鳥の集団動態の生成時間と時間スケーリング
Bernt-Erik Saether1, Russell Lande, Steinar Engen
1Department of Biology, Norwegian University of Science and Technology, N-7491 Trondheim, Norway. bernt-erik.sather@bio.ntnu.no
Nature
|July 8, 2005
まとめ
集団の動態は密度依存によって影響を受けますが,その強さは種によって大きく異なります. 鳥の世代が長くなることは,より強い密度依存と,より大きな環境変動と相関しています.
科学分野:
- エコロジー エコロジー エコロジー
- 人口生物学 人口生物学
- 進化生物学の進化生物学について
背景:
- 密度依存は人口動態に大きな影響を与えるが,自然集団におけるその強さを制御する要因は依然として十分に理解されていない.
- 密度調節の検出は,生命史の時間遅延のために困難であり,内在的および外在的要因の分離を複雑にします.
研究 の 目的:
- 鳥の生命史の特徴と集団動態の関係を調査する.
- 異なる鳥種の密度依存と環境ストキャスティシティの強さを定量化するために.
主な方法:
- 23種の鳥の個体数のタイムシリーズデータを利用した.
- 主要なパラメータを推定するために,ストキャスティック密度依存年齢構造モデルを使用しました.
主要な成果:
- 密度依存の強さと環境ストキャスティシティの大きさは,生成時間が長くなるとともに増加します.
- また,年齢構造における一時的な変動は,世代とともに増加することが判明した.
結論:
- 鳥の人口統計と生命史の特徴は,異なる集団動態と結びついている.
- これらの人口パターンは,世代間の時間スケールで検討すると明らかになります.
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