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Maternal monitoring of conspecifics is a crucial anti‐predator strategy that also protects infants against risks within the social group. This study examines how maternal characteristics, infant characteristics, mother–infant distance, and the social environment affect maternal monitoring behaviors in free‐ranging Tibetan macaques (Macaca thibetana). We observed 12 females with infants and analyzed their visual monitoring patterns. Our findings indicate that maternal rank significantly influences the time allocated to maternal visual monitoring, higher‐ranking mothers spending less time than lower‐ranking mothers. Maternal experience also played a role in monitoring strategies. Differences in monitoring strategies were observed based on maternal experience: first‐time mothers (primiparity) engaged in longer but less frequent monitoring sessions compared to experienced mothers (multiparity). The time and frequency of maternal monitoring decreased as infants aged, and mothers with male infants showed higher levels of monitoring than those with female infants. The distance between mother and infant also affected visual monitoring behavior, with mothers increasing their monitoring levels when infants were nearby (1–5 m), rather than within reach (0–1 m) or beyond nearby (>5 m). Additionally, the presence of kin and non‐kin influenced monitoring: as the number of nearby kin increased, monitoring levels decreased, while the presence of more non‐kin males led to an increase in monitoring time, and higher‐ranking non‐kin neighbors increased the frequency of monitoring. These results suggest that Tibetan macaque mothers can adapt their visual monitoring to the social risks faced by their infants, adjusting their strategies to their status and the needs of their offspring. [ABSTRACT FROM AUTHOR]

Simple Summary: The process of aging itself and the behavioral changes caused by aging have been extensively studied and recognized in the field of biology. In this study, we determined that age had no effect on social behavior in male Tibetan macaques (Macaca thibetana). Old female macaques were less likely to approach other monkeys. This study provides a new perspective on adjusting social interaction strategies in old non-human primates under nature environments. Aging can induce changes in social behaviors among humans and nonhuman primates (NHPs). Therefore, investigating the aging process in primate species can provide valuable evidence regarding age-related concerns in humans. However, the link between aging and behavioral patterns in nonhuman primates remains poorly comprehended. To address this gap, the present research examined aging-related behaviors exhibited by Tibetan macaques (Macaca thibetana) in their natural habitat in Huangshan, China, during the period from October 2020 to June 2021. We collected behavioral data from 25 adult macaques using different data collection methods, including focal animal sampling and ad libitum sampling methods. We found that among adult female macaques, the frequency of being attacked decreased with their age, and that the frequency of approaching other monkeys also decreased as age increased. In males, however, this was not the case. Our findings demonstrate that older female macaques exhibit active conflict avoidance, potentially attributed to a reduction in the frequency of approaching conspecifics and a decreased likelihood of engaging in conflict behaviors. This study provides some important data for investigating aging in NHPs and confirms that Macaca can exhibit a preference for social partners under aging-related contexts similar to humans. [ABSTRACT FROM AUTHOR]

Predicting the spatial distribution of species and suitable areas under global climate change could provide a reference for species conservation and long‐term management strategies. Macaca thibetana and Macaca arctoides are two endangered species of Chinese macaques. However, limited information is available on their distribution, and their habitat needs lack proper assessment due to complicated taxonomy and less research attention. In recent years, scholars widely used the maximum entropy (MaxEnt) model to predict the impact of global climate and certain environmental factors on species distribution. Therefore, we used the MaxEnt model to predict the spatiotemporal distribution of both macaque species under six climate change scenarios using occurrence and high‐resolution ecological data. We identified climatic factors, elevation, and land cover that shape their distribution range and determined shifts in their habitat range. The results demonstrated that temperature range, annual precipitation, forest land cover, and temperature seasonality, including the precipitation of the driest month are the main factors affecting their distribution. Currently, M. thibetana is mainly concentrated in central, eastern, southern, and southwestern China, and M. arctoides is mainly concentrated in three provinces (Yunnan, Guangxi, and Guangdong) in southern China. The MaxEnt model predicted that the suitable habitat for both species will increase with increased greenhouse emission scenarios. We also found that with the further increase in greenhouse emissions M. thibetana is expected to migrate to western China, and M. arctoides is expected to migrate to western or eastern China. This reinterpretation of the distribution of M. thibetana and M. arctoides in China, and predicted potential suitable habitat and possible migration direction, may provide new insights into the future conservation and management of these two species. Highlights: Potential macaque distributions were predicted using different climate change scenarios.Macaque distributions were compared under present and future climate conditions.Suitable habitat areas for Macaca thibetana and Macaca arctoides are expected to increasing.Annual precipitation and annual temperature affected distribution.We believe the two species are migrating to the west of China to adapt to climate change. [ABSTRACT FROM AUTHOR]

Simple Summary: Primate activity rhythms and time budgets are dictated by food availability, temperature, and social factor; thus, primates must adapt their behaviors to accommodate fluctuations in environmental change. We conducted a year-long field study in the Huangshan region to collect data on Tibetan macaques' behavior and local weather. We compiled and analyzed these data, explored Tibetan macaques' behavioral patterns, and analyzed the potential factors that differentiate these behavioral patterns. The results indicate that Tibetan macaques have two foraging peaks and one resting peak in a day. Temperature and food were the main factors affecting the activity time budget of Tibetan macaques. Tibetan macaques' daily activity time budgets are significantly different in sex and age group. Activity rhythms and time budgets are important to understand behavioral variability and adaptation in primates because animals normally use a behavioral adjustment as a preferential choice in response to environmental changes. Therefore, we observed a group of un-provisioned Tibetan macaques (Macaca thibetana) in Tianhu Mountain County Nature Reserve, Mount Huangshan, Southern Anhui, China. We used the instantaneous scan sampling method to collect behavioral data on their activity rhythms and time budget. The results showed that Tibetan macaques have two foraging peaks (9:00–10:00 and 14:00–15:00) and a resting peak at 12:00–13:00. They spent 31.96% resting, 28.59% foraging, 26.96% moving, 6.90% grooming, and 5.59% other. The total time of foraging and moving per month significantly and positively correlated with fruits and buds and negatively correlated with leaves. Different sexes and age groups demonstrated different activity time budgets, with adult males, adult females, and young macaques spending most of their time resting, grooming, and playing, respectively. We elucidated the effects of different environmental conditions on Tibetan macaques and their behavioral adaptation strategies. [ABSTRACT FROM AUTHOR]

Simple Summary: In social situations, people may unconsciously repeat their partners' small moves. Sometimes we can not help opening our mouths when we watch others yawn; other times, we subconsciously cross our legs like others. This phenomenon also exists in animals. We believe that this retained habit is beneficial to social animals. By observing a group of macaques, we found that close partners are more prone to have behavioral synchronization, which is conducive to the maintenance of the group. Behavioral contagion has been defined as a phenomenon in which an unlearned behavior automatically triggers a similar behavior in others. Previous studies showed that a behavioral contagion might have the function of strengthening social relationships, promoting group coordination and maintaining social cohesion. However, so far, there are few studies investigating the correlation between contagious scratching and social bonding. Tibetan macaques (Macaca thibetana) live in multi-male and multi-female cohesive matrilineal groups, and scratching is usually observed in their affiliated interactions. We investigated the process of scratch contagion in one group of free-ranging Tibetan macaques and explored whether behavioral contagion could consolidate social relationships and maintain social stability. Results showed that the scratching was contagious and correlated with relationship quality and spatial distance. In dyads with a higher Dyadic Composite Sociality Index (DSI), the contagion was strong. In addition, contagions occurred more frequently and faster among individuals nearer to each other. In terms of social groups, members with higher social centrality participated in more behavioral contagion, whether as expressers or observers. Our findings provide new perspectives for studying behavioral contagions in humans and animals. [ABSTRACT FROM AUTHOR]

In group‐living mammals, an individual's fitness depends, in part, on the quality of social relationships it has with others. Among species of nonhuman primates in which one sex is philopatric, individuals of that sex often develop strong social bonds and alliances with closely related kin. Less is known regarding the social processes used by dispersing adults to form stable bonds with nonkin in their new group. From May to December 2009, April to August 2010, September to December 2011, and February to May 2012, we collected data on grooming interactions in wild Tibetan macaques (Macaca thibetana), a female philopatric species, at Mt. Huangshan, China. Our goal was to compare social interactions and bond formation between resident males, recent immigrant males, and resident females. Our results indicate that recent immigrant males formed stable partner relationships with a small number of resident females and groomed these females more frequently or for longer than they received grooming. In contrast, resident males switched female grooming partners more frequently, received more grooming than they gave, and formed relationships with a greater number of female partners. We argue that the ability of recent immigrant male Tibetan macaques to maintain strong and persistent social bonds with a small set of resident adult females is a primary factor that enables them to establish residence in a new multimale–multifemale group. The present study provides new and important insights into the integrated social strategies used by dispersing males and resident females to maintain group stability. Highlights: Recent immigrant male Tibetan macaques establish strong social bonds and persistent partnerships with a small number of resident females as a social tool to integrate into their new group.In contrast, males who are long‐term residents of the group, frequently change female partners and exhibit less stable partner relationships.The study provides new and important insights into the integrated social strategies used by recent immigrant males, long‐term resident males, and resident females in maintaining group cohesion in a multimale–multifemale primate society. [ABSTRACT FROM AUTHOR]

The distribution and availability of microbes in the environment has an important effect on the composition of the gut microbiome of wild vertebrates. However, our current knowledge of gut-environmental interactions is based principally on data from the host bacterial microbiome, rather than on links that establish how and where hosts acquire their gut mycobiome. This complex interaction needs to be clarified. Here, we explored the relationship between the gut fungal communities of Tibetan macaques (Macaca thibetana) and the presence of environmental (plant and soil) fungi at two study sites using the fungal internal transcribed spacer (ITS) and next generation sequencing. Our findings demonstrate that the gut, plant and soil fungal communities in their natural habitat were distinct. We found that at both study sites, the core abundant taxa and ASVs (Amplicon Sequence Variants) of Tibetan macaques' gut mycobiome were present in environmental samples (plant, soil or both). However, the majority of these fungi were characterized by a relatively low abundance in the environment. This pattern implies that the ecology of the gut may select for diverse but rare environmental fungi. Moreover, our data indicates that the gut mycobiome of Tibetan macaques was more similar to the mycobiome of their plant diet than that present in the soil. For example, we found three abundant ASVs (Didymella rosea , Cercospora , and Cladosporium) that were present in the gut and on plants, but not in the soil. Our results highlight a relationship between the gut mycobiome of wild primates and environmental fungi, with plants diets possibly contributing more to seeding the macaque's gut mycobiome than soil fungi. [ABSTRACT FROM AUTHOR]

Coordination and consensus in collective behavior have attracted a lot of research interest. Although previous studies have investigated the role of compromisers in group consensus, they provide little insight into why compromisers would allow such social arrangements to persist. In this study, the potential relationship between group movements and conflict management in Tibetan macaques in Anhui province, China, was investigated using hierarchical cluster analyses. Some members with higher social centrality or social rank often formed a front-runner cluster during group movements. They had higher leadership success than individuals outside the front-runner cluster. Other members with lower social centrality or social rank often followed the group movements initiated by the front-runner cluster, and thus formed the compromiser cluster. Compromisers' proximity relations with front-runners increased with their following scores to front-runners. Compromisers had fewer events of being attacked when they followed group movements initiated by the front-runners. The compromising process made compromisers lose the choice of direction preference, but it could increase their individual safeties. This trade-off suggests that compromisers play a role of decision-maker in coordination and consensus scenarios among social animals. [ABSTRACT FROM AUTHOR]

Leadership is a key issue in the study of collective behavior in social animals. Affiliation–leadership models predict that dyadic partner preferences based on grooming relationships or alliance formation positively affect an individual's decision to follow or support a conspecific. In the case of many primate species, females without young infants are attracted to mother–infant dyads. However, the effects of mother–infant–female associations on affiliation–leadership models remain less clear. In free-ranging Tibetan macaques Macaca thibetana , we used social network analysis to examine the importance of "mother-infant-adult female" social bridging events as a predictor of who leads and who follows during group movement. Social bridging is a common behavior in Tibetan macaques and occurs when 2 adults, generally females, engage in coordinated infant handling. Using eigenvector centrality coefficients of social bridging as a measure of social affiliation, we found that among lactating females, initiating bridging behavior with another female played a significant role in leadership success, with the assisting female following the mother during group movement. Among nonlactating females, this was not the case. Our results indicate that infant attraction can be a strong trigger in collective action and directing group movement in Tibetan macaques and provides benefits to mothers who require helpers and social support in order to ensure the safety of their infants. Our study provides new insights into the importance of the third-party effect in rethinking affiliation–leadership models in group-living animals. [ABSTRACT FROM AUTHOR]

Vocal repertoires are basic and essential components for describing vocal communication in animals. Studying the entire suite of vocal signals aids investigations on the variation of acoustic structure across social contexts, comparisons on the complexity of communication systems across taxa, and in exploration of the evolutionary origins of species-specific vocalizations. Here, we describe the vocal repertoire of the largest species in the macaque genus, Macaca thibetana. We extracted thirty acoustic parameters from call recordings. Post hoc validation through quantitative analyses of the a priori repertoire classified eleven call types: coo, squawk, squeal, noisy scream, growl, bark, compound squeak, leap coo, weeping, modulated tonal scream, and pant. In comparison to the rest of the genus, Tibetan macaques uttered a wider array of vocalizations in the context of copulations. Previous reports did not include modulated tonal screams and pants during harassment of copulatory dyads. Furthermore, in comparison to the rest of the genus, Tibetan macaque females emit acoustically distinct copulation calls. The vocal repertoire of Tibetan macaques contributes to the literature on the emergence of species-specific calls in the genus Macaca with potential insights from social, reproductive, and ecological comparisons across species. Am. J. Primatol. 78:937-949, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Simple Summary: Body size and individual development are essential factors that affect primate movement through the canopy and access to food. However, only a few studies have been conducted on immature wild macaques. Although adults are significantly heavier than the other age groups, this study found that they did not exhibit higher frequencies of climbing and bridging. Jumps and suspensions were more frequent in juveniles than adults. We also found that juveniles exhibited rare behaviors during play, such as cling locomotion, suspensory locomotion, and bounding. We hypothesized that juveniles would exhibit diverse positional behaviors associated with altered skeletal muscle development. Diverse positional abilities facilitate habitat exploitation and the avoidance of danger. Body size and individual development significantly affect positional behavior and substrate use. However, only a few studies have been conducted on immature wild macaques. We studied wild Tibetan macaques (Macaca thibetana) inhabiting Mt. Huangshan, China, to explore the degree of interspecific variation in positional behavior in relation to body weight and individual development. From September 2020 to August 2021, we used instantaneous scan sampling (duration 5 min, interval 10 min) to record age–sex groups, locomotions, postures, and substrate attributes. The results showed that Tibetan macaques used terrestrial substrates in nearly two-thirds of the recorded observations. The main postural modes were sitting and quadrupedal standing. The main locomotor modes were quadrupedal walking and climbing among all age–sex group records. Positional behavior and substrate use in adults only significantly differed from those in juveniles and infants. Although adult males were larger than the other age–sex groups, they did not climb and bridge more frequently than the other age–sex groups. The frequency of climbing, leaping, and suspension was significantly higher in juveniles than in adults. In addition, adult males used terrestrial and larger substrates more frequently, while juveniles and infants used arboreal substrates and terminals more frequently than adult males during traveling and feeding. We hypothesize that the more positional behavioral spectrum of Tibetan macaque juveniles' may be related to rapid skeletal muscle development. These results suggest that differences in interspecific positional behavior may be caused by the individual development and survival needs of individuals, rather than just body size. [ABSTRACT FROM AUTHOR]

In several primate species, adult males are reported to compete for access to reproductive partners as well as forming affiliative and cohesive social bonds based on the exchange of goods or services. We hypothesized that among a broad set of fitness-maximizing strategies, grooming can be used by individual adult males to enhance social relationships through reciprocity and/or through the interchange of grooming for a different but equivalent good or service. We used focal animal sampling and continuously recorded dyadic grooming and agonistic interactions to test a series of predictions regarding male social interactions in a free-ranging group of Tibetan macaques ( Macaca thibetana) at Huangshan, China. During the non-mating season or between males of similar rank throughout the year, grooming effort given was matched by grooming effort received. However, lower ranking males groomed higher ranking males at a greater rate and/or for a longer duration during both the mating and non-mating periods. We found that higher ranking males directed less aggression towards males with whom they formed a frequent grooming partnership, indicating that grooming received was interchanged for increased social tolerance. These data suggest that individual male Tibetan macaques employ alternative social strategies associated with grooming reciprocity or interchange depending on dominance rank and rates of aggression, and highlight the importance of both biological markets and grooming reciprocity as behavioral mechanisms used by resident adult males to form and maintain affiliative social bonds. Am. J. Primatol. 75:1009-1020, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Simple Summary: Social play among immature individuals has been well-documented across a wide range of mammalian species. It represents a substantial part of the daily behavioral repertoire during immature periods, and it is essential for acquiring an appropriate set of motor, cognitive, and social skills. In this study, we found that infant Tibetan macaques (Macaca thibetana) exhibited similar patterns of social play between males and females, juvenile males engaged more aggressive play than juvenile females, and juvenile females engaged more affiliative play than juvenile males. Our results provided more evidence to understand the functional differences of social play in immature nonhuman primates. Theories proposed to explain social play have centered on its function in establishing social relationships critical for adulthood, its function in developing motor skills needed to survive, and promoting cognitive development and social learning. In this study, we compared variations in social play among infant and juvenile male and female Macaca thibetana. Given that this species is characterized by female philopatry and male dispersal, we hypothesized that immature females use social play as a mechanism to develop bonds that persist through adulthood whereas immature males use play to develop social skills needed to successfully enter new groups. The results indicated that social play steadily increased during the infant period and peaked at approximately 12 months of age. There were no significant differences in the frequency or types of social play exhibited between infant males and infant females. During the juvenile period, however, social play was found to decrease with age, with males engaging in social play more frequently than juvenile females. Moreover, whereas juvenile males engaged in more aggressive forms of play, juvenile females engaged in more affiliative forms of play. In addition, juvenile females engaged in higher rates of grooming than juvenile males. These results provide evidence of sex-specific differences and imply the functional variation of social play in Tibetan macaques, with immature males using social play to develop skills needed to enter and enhanced their dominance rank in a new social group and immature females using social play to develop long-term same-sex social bonds in their natal group. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]