As if sharks - as awesome as they may be - could be more of a hypothetical swimming threat, there are now two-headed ones knocking about.
National Geographic has clocked on to the growing appearance and discovery of these apparent wonders.
Image: Christopher Johnston/ National Geographic
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They wrote: "A 2011 study described conjoined twins discovered in blue sharks caught in the Gulf of California and northwestern Mexico. Blue sharks have produced the most recorded two-headed embryos because they carry so many babies-up to 50 at at time."
Other discoveries include one found off the coast of Florida and another in the Indian Ocean.
Spanish scientists revealed they too have witnessed one of their lab shark embyros growing two heads.
Image: Dr. Michael Wagner
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"Each head had a mouth, two eyes, a brain, a notochord [like a spinal cord], and five gill openings on each side," they said in a study.
While it's unknown as to what the direct cause of these mutations is, previous cases have been linked to infections, pollution and John Carpenter scripts.
Featured image credit: Christopher Johnston/National Geographic
Featured Image Credit:Topics: shark