海洋カメのナビゲーションマーカーとしての地域磁場
K J Lohmann1, S D Cain, S A Dodge
1Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA. klohmann@email.unc.edu
Science (New York, N.Y.)
|October 13, 2001
まとめ
若き木頭カメは,地球の磁場をナビゲーションマーカーとして利用しています. これは,北大西洋を横断して北米の海岸に戻る旅のガイドとして,北大西洋を横断して移住するのに役立ちます.
科学分野:
- マリン・バイオロジー マリン・バイオロジー
- 動物ナビゲーション 動物ナビゲーション
- 地質物理学 地質物理学とは地質物理学です.
背景:
- ロガーヘッド海 (Caretta caretta) は,海を越えて広範な移動をします.
- フロリダ州東部の若いカメは,北大西洋の回転を横断して北アメリカに戻る前に,北大西洋の回転を横断して移住します.
研究 の 目的:
- 磁場の役割が若いウミガメの航海に及ぼす影響を調査する.
- カメが異なる海洋地域を模倣する磁場に反応するかどうかを判断するために.
主な方法:
- ヒッチングのロガーヘッドは,3つの異なる海洋の場所からシミュレートされた磁場にさらされました.
- 泳ぐ方向を記録し,それぞれの磁場への反応として分析した.
主要な成果:
- カメは,それぞれの磁場に対して独特の水泳反応を示した.
- これらの反応は,常に北大西洋の渦流の範囲にとどまるようにカメを導いた.
- 磁場は,移動経路に沿ってカメを導くように見えた.
結論:
- 若いロガーヘッドは,ナビゲーションのための磁気感覚を持っています.
- 地域の磁場は,海にとって重要な航海マーカーとして機能します.
- 磁気信号は方向の変化を誘発し,成功する移住を促進します.
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