Yeah, my body was definitel not designed to move this way.

Why do crabs walk sideways?

Once upon a time, crabs moved in a forward motion like lobsters, or like you and me for that matter.

But scientists say about 200 million years ago, crabs evolved to move side to side.

Once they found this unique, cool, new way of moving, they never looked back.

Sideways walking has come with massive benefits to these crabby little creatures.

It makes them quicker, which is important when your life depends on outrunning a predator, and the sideways motion also makes their movement less predictable to predators, which gives crabs an even bigger advantage.

Although most crabs move sideways, they are also able to shuffle a little bit in a forward motion.

They're just not as quick moving that way.

Crabs have joints that hinge like our knees and elbows do, but they bend sideways instead of forward and back.

And some crabs, like hermit crabs, actually do still move forward and backward instead of side to side.

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