On a cold January morning in 2005, in the village of Saru in southern Estonia, farmer Rein Kıiv and his son made a curious discovery. On the sandy floor of their shed, they found a cluster of 16 rats with their tails inexplicably tangled into a knot. The rats were squeaking and struggling to escape but the harder they pulled the tighter the knot became. The animals were apparently trying to dig themselves out of a narrow burrow but in the struggle some of them got buried under the sand. Seven of the rats in the tangle were already dead. Rein’s son decided to put the diabolic little scene to an end, and picking up a stick, killed the rest of the wretched animals.

Rein Kıiv didn’t know then, but what he had discovered was an extremely rare phenomenon called rat kings. They have been sighted since the past five centuries with approximately 60 such sightings recorded in history books.

Rat king from Dellfeld, Germany, found in 1895. Photo credit: Edelseider/Wikimedia