Nature is a very unpredictable thing. Whenever you seem to think, you have got the better of nature, it will show that why it has managed to come back from whatever natural disaster or manmade calamity, was thrown at it. Humans have been taking advantage of the nature too much and the abuse had reached a stage where nature has begun to fight back. One such phenomenon is seen in the rise in the numbers of two headed sharks found in the world recently and scientists have no idea about the reason.
Fisherman Christian Johnson caught a two headed shark embryo off the coast of Australia in 2008; little did he know that he would start a mystery that hasn’t been solved till today. Again in 2013, a group of fisherman caught a full grown female bull-shark, which had a two headed shark embryo in it. This condition of having two heads in called bicephaly. Blue Sharks have produced most number of two headed embryos because they carry upto 50 babies in the womb.
Recently, scientists hauled in an Atlantic sawtail catshark for research in Spain. It was the first example of this condition in an oviparous shark- shark that lays eggs. However, bicephaly is not beneficial for the sharks.
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Animals with bicephaly or two heads rarely live long. Most of the animals usually die within few hours of birth. In such animals, each head has its own brain and it shares the control of the body parts and limbs. This causes the animals to move in a haphazard condition with both heads vying for control. In snakes, the two heads may even bite each other or try to swallow each other.
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Scientists have been trying to find out the reason behind the rise of numbers of such two headed sharks. They have given reasons such as genetic mutation, pollution and even overfishing to solve this mystery. A scientist Valentín Sans-Coma says” it's unknown whether the deformed animal would have survived. Because it's the first such conjoined twin found in egg-laying sharks, its likely that such offspring don't live long enough for people to find them.”
However they don’t have sufficient data to come to any conclusions as there are still not enough live specimens caught for them to conduct studies on. Marine scientist Dr. Nicolas Ehemann says that,” the two-headed fetuses are more prevalent in nature, then overfishing is a strong culprit as it may cause the gene pool to shrink.”
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