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Classification of Assamese macaque and related taxa is now in confusion. In Sub-Himalayan region, western and eastern Assamese macaque (M. a. pelops, WAM; M. a. assamensis, EAM) range on the right and left banks of Brahmaputra River, respectively. Arunachal macaque (M. munzala, MUN) was described from western Arunachal Pradesh (AP) in 2005. Biswas et al. (2011) reported MUN is distributed over AP. MUN or similar form are also reported from E and W Bhutan highland. Only tail length is the meaningful classification trait in Assamese macaques. WAM's tail is longer than EAM's, and MUN's is comparable or slightly longer than EAM's. Assamese macaques in Nepal are suggested to be separate taxon (subspecies?) with distinctive traits, especially longer tails than WAM in Sikkim and West Bengal. Tibet macaque-like monkey was reported from AP. Recently, a new species M. leucogenys (ML) was described from SE Tibet, adjacent to AP, with the tail of comparable length to that of MUN. These taxa are claimed to have unique traits, though they appear similar to Assamese macaques or states of their traits are on the spectrum of variation. From genetic analysis, WAM was found to have diverged by hybridization between M. radiata or its ancestor (females) and M. a. assamensis/M. thibetana (males), with phenotypes assimilated to EAM. The same genetic makeup was reported for MUN (for W AP population, and Bhutan populations). S and E Asia are separated by barrier zone with such conditions as Himalayan Range, Brahmaputra River, and climate. In remote past, one population of sinica-species group dispersed to the S Asia across the barrier, producing bonnet and toque macaques. There were substantially no gene flow with eastern sister taxa (Assamese and Tibetan macaques), i.g., migration of population. Macaque populations of radiata phylogeny have adapted sub-Himalayan region. In favourable climate times, male EAM have dispersed temporarily from E Asia across the barrier zone to establish gene flow (introgression), producing WAM and related taxa. As they have adapted more or less to the highland, and local populations ranging high altitude areas tend to be isolated with each other, like insular populations, making traits accentuated according to the geographical structure (e.g., pelage color pattern). Thus, forms have diverged. It is also probable that there is a spectrum of the strength of introgression from E Asian taxon, making the spectrum of trait states, e.g., length of tail, between Nepal, North India, Bhutan, AP and SE Tibet.

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The evolution of langurs and macaques in southern Asia is a topic of growing interest, and Sri Lanka is an important but understudied piece of this puzzle. Sri Lanka, situated southeast of India with a geological history of being connected to the sub-continent several times, is classified as one of the world biodiversity hot spots in terms of species, genetic, ecosystem, and geographical diversity. The three sub-species of the endemic toque macaque (TM), the four sub-species of the endemic purple-faced langur (PFL), and the Hanuman or grey langur (GL), a species found across the Indian subcontinent, are distributed across the diverse mosaic of climatic and ecological zones of Sri Lanka. We previously reported a disparity between the phenotypic and mtDNA diversity of toque macaques, whereby all three purported subspecies came under two major mtDNA haplogroups, segregated roughly into two different major elevation zones; mountainous and coastal regions. In this study we present preliminary results on the phylogeography of GL samples. Eighty-two Sri Lankan GL samples (64 feces, 20 blood) originating from 22 different populations across the species' distribution were analyzed. DNA was extracted and the successfully amplified PCR product was sequenced for cytb and D-loop. GL clustered mainly into one large cluster, with 4 minor clusters. Further analysis and sample collection will be necessary before coming to firm conclusions, but PFL clustered with GL into the same haplotype in one small cluster where they live sympatrically, suggesting local hybridization.

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Mammals are exposed to a large array of parasites that may dramatically affect host fitness. Species living in large groups are especially exposed. An increased exposure to parasites has been proposed to be one of the major costs of sociality. Parasites are thought, however, to represent a selection force driving the evolution of host social system, possibly shaping specific host behavioral patterns. Here, we studied the influence of intestinal parasitism on social behavior in a wild mandrill population as well as a proximate mechanism responsible for the detection and the avoidance of parasitized individuals. By coupling chemical, behavioral and parasitological analyses, we showed that some intestinal parasites, transmitted by physical contacts between hosts, involve a decrease in sociality of infected individuals. Besides, some of these parasites appeared to modify the fecal odorants of infected animals. These results suggest that parasitism may represent a selection force acting directly on social behavior: individuals could adapt to important parasitic pressures by elaborating recognition mechanisms based on odorants, allowing behavioral avoidance of infected individuals.

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Bitter taste perception is widely known as a key defence against ingestion of toxic components. Bitter recognition is mediated by a bitter receptor encoded by T2R multigene families. One member of T2Rs is T2R38 that encode receptor for phenylthiocarbamide (PTC). In primates, polymorphism in T2R38 had been identified in human, chimpanzee, and Japanese macaques that lead to different behavioral response of individual. Among primates, leaf-eating monkeys (Subfamily Colobines) are unique because their diet consisted mostly of leaves that perceptually tasted bitter to human. Preliminary behavioral experiments of PTC-tasting on leaf-eating monkeys kept in Ragunan Zoo indicated that nine individuals of genus Trachypithecus, Presbytis and Nasalis were all non-tasters. This study aimed to investigate the genetic of that behavioral by sequencing those gene and to assay the sensitivities of T2R38s of leaf-eating monkeys using cell expression system. The sequences of T2R38 gene from leaf-eating monkey indicated that all gene should encode functional protein to taste PTC, in comparison with human taster. Thus, genetic result is in contrary with non-taster result. Then, we expressed those gene in cell expression system and found that some of T2R38s of Colobines showed either low response or no responce against PTC. The result is in match with the behavioral experiment.

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Macaques are considered as a useful animal model for osteoporosis (OP) and osteoarthritis (OA) because they manifest bone loss and an increasing severity of OA with advancing age and with estrogen depletion. Japanese (Macaca fuscata, Mfus) and cynomolgus macaques (M. fascicularis, Mfas) are closely related with each other, though they showed various species specific characteristics mainly related to body size and reproductive physiology, which may influence on their bone mass and OA prevalence. We investigated age-related and reproductive aging-related bone changes, assessing radial bone mineral density (BMD) and content (BMC) at both trabecular and cortical sites; and for OA, disc space narrowing (DSN) and osteophytosis (OST) in lumbar vertebrae in female Mfus and Mfas. Subjects were divided into 2 groups by age in Mfus into U₂₅ group of <25 years of age (N = 55, 6-24 years) and O₂₅ group of ≥25 years of age (N = 6; 26-29 years) and in Mfas into Pre group (premenopausal, N = 73, 5-27 years) and Post group (postmenopausal, N = 9, 31-37 years). We found that the heavier Mfus (average 9.2 kg) had significantly higher BMD and BMC than the lighter Mfas (average 3.5 kg). However, no significant differences were observed in lumbar OA aggravation with age between the two species, in spite of the fact that body mass (BM) significantly influence on OA in humans. It is perhaps because macaques had greatly severer OA development than women. The two macaque species shared similar age-related bone changes: trabecular BMD and BMC and cortical BMC started decreasing from young adulthood in the absence of sex hormone deficiency; cortical BMD increased from young adulthood to the peak at around the perimenopause, and then decreased; and DSN and OST clearly increased with age. Significant acceleration in bone mass decrease and aggravation of OA were not observed neither from U₂₅ to O₂₅ in Mfus nor from Pre to Post in Mfas. In conclusion, female Mfus and Mfas had similar age-related and reproductive aging-related bone changes and shared certain aspects of bone changes with women. Longitudinal study is necessary whether macaques show significant acceleration in bone loss with estrogen depletion, which was not found at the trabecular site but possibly at the cortical site in the present study.

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Male competition for mates has a great impact on their behavior, physiology and social system. Bonobos (Pan paniscus) are well known for their peaceful and mild characteristics compared with those of chimpanzees. One hypothesis explaining their peaceful nature is their high operational sex ratio. In other words, female bonobos are highly receptive lending to milder mating competition than seen in chimpanzees. Female bonobos have the longest period of maximal sexual swelling among species in which sexual swelling is found. Many researchers agree that prolonged periods of maximal swelling might help females conceal their peri-ovulatory period. This infers that male bonobos cannot detect a female ovulatory period, or that they do not seriously care about producing offspring. However, considering the fact that ovulation is usually situated in the later half of swelling periods, it is possible that male mating activity has been selected to occur more frequently around peri-ovulatory periods. Moreover, many previous studies have not fully considered the reproductive history of females as an important factor in determining the resumption and continuation of her menstrual cycle. In this study, we tested hypothesis that males can determine peri-ovulatory periods of females. We predicted that males may exclusively follow females with maximal swellings in the party during daily ranging. In particular, the alpha male, who can displace all other males in the party, can follow a female with maximal swelling all day, thereby monopolizing copulation opportunities. When there are several females in maximal swelling, group males may choose to follow the female with older dependent offspring, and whose maximal swelling phase started earliest and has continued for more days. This tendency will be most clear for the alpha male. Hormonal profiles of these females are currently being analyzed, and are expected to provide needed evidence to test our hypothesis in a more quantitative way.

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Female primates signal their reproductive state through behavioral, visual (e.g. swelling size), auditory (e.g. copulation calls) and olfactory (i.e. vaginal odorant compounds) cues. To date however, studies have generally focused on ovulatory signaling, and the multimodal advertisement of pregnancy is still largely uninvestigated. We aimed to determine if female Japanese macaques (Macaca fuscata) advertise their pregnancy via changes in behavioral, visual and auditory sexual signals, and the role of these signals in male mating decisions. We combined digital photography, behavioral and endocrinological (progestogen and estrogen) data from 5 females, for three one-month periods: pre-conceptive period, first month of pregnancy and second month of pregnancy. We found that males and females did not copulate during pregnancy, and that most sexual behaviors (e.g. male and female approaches, male holding behaviors) decreased between the pre-conceptive and the pregnancy period. Female faces became significantly darker from the pre-conceptive period to pregnancy, and face redness significantly decreased between the 1^st and 2^nd month of pregnancy. Estrus call frequency was significantly lower during the 1^st month of pregnancy compared to the pre-conceptive period and the 2^nd month of pregnancy. The ratio of female sexual steroids during pregnancy was correlated to estrus call frequency. Our results suggest that pregnancy in Japanese macaques is signaled multimodally (i.e. behavioral, visual and potentially auditory signals), which is likely to provide benefits to both sexes. Females and males could decrease the overall cost of mating, with females allocating their energy to fetal growth, and males focusing their reproductive effort on cycling females.

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Humans often activate a mental representation of a number line when performing quantitative tasks. This is illustrated in the spatial numerical association of response codes (SNARC) paradigm in which people report whether a sample number is odd or even. Humans respond more quickly on the left when the number is small and on the right when the number is large. This indicates that responding is facilitated when the response is congruent with the mental number line even though no explicit magnitude processing is required. The capacity to represent space is fundamental and available to many species. To determine whether spatial representations are involved in quantity processing across species, we tested for SNARC phenomena in monkeys. Monkeys matched the color of a sample array that ranged from 1 and 10 dots to color comparison stimuli on the bottom left and right sides of the screen. After being trained to associate small with left responses and large with right responses, monkeys were more accurate in color matching when responding on the left after seeing a small numerosity sample. This effect reversed after monkeys were trained in the opposite spatial association. These results are consistent with a spatial representation of magnitude in monkeys.

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The aim of this study is to investigate spatial reference in captive chimpanzees (Pan troglodytes). Reference is the ability to communicate with others about events or objects in the environment. It is a fundamental component of human communication, playing a crucial role in social skills and language development. Spatial reference concerns more specifically the spatial location of objects being referred to. Individuals divide the space into different areas (most often, near versus far space), and consequently resort to appropriate linguistic and gestural signals, to efficiently and accurately locate a referent. This distance contrast (near/far), thereafter referred to as distance encoding, appears to be a robust feature of referential communication, present in all aspects of multimodal pointing. The distance of a referent is thus encoded at a lexical, high language processing, level, and at a motor, low language processing, level. In other words, individuals use distance-specific linguistic units (such as “here” versus “there”), but also distance-specific oral and manual gestures, to designate a close versus a distant referent. This suggests a close connection between linguistic structures and communicative gestures. We believe that looking for such distance encoding in our closest living relatives signaling could provide valuable information on the emergence of referential communication. We are thus investigating the ability of eight captive chimpanzees to adjust their communicative signals according to the spatial properties of a referent. For that purpose, we are using a food-requesting paradigm, where a piece of food is located either in the chimpanzees proximal space (‘near’ condition) or in their distal space (‘far’ condition). Besides, chimpanzees are tested for their requesting behavior in two conditions, either with a human interlocutor (‘with human’ condition) or alone (‘without human’ condition). This will allow us to assess the communicative nature of the observed behaviors. Intentional communicative signals, such as pointing gestures, attention-getting gestures, and vocalizations, will be categorized as visual, auditory, or audio-visual signals. The relative proportion of each signal, and some qualitative features of manual gestures (e.g. shape, orientation and position of the hand), as well as those of each signals combination, will be compared between the ‘near’ and the ‘far’ conditions. Distance encoding, that would be here a systematic variation of the signals depending on the distance of the food, could manifest itself in many ways, including for instance a multimodal strategy (i.e. combinations of unimodal signals and/or use of multimodal signals per se)to designate a distant referent.

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Macaca fascicularis fascicularis (Mff) is the most commonly used animal models in biomedical research, and the knowledge on its genetic diversity within population and genetic divergence will help to gain accurate and precise results in the experiments. The hybridization between different species or subspecies has occurred widely in non-human primates. Due to their wide habitat ranges, Mff has been reported to hybridize either with their parapatric species (M. mulatta) at 15-20°N or with subspecies (M. fascicularis aurea; Mfa) at the vicinity of Isthmus of Kra (10° 15’N). However, the impact of Mff x Mfa hybridization was not evaluated. Therefore, the 38 somatometric dimensions were measured and phylogenetic analyses of mtDNA and Y-chromosome gene (SRY and TSPY) sequences were performed in Mff, Mfa, and hybrids. Mfa had infrazygomatic cheek hair pattern with dark pelage color, slender hand, relative shorter 3^rd finger and tail length, while Mff had tranzygomatic cheek hair and lighter pelage color, and the hybrids had mixed-characters. Based on mtDNA and Y-chromosome gene sequences, it denotes the Mfa first originated in Myanmar and migrated in two consecutive routes before hybridizing with Mff. Firstly, Mfa migrated southward along the Andaman seacoast towards southwestern Thailand when the sea level was low during mid- or late-Pleistocene epoch and hybridized with Mff. Secondly, they moved east-northwards across the low altitude area of the Dawna range and hybridized with Mff recently. Based on this preliminary result, hybridization between Mfa and Mff is found in restricted areas in Thailand.

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Ancient Chinese has accumulated rich knowledge on non-human primates that are widely distributed in China with written literature and folklore for several thousand years. We used the method of critical text analysis and discourse analysis to make clear when and how ancient Chinese distinguished gibbons from macaques. We divided the progress into four main stages, which include Pre-Shang to Shang Dynasty (before 1046 B.C.), Zhou to Han Dynasty (1046 B.C. - 220 A.D.), Six Dynasties to Song Dynasty (220 - 1279 A.D.) and Yuan to Qing Dynasties (1279 - 1840 A.D.). We found that China's traditional cognition of gibbons and macaques emphasized the appearance of animals, organoleptic performance or even whether their behaviors were ’moral’ or not. They described them as human-like animals by ethical standards but ignored the species itself. This kind of cognitive style actually embodies the ’pursuit of goodness’, which is the feature of Chinese traditional culture. This study presents some original views on Chinese traditional knowledge of non-human primates. Keywords: Chinese traditional culture, Non-human primates, Gibbon, Macaque, Cognitive feature

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The endemic Purple- faced leaf langur in Sri Lanka is represented by four sub species. Of the four sub species, the western purple faced leaf langur (Trachypithecus vetulus nestor-Bennet, 1835) has grayish black pelage colour and faint white rump patch and is mainly found in low tropical rain forests up to 1000m in the Western and Sabaragamuwa provinces. White morph of the western purple- faced leaf langur was first discovered during a survey in 2010 in the Galigamuwa Divisional Secretariat Division, Kegalle District, Sabaragamuwa Province. The habitats of these langurs are mainly rubber plantations and private home gardens. Initially all the black langur troops with white colour morph individuals were identified in the Aruggammana, Hathnapitiya and Kurunegoda GN divisions. Out of sixteen purple faced langur troops surveyed, white morphs were recorded in 12 troops. Twenty eight white morph purple faced langurs were recorded, which was comprised of eight adult males, 6 adult females and 14 sub adults/infants of unidentified sex. The white morph purple-faced langurs are always associated with normal black colour langurs. In completely white individuals the face, crown hair, hair on the back of the head, ears and the eyes are black or reddish as in normal individuals. However their pelage colour, limbs and tails are completely white. The mixed coloured individuals have brownish ash patches on the under arms and on the back. Albinism can be ruled out as their faces and other areas of exposed skin are black and they do not have red eyes. Western Purple-faced leaf langurs are endemic and critically endangered due to habitat loss. The discovery of white morph of these sub species makes it more important to conserve these animals in terms of preserving their biodiversity.

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Displaying aversive reactions toward a disadvantageous inequity is a well known phenomena in humans. This kind of sensitivity to unfair outcomes, together with the sensitivity to unfair intentions or actions, is known to regulate reciprocity and to stabilize cooperation. Much work has demonstrated that this behavioral trait is not unique to humans, but also occurs in other primate species. However, it still needs to be examined whether this aversion to disadvantageous inequity can be further employed in an animal’s actual choice to punish the partner who gets better rewards then themselves, by being spiteful. The current study therefore was designed to test whether chimpanzees’ prosocial choices are influenced by differential reward distributions (equal/advantageous/disadvantageous) and also by unfair behaviors (prosocial/selfish) of human partners. Unlike other inequity tasks, we used a prosocial choice experiment to give the chimpanzees an active role to be prosocial or selfish toward their partner. In experiment 1, we tested 2 female chimpanzees at the Primate Research Institute, Kyoto University with 3 females from the same group to test aversion to outcome disparity. In experiment 2, the same chimpanzees who participated in experiment 1 as an actor, were tested with 4 familiar humans who were randomly assigned either to be prosocial or selfish by making 8 consecutive prosocial or selfish choices toward the chimpanzee. Our results show that the chimpanzees show aversive reactions when they themselves had a less preferred reward than their partners by rejecting to do the task. Especially, one chimpanzee, Pendesa, showed display behaviors toward the subordinate recipient, but not toward the dominant recipient who was having a more preferred reward than her. However, this behavioral tendency did not lead chimpanzees to make selfish choices. This was also true when they were paired with human partners. Further experiments should be carried out in order to test whether these tendencies resulted from relationship quality which influences the tolerance for inequity, suggested by other studies, or from other factors, such as avoidance of future revenge, etc.

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The k-shape Sulawesi Island (Central Indonesia) is the interface of Asia/Oriental and Indo-Australian zoogeographical realms where endemism level is high. Of the 127 mammal species indigenous to Indonesia, 79 (62%) are endemic to Sulawesi. The most apparent among these are seven species of monkeys of the genus Macaca that are distributed allopatrically. The Sulawesi macaques are thought of as having an ancestor that was a member of the stock that lived in continental Asia. From Sunda Land, insular part of Asia/Oriental zoogeographic realm, they crossed Wallace Line to enter Sulawesi. There are three issues regarding the evolution of Sulawesi macaques. The first is taxonomic status, the second phylogenetic relationship, and the third hybrid population problem. The key to answer these questions is how to identify individuals in assigning them to any technical groupings that may or may not relate to taxonomic value. In their speciation into the Sulawesi macaques they differentiated their external morphological characters to become various morphs. These variations are readily observed, however, the available descriptions by Fooden (1969) were based on museum specimens that prone to change. Here we review the Fooden's external characters by compare it to observations gathered on live monkeys in the island. The variations of the characters are enormous and we had to take the three questions above in mind in defining their states. We succeeded to record thirteen size, shape and color polymorphic characters. We apply the resulting definitions to categorize seven morphological groupings in accordance to Fooden's (1969) taxonomic review.

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Interest is growing in attempts to understand animal behaviour towards dead conspecifics, especially among nonhuman primates. Although rare, infant-corpse-carrying is evident in many nonhuman primate species. However, in Japanese macaques it is relatively common, on average lasting several days. The combination of dead-infant-carrying for at least a day followed by filial cannibalism has been reported in one wild bonobo and two rehabilitant orangutan mothers. We report the first instances of dead-infant carrying followed by filial cannibalism in a monkey, housed socially. We present two cases of infant-corpse-carrying for 4 weeks, then filial cannibalism in a female Japanese macaque in two consecutive births. The individual (wild-born) was one of 25 individuals housed in a large outdoor enclosure (3800m²) with natural vegetation. We discuss the implications of our findings. Our observations are also unusual for the exceptionally long period of infant-corpse-carrying. On both occasions the mother carried the corpse until mummified: in 2011 for 29 days and in 2013 for 28 days. In 2011 she consumed all the dried flesh on day 28, yet continued carrying the skeletal remains intermittently for another day. In 2013 she chewed the corpse on day 23. This research complied with the Kyoto University Primate Research Institute guidelines for care and use of nonhuman primates. *The two first authors contributed equally to the research

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In nonhuman primates yawning is often classified as one of three types physiological response (e.g. regulating blood oxygen levels; increasing arousal), a sign of tension or anxiety, or a form of threat. So-called “threat yawns” are described especially in adult male Old World monkeys, who yawn more frequently than adult females. There is a lack of evidence for a similar sex difference in great apes. However, observations of lowland gorillas using open swamp areas in Gabonese rainforest revealed a greater frequency of yawning by adult males, especially silverbacks, than by other age-sex classes. Yawning occurred in relatively cool and rainy weather conditions. During rainy spells the gorillas became immobile and huddled to conserve body temperature. We suggest that yawning by silverbacks in this situation functions to increase arousal, important for group-leaders as they need to remain vigilant and ready to respond to any external threat to their group, such as from extra-group males or potential predators.

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To investigate the genetic basis of social behavior we searched for polymorphisms of the mu-opioid receptor gene (OPRM1) in chimpanzees. The non-synonymous polymorphism of the gene of the extracellular region has been reported to affect social behavior in humans and rhesus macaques. We surveyed a corresponding region in 135 chimpanzees kept in Japanese Zoos and found a 3 base pair indel (L: insertion, S: deletion) coding aspartic acid. L and S allele frequencies were 0.611 and 0.389, respectively. To survey personality three caretakers familiar with the chimpanzee answered 54 questions on a scale of 1-7. The 54 questions were categorized into six factors: Dominance, Extraversion, Conscientiousness, Agreeableness, Neuroticism, and Openness. To examine the association between genotype and personality we ran linear regression models with each personality component as the dependent variable and genotype and sex as independent variables. We first ran a basic model looking at the main effect of genotype. We then added sex as a main effect and the sex × genotype interaction. The main effects of genotype on Dominance, Extraversion, Agreeableness, Neuroticism, and Openness were not significant. For Conscientiousness we found a significant main effect and a significant interaction: chimpanzees homozygous for L had higher scores on Conscientiousness than chimpanzees with other genotypes (P = 0.0158) and this association was stronger for males than for females (P = 0.0226). We also surveyed the reported indel in promoter region of arginine vasopressin receptor gene (AVPR1a) and found that chimpanzees with a copy of the long allele had higher scores on Conscientiousness (P = 0.0382).

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