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The Physics of Fish

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The Physics of Fish

The Physics of Fish

The Physics of Fish

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  • <iframe src="https://www.npr.org/player/embed/1524674/1524675" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">

Fish have developed a neat trick that helps them swim upstream. When water flows past objects in a stream, it develops a string of small whirlpools, or "vortices." A researcher simulated this environment in a tank outfitted with a high-speed camera. They found that fish slalomed in between the vortices and used the energy of each one to help propel them forward — much the same way that a boater uses a sail to tack back and forth in the wind. NPR's Christopher Joyce reports.