餌を食うグレークジラの口の中での温度調節
1Section of Vertebrates, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA. heyning@bcf.usc.edu
まとめ
グレークジラ (Eschrichtius robustus) は,その巨大な舌に特化した血管ネットワークを持っています. これらの逆流熱交換器は,冷たい水中の熱損失を最小限に抑え,餌の時の熱調節を助けます.
科学分野:
- マリン・バイオロジー マリン・バイオロジー
- 動物生理学 動物生理学
- 温度調節 温度調節 温度調節 温度調節
背景:
- グレークジラ (Eschrichtius robustus) のような海洋哺乳類は,寒い環境に住み,効率的な温度調節を必要とします.
- 舌は大きく,血管が豊富にある器官で,動物の全体的な熱交換に役割を果たします.
- 熱の保存メカニズムを理解することは,冷たい水域での海洋メガファウナの生存に不可欠です.
研究 の 目的:
- 灰色クジラの舌の中の血管構造を調査し,熱の保存に責任があります.
- 体の他の部分と比較して,熱調節における舌の血管化の役割を定量化するために.
- 寒い海で餌を食べるグレークジラに対するこれらの適応の機能的意義を明らかにする.
主な方法:
- グレークジラの舌の血管構造の解剖学的検査.
- 逆流熱交換器システムの識別と特徴付け.
- 生きたグレークジラの口腔内におけるin-situ温度測定.
主要な成果:
- 灰色のクジラの舌全体で,多数の個別の対流熱交換器が特定されました.
- これらの血管ネットワークは,舌の根元で二極の retia のペアに収束します.
- 温度データによると,舌の高血管化と低絶熱性にもかかわらず,舌よりも脂肪の層を通して熱の損失が大きいことが示唆されています.
結論:
- グレークジラの舌は,熱損失を大幅に減らすための洗練された対流熱交換器を装備しています.
- これらの血管の適応は,寒い海洋環境で飼育する際に体温を維持するために重要です.
- 熱調節における舌の役割は,冷水での生存のための他の生理学的および形態学的適応を補完する実質的なものです.
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Gently slide the probe cover until a click is heard. This simple action prevents cross-contamination and ensures the correct placement of the probe cover.
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