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Animals Can Be Born With Two Heads

Animals Can Be Born With Two Heads

You might want to sit down for this one... two-headed sharks are very much a thing. But before you cancel your holiday beach trip for fear of a JAWS-style attack times two, know that the likelihood of a two-headed shark birth is 0.13 percent, and if the shark actually survives, its life will almost surely be brief. Quick—re-book those flights to Florida!

The biological phenomena of animals being born with two heads is called dicephalia. Although rare, two-headed animals have been documented since the 1800s. A producer named Todd Ray actually has the Guinness World Record for the largest collection of two-headed animals, including a two-headed goat and a two-headed albino hog-nosed snake. So what causes this defect—could it be man-made?

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In an October 2016 study on lab-grown two-headed shark embryos, Spanish researchers determined that the sharks' dicephalia was likely caused by a genetic mutation, or "nature's fluke," versus a reaction to chemicals in the lab. Wild sharks, however, are affected by a number of variables. According to National Geographic, scientists postulate that naturally-occurring dicephalia can be caused by "viral infections, metabolic disorders, pollution, or a dwindling gene pool due to overfishing [causing inbreeding]." So keep your beach plans, but maybe watch the news before taking a dip in ocean...

Learn more about dicephalia in nature, as well as other crazy animal facts and mutations in the following videos.

Two-Headed Sharks And Other Crazy Anomalies

Two-headed sharks are definitely a thing! Learn more about dicephalia and other animal anomalies with DNews.

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Animal Facts That Will Make You Feel Weird

Zebras don't have black stripes—they're black with white stripes. BOOM.

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