Scientists confirm first two-headed bull shark

Mar 25, 2013
Scientists confirm first two-headed bull shark. Credit: Patrick Rice, Shark Defense/Florida Keys Community College

(Phys.org) —Scientists have confirmed the discovery of the first-ever, two-headed bull shark.

The study, led by Michigan State University and appearing in the Journal of Fish Biology, confirmed the specimen, found in the April 7, 2011, was a single shark with two heads, rather than conjoined twins.

There have been other species of sharks, such as blue sharks and tope sharks, born with two heads. This is the first record of dicephalia in a , said Michael Wagner, MSU assistant professor of fisheries and wildlife, who confirmed the discovery with colleagues at the Community College.

"This is certainly one of those interesting and rarely detected phenomena," Wagner said. "It's good that we have this documented as part of the world's natural history, but we'd certainly have to find many more before we could draw any conclusions about what caused this."

Credit: Michael Wagner

The difficulty of finding such oddities is due, in part, to creatures with abnormalities dying shortly after birth. In this instance, a fisherman found the two-headed shark when he opened the uterus of an adult shark. The two-headed shark died shortly thereafter and had little, if any, chance to survive in the wild, Wagner added.

"You'll see many more cases of two-headed and snakes," he said. "That's because those organisms are often bred in captivity, and the breeders are more likely to observe the anomalies."

The shark was brought to the marine science department at Florida Keys Community College. From there, it was transported to Michigan State's campus for further examination.

Wagner and his team were able to detail the discovery with . Without damaging the unique specimen, the MRIs revealed two distinct heads, hearts and stomachs with the remainder of the body joining together in back half of the animal to form a single tail.

As part of the published brief, Wagner noted that some may want to attribute the deformed shark to exposure to pollutants.

"Given the timing of the shark's discovery with the Deepwater Horizon oil spill, I could see how some people may want to jump to conclusions," Wagner said. "Making that leap is unwarranted. We simply have no evidence to support that cause or any other."

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User comments : 2

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Kiwini
2.8 / 5 (9) Mar 25, 2013
"First ever"???

How about a far more realistic "first found and photographed" instead.

Sharks have been around a LOT longer than homo saps, and if we've stumbled across this one, it's happened many times before.
Telekinetic
1.6 / 5 (7) Mar 26, 2013
"...but we'd certainly have to find many more before we could draw any conclusions about what caused this."

Try looking off of the coast of Fukushima in a few years.

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