A shark’s birthday suit not only fits perfectly, but is very fashion forward. Tiny teethlike ridges covering sharks’ skin appear to give the fish a push forward in water, a new study finds.
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These ridges, or denticles, increase swimming speed and appeared to improve thrust, Harvard University researchers report in the March 1 Journal of Experimental Biology. Meanwhile, similar work with samples of Speedo fabric, designed to look like sharkskin, did not show a consistent improvement in swimming performance.
Much like how a golf ball is able to smoothly soar through the air because the dimpled surface distorts the surrounding airflow, the tiny teethlike structures found on some types of sharkskin are widely believed to reduce resistance in water. Until now, scientists weren’t aware of the added benefits these ridges provided.