群居性啮齿动物集群重组率的估算

提出了一种定量估算群居性啮齿动物的集群重组率的方法。此法以特定时期集群中动物个体之间的异源概率（即来源于不同家族的概率）作为衡量群居性啮齿动物的“混合”程度（即重组率）的定量指标，并与平均重组率（即重组期望）进行比较，进而判断动物在集群过程中的选择倾向。按照这种方法估算了内蒙古典型草原区布氏田鼠越冬集群的重组率。结果表明，该鼠的越冬集群重组率很低，仅在0.1左右，集群个体多数来源于相同的家族。此外，该鼠的集群重组率远低于其重组期望值，表明该鼠在秋季集群中，有强烈的选择同源个体的倾向。

ESTIMATING THE GROUP REFORMATIVE RATE FOR SOCIAL RODENT SPECIES

A new procedure is proposed to estimate the group reformativerate of the group unit(s) for the social rodent species. The probability that two animals taken randomly from a group come from different original groups is used as a measurement of group reformative rate at a census. Moreover, the expected group informative rate is also derived as an index to evaluate the preference during the regrouping period. An illustration of how to apply this method to estimate the group reformative rate of the communal over-winter nests of Brandt's vole in the typical steppe in Inner Mongolia grassland. Results revealed that the over-winter group reformative rate of this species is very low, suggesting that many members of the same over-winter group came from the same family. Furthermore, the group reformative rate is much lower than the expected group reformative rate, which indicates that the Brandt's vole possess a high preference to select familiar individuals as group members during this period.