中文摘要：

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。

英文摘要：

Operational sex ratio （OSR） is the ratio of the number of sexually mature males to the estrous females, which is used to predict the intensity of sexual selection. During the mating season （August-December 2007）, we studied reproductive and aggressive behaviors in sexually mature male Tibetan macaques （Macaca thibitana） in two troops （YA1 and YA2） at Huangshan, China. The behavioral data were collected by focal animal sampling, ad libitum sampling and continuous recording. The purpose is to discuss the impact of OSR on mating competition of male Tibetan macaques. The OSR of YA1 was 0.4：1, and the OSR of YA2 was 0.9：1. The male-biased in OSR of YA2 was higher than YA1 The sexually mature males of high rank in YA1 troop showed higher rates of reproductive behaviors than the males in YA2： genital-inspecting, grimace, sexual chase and mating, respectively （P〈0.01）. The sexually mature males of middle rank in YA1 troop showed higher rates of reproductive behaviors than the males in YA2： genital-inspecting, grimace, sexual chase （P〈0.01）. The sexually mature males of middle rank in YA1 troop also showed higher rate of mating behavior than the males in YA2 （P〈0.05）. However, there was no significant difference in reproductive behaviors between sexually mature males of low rank in two troops. The sexually mature males of high rank in YA2 troop showed higher rate of aggressive behavior than the males in YA1 （P〈0.01）. The sexually mature males of middle rank in YA2 troop showed higher rate of aggressive behavior than the males in YA1 （P〈0.05）. The sexually mature males of low rank in YA1 troop didn＇t show any aggressive behavior. These results suggested that the intensification of male-biased in OSR can lead to the decrease of reproductive behaviors and the increase of aggressive behavior of male Tibetan macaques. The intensity of mating competition of sexually mature males in YA2 troop was stronger than the males in YA1. Our results support the prediction of the impa