競争,植民地化,絶滅が歯類の種多様性に及ぼす影響

T J Valone¹, J H Brown

¹Department of Biology, University of New Mexico, Albuquerque 87131.

Science (New York, N.Y.)

|February 10, 1995

まとめ

カンガルーラットの除去により,チワフアン砂漠の種多様性が増加した. これは,小型のネズミがより簡単に植民し,カンガルーラットとの競争なしに長生きできるからです.

科学分野:

エコロジーエコロジーエコロジー
コミュニティエコロジーコミュニティエコロジー
エコシステムのダイナミクス

背景:

カンガルーラット (Dipodomys spp.) チワフアン砂漠の生態系における支配的な競争相手である.
ネズミのコミュニティ構造は,異種間の競争と空間的ダイナミクスの影響を受けます.
種の多様性に影響を与える要因を理解することは,保全のために極めて重要です.

研究の目的:

カンガルーラットの影響が他のネズミの種多様性に及ぼす影響を調査する.
生物多様性の維持における競争的排斥とメタポピュレーションのダイナミクスの役割を決定する.

主な方法:

チワフアン砂漠の長期実験データの分析.
カンガルーラットとカンガルーラットのないプロットにおける歯類の種の多様性の比較.
小粒を食べるネズミのコロニー化と絶滅の可能性の評価.

主要な成果:

他のネズミの種多様性は,カンガルーラットが除去されたプロットでは著しく高かった.
カンガルーラットの不在は,小粒を食べるネズミのコロニー化が増加し,絶滅の可能性が低下した.
カンガルーラットは,コミュニティの構造に強い競争力を発揮します.

結論:

カンガルーネズミによる競争的排除は,他の歯類の多様性を大幅に減少させます.
競争の影響を受けるメタポピュレーションのダイナミクスは,生物多様性の規制において重要な役割を果たします.
生態系実験は,生態系のコミュニティの構造化において支配的な種の重要性を強調しています.

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