種子捕食者の予期的な繁殖と人口増加
Stan Boutin1, Lucas A Wauters, Andrew G McAdam
1Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada. stan.boutin@ualberta.ca
Science (New York, N.Y.)
|December 23, 2006
まとめ
リスはマストの播種を予期し,種子パルスより前に繁殖を促進します. これにより,リスの個体数と食糧の利用可能性が同期され,資源パルスシステムにおける普遍的な捕食者の遅滞という考えに異議を唱える.
科学分野:
- エコロジー エコロジー エコロジー
- 動物の行動 動物の行動
- 人口のダイナミクス
背景:
- 大規模な種作物の同期生産であるマスト種植は,生態学的なコミュニティに影響を与える資源パルスを作り出します.
- 捕食動物集団の動態は,遅れた生殖反応のために,これらの資源パルスに遅れていると考えられています.
- この捕食者の遅延は,植物におけるマスト行動の進化を説明する重要な仮説である.
研究 の 目的:
- 種子捕食者,特に木のリスが,迫り来るマストの種まきイベントに反応して,予期的な生殖行動を示すかどうかを調査する.
- 捕食者集団の大きさが資源パルスと同期し,それによって予想される遅延を排除できるかどうかを判断する.
主な方法:
- アメリカとユーラシアの樹木リスの集団の監視.
- 既知のマスト種まきサイクルに関連した生殖生産量の観察.
- 種子の利用可能性と同期した集団動態の分析.
主要な成果:
- アメリカンとユーラシアのツリーリスは,マストシードイベントの前に生殖能力が増加したことを示しました.
- リスの集団の大きさは,種資源パルスと同期して増加した.
- この研究では,リスの予期的な行動を特定し,予測された人口遅延を否定しました.
結論:
- リスのような種を食う肉食動物は,資源パルスに対する予期的な反応を示し,確立された生態学理論に異議を唱えます.
- 捕食者の遅延の排除は,マストシステムにおけるより複雑な捕食者-獲物のダイナミクスを示唆しています.
- リスの予想行動は,植物マスタリングの進化と生態学的影響の決定的な要因かもしれません.
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