寄生虫の規制的役割:宿主集団への影響は,資源の利用可能性に合わせて変化する
J O Washburn1, D R Mercer, J R Anderson
1Department of Entomology, University of California, Berkeley 94720.
Science (New York, N.Y.)
|July 12, 1991
まとめ
Lambornella clarkiによる寄生虫感染は,食糧が豊富だったときに蚊の個体数を減少させた. しかし,食糧不足の状況では,これらの感染症は競争を減らすことによって蚊に恩恵を与え,より高いフィットネスを有する成人を増加させました.
科学分野:
- エコロジー エコロジー エコロジー
- 寄生虫学とは,寄生虫学である.
- エントモロジー エントモロジー学
背景:
- 寄生虫感染症は,宿主集団に大きな影響を及ぼします.
- ランボルネラ・クラークキ (Lambornella clarki) は,蚊のアエデス・サーレンシス (Aedes sierrensis) のシリアート寄生虫である.
- 幼虫の宿主-寄生虫のダイナミクスは,食糧の利用可能性などの環境要因の影響を受けます.
研究 の 目的:
- Aedes sierrensisの幼虫集団に Lambornella clarkiの感染が及ぼす影響を調査する.
- 食糧の利用が宿主-寄生虫の相互作用と結果をどのように調節するかを決定する.
主な方法:
- 実験室とフィールドでの研究が行われました.
- Aedes sierrensisの幼虫集団は,さまざまな食物条件下で監視されました.
- 寄生虫の発生率と蚊の出現を定量化しました.
主要な成果:
- 食料が充足した条件では,Lambornella clarkiの感染が追加的な死亡率を引き起こし,新興の成虫蚊を減少させた.
- 食物制限条件下では,感染は補償的または補償的死亡率をもたらし,対照群と比較して,成人数がより多くまたは同等であった.
- 食糧不足の下での寄生は,幼虫の競争を緩和し,一人当たりの食糧資源を増やし,成人の平均体格を改善しました.
結論:
- 食品の利用可能性は,Lambornella clarkiがAedes sierrensisに与える影響を媒介する重要な要因です.
- 寄生虫は,資源レベルによって宿主集団の動態に対照的な影響を及ぼします.
- 資源の制限下では,寄生虫感染症は,競争を緩和することによって,宿主の体格を逆説的に高めることができます.
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