Reports of the bizarre rat king phenomenon date back to the 16th century, but the recent discovery of a Russian farmer who found five small rats with their tails tied in a giant knot is once again causing scientists to scratch their heads.

A rat king occurs when the tails of multiple rodents become so entangled that even an adult human, let alone a creature without opposable thumbs and advanced brain, would have trouble detangling. Rat kings have been reported numerous times since the mid-16th century, but scientists have yet to properly understand how and why it occurs, or even if it is a natural phenomenon or just a man-made hoax. The discovery of a new rat king in a flooded field in Russia has once again brought the very existence of the phenomenon into the debate.

Photo: Alibulat Rasulov

Russian farmer Alibulat Rasulov, who owns agricultural land in the country’s Stavropol region, shared an unusual finding on social media, late last month. In a short clip, he showcases five small field rats  – some alive, some drowned – with their tails tangled in a large knot.

Just like all the other people who have observed the rat king phenomenon over the years, Rasulov was dumbfounded by his discovery but theorized that the rats’ mother somehow secured together in an attempt to keep them from falling into the water that was flooding their home.

The very existence of the rat king phenomenon has been called into question several times, as no example of live rats becoming entangled in this way have been reported in modern times, leading some to believe that it is nothing but a man-made hoax. However, a very similar phenomenon has been observed in other long-tailed rodents, like squirrels, some of which have even been caught on camera. Science has yet to explain how those occur as well.

Several theories to explain the rat king phenomenon have been formulated over the centuries, some completely bonkers, and others are only barely plausible. The most widely accepted theory is that in the case of black field rats, which have very long tails and live together in tight quarters during winter, the tails may come in contact with a sticky or frozen substance (sap, sebum, urine, etc). This causes the tails to become glued together, and the rats then get even more entangled as they try to break free and pull in opposite directions.

Today, the opinion of scientists and historians on the existence of rat king is mixed. Some believe this natural tail entanglement could theoretically occur naturally, while others are convinced that it is just a myth perpetuated by fake examples.

I definitely wouldn’t put it past humans – both in old and modern times – to come up and perpetuate this type of hoax, but at the same time, those modern occurrences involving other rodents hint that there may be some truth to it.