中文摘要：

动物集群的群体行为决策是营集群生活的动物调节其群体活动、而获得集群生活收益的重要手段。受动物自身行为和需求的影响，动物集群的群体决策有不同的外在表现形式和过程。本研究以青海湖湖东地区的普氏原羚种群为对象，于2010年3月至2012年3月对普氏原羚集群的群体决策过程进行了观察和记录，并对所得数据采用非参数检验方法进行统计与分析，分析结果表明：1．普氏原羚集群的群体决策类型为不完全民主型，需要有一定比例的个体共同参与群体决策过程才能达成群体决策，而参与群体决策的个体比例随群体规模的增加而降低；2．参与决策的个体因性别不同而有不同的表现，且在决策过程所需时间上存在差异，这可能是导致普氏原羚产生同性聚群现象的原因之一。这是在野外直接对大型有蹄类动物集群的群体决策过程进行的为数不多的研究，还需要更多的野外研究来探究不同类型动物群体决策过程及其与同性聚群产生机理之间的关系。

英文摘要：

Group decision-making is one of the important methods to coordinate the behavior of individual animals living in a group in order to achieve the benefits of group-living. However, the types and processes of group decision-making are dif- ferent among different animals due to their differences in behavior and demands. In this study, we observed the group deci- sion-making processes of a population of group-living Przewalski＇ s gazelles （Procapra przewalskii） in Hudong-Ketu area a- round Qinghaihu Lake from March 2010 to March 2012, and the data were analysed by using the method of nonparametric tests. The group decision-making in Przewalski＇ s gazelle was found to be partially democratic decision-making process, in which a proportion of individuals （ 〉 46. 3% ） was required to reach agreement for a group decision. The proportion of the individuals participating in group decision-making processes decreased with group size （for female groups ： r = O. 552, P 〈 0. 001 ; for male groups ： r = - 0. 524, P 〈 O. 001 ）. The time needed to make a group decision was different among male groups, female groups, and nurture groups （Kruskal -Wallis Test, X2 = 19. 362, df= 2, P 〈 0. 001 ）, which may have re- sulted in sexual segregation in Przewalski＇ s gazelle. This study is a pioneer experiment to explore the mechanism and process of big mammal＇ s group decision-making in the field, and more studies are needed to investigate group decision- making processes and their relation to sexual segregation in animals in the future.