Simonsen B T, Siegismund H R, Arctander P
Department of Population Biology, University of Copenhagen, Denmark.
Mol Ecol. 1998 Feb;7(2):225-37. doi: 10.1046/j.1365-294x.1998.00343.x.
The African buffalo (Syncerus caffer) is widespread throughout sub-Saharan Africa and is found in most major vegetation types, wherever permanent sources of water are available, making it physically able to disperse through a wide range of habitats. Despite this, the buffalo has been assumed to be strongly philopatric and to form large aggregations that remain within separate home ranges with little interchange between units, but the level of differentiation within the species is unknown. Genetic differences between populations were assessed using mitochondrial DNA (control region) sequence data and analysis of variation at six microsatellite loci among 11 localities in eastern and southern Africa. High levels of genetic variability were found, suggesting that reported severe population bottlenecks due to outbreak of rinderpest during the last century did not strongly reduce the genetic variability within the species. The high level of genetic variation within the species was found to be evenly distributed among populations and only at the continental level were we able to consistently detect significant differentiation, contrasting with the assumed philopatric behaviour of the buffalo. Results of mtDNA and microsatellite data were found to be congruent, disagreeing with the alleged male-biased dispersal. We propose that the observed pattern of the distribution of genetic variation between buffalo populations at the regional level can be caused by fragmentation of a previous panmictic population due to human activity, and at the continental level, reflects an effect of geographical distance between populations.
非洲水牛（非洲野水牛属）广泛分布于撒哈拉以南非洲地区，在大多数主要植被类型中都能找到，只要有永久性水源，这使其能够在广泛的栖息地中扩散。尽管如此，人们一直认为水牛具有强烈的恋巢性，会形成大型群体，这些群体留在各自独立的活动范围内，不同群体之间很少有交流，但该物种内部的分化程度尚不清楚。利用线粒体DNA（控制区）序列数据以及对非洲东部和南部11个地点的6个微卫星位点的变异分析，评估了不同种群之间的遗传差异。研究发现存在高水平的遗传变异性，这表明上世纪因牛瘟爆发导致的严重种群瓶颈并未强烈降低该物种内部的遗传变异性。该物种内部的高水平遗传变异在各群体中均匀分布，只有在大陆层面我们才能持续检测到显著的分化，这与水牛被认为的恋巢行为形成对比。线粒体DNA和微卫星数据的结果是一致的，与所谓的雄性偏向扩散不一致。我们认为，在区域层面观察到的水牛种群间遗传变异分布模式可能是由于人类活动导致先前的随机交配种群碎片化造成的，而在大陆层面，则反映了种群之间地理距离的影响。
