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.
