Crustacean shuffle
By Amy Maxmen
A modified joint might have made all the difference to scurrying crabs as they diverged from their plodding lobsterlike brethren.
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Comparing leg shape, size, and motion among three living crustaceans from increasingly ancient origins allowed Andrés Vidal-Gadea, at Louisiana State University in Baton Rouge, and his colleagues to get at the mechanics of crab walking: specifically, how some crustaceans changed their forward march into a sideways scuttle.