Genetic Structure of the Ryukyu Wild Boar Population on Tokunoshima Island (Japan) Based on Modern and Ancient DNA Analyses: Evidence of Recent Gene Flow from Pigs to Wild Boars

A recent study on Tokunoshima Island, part of the Ryukyu Archipelago, reveals evidence of gene flow from domestic pigs to wild boars (Sus scrofa riukiuanus) through genetic analysis of both modern and ancient DNA samples. The research identified four unique mitochondrial DNA (mtDNA) haplotypes in modern wild boar populations that were also present in archaeological samples dating back over 1000 years, indicating a stable genetic structure over centuries. However, three distinct individuals exhibited genetic signatures inconsistent with the Ryukyu wild boar lineage, suggesting hybridization with domestic pigs. This finding underscores the dynamic genetic interactions between wild and domesticated suids in this UNESCO World Heritage Site.

Takahashi, R., Gushiken, R., Nagata, K., Shinzato, A., Kantha, S. S., & Yasuda, M. (2019). Genetic Structure of the Ryukyu Wild Boar Population on Tokunoshima Island (Japan) Based on Modern and Ancient DNA Analyses: Evidence of Recent Gene Flow from Pigs to Wild Boars. Mammal Study, 44(3), 157. https://doi.org/10.3106/ms2018-0046