Nearly 60 primate species consume fungi as a part of their diet, where some species are heavily dependent on fungi, while others use them as minor food resources. Three methods have been used to study mycophagy (fungus-eating behavior) among primates: stomach content analysis, direct observation, and fecal analysis. Direct observation is the most widely used but provides only limited information regarding fungi species eaten by animals. DNA analysis or stable isotope analysis can complement such behavioral data to reveal new insights into mycophagy. Fungi play an important role in maintaining healthy forest by forming mycorrhiza with plant species. Mycophagous primates disperse fugal spores therefore might also contribute to the forest ecosystems. Regardless of their potential as spore dispersers, far fewer studies focus on primates compared with those on other mycophagous mammals such as rodents and marsupials. Studies show that primates generally consume above-ground fungi, while rodents and marsupials use subterranean truffles. Considering the facts that some terrestrial fungi are highly poisonous and that primates build a food repertoire based on feeding experiences, we are confronted with a question of whether they learn how to avoid poisonous fungi. New perspectives and approaches will allow us to explore the animal-fungus relationship in the ecosystem.

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Parasites are ubiquitous in nature and can have profound impacts on host populations. Primates are among the most threatened animals in the world, yet our understanding of the baseline epidemiological factors that naturally contribute to infection dynamics, and thus our ability to predict specific disease outcomes, remains poor. In this invited review, I argue for the necessity of good empirical model systems through which just such an understanding can be approached. I highlight the utility of one such model system that is both parsimonious and highly accessible: the Japanese macaque and its gastrointestinal nematode parasites as a single-host, multi-parasite study system. I explore epidemiological patterns of nematode infection in Japanese macaques and re-introduce the concept of parasite aggregation in an attempt to re-frame current understanding of, as well as re-direct future questions about, primate-parasite interactions as host and parasite population processes. Despite the fact that parasite aggregation has critical implications for understanding the processes involved in both host and parasite regulation, including the various cascading ecological effects regulation can have, this approach is seldom used in studies of primate parasite ecology. Ultimately, this review aims to remind us that parasitism is fundamentally an ecological interaction and that, like predation and competition, parasites play important roles in mediating ecosystem health, including the various functional roles that primates may fulfil.

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In tropical forest ecosystems, majority of plant species depend on frugivorous vertebrates for seed dispersal. Because primates constitute a large portion of frugivore biomass in neotropical and paleotropical forests, the roles of primates as seed dispersers have been examined since 1970's. The process of seed dispersal by vertebrates can be divided into three phases: (1) pre-dispersal phase in which animals select particular fruits as attractive food; (2) dispersal phase in which animals handle, transport, and deposit seeds during their foraging activities; (3) post-dispersal phase in which dispersed seeds germinate and grow to reproductive age. To understand roles of primates as seed dispersers, this paper marshals the previous achievements in order of the three phases. During pre-dispersal and dispersal phases, quantitative and qualitative effectiveness of seed dispersal are generally related to several anatomical traits and behavioral pattern of each primate taxon, and particularly, large-bodied frugivorous primates often perform effectively. However, during post-dispersal phase, high mortality and unpredictable fates of dispersed seeds dramatically hurt the effectiveness of primate seed dispersal. Large-bodied frugivorous primates are recognized as vulnerable taxa to human disturbance such as deforestation and bushmeat hunting. Recently, in the forests where such primates are locally extinct or reduced, researchers have demonstrated that the loss of their seed dispersal services drives low density of seedlings and saplings and low rates of gene flow among populations. These facts paradoxically suggest that primates contribute regeneration of plant populations even their effectiveness is lessened in post-dispersal phase. As future issues, integration between seed dispersal research and plant demographic study will develop our understanding of the primates' roles in plant population dynamics over many generations. Moreover, considering the critical situations in empty forests, there is also an urgent need to argue prioritized conservation of high-performance primates for maintaining regeneration and vegetative restoration in degraded forests.

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Primates are diverse regarding morphologically and ecologically. They play significant roles in the various niches of the ecosystem. In relation to the effects on the fitness, there are six possible combinations of biological interaction between primates and other species, ranging from harmful to mutually beneficial interactions and neutral interactions, such as predator-prey interaction (i.e., herbivory, predation and parasitism), competition, amensalism, mutualism, commensalism and neutralism, which result in the diverse species interactions. Therefore biological interactions between primates and other species have been studied. There are two major advantages in the ecological research of primates. Firstly, researchers are able to clarify detailed individual behaviours and ecological processes through the direct observation of primate individuals. Secondly, researchers are able to follow the secular trends of individual growth and/or lineages of blood relations through the long-term research of identified primate troops. We need further researches in the primate-other species interaction by applying field experiments, systematic background data, research networks, new research technology, meta-analysis methods, and transdisciplinary idea.

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Drawing upon a large body of literature comprising various applications of fractal theory and complexity science in ecology and evolution, I illustrate that animal behavior can be characterized usefully by its fundamentally fractal nature in both time and space. I begin with an introduction to fractal geometry and then provide examples of how and why its analysis has been employed in biological/ecological studies. I examine the three main approaches used to model animal behavior through the fractal lens, and show how (i) the Lévy flight foraging hypothesis, (ii) spatial fractal dimension estimates and (iii) fractal time have each complemented more traditional investigations of animal behavior and provided unique insights into ecological processes. I then focus on illustrating how fractal analysis can be used as a sensitive indicator of behavioral or environmental 'quality'. I argue that complex behavior sequences both result from and are necessary to cope with environmental heterogeneity. This body of work supports the hypotheses that complexity is biologically adaptive and that complexity loss, i.e. greater periodicity or stereotypy, is not only indicative of altered or impaired condition but may in addition carry with it significant fitness consequences. Throughout this essay, I attempt to emphasize that by extending beyond our traditional disciplinary boundaries, behavioral ecologists stand to gain unprecedented insight into complex phenomena in the lives and activities of organisms all around us. It is my sincere hope that the ideas presented herein encourage future interdisciplinary research into the role of complexity in behavioral organization, and what that might mean for ecological processes.

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Since language is basically audio-vocal communications in humans, the vocal communication in nonhuman primates has been discussed with the questions for evolutionary origins of languages. Many studies have accumulated many empirical evidences showing similarities as well as gaps between human languages and nonhuman primate vocal communications. Here I briefly reviewed the research history of the studies for vocal communications in nonhuman primates, which have been mainly directed to search for origins of human languages. Generally, there are two major approaches for primate origins of human languages; 1) studies of vocal communication in nonhuman primates would contribute to understanding the origins of languages, or 2) it would be completely different forms of language and never contribute to its understanding. The first brief is arisen from the ethological studies for alarm calls, using playback experiments in wild animals. Those studies have showed semantic rules in their communications, which had been believed as a unique component of human language. However, their anatomical and physiological foundations never support vocal plasticity and learning ability in nonhuman primates, which are essential properties in human languages. Those usually lead to the second brief. It would be difficult to solve this critical discrepancy, because both ideas likely discuss the origins of languages with wrong views of unidirectional way in language evolution, i.e., the way from nonhuman primates to humans. Human languages is not the most complex fashion of vocal communications in primate lineages, but vocal communications in other primate species are also complex and unique styles. Now we need more careful attentions to communication uniqueness of various kinds of primate species as well as language uniquness.

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Using long-term behavioral data recorded between1950 and 2010, we studied cases of change in the alpha individual and its social background in a captive troop of Japanese macaques (Macaca fuscata) housed in Ueno Zoological Gardens, Tokyo, Japan. During this period, nine alpha males and four alpha females were recorded. Among the alpha males, three were juveniles. All alpha males except for one continued to keep their position until they died or were removed from the group. Alpha females, on the other hand, lost their position when they were in estrus/pregnant/nursing, after which time they continued to stay in the group. Unlike cases in free-ranging populations, captive male Japanese macaques are included in the social hierarchy of their natal group, and dominance relationship between males and females were unclear. Under such conditions, dominant females and their juveniles can become alpha individual when the former alpha disappears and/or there are no dominant male(s) present. Appearance of female/juvenile alpha individuals in the Ueno Zoo troop seems to be one of the bi-products of a captive environment and in order to keep social relationships of captive animals similar to those of free-ranging populations, artificial transfer (removal/introduction) of adult males should be considered.

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Chimpanzees were first kept in captivity in Japan in 1926. The Great Ape Information Network (GAIN) collated historical and current data on all chimpanzees housed in Japan between 1926 and 2013 (972 individuals). GAIN has made this information available on an open-access database, with a record for each chimpanzee. Aims of this resource are to promote and inform good scientific research, welfare, care, and management of captive chimpanzees in Japan. This review presents quantitative data on the number of chimpanzees housed in each facility-type, number of individuals per facility, and increases in the number of individuals (imported historically or born in Japan). Facilities were categorized according to purpose: 1) zoo exhibition and/or entertainment, 2) cognitive/behavioral studies, 3) biomedical, and 4) other (animal dealer or privately-owned as pets). By the 1970s, chimpanzees housed in captivity increased with the number of zoos. Many wild chimpanzees were imported from Africa for use in invasive biomedical studies in around 1980. Japan ratified CITES in 1980. The captive population peaked in the 1990s, before decreasing. Field studies and laboratory-based cognitive investigations of chimpanzees in the 1990s and 2000s swayed public opinion against biomedical use. In 2006, invasive study of chimpanzees in Japan was severely limited and, by mid-2012, completely stopped. Ex-biomedical chimpanzees were assigned to cognitive and welfare studies. Since the 1987 peak in number of facilities, number of chimpanzees housed per facility has generally increased. The GAIN database has tried to facilitate increasing awareness of the vital importance, to good welfare, of housing chimpanzees within social groups. On 31st March, 2014, there were 323 chimpanzees in 51 facilities. Data provided by GAIN, and summarized in this paper, will hopefully aid the establishment of an action plan for good welfare, care, management and reproduction strategies to develop a self-sustaining population of captive chimpanzees in Japan.

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勝山ニホンザル集団において，怪我をした1歳半のオスの子へ母親が行った行動を調べた。その子が怪我をする前後や，怪我をしていない同年齢の子を持つ2頭の母親との間で，その行動を比較した。1歳半のオスの子は後肢に怪我をしたため，後肢を引きずって移動するようになった。その母親は，以前に比べて，怪我をした子へ多く身体接触や毛づくろいをしていた。また，その子が怪我をする以前の観察中には，distress callは記録されなかったが，怪我をした後には，母親と接触していない時に，distress callを頻繁に発していた。怪我をした子の母親は，子のdistress callの後，他の2頭の母親よりも高い割合で，子に毛づくろいをしていた。これらの結果は，母親に強く依存してはいない1歳を過ぎた子が怪我をしたときに，子のdistress callに応じて，母親が子へ毛づくろいを多く行うようになったことを示唆している。

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Here, we have reported two cases of diurnal stillbirths in free-ranging groups of Japanese macaques (Macaca fuscata), Arashiyama and Koshima groups. One infant was born prematurely and in breech position, while the other seemed to be a full-term infant born in front position. The two mothers had little interaction with other members of the group throughout parturition. The group members, except for juveniles, also showed little interest in the mothers.
The mother of the infant born in the breech position licked the body of the infant, as in the case of live births. Moreover, both mothers carried the infants ventrally. However, the two mothers also showed behaviors that were different from those usually observed after a live birth. The mother of the infant born in breech position tore parts of the infant's skin and ate them. The other mother dragged the infant by grabbing the umbilical cord.
Previous studies have reported that mothers carry infants that died after birth, but it was unclear whether interactions with live infants were required for such maternal behavior. Our observations suggest that some maternal behaviors can be observed even when the infants die before parturition. At the same time, the cases reported by us show the possibility that infants born dead may influence the expression of certain unusual behaviors.

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