An unsuspecting fisherman recently stumbled across an incredibly rare two-headed dolphin. Only nine examples of conjoined twins have ever been found among cetaceans, according to Erwin Kompanje, curator of mammals for the Natural History Museum Rotterdam in the Netherlands. So he jumped at the chance to study a rare specimen of conjoined harbor porpoises caught the end of May by Dutch fisherman. But when he reached out to the fisherman, what happened next was a scientist’s nightmare.
It’s not unheard of for trawlers to accidentally catch a porpoise. There are hundreds of thousands of the cetaceans near the coast of the Netherlands. But no one has ever caught conjoined twin harbor porpoises. The fisherman snapped photos, which made their way to Kompanje. He couldn’t wait to study the creature in the laboratory.
Kompanje could tell the twins were male, and had likely recently been born – and he thinks they were born alive. They probably didn’t live for long; either they had two brains which might have told them to swim in different directions, or a single heart may have failed to pump enough blood to keep them alive.
Conjoined twins are an extremely rare find. And these looked to be in good condition. Others that have been discovered were undeveloped fetuses – such as one found near Japan in 1970 in a dolphin’s womb – or have started to decompose, such as a dolphin with two beaks found in 2001. Kompanje reached out to the fisherman to try and obtain the specimen for study.
But this story doesn’t have a happy ending for science. The fisherman thought it was illegal to catch the conjoined twins, so after the photographs, they tossed the creature back into the sea. Kompanje told The Washington Post, “For a cetologist, this is a real horror.”
Based on the photographs he was still able to publish a paper in DEINSEA, the online journal of the natural history museum, joined by one scientist of the Royal Netherlands Institute for Sea Research and one from Wageningen Marine Research. Sadly, we may never know more about the rare twins.