Muwanika V B, Nyakaana S, Siegismund H R, Arctander P
Institute of Environment and Natural Resources, Makerere University, PO Box 7298, Kampala, Uganda.
Heredity (Edinb). 2003 Oct;91(4):361-72. doi: 10.1038/sj.hdy.6800341.
Global climate fluctuated considerably throughout the Pliocene and Pleistocene, influencing the evolutionary history of a wide range of species. Using both mitochondrial sequences and microsatellites, we have investigated the evolutionary consequences of such environmental fluctuation for the patterns of genetic variation in the common warthog, sampled from 24 localities in Africa. In the sample of 181 individuals, 70 mitochondrial DNA haplotypes were identified and an overall nucleotide diversity of 4.0% was observed. The haplotypes cluster in three well-differentiated clades (estimated net sequence divergence of 3.1-6.6%) corresponding to the geographical origins of individuals (i.e. eastern, western and southern African clades). At the microsatellite loci, high polymorphism was observed both in the number of alleles per locus (6-21), and in the gene diversity (in each population 0.59-0.80). Analysis of population differentiation indicates greater subdivision at the mitochondrial loci (FST=0.85) than at nuclear loci (FST=0.20), but both mitochondrial and nuclear loci support the existence of the three warthog lineages. We interpret our results in terms of the large-scale climatic fluctuations of the Pleistocene.
在整个上新世和更新世期间，全球气候波动剧烈，影响了众多物种的进化历程。我们利用线粒体序列和微卫星，研究了这种环境波动对非洲疣猪遗传变异模式的进化影响，样本来自非洲的24个地点。在181个个体的样本中，共鉴定出70种线粒体DNA单倍型，总体核苷酸多样性为4.0%。这些单倍型聚为三个分化明显的分支（估计净序列分歧为3.1 - 6.6%），分别对应个体的地理起源（即东非、西非和南非分支）。在微卫星位点上，每个位点的等位基因数量（6 - 21个）和基因多样性（每个种群为0.59 - 0.80）都显示出高度多态性。种群分化分析表明，线粒体位点的分化程度（FST = 0.85）高于核位点（FST = 0.20），但线粒体和核位点均支持存在三个疣猪谱系。我们根据更新世的大规模气候波动来解释我们的研究结果。
