秦岭金丝猴（Rhinopithecus roxellana）交配行为的研究

【作者】 赵大鹏；

【导师】 李保国；

【作者基本信息】 西北大学 ， 动物学， 2005， 硕士

【摘要】 第一章 秦岭金丝猴交配行为的初步研究 本研究通过656小时的焦点动物观察,基于描述秦岭周至国家自然保护区玉皇庙西梁野生川金丝猴群的性行为,并试将研究结果与笼养结果进行比较分析。结果表明:在观察到的328次交配中,雌性通常为交配的主要发起者,交配时采用腹背式姿势,交配平均持续时间为15.96±0.41s,交配后雌性主要表现出四种不同的行为:雌性慢慢离开雄性并在其不远处停下占32.32%;雌性快速离开雄性并距之以数米占27.74%;雌性为雄性理毛占27.13%;雌性与雄性拥抱占4.57%。 本研究中观察发现的雄性交配时双踩雌性脚踝的姿势尚属该研究领域内首次报道。交配行为全年发生并存在孕后交配行为;性干扰现象支持“性竞争假说”,即干扰者以降低被干扰方交配成功率或者以被干扰方未完成交配为代价试图获得自己与雄性的交配机会(Neimeyer and Anderson,1983;Hall,1965)。此外观察到未成年猴的两种性学习行为:其一是观察交配过程;其二是在社会玩耍中邀配和爬背动作的模仿。 第二章 秦岭金丝猴单元外交配行为的研究 致孕的组外交配行为在进化上具有重要意义,而且组外交配行为还涉及到其他更多的非直接利益。组外性行为在一夫一妻制灵长类和一夫多妻制的诸多灵长类中均有所报道(Palombit, 1994; Reichard, 1995; Olson, 1985; van Noordwijk, 1985; Boinski, 1987; Agoramoorthy & Mohnot, 1988; Agoramoorthy & Minna, 2000)。本项研究首次对秦岭野生川金丝猴的组外性行为,即单元外性行为进行报道。在2001年11月至2004年5月的观察期内通过行为取样法共观察到了12次单元外性行为;研究发现这种行为全年均有发生,发起者几乎全是成年或亚成年雌性,而且交配季节发生的频次明显高于非交配季节发生的频次。对于野生川金丝猴,单元外性行为的策略支持“杂合性假说”,即雌性通过选择遗传差异大的个体来增加其后代的杂合性程度。更多还原

【Abstract】 This study, based on 656 hours of focal observations, aimed to describe the sexual behavior of the wild Sichuan snub-nosed monkey {Rhinopithecus roxellana) and compare the results with previous studies on captive populations. Results found that copulation was usually initiated by female courtship, this was followed by pelvis thrust in a dorso-ventral posture, performed on the ground (83.54%), in a tree (11.89%) or on a cliff (4.57%) and continued for 15.96±0.41s. Of the 328 episodes of behaviour after copulation observed in our study, females moved unhurriedly from the male or stayed close to him 106 times (32.32%), exhibited a "copulatory dart" (i.e. the female darted several meters away from them and sat down) 91 times (27.74%), actively groomed the male 89 times (27.13%), and hugged the male 15 times (4.57%).The doubt-clasp gesture during copulation was observed in this study for the first time, this gesture was not reported in previous studies carried out on captive populations. Copulation was shown to occur at almost any stage throughout the breeding and birthing seasons, including up to a few days before parturition. Sexual interference was also observed, which we suggests supports the "sexual-competition hypothesis" i.e. the harassers reduce the mating success of copulating animals or attempt to gain future copulations at the expense of one of the mating individuals. Additionally, I observed two ways in which juveniles learnt sexual behaviour, firstly through observations of adult copulation process, and secondly through prostrating or mounting peers as a form of social play.Copulations with extra-group males are clearly important at an evolutionary level if they result in conceptions, but there can also be other, more indirect benefits involved. Extragroup sexual behavior has been reported in both monogamous primates and polygynous primates. In this paper, the extra-unit sexual behavior of Sichuan snub-nosed monkey (Rhinopithecus roxellana) was firstly studied in their natural habitat. We observed 12 times of extra-unit copulation during our observation from November 2001 to December 2003 intermittently. During my observation, the number of units within the group fluctuated from six to nine. Sampling of the sexual behavior was performed using the methodology described by Martin & Bateson (1993). Besides the extra-unit sexual behavior occurs rarely all the year and it is more frequent at the mating season than at non-mating season. The sponsor in the behavior is almost adult and subadult female. As for the monkey, the strategy of copulating with neighboring units’ male appears to support the "heterozygosity hypothesis" that females choose genetically dissimilar partners to increase the degree of heterozygosity in their offspring. Sexual behavior data was collected using focal animal sampling and a total of 733 hours of observations were recorded between March 2003 and May 2004. During this period a total of 399 copulations including 22 multiple copulations were observed. I found that the mean duration of female multiple copulations per hour were greater in themating season (19.67 ± 1.29s) than in the non-mating season (9.8 ± 2.46s) and the number of female multiple copulations per hour ranged between two and five. During the mating season both adult and sub-adult females were the main initiator of multiple copulations whereas during the non-mating season males become the primary initiator. This study has also shown that female multiple copulations occur within both the mating and the non-mating season suggesting that the purpose of this behavior is not limited to propagation. Males may use multiple copulation behavior in order to establish or cement reproductive relationships.Data was collected on the socio-sexual behavior of a free-ranging group of Sichuan snub-nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains. Mounting behavior was observed to follow male-male inter-unit conflicts in both parties. This pattern was documented across both mating and non-mating seasons. Females’ proximity to males would increase during the conflict. Intromission was rare during post inter-unit conflict mountings. The benefits of such a strategy are discussed in terms of anxiety reduction and female reproduction.更多还原