Aggression And Social Play Of Rhesus Macaques(Macaca Mulatta) In Hongshan Forest Zoo Of Nanjing

Aggressive behavior is a series of attacks and yield behaviors that occurs between two individuals or among multiple individuals,families,and groups.Both advantages and disadvantages can be taken by aggression behavior to animals.The aggressive behavior allows individuals with superior genes to obtain mates in the competition,have mating rights,and eliminate the weaker ones who are not fit to the struggle for survival at the same time,so that the superior genes can be inherited.Aggressive behavior can also increase the individual's ability of sensitivity and combat,and it can have a stronger survivability in a harsh living environment,which is conducive to the development of the population.In addition to these advantages,an aggression can also bring harm to animals,such as injury or death in the course of the aggression.The occurrence of aggressive behavior is affected by many factors,such as social factors,physiological state,population size,relationship,rank and so on,which are also affected by environmental factors,such as food and other factors.Social play is a play behavior that occurs between two individuals or among multiple individuals.It is common in part of reptiles,birds,and mammals.As a common behavior in primates,its existence is of special significance to animals.In the process of social play,the physical function of juveniles can develop rapidly,laying a foundation for the individual's future survival skills and reproduction.Young individuals can establish good social relationships with other individuals in the course of social play in population.The occurrence of social play behavior is also affected by many factors,such as age,gender,rank,and kinship,which together affect the occurrence of social play.In this study,infrared camera was used to study the aggressive behavior and social play of Rhesus Macaques(Macaca mulatta)in Hongshan Forest Zoo of Nanjing.The research was mainly focused on the daily activity rhythm of aggressive behavior and social play,the seasonal difference of aggression,and the influential factors on duration of aggression and social play.The influence of the number of participating individuals and the each aggression type on the duration of aggression were analyzed,the influence of the number of playmates and the type of each play behavior on the duration of social play were analyzed,and the tendency of individuals of different ages to choose the type of aggression and the type of social play were also analyzed.The results of the study on Rhesus Macaques' aggression showed that 2,962 aggressions were recorded in the 20-day's video,including 1,405 bouts of chasing,382 bouts of threat,278 bouts of scratching,108 bouts of other aggressive behaviors,and 789 bouts of combinations of different aggressive behaviors.We analyzed the rhythm of the aggression with ANOVA,the rhythm of the aggression was significant,with two aggression peaks at 09:30?10:30 and 15:30?16:30,demonstrating the influence of feeding on the frequency of aggressions.We analyzed the seasonal difference of aggression via Kruskal-Wallis test,it was no significance.We analyzed the influence of the number of aggression participators and the type of aggression behavior on the duration of the aggression via Kruskal-Wallis test and Mann-Whitney U for pairwise comparisons.The results showed that the number of participators and the type of aggression behavior had significant effects on the duration of the aggression.In the course of an aggression,the more involved participating individuals,the longer duration of the aggression.The duration of combination of different aggression types is the longest,followed by chasing,other,threat and scratching.Juvenile individuals,subadult individuals and adult individuals more engaged in chasing aggressive behavior.The results of the research on the social play behavior of Rhesus Macaques'showed that a total of 7,496 social play were recorded in the 10-day's video,including 4,018 bouts of touching and catching,1,012 bouts of chasing,671 bouts of biting and wrestling,53 bouts of other play behaviors,and 1,742 bouts of combinations of different play types.We analyzed the rhythm of the social play with ANOVA,the rhythm of the social play was significant,with two play peaks at 08:30?09:30 and 10:30?11:30.We analyzed the influence of the number of playmates and the type of play behavior on the duration of the social play via Kruskal-Wallis test and Mann-Whitney U for pairwise comparisons.The results showed that the number of playmates and the type of play behavior had significant effects on the duration of the play behavior.In the process of play behavior,the more involved participating individuals,the longer duration of the social play behavior;The combination of the different play types had the longest duration,followed by biting and wrestling,touching and catching,and chasing.Juvenile individuals of 0 to 3-year-old engaged more in touching and catching play behavior,while the subadult or adult individuals engaged more in chasing play behavior.The study was focused the rhythm of Rhesus Macaques' aggression behavior and social play behavior,quantified the influential factors on the duration of aggressive behavior and the categories of aggressive behavior,quantified the influential factors on the duration of social play behavior and the categories of social play behavior,and provided quantified evidence for the management and welfare of the Rhesus Macaques.