The Mystery of Tsushima Island: What's Wrong with the Leopard Cats

On the Japanese island of Tsushima, rare leopard cats have been found with an anomaly—tails half the normal length. Scientists tested the hybridization hypothesis with domestic cats, but genetic analysis did not confirm crossbreeding. The cause of the anomaly remains unclear; inbreeding and congenital pathologies are being considered.

On the isolated Japanese island of Tsushima, scientists have recorded an anomaly among local leopard cats: several individuals have tails roughly half the normal length. The population of the Tsushima leopard cat (Prionailurus bengalensis euptilurus) numbers about a hundred individuals and is endangered. Researchers hypothesized that the short tail is a result of hybridization with domestic cats, which also live on the island. Japanese scientists sequenced the complete genome of a captured short-tailed cat and compared it with the DNA of local domestic cats and other wild individuals. The results showed no signs of recent crossbreeding. Geneticist Yuki Matsumoto explained that the external resemblance to hybrids was not confirmed. Other versions are being considered: inbreeding (but its level in this individual did not exceed the population average) and congenital developmental pathologies. The anomaly has been confirmed in only one individual, with two more recorded by camera traps. Biologists urge caution in drawing conclusions.