This is scientific American 60 second science.

I'm Christopher Intagiyata.

Sharks aren't typically thought of as vegetarians,

or even omnivores.

But about 10 years ago, scientists documented a dainty relative of the hammerhead shark,

known as a bonnet head shark,

consuming copious amounts of sea grass.

A lot of people kind of just thought that, oh, the sharks were consuming it incidentally

while they're going after crabs and squid and other little invertebrates that live in the

sea grass meadows. Samantha Lee, a PhD candidate at the University of California, Irvine.

So everyone thought they were kind of just passing it through their system

and not really getting anything from it.

So Lee and her colleagues hauled five of the small sharks back to a Florida lab, and they put them on a three-week diet.

90% seagrass, 10% squid.

And they analyzed the digestibility of that diet.

Turns out the sharks actually put on pounds and were

able to digest the sea grass just about as well as young green sea turtles do.

Even though the bonnethead shark has what scientists would deem as a carnivorous gut, they are definitely

acting like omnivores. So there's definitely something going on on probably a

microbial level that's helping them to break down the sea grass.

The full nutrition info is in the proceedings of the Royal Society B.

The study also gives coastal ecosystem managers something new to chew on.

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