著者
竹元 博幸
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.34, no.1, pp.87-102, 2018 (Released:2018-08-22)
参考文献数
75

The origin of bonobos and the history of their dispersion in the southern Congo Basin were investigated from the perspectives of biogeography and the paleo-environment. Why bonobos are distributed in the southern Congo Basin was unclear because of limited geological records about the region and genetic information for bonobos. Recently, colleagues and I proposed some hypotheses concerning the history of bonobos based on recent reports about marine sediments and structural geology of the Congo basin, as well as new mitochondrial DNA haplotypes collected from seven wild bonobo populations. Here, I illustrate these hypotheses, namely: 1) the Congo River functioned as a biogeographical barrier for forest animals since 34 million years ago; 2) the ancestor of present bonobo populations crossed the upper parts of the Congo River from the right bank to the left bank during the early Quaternary period; and, 3) factors affecting the genetic structure of present bonobos. Lastly, I propose possible future studies to investigate bonobo evolution.
著者
藤田 和生 黒島 妃香 服部 裕子 高橋 真 森本 陽 瀧本 彩加 佐藤 義明
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.24, no.3, pp.241-263, 2009-03-31 (Released:2010-06-17)
参考文献数
85
被引用文献数
2 1

Capuchin monkeys are one of the most important primate subjects in understanding the evolution of kokoro (mind and heart), because of their outstanding intelligence and gentleness despite their phylogenetic distance from humans and apes. Here we report a series of experimental studies on various aspects of the kokoro of tufted capuchin monkeys (Cebus apella) conducted at the comparative cognition laboratory, Graduate School of Letters, Kyoto University. Briefly, for the physical intelligence, the monkeys amodally completed partly occluded figures basically like humans do. They also perceived never-presented contours by spatially and temporally integrating a sequence of fragmentary information just like humans do. They understood physical causality in a type of tool-use task involving tool, goal, and environment. In the social intelligence domain, they spontaneously took actions interpretable as tactically deceiving the conspecific opponent in an experimental food-competition contest. They also cooperated by dividing a sequence of actions leading to rewards. This cooperation continued when only one of the participants obtained a reward at a time. They were sensitive to attentional states of humans shown by eyes, though they might not try to control human attentional focus. They inferred a conspecific's behavior that they never directly observed and adaptively modified their next behavior based on the predicted consequence. They were also able to correct their actions by observing unsuccessful actions of their conspecific partner. One monkey of this species showed evidence that she recognized the knowledge status of humans suggested by their preceding actions toward the items in question. In the affective domain, this species was shown to utilize affective reactions of a conspecific against a hidden object to regulate their own actions toward it. Finally, the monkeys were sensitive to the benefit of their conspecific partner. They sometimes took thoughtful actions toward a low-ranking individual and in other times spiteful actions against a high-ranking individual. All of these results show that this New World species shares many characteristics of kokoro observed in humans.
著者
國松 豊
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.19, no.1, pp.65-85, 2003 (Released:2005-03-24)
参考文献数
94
被引用文献数
2 1

The extant hylobatids are relatively small primates, and often called lesser apes. The body weight is 5-8 kg for the majority of the hylobatid species, and 10-12 kg for the largest species, Hylobates syndactylus. Recent taxonomy classifies the hylobatids into a single genus Hylobates with four subgenera (Hylobates, Nomascus, Bunopithecus, & Symphalangus) (Groves, 2001).The present geographical distributions of the subgenera are almost perfectly bordered by three (or possibly four) huge rivers in Eastern Eurasia, that is, the Brahmaputra, Salween, Mekong (and Yangtze) Rivers. All these rivers originate from the Tibetan Plateau. Although van Gulik (1967) reconstructed the historical distribution of gibbons in China as being expanded northwards over the Yangtze River up to the Yellow River, the Pleistocene fossil evidence suggests that the northern limit of the gibbon distribution in China was probably the Yangtze River.Recent genetic studies suggest that these subgenera began to diversify around several to ten million years ago. In this period, the Tibetan Plateau reached a considerable altitude. The uplift of the Plateau probably influenced the development of the above mentioned huge rivers, strengthening the function of these rivers as zoogeographical barriers. It seems likely that the proto-hylobatid populations were then isolated from each other, and evolved into recent subgenera, though the diversification between the subgenera Hylobates and Symphalangus needs another explanation.At present, the fossil record of the hylobatids is very poor. There are some Pleistocene gibbon fossils discovered from southern China and Southeast Asia, but no Neogene fossil catarrhines, small or large, are thought to be the direct ancestor of extant gibbons. In Southeast Asian countries, except for a few findings such as the Chiang Muan hominoids discovered from Thailand by the Thai and Japanese scientists, we know nothing about the Neogene fossils of both large and small hominoids. No doubt further field works are necessary to reveal the evolutionary history of gibbons.
著者
辻 大和 和田 一雄 渡邊 邦夫
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.27, no.1, pp.27-49, 2011-06-20 (Released:2011-07-28)
参考文献数
258
被引用文献数
7 11
著者
布施 未恵子
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.29, no.2, pp.105-121, 2013-12-20 (Released:2014-02-28)
参考文献数
79
被引用文献数
2 2

Most primates forage on insects to varying degrees. Research focusing on insect foraging behavior has been much less than that of feeding on plant foods. However, detailed studies on insect feeding behavior by primates are required to understand the effects of the relationship on the forest ecosystem. Such studies have revealed that various kinds of primates feed on insects, but the number of studies which have considered side effects of primate-insect relationships have been few. Such triadic relationships include 1) primate-insect-plant, and 2) primateinsect-parasite. Studies based on such viewpoints would lead to new perspective on the role of primate insectivory in forest ecosystems.
著者
佐藤 宏樹
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.33, no.1, pp.3-20, 2017-06-20 (Released:2017-07-27)
参考文献数
141

Traditionally, the activity patterns of primates have been classified as nocturnal and diurnal, with the former recognized as the ancestral trait. Since cathemerality, i.e., active both day and night, was discovered in Eulemur (Lemuridae) in the 1960s, the evolutionary origin and mechanism of cathemerality have been explored as a key to understanding diurnalization in primates. To understand cathemerality in lemurs, this article reviews current knowledge and outlines future issues. Although several theories have hypothesized that cathemerality is an evolutionary disequilibrium condition, as a consequence of recent, incomplete diurnalization, the current analyses of phylogenetic history and eye morphology conclude that it is an adaptive strategy that originated in the common ancestor of Lemuridae around 46-20 MYA. In Madagascar, the days are generally long during the rainy season and short during the dry season. Cathemeral lemurs often increase their diurnal activities in the rainy season and nocturnal activities in the dry season. Chronobiological approaches that have explored the proximate mechanisms have clarified that the light-dark cycle controls the daily activity rhythms and the day-length cause seasonal shift of activity patterns as zeitgebers. In addition, moonlight has a masking effect that facilitates nocturnal activities. Ecological/ethological approaches have examined four hypotheses, as ultimate mechanisms: avoidance of predation risk, relief of interspecific competition, thermoregulation, and extension of feeding activities. However, there is evidence supporting and countering all four hypotheses. Therefore, cathemerality cannot be defined as an adaptive consequence of any single factor. Consequently, cathemerality is recognized as a flexible strategy for dealing with several factors in the harsh, unpredictable Madagascar environment. In the future, researchers need to examine flexible activities in response to other factors, such as habitat disturbance caused by humans, to explain complex mechanisms caused by compound factors, and to compare the activities of diurnal lemurs using ecological and physiological approaches.
著者
木下 こづえ
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.34, no.1, pp.5-15, 2018-06-20 (Released:2018-08-22)
参考文献数
96
被引用文献数
4

The animal is connected to the external environment (e.g., social environment, habitat environment) via their brain, and the hormone plays an important role as its transmitter substance. In other words, when the external environment changes, hormones are secreted to adjust the internal environment in response. Therefore, hormone analysis is a useful tool that enables researchers to know animal's physiological state under various environments.Since the measurement of hormone concentration can be carried out at a relatively low cost and does not require advanced technique, it is applied to a wide research field. For example, many relations between behaviors and hormones were clarified, such as behaviors in estrus and rut, infant rearing, attacking behaviors, intra/inter-species communications, and response to the change of habitat environment. Recently noninvasive samples are often used for the hormone analysis in both captive and wild animals (e.g., urine, feces, and hair). However, when excrement is used as a sample, it should be noted that there is a species specificity in the excretion route of hormones and the time taken for excretion. Also, depending on hormones, it is necessary to thoroughly examine the sampling frequency according to the change of hormonal concentration. As Beach (1948) summarized, no behavior depends only on one type of hormone, and conversely, no hormone has only one kind of physiological function. Not one but multiple mechanisms are involved in the hormonal control of behavior. Therefore, focusing on multiple hormones and evaluating results from various aspects are also important keys to capturing their invisible physiological state accurately.
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

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.