競争と捕食が多様化に及ぼす影響について,適応放射線モデル
1Department of Biology and Center for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa K1N 6N5, Canada. justin.raymond.meyer@gmail.com
Nature
|March 23, 2007
まとめ
プロティストによる捕食は,資源競争と同様に細菌の多様化を促すことができるが,速度が遅い. この研究は,捕食を明らかにしています.
科学分野:
- 進化生物学の進化生物学について
- エコロジー エコロジー エコロジー
- 微生物生態学 微生物生態学とは
背景:
- 適応放射線,すなわち系統が異なる種に多様化することは,生物多様性の主要な原動力である.
- 資源の競争は,適応放射線のよく研究された原動力であり,捕食者の役割はあまり理解されていない.
研究 の 目的:
- プロティストの捕食が,細菌の獲物の適応放射線に与える影響を実験的に調査する.
- 多様化の範囲と速度に対する捕食と資源競争の影響を比較する.
主な方法:
- 適応放射線を受けた細菌の獲物 (Pseudomonas fluorescens) のモデルシステムを利用しました.
- 獲物の多様化に与える影響を評価するために,原生肉食動物 (Tetrahymena thermophila) を導入した.
- 捕食者および非捕食者条件下における競合する獲物の推定周波数依存のフィットネス機能.
主要な成果:
- 競争と捕食の両方が独立して多様性の選択を生み出しました.
- 捕食と競争は,多様化を同様の程度に,しかし異なるペースで推進しました.
- 捕食は,獲物の密度が低下したため,多様化の速度を大幅に遅らせました.
結論:
- 捕食は,資源競争に匹敵する,適応放射線における重要な要因である可能性があります.
- 多様化の速度は,特定の生態学的圧力によって影響を受け,捕食が遅延を引き起こします.
- 適応放射線の誘導における捕食者の役割は,進化論の研究で過小評価されているかもしれない.
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