深い人類の系譜は,拡大する波のフロントに立つという選択的優位性を明らかにしている
Claudia Moreau1, Claude Bhérer, Hélène Vézina
1Centre de Recherche, Hôpital Sainte-Justine, Université de Montréal, 3175 Côte Sainte-Catherine, Montréal, Québec, Canada.
Science (New York, N.Y.)
|November 5, 2011
まとめ
人口拡大のダイナミクスは,拡大する範囲のフロントの祖先が遺伝子プールにより多く貢献したことを明らかにします. これは,波の先にある女性におけるより高い生育率と関連しており,これは遺伝的特徴である.
科学分野:
- 集団遺伝学 人口遺伝学
- 人間の進化 人類の進化
- 人口統計の歴史 人口統計の歴史
背景:
- 世界中の人間の植民地化は,複雑な人口統計的プロセスを伴う.
- 集団の範囲拡大の原動力を理解することは,進化生物学における重要な課題です.
研究 の 目的:
- 人間の範囲の拡大を左右する人口学的プロセスを調査する.
- ケベック州の歴史的な人口拡大の空間的および遺伝的動態を再構築する.
主な方法:
- 100万人以上の個体からの遺伝学データの分析.
- 歴史的な人口統計データを用いて空間拡大の動態を再構築する.
- 近代的な遺伝子プールへの祖先の貢献を,位置 (範囲前面対コア) に基づいて比較する.
主要な成果:
- 現在のサギネイ・ラック・サン・ジャンの人口の大部分は,膨張の波の前線の祖先からの子孫である.
- 範囲の先端の祖先は,現在の遺伝子プールに不釣り合いにもっと貢献しました.
- 波の最前線にいる女性は,遺伝的な特徴である実質的な生育能力が約20%高いことを示した.
結論:
- 生育力などの生命史の特徴は,範囲の拡大の間に進化する.
- 拡張前線に対する空間的位置は,遺伝子プールへの先祖の貢献に大きく影響する.
- 集団の遺伝的多様性を形作る上で,範囲前部の人口学的プロセスは決定的な役割を果たします.
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