How 3D Changes in the Genome Turned Sharks Into Skates

The marine creatures called skates skim along the sea bottom, rippling their winglike pectoral fins to propel themselves and to stir up small creatures hiding in the sand. Their unusual flattened body plan makes them one of the oddest families of fish in the sea, and it seems even odder that they evolved from streamlined, sharklike carnivores that swam about 285 million years ago.

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