SO LONG, SYMMETRY


Sea Unicorn


A male fi ddler crab has two eyes on long stalks. It crawls sideways on four matching pairs of legs. It’s symmetrical, except for one thing. Check out its huge claw! A fi ddler crab has one big claw and one little claw. The crab waves its big claw to show off. It also uses its big claw to fi ght other male fi ddler crabs.


Crab Claw Flat Fish


Look closely. These three critters are asymmetrical.


When a male narwhal is born, it has two matching teeth in the top of its mouth. The right tooth stays small. The left one grows and grows and grows. It pushes right through the whale’s skin. It can grow up to 3 meters (10 feet) long.


A fl ounder starts life with an eye on each side of its face. Then one eye moves. It slides up and over the top of the fi sh’s head. Now the fl ounder has two eyes on one side of its face. This fl at fi sh often lies on its side on the seafl oor. So it’s a good thing the eye moves. Otherwise, the fi sh would have one eye staring into the sand.


NOVEMBER-DECEMBER 2012 7


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