実験的な細菌集団における協力と対立の進化
Paul B Rainey1, Katrina Rainey
1Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK. p.rainey@auckland.ac.nz
Nature
|September 5, 2003
まとめ
多細胞性への進化的移行は容易に達成可能である. Pseudomonas fluorescensにおける実験的協力は,費用のかかる個々の協力がグループに利益をもたらすことを示したが,脱走者が現れる可能性がある.
科学分野:
- 進化生物学の進化生物学について
- 微生物学 微生物学とは
背景:
- 単細胞生物から多細胞生物への進化的移行は,生物学の根本的な問題である.
- この移行の間,選択の単位は個々の細胞から協力するグループに移行する.
- 広範な理論的研究にもかかわらず,この移行に関する経験的研究はほとんどありません.
研究 の 目的:
- 多細胞性への経験的進化的移行を記述し,分析する.
- 実験集団における協力,脱退,集団利益のダイナミクスを調査する.
- 個性の進化を促す条件を評価する.
主な方法:
- 空間的に異質な環境でPseudomonas fluorescensの実験集団を利用した.
- ポリマーの過剰生産による協力のコストと利益の分析.
- 協力グループ内の脱走型遺伝子の進化と適性を研究する.
主要な成果:
- 粘着性ポリマーの過剰生産によって形成された協力グループは,個人とグループの利益を一致させました.
- 協力は個人にコストを負わせたが,グループに利益をもたらした.
- 脱走したゲノタイプは進化し,協力者の存在により適格になり,当初はグループの生存能力を阻害しました.
結論:
- より高度な複雑性への進化的移行は,実験的条件下では達成可能である.
- この研究は,多細胞性を誘発する選択的条件についての洞察を提供します.
- この発見は,個性の進化の実験的分析を容易にする.
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