An extremely rare two-headed shark found by fishermen off the Brazilian coast is baffling experts.
Researchers believe it is the first ever recorded example of a Siamese twin sandbar shark.
The two-headed specimen was found just off Brazil’s south-eastern coast, in between the municipalities of Itanhaem and Peruibe, by fishermen, who handed it over to a local marine biology institute.
Scientists at the institute examined the Siamese twin sharks, and found they had two hearts and two independent spinal columns.
Biologist Edris Queiroz told local media: “It’s the first case in the world, recorded and documented in literature, of a Siamese twin sandbar shark found in the wild.”
He added: “It’s a very rare event. We must have around 10 cases in the world. The problem is they die quickly, shortly after birth. They become easy prey.”
Edris and his team have been unable to confirm what caused the mutation, but he suggested it could be due to ocean pollution.
He told local media: “Sharks accumulate heavy metals in their food, and this can generate what we call a mutation, an anomaly.”
The biologist also suggested the anomaly may have arisen due to problems in the uterus of the mother.
He said: “Compression of the uterus can cause one egg to merge with another. We cannot be sure because they are extremely rare events.”
Edris hopes that the find will lead to awareness of the serious problems facing marine environments.
Sandbar sharks are native to the Atlantic Ocean and the Indo-Pacific. Their conservation status is classed as ‘vulnerable’.
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Story By: William McGee, Sub-Editor: Joseph Golder, Agency: Newsflash
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