沈むか泳ぐか:海洋哺乳類による費用対効果の高いダイビングのための戦略
T M Williams1, R W Davis, L A Fuiman
1Department of Biology, EMS-A316, University of California, Santa Cruz, CA 95064, USA. williams@darwin.ucsc.edu
まとめ
海の哺乳類は,潜水中に滑翔でエネルギーを節約し,エネルギーコストを最大59.6%削減する戦略です. これにより,息を止める時間が長くなり,より深い潜水が可能になり,ダイビング能力が向上します.
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
- バイオメカニクス バイオメカニクス
背景:
- ダイビングする海洋哺乳類は,移動中に予想される有酸素能力をしばしば超えています.
- ダイビング中の息を止めるには,効率的なエネルギー使用が必要です.
研究 の 目的:
- ダイビング中のエネルギー効率を改善するために,海洋哺乳類が採用する行動戦略を調査する.
- これらの戦略がエネルギー支出とダイビングパフォーマンスに与える影響を定量化する.
主な方法:
- 潜水カメラを使って,自由にダイビングしているシールやクジラの映像を撮影した.
- 運動パターンとダイビングプロフィールを分析し,降下期間と深さに焦点を当てました.
主要な成果:
- 長い滑り (下降の78%以上) は,80メートル以上の深さでのダイビングで観察されました.
- 滑翔は,肺圧縮による浮力変化と関連していた.
- ウェッデル海は,変化した運動パターンを用いて潜水時のエネルギーコストを9.2%から59.6%削減することが示された.
結論:
- 海の哺乳類は,深い潜水中に滑翔をエネルギー節約戦略として採用しています.
- この戦略は,代謝需要を減らすために物理的原理 (浮力変化) を活用します.
- 滑翔によるエネルギー節約により,エアロビックダイビングの期間が長くなり,酸素が限られている状況下でもより深い深さまで到達できます.
関連する概念動画
Tonicity in Animals
The tonicity of a solution determines if a cell gains or loses water in that solution. The tonicity depends on the permeability of the cell membrane for different solutes and the concentration of nonpenetrating solutes in the solution within and outside of the cell. If a semipermeable membrane hinders the passage of some solutes but allows water to follow its concentration gradient, water moves from the side with low osmolarity (i.e., less solute) to the side with higher osmolarity (i.e.,...
Osmoregulation in Fishes
When cells are placed in a hypotonic (low-salt) fluid, they can swell and burst. Meanwhile, cells in a hypertonic solution—with a higher salt concentration—can shrivel and die. How do fish cells avoid these gruesome fates in hypotonic freshwater or hypertonic seawater environments?
Comparative Excretory Systems
Animals have evolved different strategies for excretion, the removal of waste from the body. Most waste must be dissolved in water to be excreted, so an animal’s excretory strategy directly affects its water balance.
Buoyancy
When an object is placed in a fluid, it either floats or sinks. All objects in a fluid experience a buoyant force. For example, a metal ball sinks, while a rubber ball floats. Similarly, a submarine can sink and float by adjusting its buoyancy. The concept of buoyancy raises several interesting questions. For instance, where does this buoyant force come from? How much buoyant force is required to make an object sink or float? Do objects that sink get any support at all from the fluid?
To get...
To get...
Buoyancy and Stability for Submerged and Floating Bodies
In fluid mechanics, buoyancy and stability are key concepts for understanding the behavior of submerged and floating bodies. When a stationary body is fully or partially submerged in a fluid, the fluid exerts a force on the body known as the buoyant force. This force acts vertically upward through a point called the center of buoyancy, which is the center of the displaced fluid volume. According to Archimedes' principle, the magnitude of the buoyant force is equal to the weight of the fluid...
Deep Sea Microbial Ecology
The deep ocean and its underlying sediments represent vast, largely unexplored microbial habitats that extend far beyond the sunlit photic zone. The photic (euphotic) zone typically spans the upper ~100–200 meters of pelagic waters in the open ocean, but its depth varies geographically and seasonally, where sufficient light supports photosynthetic life. Below this lies the deep sea, spanning roughly 1000–6000 meters (bathypelagic to abyssal zones), with deeper hadal trenches extending beyond...


