Evolutionary history of Japan Sea element plants: a comparative phylogeographic approach using genome-wide SNPs

2023 Fiscal Year Final Research Report

• Project/Area Number: 18K06394
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 45030:Biodiversity and systematics-related
• Research Institution: Ochanomizu University (2021-2023); Kanagawa University (2018-2020)
• Principal Investigator: Iwasaki Takaya お茶の水女子大学, 基幹研究院, 講師 (10636179)
• Project Period (FY): 2018-04-01 – 2024-03-31
• Keywords: 日本海要素 / 地域固有種 / 種分化 / 多雪 / 分子系統地理 / ゲノムワイドSNPs

Outline of Final Research Achievements

The objective of this study was to elucidate the evolutionary history of the Japan Sea Elements, groups of plants endemic to the Sea of Japan region, characterized by heavy snowfall. We estimated the history of population differentiation based on genome-wide SNPs and changes in distributional ranges, using ecological niche modeling for two species groups. The results showed that despite significantly different divergence times, with Viola diverging in the early Quaternary and Hepatica during the last glacial period, the Japan Sea Elements lineage and a related lineage on the Pacific side have differentiated most recently within each species group. Combined with the results of ecological niche modeling, it appears that the Japan Sea Elements differentiated from their closely related Pacific counterparts, with niche differentiation likely triggered by distributional fragmentation during a glacial period after the Japan Sea climate became dominant in the Quaternary.

Free Research Field

分子系統地理学

Academic Significance and Societal Importance of the Research Achievements

日本列島の狭い地理的範囲の中で積雪量が劇的に変化する日本海側気候は他地域ではほとんどみられない独特なものであり、その環境に適応して進化した可能性がある固有種群の集まりである日本海要素の進化史の解明は日本列島における生物多様性の形成過程を明らかにする上で大きな意義がある。本研究成果からは、第四紀で日本海側気候が卓越するようになった後に、太平洋側に分布する近縁な系統から日本海要素の系統がニッチ分化を伴って分化したことが示唆され、これは日本列島における第四紀種分化プロセスの一つの重要な例になると思われる。