6万世代に渡る 分子進化の動態
Benjamin H Good1,2,3,4,5, Michael J McDonald1,2,6, Jeffrey E Barrick7,8
1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Nature
|October 19, 2017
まとめ
進化の動態は6万世代に渡ってエシェリキア・コレで研究された. 身体能力が低下したにもかかわらず 急速な適応と競合する変種が観察され 複雑な進化過程が明らかになった.
科学分野:
- 進化生物学
- 微生物の進化
- ゲノミクス
背景:
- 進化の成果は変異のダイナミクスに依存している.
- ゲノム進化の長期観察は 難しいものです
研究 の 目的:
- 実験集団における分子進化の動態を分析する.
- 長期にわたる適応と ゲノム全体を調査する
主な方法:
- 12のエシェリキア・コライ集団の全ゲノムメタゲノムシーケンシング
- 500世代間隔で6万世代でサンプリングする
主要な成果:
- 迅速な適応のサインは 実験中ずっと続きました
- 複数の有利なバリエーションが同時に競争した.
- 生態系と進化の相互作用により クラードが共存し 進化が続きました
- エピスタシスと歴史的偶然性により 選択のターゲットが 時間の経過とともに変化した.
結論:
- 恒常的な環境における長期的適応は複雑でダイナミックです
- 自然選択の標的は 適応の過程で変化する
- ストカスティックなプロセスと生態学的相互作用が 進化の軌道を形作ります
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