created in the laboratory by gluing the tails of rats together; this causes the rats to become so entangled while trying to extricate themselves that a true knot is formed. Yet no zoologist has been able to prove exactly how rat kings are formed in nature. It is possible that the tails become entangled when the rats huddle together facing outward for warmth and security, urine and feces from those in the upper circle falling onto the entwined mass of tails. Other possibilities are that the tails might become entangled while the males are wildly fighting for females, or during mass grooming, or in the nest shortly after birth, or after the tails of a number of rats come into contact with some sticky substance. It may even be that the "verminous vermicelli" are formed in several ways. The rat king remains as much a mystery to nuclear-age scientists as it was to medieval peasants." (2)