A Russian fisherman out on a routine fishing trip on the Northern Dvina River is making headlines across the world, thanks to his unusual catch - a fish with a full set of teeth that eerily resemble ours. 50-year-old Aleks Korbov who revealed his find on September 29th, said that when he first pulled the fish up, he thought it was a common bream, a freshwater fish that is prevalent in the river.
It was only when he unhooked the already dead animal, that he noticed the human-like teeth. Having never seen anything like it, he decided to consult with some friends at the local pub. However, they were not of much help and even a little skeptical of the animal's existence, given Aleks history of telling "tall tales". Fortunately this time around, the fisherman had proof to quell their doubts.
Curious to know what kind of fish it was, Aleks decided to contact the Institute of Fisheries and Oceanography and seek out their expert opinion. Turns out, they had never encountered anything like it either, and had to perform a full autopsy and carry out a series of examinations, before they could solve the mystery.
Their conclusion? It's a Pacu, which believe it or not, is a member the Piranha family. While that may evoke images of dangerous specimans with razor-sharp teeth, Pacus are largely herbivores that live off water plants and algae. Though they will swallow small fish if the opportunity arises, they are not as ferocious as their carnivorous cousins and are therefore, popular with people that like to fill their home aquariums with exotic fish. The reason the locals in Russia had never encountered one, is because Pacus are tropical freshwater fish that are indigenous to South America's Amazon River.
However like this one, they have been occasionally spotted in other parts of the world. Biologists believe that it is not because the fish venture out that far. They think that the displacement is caused by humans who dump the Pacus into non-native environments, once the fish get too big to fit in home aquariums.
Also, Pacus are not the only ones with "human teeth". The sheepshead fish, which is found in abundance along the Atlantic coastline from Cape Cod to the Gulf of Mexico, also share the same trait. Except in their case, they have multiple rows of molars in both the upper and lower jaws. This helps them crack the shells of the crustaceans they feed on.
And of course while we think of it as fish having "human teeth", the reality is that it is humans that have "fish teeth", because as Cornell University evolutionary biologist William Benis succinctly puts it, "Fishes with specialized dentitions long predate the origin of humans."
Resources: uk.news.yahoo.com, mirror.co.uk, csmonitor.com