"Rat kings are cryptozoological phenomena said to arise when a number of rats become intertwined at their tails, which become stuck together with blood, dirt, and excrement. The animals consequently grow together while joined at the tails, which are often broken. The phenomenon is particularly associated with Germany, where the majority of instances have been reported...Image and text from Wikipedia. Credit to Neatorama.
Most researchers presume the creatures are legendary and that all supposed physical evidence is hoaxed, such as mummified groups of dead rats with their tails tied together. Reports of living specimens remain unsubstantiated…
Specimens of purported rat kings are kept in some museums. The museum Mauritianum in Altenburg (Thuringia) shows the largest well-known mummified "rat king", which was found in 1828 in a miller's fireplace at Buchheim [above]. It consists of 32 rats. Alcohol-preserved rat kings are shown in museums in Hamburg, Hamelin, Göttingen, and Stuttgart. A rat king found in 1930 in New Zealand, displayed in the Otago Museum in Dunedin, was composed of immature Rattus rattus whose tails were entangled by horse hair.
The term rat king has often led to the misconception of a king of rats... The Nutcracker, by Pyotr Ilyich Tchaikovsky, adapts a tale by E. T. A. Hoffmann that features a seven-headed Mouse King as the villain..."
Addendum: Reposted to add this example of a "squirrel king" -
The Animal Clinic of Regina in Saskatchewan, Canada, got a surprise this week when a city worker brought in six squirrels fused together by their tails...
This particular group of six were nesting near a pine tree and sap fused their tails together. A city of Regina worker found the young squirrels and brought them to the clinic. The animals were sedated and the veterinarian team worked to untangle the mess of tails. Their tails were then shaved of the matted fur and they were given antibiotics to prevent infection. (Via Nothing to do with Arbroath)
Addendum: Reposted in order to add this related interesting phenomenon found by my wife at the Buck Manager website:
[T]hese three white-tailed bucks were found locked during the rut. The bucks were located on a ranch in east-central Texas and, from the information that I received, one of the bucks was still alive when the trio was found. Apparently, the antlers were cut from the dead deer and one very tired buck was lucky enough to run back off into the woods.
"...there is nothing worse than finding a dead buck that you did not shoot, but how would you feel if you found not one, but three dead bucks on your property? Okay, it gets worse. What if those three bucks totaled 450 inches of antler? That is exactly what a hunter in the mid-West found on his Ohio farm..."Addendum: And reader Lisa knew of a ancient example of the phenomenon.
"They had the bank of this creek all tore up."