Why China is important in advancing the field of primatology

Over the past few decades, field studies conducted by Chinese primatologists have contributed significant new theoretical and empirical insights into the behavior, ecology, biology, genetics, and conservation of Iorises, macaques, langurs, snubnosed monkeys, and gibbons. With the recent establishment and inaugural meeting of the China Primatological Society in 2017, China has emerged as a leading nation in primate research. Several research teams have conducted long-term studies despite the difficult challenges of habituating and observing wild primates Inhabiting mountainous temperate forests, and the fact that some 80% of China＇s 25-27 primate species are considered vulnerable, endangered, or critically endangered and are distributed in small isolated subpopulations. In going forward, it is recommended that primatologists in China increase their focus on seasonal differences in the social, ecological, physiological, and nutritional challenges primates face in exploiting high altitude and cold temperate forests. In addition, provisioning as a habitation tool should be minimized or eliminated, as it is difficult to control for its effects on group dynamics, patterns of habitat utilization, and feeding ecology. Finally in the next decade, Chinese primatologists should consider expanding the taxonomic diversity of species studied by conducting research in other parts of Asia, Africa, and the Neotropics.

Habitat restoration is the greatest challenge for population recovery of Hainan gibbons(Nomascus hainanus)

Hainan gibbons are among the world’s most critically endangered primates,with a remaining population of only 35 individuals distributed across 5 social groups in the Bawangling Branch of the Hainan Tropical Rainforest National Park,China.Habitat conversion and forest fragmentation over the past 40 years have reduced their geographical distribution by 95%.In the absence of a quantitative assessment of the availability of remaining suitable habitat,it is unclear whether this species can survive to the end of this century.We used behavioral observations,ArcGIS,remote sensing,stereo optical imagery,and MaxEnt modeling to identify patterns of Hainan gibbon range use and compare changes in the distribution of suitable forest types and areas of forest fragmentation over the past 20 years(2000–2020).The results indicate that the combined range of the 5 extant Hainan gibbon groups totaled 14.89 km2.The home range of the smallest group(Group E,3 individuals)was 1.51 km2,which likely represents the minimum home range size for this species.The remaining area of highly suitable and moderately suitable habitat totals 26.9 km2.However,habitat connectivity across the gibbon range is very low(less than 0.5),limiting the ability of Hainan gibbons to move between forest patches.The results of this study indicate that the availability of suitable habitat in Bawangling is insufficient to allow for future Hainan gibbon population growth.Therefore,immediate action must be taken to restore,reforest,and establish ecological corridors to reconnect areas of suitable habitat for these critically endangered gibbons.

Infant attraction:why social bridging matters for female leadership in Tibetan macaques

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 allianee formation positively affect an in dividua I's decision to follow or support a con spec ific.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-rangi ng Tibeta n macaques Macaca thibetana,we used social network analysis to examine the importance of mother-inf a nt-adult female"social bridging eve nts as a predictor of who leads and who follows during group movement.Social bridging is a common behavior in Tibetan macaques and occurs whe n 2 adults,gen erally females,engage in coordinated in fa nt 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 sign讦icant role in leadership success,with the assisting female following the mother during group movement.Among non lactati ng females,this was not the case.Our results in dicate that in fa nt attracti on 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.

Specialized digestive adaptations within the hindgut of a colobine monkey

In mammal herbivores,fiber digestion usually occurs predominantly in either the foregut or the hindgut.Reports of mechanisms showing synergistic function in both gut regions for the digestion of fiber and other nutrients in wild mammals are rare because it requires integrative study of anatomy,physiology,and gut microbiome.Colobine monkeys(Colobinae)are folivorous,with high-fiber foods fermented primarily in their foreguts.

Comprehensive Knowledge of Reservoir Hosts is Key to Mitigating Future Pandemics

Coronavirus disease 2019(COVID-19)and other epidemics(such as severe acute respiratory syndrome[SARS],Ebola,and H1N1)are stark reminders that knowledge of animal behavior and ecosystem health are key to controlling the spread of zoonotic diseases early in their onset.However,we have very limited information about the set of behavioral and ecological factors that promote viral spillover and the effects that has on ecosystem health and disease transmission.Thus,expanding our current knowledge of reservoir hosts and pandemics represents an urgent and critical tool in ecological epidemiology.We also propose to create an integrative database that ranks animal species in terms of their likelihood as hosts for specific infectious diseases.We call for a global and cooperative effort of field and laboratory scientists to create,maintain,and update this information in order to reduce the severity of future pandemics.

Major histocompatibility complex and mate choice in the polygynous primate:the Sichuan snub-nosed monkey(Rhinopithecus roxellana)

The highly polymorphic genes within the major histocompatibility complex(MHC)not only play a major role in immunity resistance,but also seem to provide hints for mate choice in some animal populations.In the pres­ent study we investigated MHC-related mate choice in a small natural population(group size 40-55 individuals)of a polygynous primate,the Sichuan snub-nosed monkey(Rhinopithecus roxellana).We found that there was no evidence either for MHC-disassortative mating,or for females to mate with males based on MHC hetero­zygosity or specific alleles.Nevertheless,of the 11 alleles identified,we found that the frequencies of 2 alleles,Rhro-DRB2(P<0.01)and Rhro-DRB5(P<0.05)were higher in offspring than in their parents.These findings suggest that MHC-DRB in this population of R.roxellana is unlikely to be associated with mating preferences.Limited female opportunities for mate choice are likely due,in part,to the harem breeding structure present in R.roxellana,and the relatively small number of resident adult males in our study band(N=4-6).In addition,we suggest that differences in the frequency of particular alleles across generations may be linked to parasite resis­tance in a fluctuating environment;however,confirmation of this finding requires further study.