Hunley Keith, Dunn Michael, Lindström Eva, Reesink Ger, Terrill Angela, Healy Meghan E, Koki George, Friedlaender Françoise R, Friedlaender Jonathan S
Department of Anthropology, University of New Mexico, Albuquerque, NM, USA.
PLoS Genet. 2008 Oct;4(10):e1000239. doi: 10.1371/journal.pgen.1000239. Epub 2008 Oct 31.
Recent studies have detailed a remarkable degree of genetic and linguistic diversity in Northern Island Melanesia. Here we utilize that diversity to examine two models of genetic and linguistic coevolution. The first model predicts that genetic and linguistic correspondences formed following population splits and isolation at the time of early range expansions into the region. The second is analogous to the genetic model of isolation by distance, and it predicts that genetic and linguistic correspondences formed through continuing genetic and linguistic exchange between neighboring populations. We tested the predictions of the two models by comparing observed and simulated patterns of genetic variation, genetic and linguistic trees, and matrices of genetic, linguistic, and geographic distances. The data consist of 751 autosomal microsatellites and 108 structural linguistic features collected from 33 Northern Island Melanesian populations. The results of the tests indicate that linguistic and genetic exchange have erased any evidence of a splitting and isolation process that might have occurred early in the settlement history of the region. The correlation patterns are also inconsistent with the predictions of the isolation by distance coevolutionary process in the larger Northern Island Melanesian region, but there is strong evidence for the process in the rugged interior of the largest island in the region (New Britain). There we found some of the strongest recorded correlations between genetic, linguistic, and geographic distances. We also found that, throughout the region, linguistic features have generally been less likely to diffuse across population boundaries than genes. The results from our study, based on exceptionally fine-grained data, show that local genetic and linguistic exchange are likely to obscure evidence of the early history of a region, and that language barriers do not particularly hinder genetic exchange. In contrast, global patterns may emphasize more ancient demographic events, including population splits associated with the early colonization of major world regions.
近期研究详细阐述了北岛美拉尼西亚地区显著的遗传和语言多样性。在此，我们利用这种多样性来检验两种遗传与语言共同进化的模型。第一种模型预测，遗传和语言的对应关系是在早期向该地区扩张范围时种群分裂和隔离之后形成的。第二种模型类似于距离隔离的遗传模型，它预测遗传和语言的对应关系是通过相邻种群之间持续的遗传和语言交流形成的。我们通过比较观察到的和模拟的遗传变异模式、遗传和语言树以及遗传、语言和地理距离矩阵，来检验这两种模型的预测。数据包括从33个北岛美拉尼西亚种群收集的751个常染色体微卫星和108个结构语言特征。测试结果表明，语言和遗传交流已经抹去了该地区定居历史早期可能发生的分裂和隔离过程的任何证据。在更大的北岛美拉尼西亚地区，相关模式也与距离隔离共同进化过程的预测不一致，但在该地区最大岛屿（新不列颠岛）崎岖的内陆地区，有强有力的证据支持这一过程。在那里，我们发现了遗传、语言和地理距离之间一些最强的记录相关性。我们还发现，在整个地区，语言特征通常比基因更不容易跨越种群边界扩散。基于异常精细的数据，我们的研究结果表明，局部遗传和语言交流可能会掩盖一个地区早期历史的证据，而且语言障碍并不会特别阻碍遗传交流。相比之下，全球模式可能更强调更古老的人口事件，包括与世界主要地区早期殖民化相关的种群分裂。
