Abstract: In order to understand the relationship between the social hierarchy and reproductive characteristic , the reproductive behavior of different social ranks of Brandt's vole was studied in laboratory during the breeding season fromMay to September of 2000. Observation of the behavior was carried out after the ninety nine adult voles in fifteen typical families were sexually confirmed , weighed , numbered by cutting toes and marked by the hair cut. The behavioral frequencies of different voles and the serial numbers of pregnant females were recorded. The detailed results of behavioral analysis were shown as follows. The competition among females for male partners was fierce. The dominant female acquired the most chances of being selected to mate with , while the subordinate female might be chosen and its hierarchy got higher. The dominant male , which may select all rank's females , has the most aggressive attacking behavior to other males in order to obtain more breeding opportunities. Based on the experimental analysis , as a result of population evolution in long period , the conclusion that Brandt's voles with high hierarchy played the most important role in social reproduction could be drawn , with agreement on the mating system of one male with females or mixed mating.

Key words: Brandt's vole (Microtus brandti), Social hierarchy, Reproductive behavior

摘要： 在实验室条件下观察了捕自内蒙古草原的不同序位布氏田鼠的繁殖行为特征。结果表明, 雌鼠对雄性配偶存在着激烈的竞争, 高序位雌鼠获得被选择、交尾及产仔的机会最多, 较低序位雌鼠若被选择并且产仔, 则其序位将随之上升; 高序位雄鼠对各个序位雌鼠均可选择, 且在繁殖期间对同性个体表现很强的攻击性, 以获得更多的交配机会。在社群繁殖中高序位雌、雄个体的作用明显高于低序位个体, 这是布氏田鼠种群长期选择进化的生存策略。实验支持了布氏田鼠为混交制、一雄多雌的婚配制度推论。

关键词: 布氏田鼠, 社群序位, 繁殖行为