Although seasonal breeding has been documented in many non-human primates, it is not clear whether sexual behaviors show seasonal variation among male individuals. To test this hypothesis, the focal animal sampling me...Although seasonal breeding has been documented in many non-human primates, it is not clear whether sexual behaviors show seasonal variation among male individuals. To test this hypothesis, the focal animal sampling method and continuous recording were used to investigate seasonal variation and synchronization of sexual behaviors in five male Tibetan macaques （Macaca thibetana） at Mt. Huangshan from Oct 2005 to Sept 2006. Both copulatory and sexually motivated behaviors （i.e., sexual chase, grimace, and sexual-inspection）, which were significantly higher in the mating season than non-mating season. Furthermore, seasonal variations of sexual behaviors, including copulatory and sexually motivated behaviors, were synchronized among males. The results shed light on sexual competition and tactics for reproductive success of male M. thibetana and other non-human primates with seasonal breeding.展开更多
Self-directed behavior(SDB) is characterized as an indicator of anxiety, frustration and stress in nonhuman primates. In this study, we collected self-directed behavior data from one group of free-ranging Tibetan maca...Self-directed behavior(SDB) is characterized as an indicator of anxiety, frustration and stress in nonhuman primates. In this study, we collected self-directed behavior data from one group of free-ranging Tibetan macaques(Macaca thibetana) at Mt. Huangshan, China(September 2012–May 2013) using a combination of behavioral sampling methods including focal animal sampling, behavioral sampling, continuous sampling and instantaneous sampling. Our results showed that females engaged in significantly higher rates of self-directed behavior when they were in proximity to dominant individuals compared to subordinate ones. Conflict losers significantly increased their SDB rates after agonistic episodes, indicating that SDB might also serve as an index of anxiety in M. thibetana. We further found that females significantly increased their SDB rates when focal individual was proximity to weakly affiliation relationship higher rank members than to strongly affiliation relationship higher rank members. If conflicts were not reconciled, the postconflict SDB rates of losers were higher when they stayed with strongly affiliation opponents; if conflicts were reconciled, victims of strongly affiliation relationships opponents engaged in more SDB rates before reconciliation than after reconciliation, while victims of moderately affiliation relationships opponents did not engaged in more SDB rates before reconciliation than after reconciliation. We conclude that both of dominance rank and affiliation relationships might both influence the SDB rates of female Tibetan macaques significantly, suggesting that SDB is not only an index of anxiety in Tibetan macaques, but also can provide a new insight into evaluation of social relationships between individuals.展开更多
In some non-human primates, infants function as a social tool that can bridge relationships among group members. Infants are a desired commodity for group members, and mothers control access to them. The biological ma...In some non-human primates, infants function as a social tool that can bridge relationships among group members. Infants are a desired commodity for group members, and mothers control access to them. The biological market theory suggests that grooming is widespread and represents a commodity that can be exchanged for infant handling. As a limited resource, however, the extent to which infants are interchanged between mothers(females with an infant) and non-mothers(potential handlers,females without an infant) remains unclear. In this study, we collected behavioral data to investigate the relationship between grooming and infant handling in free-ranging Tibetan macaques(Macaca thibetana)at Mt. Huangshan, China. Our results showed that females with infants received more grooming than females without infants. After her infant was handled,mother females received more grooming than they did during daily grooming interactions. However, with the increasing number of infants within the social group, both the grooming that mothers received and the grooming that non-mothers invested for handling infants decreased. We also found that non-mothers invested more time in grooming to gain access to younger infants than older infants. Our results provide evidence that infants are social commodities for both mother and non-mother females. Mothers use infants for obtain grooming and non-mothers use grooming to gain access to infants. The current study implies a bidirectional and complex interchange pattern between grooming and infant handling to compensate for the dyadic grooming disparity in non-human primates.展开更多
Though females are generally more selective in mate choice, males may also benefit from mate choice if male reproductive success is limited by factors other than simply the number of female mates, and if females diffe...Though females are generally more selective in mate choice, males may also benefit from mate choice if male reproductive success is limited by factors other than simply the number of female mates, and if females differ in short-term reproductive potential. We studied male mate choice in a free-ranging troop of Tibetan macaques Macaca thibetana at Mt. Huangshan, China, from August 2007 to April 2008. We employed focal animal sampling and all occurrence sampling to record sexual related behaviors. Eight adult females were divided into three female quality categories according to the females＇ age, rank and parity. Using male mating effort as a proxy for male mate choice, we found that males do distinguish female quality and show time-variant mating strategies. Specifically, females with dominant rank, high fecundity, and middle age attracted significantly more males. Our results suggest that female short-term reproductive potential appears to be an important variable in determining male mating effort. Male Tibetan macaques do exercise mate choice for higher quality females as well as reduce useless reproductive cost, which is consistent with the direct benefits theory of mate choice.展开更多
The Tibetan macaque, which is endemic to China, is currently listed as a Near Endangered primate species by the International Union for Conservation of Nature （IUCN）（2017）. Short tandem repeats （STRs） refer to r...The Tibetan macaque, which is endemic to China, is currently listed as a Near Endangered primate species by the International Union for Conservation of Nature （IUCN）（2017）. Short tandem repeats （STRs） refer to repetitive elements of genome sequence that range in length from 1-6 bp. They are found in many organisms and are widely applied in population genetic studies. To clarify the distribution characteristics of genome-wide STRs and understand their variation among Tibetan macaques, we conducted a genome-wide survey of STRs with next-generation sequencing of five macaque samples. A total of 1 077 790 perfect STRs were mined from our assembly, with an N50 of 4 966 bp. Mono-nucleotide repeats were the most abundant, followed by tetra- and di-nucleotide repeats. Analysis of GC content and repeats showed consistent results with other macaques. Furthermore, using STR analysis software （IobSTR）, we found that the proportion of base pair deletions in the STRs was greater than that of insertions in the five Tibetan macaque individuals （P〈0.05, t-test）. We also found a greater number of homozygous STRs than heterozygous STRs （P〈0.05, t-test）, with the Emei and Jianyang Tibetan macaques showing more heterozygous loci than Huangshan Tibetan macaques. The proportion of insertions and mean variation of alleles in the Emei and Jianyang individuals were slightly higher than those in the Huangshan individuals, thus revealing differences in STR allele size between the two populations The polymorphic STR loci identified based on the reference genome showed good amplification efficiency and could be used to study population genetics in Tibetan macaques. The neighbor-joining tree classified the five macaques into two different branches according to their geographical origin, indicating high genetic differentiation between the Huangshan and Sichuan populations. We elucidated the distribution characteristics of STRs in the Tibetan macaque genome and provided an effective method for screening polymorphic STRs. Our results also lay a foundation for future genetic variation studies of macaques.展开更多
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 af...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.展开更多
有效性比(operational sex ratio,OSR)是指性成熟雄性数量与发情雌性数量的比值,可作为测量性选择强度的指标。本文对两种有效性比的黄山短尾猴(Macaca thibetana)鱼鳞坑YA1群和YA2群成年雄性在交配期(2007年8—12月)内的繁殖行为和攻...有效性比(operational sex ratio,OSR)是指性成熟雄性数量与发情雌性数量的比值,可作为测量性选择强度的指标。本文对两种有效性比的黄山短尾猴(Macaca thibetana)鱼鳞坑YA1群和YA2群成年雄性在交配期(2007年8—12月)内的繁殖行为和攻击行为进行研究,采用目标动物取样法、随机取样法和连续记录法记录行为,探讨有效性比对雄性黄山短尾猴交配竞争的影响。研究期间,YA1群的有效性比为0.4:1,YA2群的有效性比为0.9:1,YA2群的有效性比大于YA1群。在繁殖行为上,高顺位成年雄性的性检查、做鬼脸、性追赶和交配行为在两群间均存在显著差异,YA1群高于YA2群(P<0.01);中等顺位成年雄性的性检查、做鬼脸、性追赶在两群间均存在显著差异,YA1群高于YA2群(P<0.01),交配行为在两群间存在显著差异,YA1群高于YA2群(P<0.05);低顺位成年雄性在两群间不存在显著差异。在攻击行为上,高顺位成年雄性在两群间存在显著差异,YA2群高于YA1群(P<0.01);中等顺位成年雄性在两群间存在显著差异,YA2群高于YA1群(P<0.05);YA1群低顺位成年雄性攻击行为发生频次为零。结果表明,雄雌有效性比越大,雄性黄山短尾猴的交配机会越少,繁殖行为发生频次下降,竞争压力增大,攻击行为频次上升,因此YA2群成年雄性交配竞争强度高于YA1群。本研究结果支持性选择理论中有效性比对交配竞争作用的预测。展开更多
文摘Although seasonal breeding has been documented in many non-human primates, it is not clear whether sexual behaviors show seasonal variation among male individuals. To test this hypothesis, the focal animal sampling method and continuous recording were used to investigate seasonal variation and synchronization of sexual behaviors in five male Tibetan macaques （Macaca thibetana） at Mt. Huangshan from Oct 2005 to Sept 2006. Both copulatory and sexually motivated behaviors （i.e., sexual chase, grimace, and sexual-inspection）, which were significantly higher in the mating season than non-mating season. Furthermore, seasonal variations of sexual behaviors, including copulatory and sexually motivated behaviors, were synchronized among males. The results shed light on sexual competition and tactics for reproductive success of male M. thibetana and other non-human primates with seasonal breeding.
基金supported by the National Science Foundation of China(31172106,31372215)the Program of University Innovation Team of Anhui Province(TD200703)+1 种基金the Specialized Research Fund for the Master’s Program of Higher Education(01001770-10117700618)the Science Foundation of Anhui Province(1408085QC56)
文摘Self-directed behavior(SDB) is characterized as an indicator of anxiety, frustration and stress in nonhuman primates. In this study, we collected self-directed behavior data from one group of free-ranging Tibetan macaques(Macaca thibetana) at Mt. Huangshan, China(September 2012–May 2013) using a combination of behavioral sampling methods including focal animal sampling, behavioral sampling, continuous sampling and instantaneous sampling. Our results showed that females engaged in significantly higher rates of self-directed behavior when they were in proximity to dominant individuals compared to subordinate ones. Conflict losers significantly increased their SDB rates after agonistic episodes, indicating that SDB might also serve as an index of anxiety in M. thibetana. We further found that females significantly increased their SDB rates when focal individual was proximity to weakly affiliation relationship higher rank members than to strongly affiliation relationship higher rank members. If conflicts were not reconciled, the postconflict SDB rates of losers were higher when they stayed with strongly affiliation opponents; if conflicts were reconciled, victims of strongly affiliation relationships opponents engaged in more SDB rates before reconciliation than after reconciliation, while victims of moderately affiliation relationships opponents did not engaged in more SDB rates before reconciliation than after reconciliation. We conclude that both of dominance rank and affiliation relationships might both influence the SDB rates of female Tibetan macaques significantly, suggesting that SDB is not only an index of anxiety in Tibetan macaques, but also can provide a new insight into evaluation of social relationships between individuals.
基金supported in part by grants from the National Natural Science Foundation of China(31772475 31672307+1 种基金31401981 31372215)
文摘In some non-human primates, infants function as a social tool that can bridge relationships among group members. Infants are a desired commodity for group members, and mothers control access to them. The biological market theory suggests that grooming is widespread and represents a commodity that can be exchanged for infant handling. As a limited resource, however, the extent to which infants are interchanged between mothers(females with an infant) and non-mothers(potential handlers,females without an infant) remains unclear. In this study, we collected behavioral data to investigate the relationship between grooming and infant handling in free-ranging Tibetan macaques(Macaca thibetana)at Mt. Huangshan, China. Our results showed that females with infants received more grooming than females without infants. After her infant was handled,mother females received more grooming than they did during daily grooming interactions. However, with the increasing number of infants within the social group, both the grooming that mothers received and the grooming that non-mothers invested for handling infants decreased. We also found that non-mothers invested more time in grooming to gain access to younger infants than older infants. Our results provide evidence that infants are social commodities for both mother and non-mother females. Mothers use infants for obtain grooming and non-mothers use grooming to gain access to infants. The current study implies a bidirectional and complex interchange pattern between grooming and infant handling to compensate for the dyadic grooming disparity in non-human primates.
基金funded by the National Natural Science Foundation of China (No.30570237)Outstanding Youth Foundation of Anhui (No.040443070)+1 种基金Technological Innovation team of Anhui Education Bureau (TD200703)Talent Development Foundation of Anhui, Academic Innovation team of Anhui University
文摘Though females are generally more selective in mate choice, males may also benefit from mate choice if male reproductive success is limited by factors other than simply the number of female mates, and if females differ in short-term reproductive potential. We studied male mate choice in a free-ranging troop of Tibetan macaques Macaca thibetana at Mt. Huangshan, China, from August 2007 to April 2008. We employed focal animal sampling and all occurrence sampling to record sexual related behaviors. Eight adult females were divided into three female quality categories according to the females＇ age, rank and parity. Using male mating effort as a proxy for male mate choice, we found that males do distinguish female quality and show time-variant mating strategies. Specifically, females with dominant rank, high fecundity, and middle age attracted significantly more males. Our results suggest that female short-term reproductive potential appears to be an important variable in determining male mating effort. Male Tibetan macaques do exercise mate choice for higher quality females as well as reduce useless reproductive cost, which is consistent with the direct benefits theory of mate choice.
基金supported by the State Key Program of National Natural Science Foundation of China(31530068)National Natural Science Foundation of China(31770415)Sichuan Application Foundation Project(2015JY0268)
文摘The Tibetan macaque, which is endemic to China, is currently listed as a Near Endangered primate species by the International Union for Conservation of Nature （IUCN）（2017）. Short tandem repeats （STRs） refer to repetitive elements of genome sequence that range in length from 1-6 bp. They are found in many organisms and are widely applied in population genetic studies. To clarify the distribution characteristics of genome-wide STRs and understand their variation among Tibetan macaques, we conducted a genome-wide survey of STRs with next-generation sequencing of five macaque samples. A total of 1 077 790 perfect STRs were mined from our assembly, with an N50 of 4 966 bp. Mono-nucleotide repeats were the most abundant, followed by tetra- and di-nucleotide repeats. Analysis of GC content and repeats showed consistent results with other macaques. Furthermore, using STR analysis software （IobSTR）, we found that the proportion of base pair deletions in the STRs was greater than that of insertions in the five Tibetan macaque individuals （P〈0.05, t-test）. We also found a greater number of homozygous STRs than heterozygous STRs （P〈0.05, t-test）, with the Emei and Jianyang Tibetan macaques showing more heterozygous loci than Huangshan Tibetan macaques. The proportion of insertions and mean variation of alleles in the Emei and Jianyang individuals were slightly higher than those in the Huangshan individuals, thus revealing differences in STR allele size between the two populations The polymorphic STR loci identified based on the reference genome showed good amplification efficiency and could be used to study population genetics in Tibetan macaques. The neighbor-joining tree classified the five macaques into two different branches according to their geographical origin, indicating high genetic differentiation between the Huangshan and Sichuan populations. We elucidated the distribution characteristics of STRs in the Tibetan macaque genome and provided an effective method for screening polymorphic STRs. Our results also lay a foundation for future genetic variation studies of macaques.
基金This work was funded by the Natural Science Foundation of China(Grant No.31801983,31971404,31772475,31372215)the Initial Foundation of Doctoral Scientific Research(Y040418135)the Program of Outstanding Young Teachers Training(Z010139011)in Anhui University,and China Scholarship Council.R.C.K.'s effort was supported in part by the Office of Research Infrastructure Programs(ORIP)of the National Institutes of Health(NIH)through Grant Number P5IODO 10425 to the Washington National Primate Research Center.
文摘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.
文摘有效性比(operational sex ratio,OSR)是指性成熟雄性数量与发情雌性数量的比值,可作为测量性选择强度的指标。本文对两种有效性比的黄山短尾猴(Macaca thibetana)鱼鳞坑YA1群和YA2群成年雄性在交配期(2007年8—12月)内的繁殖行为和攻击行为进行研究,采用目标动物取样法、随机取样法和连续记录法记录行为,探讨有效性比对雄性黄山短尾猴交配竞争的影响。研究期间,YA1群的有效性比为0.4:1,YA2群的有效性比为0.9:1,YA2群的有效性比大于YA1群。在繁殖行为上,高顺位成年雄性的性检查、做鬼脸、性追赶和交配行为在两群间均存在显著差异,YA1群高于YA2群(P<0.01);中等顺位成年雄性的性检查、做鬼脸、性追赶在两群间均存在显著差异,YA1群高于YA2群(P<0.01),交配行为在两群间存在显著差异,YA1群高于YA2群(P<0.05);低顺位成年雄性在两群间不存在显著差异。在攻击行为上,高顺位成年雄性在两群间存在显著差异,YA2群高于YA1群(P<0.01);中等顺位成年雄性在两群间存在显著差异,YA2群高于YA1群(P<0.05);YA1群低顺位成年雄性攻击行为发生频次为零。结果表明,雄雌有效性比越大,雄性黄山短尾猴的交配机会越少,繁殖行为发生频次下降,竞争压力增大,攻击行为频次上升,因此YA2群成年雄性交配竞争强度高于YA1群。本研究结果支持性选择理论中有效性比对交配竞争作用的预测。
