The forests around religious shrines in Japan have historically forbidden hunting and, as a consequence, provide refuge for certain animal species. A well-known example of this is the Japanese sika deer (Cervus nippon), which has historically been considered a holy creature.
Now, a new study says that the sika deer that live around the Japan’s sacred and famous Kasuga Taisha Shrine in the city of Nara, on the main island of Honshu, are genetically unique.
Key points
- A ban on their hunting for almost 1,500 years given their status in Shintoism (Japan’s national religion) has made them a unique species.
- The study has found that the deer living near the shrine and the nearby Todaiji Buddhist Temple in Nara city have unique mitochondrial deoxyribonucleic acid or DNA. MtDNA is only passed from mother to offspring.
- The genomic DNA was extracted and analyzed for two genetic entities: short sequence repeats (SSR), which are inherited from both parents and tend to change frequently during evolution, and mitochondrial DNA (mtDNA), which is only passed down from mother to offspring.
- The deer population was first screened for gene sets in the mtDNA that were inherited together, also known as a haplotype. A haplotype is a group of genes within an organism that was inherited together from a single parent.
- The team found 18 different haplotypes but with a low diversity across populations.
- Using this information, they identified three distinct genetic groups, of which only one had a unique haplotype (S4), indicating a very restricted flow of genes across its maternal lineage.
- Interestingly, this isolated group included the deer around the Kasuga Taisha Shrine. This could be possible as female sika deer tend to migrate less and prefer to remain in their own natal habitat.
(The research is published in the Journal of Mammalogy.)