Scientists haven’t found out yet why there are more two-headed sharks across the world. In other words, if they don’t know what causes this anomaly, they are also unable to develop an effective strategy to prevent it from further occurring.
A team of researchers found last month a two-headed shark embryo in a lab in Malaga. The embryo was from an egg-laying species of shark. Until now, two-headed sharks have been observed just in species which give birth to live baby sharks.
The first specimen was discovered in 2008 in the waters of the Indian Ocean by a fisherman. It is worth mentioning that the mutant baby shark belonged to the blue shark species. Since then, biologists have found several other specimens.
For instance, researchers discovered two-headed sharks from the same species in the NW Mexico as well as in the Gulf of California back in 2011. Two years later, some fishers found caught a bull shark in Florida’s waters.
It turned out the shark was a female pregnant with another two-headed shark. According to Nicolas Ehemann, a marine scientist and shark expert, overfishing has is most likely the leading cause of such anomalies.
He further speculates that the gene pool of the shark has been affected by environmental factors, increasing the risks of various birth defects, including polycephaly, the scientific name of the two-headed sharks’ condition.
Scientists believe that this genetic mutation might also be caused by pollution, metabolic disorders, and viral infections. They also underlined that although fishers and biologists found more two-headed sharks over the past few years, it doesn’t mean that there is a higher number of mutant specimens across the world.
According to some experts, this rising number might represent a solid proof that researchers are more interested in analyzing shark embryos. Air pollution, caused by greenhouse emissions and other factors, has taken its toll on the environment in recent years because it led to climate change and other environmental issues.
Concerning the marine life, the most significant problem is the bleaching event that has decimated 90 percent of the Great Barrier Reef. Scientists will continue their investigation, to find out whether water pollution is related to the appearance of two-headed sharks.
Image Source: Underwa