Male Social Rank And Feeding Strategy Of Rhinopithecus Roxellana In Qinling Mountain

Hierarchies are common among social animals and non-human primates,and dominance hierarchies tend to affect animals' possession of food resources,spatial resources and mating resources.In group life,different levels of animals usual y adopt different strategies to enhance their fitness.As a typical social animal,the Golden snub-nosed monkey?Rhinopithecus roxellana?is composed of one-male multi-female unit?OMU?,which forms a special multi-level society,which forms an obvious social hierarchy among different OMUs.Under the condition of the food resources are limited,the food resources competitive pressure is bigger within the Golden Snubnosed monkey group,in the face of food competition pressure,different rank leader males tend to adopt different ways of competition for food resources,and the different rank males' feeding strategy way of competition with food for heavy layer competition cooperation mode in society and community structure change rule was very important.At the same time,it can helps us to know the mechanism of competition and cooperation within the breeding band for different OMUs,and then can reveals the role of females when the leader male join a fight.Our study site is located in the Zhouzhi National Nature Reserve,near to the vil age of Yuhuangmiao,we use the focal animal sampling,continuous recording metood to observe and record the behaviors and foraging data for five high rank males and five low rank males in breading band.The daily observation time is at 8:00 a.m.,and the end time is about 6:00 p.m.until the focal animal no longer feeding,the observation time is about ten hours a day.During the observation period of the whole day,we mainly recorded the time budget and forging data about the focal animal throughout the day.During the study period,we total observed 424 hours,the average observation time was 10.10 + 0.07 h a day,and total collected 236 times of aggression between different One-male Unit?OMU?.Through the time budget and feeding data analysis,the results indicate that: the energy intake per day was significantly higher for high ranked males than low ranked males(Linear mixed models,LMM,F_1,6.18 = 25.68,P < 0.05).Higher ranked males spent significantly more of their daily time budget feeding on the provisioned food(F_1,7.18 = 26.07,P = 0.001),and consumed significantly more provisioned food(F_1,6.18 = 60.21,P < 0.001),than lower ranking males.Lower ranked males spent significantly more of their feeding time consuming natural food than higher ranked males?F1,7.45 = 19.94,P < 0.05?.However,the mass of natural foods consumed per day?F1,5.18 = 0.02,P = 0.89?,and the rate of natural food consumption?F1,5.23 = 0.003,P = 0.96?,did not differ according to rank.Our activity budget data showed that high ranking leader males spent more of their time engaged in positive social behavior,which we defined as the sum of the times spent grooming other monkeys in their OMU,being groomed,mating,and embracing as a proportion of all recorded time,than low ranked males.In positive social behavior,the study results indicate that the high rank males spent more time in grooming and embracing(grooming: F1,7.34 = 14.75,P < 0.01;embracing: F_1,6.18 = 5.87,P < 0.05),to maintain the relationship with females.Female support for the OMU leader male in a fight was not affected by the rank of the OMU leader males that started fights?Generalized linear mixed models,GLMM: x₁² = 2.05,P = 0.15?or those that were attacked?GLMM: x₁² = 1.92,P = 0.17?.Finally,among the fights that involved at least one female,the number of females per OMU on average that became involved in a fight did not significantly differ between high and low ranking OMUs either when attacking another OMU(F_1,28.13 = 0.07,P = 0.79)or when being attacked by another OMU(F_1,7.67 = 3.02,P = 0.12).This suggests that high rank males has priority for provision food and spent more time consuming provisioned food,so high rank OMU leader males have more time engaged in social behaviors than lower ranking leader males.And the more positive social behaviors can make high rank OMU have strong social cohesion,however strong socially cohesive did not translate directly to females supporting their OMU leader male when the male was involved in a fight with another OMU leader male.OMU leader male rank,and hence OMU rank,did not affect whether female support was given or not.