アフリカにおける人間の起源の 構造が弱い幹
Aaron P Ragsdale1, Timothy D Weaver2, Elizabeth G Atkinson3
1Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI, USA.
Nature
|May 17, 2023
まとめ
アフリカにおける人間の起源は 古代のヒトの貢献ではなく 祖先の集団間の複雑な遺伝子の流れに関係しています このネットワーク化された歴史は 海洋同位体第5段階まで遡り 現代人の遺伝的多様性を形作りました
科学分野:
- 人間 の 進化
- 人口遺伝学
- 古人類学
背景:
- ホモ・サピエンスのアフリカ起源は認められているが,特定の多様性と移住モデルは不確実である.
- 限られた化石とゲノムデータと 変動する時間差の推定は 初期の人類の歴史を理解する過程を妨げています
研究 の 目的:
- アフリカの様々な人口多様性と移住モデルを区別する.
- 先進的な統計的方法と新たに配列化されたホーサンゲノムを使って 詳細な人口史を推測する.
主な方法:
- 複雑な人口推論のためにリンクの不均衡と多様性に基づく統計を用いた.
- 南アフリカから44人のナマ (Khoe-San) の全ゲノムをシーケンスしました
- アフリカの人口の推論された網状人口史モデル.
主要な成果:
- 海の同位体レベル5まで遡る ネットワーク化されたアフリカ人口の歴史を推測した
- 現代の集団の最も初期の分岐は 12万〜13万5千年前に発生し,その前に弱分化した祖先のホモ集団の間の遺伝子フローがあった.
- 弱い構造の幹モデルは,ポリモルフィズムパターンを説明し,以前の古典的なヒトの内向性仮説に挑戦します.
結論:
- 古代の侵入ではなく 初期の遺伝子フローによる ネットワーク化された人口の歴史は アフリカの人口構造と 遺伝的多様性を最もよく説明します
- モデルの不正確な仕様は,以前の時間差の推定値の変動を反映しています.
- 深い人類の歴史に関する 堅固な推論には 多様な人口モデルの研究が必要である.
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