Why Some Seashells Spiral Clockwise While Others Turn Counterclockwise
为何某些贝壳顺时针螺旋而另一些逆时针旋转
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Most seashells coil in a right-handed (clockwise) spiral due to dominant genetic instructions encoded in snail DNA.
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A rare mutation in the formin gene can flip shell asymmetry, causing left-handed coiling in otherwise identical species.
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