OK, not weasel but marten – which is close enough. Asahi Shimbun writes on the identity of a dragon mummy known as a Koryu held in the Shosoin Repository being finally revealed by X-ray photography as belonging to a female marten:
On April 23, the Imperial Household Agency’s Shosoin office based in Nara announced the results of appraisals by zoologists and archaeologists from the National Museum of Nature and Science and the University Museum of the University of Tokyo.
The Koryu is a mummified animal resembling a small dragon that was thought to be a mammal, measuring about 40 centimeters in length from head to part of the tail.
In an investigation in the 1950s, it was tentatively identified as a marten based on the shape of its teeth that can be observed from the outside. Fragments of several other types of mummies have also been handed down as parts of other so-called Koryu.
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When the sixth shogun of the Muromachi Shogunate Ashikaga Yoshinori (1394-1441) visited Todaiji temple in 1429, he cut off a part of Ranjatai agarwood that had been passed down in the repository.
A monk at Todaiji temple wrote in his diary that at the time, the shogun found an object resembling a dragon, which was dried by sunlight. So, the Koryu mummy is believed to exist from around the time.
This time, the mummy of the marten was confirmed by a more comprehensive observation of the teeth and head bones through X-rays.
In addition, radiocarbon dating was used for the first time of a Shosoin Repository treasure, and it was determined that it dates from the mid-11th century to the mid-12th century.
Furthermore, it was found that the fragments from other Koryu kept by the repository included a mole’s front legs, a crow’s legs and a pigeon’s hip bone.
The research group concluded that, considering the records of five repairs to the repository in the 11th and 12th centuries and that there are still gaps in the ceiling of the repository, it is believed that a marten invaded the repository and died and became a mummified animal inside the treasure house.