The Bonnethead Is the World's First Known Plant-Eating Shark, Researchers Say

Bonnethead shark
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The bonnethead is the first known omnivorous shark.

Move over, Jaws. Eating meat is so last year.

Scientists have learned that the bonnethead shark enjoys supplementing its diet of meat with greens, making it the first known omnivorous shark.

The bonnethead, which is a variety of hammerhead shark, was studied by researchers at University of California Irvine and Florida International University, who discovered that in addition to eating small fish, mollusks and other sea critters, the shark also consumes and digests seagrass.

The bonnethead is common in the waters of the Eastern Pacific and Western Atlantic, as well as the Gulf of Mexico. Researchers had known the shark ate seagrass prior to this study, but what scientists wanted to know was whether the animals actually receive any nutritional value from the consumption of seagrass. 

Turns out the bonnethead actually digests more than half of the seagrass, which is comparable "with young green sea turtles," according to the Guardian. This means the consumption of the seagrass is likely more than just incidental, researchers said.

In addition to turning the concept of the exclusively meat-eating shark on its head, the findings also have implications for the environment, scientists said. 

“If other species are taking omnivorous digestive strategies as well, then we’d need to re-­evaluate their role as top predators," researcher Samantha Leigh told the Guardian.

The findings were published in "Proceedings of the Royal Society B."