammals in having trichromatic color vision, while most mammals possess dichromatic color vision. It has been hypothesized that the adaptive significance of trichromacy in primates is to detect reddish ripe fruits against a dappled foliage background. However, a behavioral advantage of trichromacy for fruit foraging has not been demonstrated in wild populations. The present paper reviews color vision status and utility of color vision in various primate species and describes recent advances in examining the significance of trichromacy. New World monkeys, which express high intraspecific color vision diversity due to an allelic polymorphism of the X-linked opsin gene, provide the excellent model to explore the significance of trichromacy for frugivory. The comparison of fruit foraging efficiency between dichromatic and trichromatic individuals in free-ranging black-handed spider monkeys (Ateles geoffroyi) inhabiting a Costa Rican dry forest did not reveal any trichromat advantage. This result is explained via the luminance contrast between fruits and background leaves, which cues the detection and selection of edible ripe fruits when fruits are viewed from close distances. In addition, sniffing behavior toward fruits was negatively correlated with luminance and blue-yellow contrasts, suggesting that monkeys use olfactory cues when vision alone is insufficient to select edible fruits. These results suggest that an advantage of trichromacy is not salient under natural conditions where many sensory cues are available. To understand the significance of trichromacy, it is necessary to evaluate how trichromacy benefits fruit detection over long distances. It is also important to observe various social feeding behaviors to examine alternate hypotheses, such as mutual benefit of association.
著者
辻 大和
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.28, no.2, pp.109-126, 2012-12-20 (Released:2013-01-24)
参考文献数
130
被引用文献数
4 4

In this review I introduce the literature concerning variations in the feeding ecology of wild Japanese macaques (Macaca fuscata), for which many Japanese primatologists have collected data for more than 60 years. Specifically, I review 1) temporal, 2) spatial, and 3) inter-individual variations in the feeding ecology of the macaques. Food resources of the macaques in habitats exhibit temporal shifts (in short-term, seasonal change, and inter-annual change), which consequently affect feeding-related behavior, such as ranging patterns, activity budgets, and degree of crop-raiding. On the other hand, temporal changes in feeding sometimes affect inter-specific relationships. Food environment differs regionally, which is attributed to forest productivity and flora, and/or physical conditions such as temperature and snowfall. The feeding ecology differs even between neighboring troops inhabiting different forest structures. A troop of macaques consists of males and females of different ages and social ranks whose nutritional demands vary. Such inter-individual variation within group affects their feeding ecology, which consequently affects population parameters through competition over food resources. Variation in food habits would affect other ecological phenomena, such as seed dispersal and plant community structure. Finally, I discuss several challenges facing future studies of the feeding ecology of Japanese macaques.
著者
杉山 幸丸
出版者
Primate Society of Japan
雑誌
霊長類研究 (ISSN:09124047)
巻号頁・発行日
vol.18, no.1, pp.19-33, 2002 (Released:2009-09-07)
参考文献数
62

Individual dispersal is seen throughout the biological world. The present article discusses the dispersing sex of chimpanzees and humans with special reference to their common ancestors from the point of view of their biological characters, which are basically common with other mammalian species, concerning gestation, parturition, lactation and nursing. Many mammalian species have male-dispersal and female-philopatric (or short-distance dispersal) societies. However, chimpanzees are said to have male-philopatric and female-dispersal societies. Comparing with those of Bossou, Guinea, where males as well as females during adolescence may disperse, I hypothesized that male chimpanzees of other research fields allow each other in a group and form ‘male-bond’ to defend their resources from conspecific competitors and predators. The necessity for hunting cooperation may be a subsidiary factor. However, the problem why non-related males cannot be accepted and all related males cooperate with each other in their natal group remains to be solved. On the other hand female dispersal is not unusual among mammals in a habitat having few predators. However, the problem why young pregnant females and mothers with dependent infants transfer to an adjacent group in spite of the possibility of receiving infanticide also remains to be solved. Many scholars hypothesize that common ancestor of chimpanzees and humans also had a male-philopatric and female-dispersal society just as most present day human societies have. However, the transfer of a human female to a distant community or region does not depend on her own decision but that of her parents in exchange for treasure or for political purposes. Instead of a rigid sex-biased dispersal society I hypothesized the existence of a fluent and flexible bilateral society as our common ancestors.
著者
上野 将敬
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.33, no.1, pp.21-34, 2017-06-20 (Released:2017-07-27)
参考文献数
105

Group-living primates are likely to spend a substantial amount of time grooming and resting with a small number of other group members. Such close and enduring relationships are regarded as affiliative. The properties of affiliative relationships are not fully understood and no consensus exists on how to quantitatively describe them. In this review, I explain the primate behaviors that are related to affiliative relationships and examine the means for using these behaviors to measure the relationship. Traditionally, affiliative relationships are defined by the frequency of proximity and grooming. Individuals with frequent proximity and grooming tend to perform altruistic behaviors for their partners without immediate return from them, groom each other in a reciprocal manner in the long-term, show distress and reconcile after agonistic interactions, and synchronize their behaviors with those of their partners. Thus, in addition to measuring the frequencies of proximity and grooming, these behavioral tendencies might be used as indices of affiliative relationships. Similarly, other questions concerning affiliative relationships remain unexplained. Some studies show that affiliative relationships increase reproductive success, but the mechanisms leading to fitness outcomes remain unclear. Although typically in primates, related individuals tend to form affiliative relationships, such relationships are also formed with unrelated individuals. Affiliative relationships could mitigate the negative effects of competition among individuals in large social groups and ensure that the individuals that form the relationship receive benefits from each other (e.g., agonistic support and collective mobbing). It is also unclear whether the affiliated relationships of nonhuman primates are equivalent to those of humans. Further research is necessary to elucidate similarities or differences in affiliative relationships between human and nonhuman primates.
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.27, no.2, pp.95-109, 2011-12-20 (Released:2012-01-19)
参考文献数
68
被引用文献数
2 1

How did humans evolve to such an altruistic and cooperative animal? This review paper discusses the primate origin of altruism and cooperation from the viewpoints of cognitive mechanisms and adaptation to social systems. Our previous studies have revealed three characteristics of chimpanzees' altruistic helping behavior: 1) helping upon request, but seldom voluntarily; 2) understanding others' goals by visually assessing the situations; and 3) understanding of others' goals does not automatically lead to voluntary helping. It is suggested that the mechanism in chimpanzees' helping is different from that in human helping, which is often solicited by only witnessing others in trouble. This difference in spontaneity in helping might be a result of their different social systems. In human societies, where indirect reciprocity works, individuals who behave altruistically can gain good reputations. In such societies, voluntary helping is favored and rewarded. Meanwhile, institutions and social sanctions exist in human societies: selfish individuals can be punished by third-party group members. This system also maintains altruism and cooperation. In contrast, there has been no empirical evidence for existence of reputation and social sanction in chimpanzees, which might explain their lack of voluntary helping. Instead of indirect reciprocity, fission-fusion dynamics might be an alternative system for maintaining altruism and cooperation in chimpanzee societies. It is possible that an ecological environment influences a social system, which in turn determines behavior and its mechanism. This emphasizes the importance of empirical studies with broad perspectives. Comparative studies with humans, chimpanzees and bonobos both in the wild and under experimental conditions are expected to deepen our understanding of the evolution of altruism and cooperation, and accordingly to reveal multiple dimensions of human evolution from the viewpoints of cognition, behavior, society, and ecology.
著者
船橋 新太郎
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.22, no.2, pp.85-96, 2006 (Released:2007-03-13)
参考文献数
38

ADHD is one of the most prevalent childhood psychiatric disorders and could be explained as a prefrontal dysfunction. Studies suggest that ADHD is related to deficits of dopamine-related functions, because methylphenidate, which is a dopamine transporter inhibitor, is the most effective medication for the treatment of ADHD. The prefrontal cortex is the cortical area where the most strong dopamine innervation is observed. Local acute injection of dopamine-related drugs to the prefrontal cortex produces modulation of task-related activity and behavioral deficits in cognitive task performances. Thus, the dysfunction of dopamine-related modulation in the prefrontal cortex could be a possible candidate of biological causes of ADHD. To prove this idea, in the future we are going to inject 6-OHDA into infant monkeys' prefrontal cortex to disturb dopamine functions chronically and compare its behavior with normal monkeys.