A strange figure of a shark would surely shock people for it could make them think that what they have seen was a fancy. What caused them to mull over that perhaps it's a trick is that the shark has a distinctive look. Well, the shark just had two heads. This sounded unusual, yet it actually existed. In fact, scientists say more of it were turning up in the whole world.

A fisherman from Florida has heaved a two-headed fetus from a bull shark's uterus, a few years ago. In 2008, in the Indian Ocean, another fisherman has discovered a two-headed blue shark embryo, said the National Geographic.

In 2011, a study elucidated conjoined twins of blue sharks discovered and caught in northwestern Mexico and in the Gulf of California. Among the sharks, blue sharks got the most documented two-headed embryos. Felipe Galvan-Magaña, a study leader from the National Polytechnic Institute of Mexico said that it took the title as the most recorded because this kind of shark, bore so many babies up to 50 at a time.

At present, an embryo of an Atlantic sawtail catshark with two heads have been identified by Spanish researchers. The Journal of Fish Biology stated that in a new study while sharks were raised in the laboratory for human-health research, members of the team had noticed the bizarre embryo in a see-through shark egg.

On November 1, a two-faced calf was the oldest mutation to survive, but the catshark embryo was not the average two-headed animal. It's the first of such of such species from the oviparous shark species which lay eggs.

Few of those eggs were opened for the researchers to study the specimen. Valentin Sans-Coma, the study leader said that its strange look was unperceived whether the animal with deformities would have survived. It was the first of such conjoined twin found in egg-laying sharks. Most likely such lineage don't live that long wherein people could find them.

It has been hard to sought two-headed sharks for they were only minimal and they have been dwelling far between, thus to understand what lies behind its mutation was tough, takepart pointed out.

The study leader, San-Coma and associates claimed that a genetic disorder seemed to be the most reasonable cause for the two-headed catshark. Its embryo were grown in the lab which was approximately 800 specimens. To the best knowledge that they got, it was observed that the eggs were not exposed to any infections, chemicals and radiation.

However, a variety of factors could be the cause of a wild shark's deformations which include viral infections, metabolic disorders, pollution and more. This was perceived as the result of overfishing that led to inbreeding, so genetic abnormalities get apparent.