Inferring the demographic history of African farmers and pygmy hunter-gatherers using a multilocus resequencing data set.
Inferring the demographic history of African farmers and pygmy hunter-gatherers using a multilocus resequencing data set.
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DOI：
10.1371/journal.pgen.1000448
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发表时间：
2009-04
期刊：
影响因子：
4.5
通讯作者：
Quintana-Murci L
中科院分区：
文献类型：
--
作者：
Patin E;Laval G;Barreiro LB;Salas A;Semino O;Santachiara-Benerecetti S;Kidd KK;Kidd JR;Van der Veen L;Hombert JM;Gessain A;Froment A;Bahuchet S;Heyer E;Quintana-Murci L
从狩猎采集向农耕的转变涉及一项重大的文化创新，在过去的一万年里，这一创新在全球大部分地区迅速传播。在撒哈拉以南非洲，狩猎采集者在过去的5000年里已经开始向以农业为基础的生活方式转变。只有少数人群仍然以狩猎采集作为生存模式。俾格米人被认为是非洲最大的流动狩猎采集群体。他们居住在赤道雨林中，其特征是平均身材矮小。然而，对于最终形成当代俾格米（西部和东部）群体以及邻近农业人口的人口事件（规模变化、人口分裂和基因流动）的年代顺序，我们知之甚少。我们研究了非洲俾格米狩猎采集者和农业人口的分支历史，并估计了这些人口之间的分离时间和基因流动情况。我们对来自非洲大陆七个俾格米群体和五个农业群体的236个样本的基因组中的24个独立非编码区域进行了重测序，每个个体对应的区域总计约33kb。我们使用基于模拟的推断来确定最符合我们数据的历史模型。所确定的模型包括约60000年前俾格米狩猎采集者和农耕人口的祖先早期分化，随后约20000年前俾格米人的祖先分裂为西部和东部俾格米群体。我们的研究结果增加了对缺乏考古数据地区的非洲大陆人类居住历史的了解。了解具有不同生存模式的非洲人口的人口和适应历史，应该会提高我们对人类生活方式对基因组多样性影响的理解。
中非地带是理解人类历史和生存模式近期变化的关键区域，因为非洲最大的狩猎采集群体俾格米人仍然居住在这一地区，并与邻近的农业人口共存。然而，对赤道非洲人类居住历史的理解因雨林酸性土壤中化石遗迹的快速分解而受阻。当考古学无能为力时，群体遗传学可以从当今的基因变异中重建群体历史。我们在分布于非洲大陆的不同农业群体、西部俾格米群体和东部俾格米群体中生成了一个大型重测序数据集。通过基于模拟的推断，我们表明俾格米狩猎采集者和农耕人口的祖先大约在60000年前开始分化。这表明大约5000年前在非洲发生的向农业的转变并不是现代俾格米人和农民的祖先分离的原因。我们还表明，西部和东部俾格米群体大约在20000年前从一个共同的祖先群体中分离出来。这一发现表明，俾格米人共有的身体和文化特征是从一个共同祖先那里继承而来的，而不是反映了对雨林的趋同适应。
The transition from hunting and gathering to farming involved a major cultural innovation that has spread rapidly over most of the globe in the last ten millennia. In sub-Saharan Africa, hunter–gatherers have begun to shift toward an agriculture-based lifestyle over the last 5,000 years. Only a few populations still base their mode of subsistence on hunting and gathering. The Pygmies are considered to be the largest group of mobile hunter–gatherers of Africa. They dwell in equatorial rainforests and are characterized by their short mean stature. However, little is known about the chronology of the demographic events—size changes, population splits, and gene flow—ultimately giving rise to contemporary Pygmy (Western and Eastern) groups and neighboring agricultural populations. We studied the branching history of Pygmy hunter–gatherers and agricultural populations from Africa and estimated separation times and gene flow between these populations. We resequenced 24 independent noncoding regions across the genome, corresponding to a total of ∼33 kb per individual, in 236 samples from seven Pygmy and five agricultural populations dispersed over the African continent. We used simulation-based inference to identify the historical model best fitting our data. The model identified included the early divergence of the ancestors of Pygmy hunter–gatherers and farming populations ∼60,000 years ago, followed by a split of the Pygmies' ancestors into the Western and Eastern Pygmy groups ∼20,000 years ago. Our findings increase knowledge of the history of the peopling of the African continent in a region lacking archaeological data. An appreciation of the demographic and adaptive history of African populations with different modes of subsistence should improve our understanding of the influence of human lifestyles on genome diversity. The central African belt represents a key region for understanding recent changes in human history and modes of subsistence because the largest group of hunter–gatherers of Africa, the Pygmies, still inhabits this region and coexists with neighboring agricultural populations. However, the understanding of the peopling history of equatorial Africa is hampered by the rapid disintegration of fossil remains in the rainforest's acidic soils. When archaeology fails, population genetics can reconstruct the history of populations from their present-day genetic variation. We generated a large resequencing dataset in different farming, Western Pygmy, and Eastern Pygmy populations dispersed over the African continent. By means of simulation-based inferences, we show that the ancestors of Pygmy hunter–gatherers and farming populations started to diverge ∼60,000 years ago. This indicates that the transition to agriculture—occurring in Africa ∼5,000 years ago—was not responsible for the separation of the ancestors of modern-day Pygmies and farmers. We also show that Western and Eastern Pygmy groups separated roughly 20,000 years ago from a common ancestral population. This finding suggests that the shared physical and cultural features of Pygmies were inherited from a common ancestor, rather than reflecting convergent adaptation to the rainforest.
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DOI：
10.3406/bmsap.1993.2371
发表时间：
1993-01-01
影响因子：
--
作者：
Froment, Alain
通讯作者：
Froment, Alain
影响因子：
9.8
作者：
Behar, Doron M.;Villems, Richard;Rosset, Saharon
通讯作者：
Rosset, Saharon
DOI：
10.1073/pnas.0611164104
发表时间：
2007-02-20
影响因子：
11.1
作者：
Hey, Jody;Nielsen, Rasmus
通讯作者：
Nielsen, Rasmus
DOI：
10.1073/pnas.96.19.10597
发表时间：
1999-09-14
影响因子：
11.1
作者：
Excoffier, L;Schneider, S
通讯作者：
Schneider, S
影响因子：
64.8
作者：
Ingman, M;Kaessmann, H;Gyllensten, U
通讯作者：
Gyllensten, U