绿色撒哈拉的古老DNA揭示了祖先的北非血统
Nada Salem1,2, Marieke S van de Loosdrecht3,4, Arev Pelin Sümer3
1Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany. nada_salem@eva.mpg.de.
Nature
|April 2, 2025
概括
撒哈拉的古老DNA揭示了以前未知的北非血统, 在非洲潮湿时期传播牧民. 这种血统仍然是孤立的, 显示出来自撒哈拉以南非洲的有限基因流动.
科学领域:
- 古遗传学
- 非洲史前史
- 人类的进化
背景情况:
- 撒哈拉沙漠在非洲潮湿时期 (AHP) 从一个绿色的草原转变为目前的干旱状态.
- 对于这个地区的古代DNA数据有限, 阻碍了对它的遗传历史和人口统计的理解.
- 牧民主义在整个北非中期的全新纪,与AHP相吻合.
研究的目的:
- 分析来自中撒哈拉的古老基因组数据以重建过去的人口.
- 调查早期北非牧民的遗传起源和关系.
- 了解AHP期间北非的基因流动和人口动态.
主要方法:
- 在利比亚的塔卡尔科里岩石避难所从两名7000年前的古老DNA中提取和测序.
- 全基因组分析以确定祖先组成部分和人口关系.
- 与现有的古老和现代人类基因组数据集进行比较.
主要成果:
- 塔卡科里族的祖先来自一个新的北非血统,很早就从撒哈拉以南的群体中分离出来,并且在很大程度上孤立.
- 这种血统与来自摩洛哥的古老采集者 (Iberomaurusian工业) 密切相关,早于AHP.
- 在AHP期间,从撒哈拉以南非洲到北非的基因流量有限. 塔卡科里人与其他古代人群相比, 呈现出明显的尼安德特人混合水平.
结论:
- 牧民主义很可能通过文化传播传播到一个极为分歧的,孤立的北非人群中.
- 这种群体可能在北非普莱斯托纪晚期普遍存在.
- 这些发现揭示了北非在关键气候转变期间的遗传景观和人口历史.
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