ABSTRACT Geneticists have argued that the linear decay in within-population genetic diversity with increasing geographic distance from East Africa is best explained by a phylogenetic process of repeated founder effects, growth, and isolation. However, this serial founder effect (SFE) process has not yet been adequately vetted against other evolutionary processes that may also affect geospatial patterns of diversity. Additionally, studies of the SFE process have been largely based on a limited 52-population sample. In this modestly updated article, originally published in Human Biology in 2016 (vol. 88, no. 3, pp. 219–231), we assess the effects of founder effect, admixture, and localized gene flow processes on patterns of global and regional diversity using a published data set of 645 autosomal microsatellite genotypes from 5,415 individuals in 248 widespread populations. We used a formal tree-fitting approach to explore the role of founder effects. The approach involved fitting global and regional population trees to extant patterns of gene diversity and then systematically examining the deviations in fit. We also informally tested the SFE process using linear models of gene diversity versus waypoint geographic distances from Africa. We tested the role of localized gene flow using partial Mantel correlograms of gene diversity versus geographic distance controlling for the confounding effects of treelike genetic structure. We corroborate previous findings that global patterns of diversity, both within and between populations, are the product of an out-of-Africa SFE process. Within regions, however, diversity within populations is uncorrelated with geographic distance from Africa. Here, patterns of diversity have been largely shaped by recent interregional admixture and secondary range expansions. Our detailed analyses of the pattern of diversity within and between populations reveal that the signatures of different evolutionary processes dominate at different geographic scales. These findings have important implications for recent publications on the biology of race. Our new foreword situates these findings in a long line of anthropological research that categorically rejects racial interpretations of analyses of human diversity.

中文翻译：

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超越系列创始人效应：混合和本地化基因流对区域遗传多样性模式的影响

摘要 遗传学家认为，随着与东非地理距离的增加，种群内遗传多样性的线性衰减最好用重复的创始人效应、生长和隔离的系统发育过程来解释。然而，这种连续创始人效应 (SFE) 过程尚未针对其他可能影响地理空间多样性模式的进化过程进行充分审查。此外，对 SFE 过程的研究主要基于有限的 52 人样本。在这篇适度更新的文章中，最初发表于 2016 年的人类生物学（第 88 卷，第 3 期，第 219-231 页），我们评估了创始人效应、混合和本地化基因流动过程对全球和区域模式的影响多样性使用来自 5 的 645 个常染色体微卫星基因型的已发布数据集，248 个广泛的种群中的 415 个人。我们使用正式的树拟合方法来探索创始人效应的作用。该方法涉及将全球和区域人口树拟合到现有的基因多样性模式，然后系统地检查拟合偏差。我们还使用基因多样性的线性模型与与非洲的航路点地理距离进行了非正式测试 SFE 过程。我们使用基因多样性的部分 Mantel 相关图与控制树状遗传结构的混杂效应的地理距离来测试本地化基因流的作用。我们证实了先前的发现，即种群内部和种群之间的全球多样性模式是非洲外 SFE 过程的产物。然而，在区域内，种群内的多样性与与非洲的地理距离无关。在这里，多样性模式在很大程度上是由最近的区域间混合和次要范围扩展所塑造的。我们对种群内部和种群之间多样性模式的详细分析表明，不同进化过程的特征在不同的地理尺度上占主导地位。这些发现对最近关于种族生物学的出版物具有重要意义。我们的新前言将这些发现置于一长串人类学研究中，这些研究断然拒绝对人类多样性分析的种族解释。我们对种群内部和种群之间多样性模式的详细分析表明，不同进化过程的特征在不同的地理尺度上占主导地位。这些发现对最近关于种族生物学的出版物具有重要意义。我们的新前言将这些发现置于一长串人类学研究中，这些研究断然拒绝对人类多样性分析的种族解释。我们对种群内部和种群之间多样性模式的详细分析表明，不同进化过程的特征在不同的地理尺度上占主导地位。这些发现对最近关于种族生物学的出版物具有重要意义。我们的新前言将这些发现置于一长串人类学研究中，这些研究断然拒绝对人类多样性分析的种族解释。