複製された生物的侵入における高度に変動する拡散率:予測可能性の根本的な限界
Brett A Melbourne1, Alan Hastings
1Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309, USA. brett.melbourne@colorado.edu
まとめ
内部要因によって引き起こされる侵入性種の拡散率の変動は高く,単純な環境でも予測不可能です. この研究は,生態学的拡散ダイナミクスにおける内生的な変動性の重要性を強調しています.
科学分野:
- エコロジー エコロジー エコロジー
- 進化生物学の進化生物学について
- 侵襲生物学について
背景:
- 侵襲性種の平均拡散率はよく研究されています.
- 環境または内部要因によって引き起こされる拡散率の変動は,しばしば見過ごされます.
- 固有の変動性 (人口統計学/遺伝的ストキャスティシティ) は,拡散率の変動の重要な,しかし経験的に研究されていない要因である.
研究 の 目的:
- 種の拡散率の変異を誘発する内生的な変動の役割を調査する.
- 侵入ダイナミクスに対する内部ストキャスティシティの影響を実証的にテストする.
- 単純な生態系における侵入の拡散の予測可能性を評価する.
主な方法:
- 粉虫トライボリウムカスタネウム (Tribolium castaneum) の侵入を複製するために実験室のマイクロコスムを使用しました.
- 複数の独立した侵入実験で拡散率を測定し,比較した.
- 外因的および内因的なドライバーを区別するために,拡散率の分散を分析した.
主要な成果:
- 拡散速度の内生的に生成されたバリエーションは,複製侵略の間で著しく高いことが判明しました.
- 観測された変動は,人口統計学的ストキャスティシティーにのみ起因するレベルを超えた.
- 統制された実験室環境でも,固有の予測不可能性が明らかでした.
結論:
- 内生的な変動性は,侵入の拡散率の変動に大きく貢献しています.
- 人口統計のストキャスティシティだけでは,観察された予測不能性を説明することはできません.
- エコロジカル・インヴァージョンの拡散は,単純化された条件下でも,これまで考えられていたよりも根本的に予測が難しい.
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