Rare Two-headed Porpoise Found by Fishermen off the Coast of the Netherlands

A two-headed porpoise has been discovered off the coast of the Netherlands. The discovery was made by a group of fishermen last month when they were going through their daily fishing routine. These fishermen noticed a baby porpoise stuck in one of the nets. The fishermen took photographs of the rare creature, and then threw it back into the ocean.

This is the first instance of such a specimen being found. It features two fully-grown head in a single body. According to scientists, this is a case of partial twinning, and the 10^th reported case of conjoined twins in cateceans.

According to researchers, partial twinning happens when (1) two initially separate embryonic discs fuse together, or (2) when the zygote partially splits during the early development process.

“The anatomy of cetaceans is strikingly different from terrestrial mammals with adaptations for living in the sea as a mammal. Much is unknown,” said Erwin Kompanje at the Erasmus MC University Medical Center in Rotterdam in the Netherlands.

“Adding any extra case to the known nine specimens brings more knowledge on this aspect,” said Kompanje who is one of the authors of the paper describing the discovery.

Kompanje was disappointed to know that the specimen had been thrown back into the sea.

“For a cetologist, this is a real horror,” he said, according to Miami Herald.

“Normal twins are extremely rare in cetaceans,” noted Kompanje, according to New Scientist. “There is simply not enough room in the body of the female to give room to more than one fetus.”

Researchers believe the specimen were most likely dead when caught. They probably died shortly after birth. Researchers noticed that their tail had not stiffened, which was necessary for them to swim. They had a flat dorsal fin as well as hairs on the upper lip.

Harbor porpoises are the most commonly found cetaceans in the waters of northwest Europe, according to a recent study.

Fishermen threw the specimen back to the ocean as they thought it would be illegal to keep such an animal.