Department of Animal Sciences, University of Illinois at Urbana-Champaign Urbana, IL, USA.
Evol Appl. 2013 Feb;6(2):253-65. doi: 10.1111/j.1752-4571.2012.00286.x. Epub 2012 Aug 1.
African elephant mitochondrial (mt) DNA follows a distinctive evolutionary trajectory. As females do not migrate between elephant herds, mtDNA exhibits low geographic dispersal. We therefore examined the effectiveness of mtDNA for assigning the provenance of African elephants (or their ivory). For 653 savanna and forest elephants from 22 localities in 13 countries, 4258 bp of mtDNA was sequenced. We detected eight mtDNA subclades, of which seven had regionally restricted distributions. Among 108 unique haplotypes identified, 72% were found at only one locality and 84% were country specific, while 44% of individuals carried a haplotype detected only at their sampling locality. We combined 316 bp of our control region sequences with those generated by previous trans-national surveys of African elephants. Among 101 unique control region haplotypes detected in African elephants across 81 locations in 22 countries, 62% were present in only a single country. Applying our mtDNA results to a previous microsatellite-based assignment study would improve estimates of the provenance of elephants in 115 of 122 mis-assigned cases. Nuclear partitioning followed species boundaries and not mtDNA subclade boundaries. For taxa such as elephants in which nuclear and mtDNA markers differ in phylogeography, combining the two markers can triangulate the origins of confiscated wildlife products.
非洲象的线粒体 (mt) DNA 遵循独特的进化轨迹。由于雌性大象不会在象群之间迁徙,因此 mtDNA 的地理扩散程度较低。因此,我们研究了 mtDNA 在确定非洲象(或其象牙)来源方面的有效性。我们对来自 13 个国家 22 个地点的 653 头草原象和森林象进行了测序,共 4258 个碱基对。我们检测到 8 个 mtDNA 亚群,其中 7 个具有区域性限制分布。在所鉴定的 108 个独特单倍型中,72%仅在一个地点发现,84%是特定于国家的,而 44%的个体携带仅在其采样地点发现的单倍型。我们将控制区的 316 个碱基对与以前对非洲象进行的跨国调查生成的序列相结合。在来自 22 个国家 81 个地点的 101 个独特的非洲象控制区单倍型中,62%仅存在于一个国家。将我们的 mtDNA 结果应用于以前基于微卫星的分配研究中,可以改善 122 个错误分配案例中的 115 个案例中大象来源的估计。核分离遵循物种边界,而不是 mtDNA 亚群边界。对于象类等核和 mtDNA 标记在系统地理学上存在差异的分类群,结合这两种标记可以确定没收的野生生物产品的起源。