Biotic interactions can cause allopatry and subsequent speciation: theoretical and empirical approaches

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K14793
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 45040:Ecology and environment-related
• Research Institution: Hokkaido University (2020); Tokyo Metropolitan University (2018-2019)
• Principal Investigator: Yamaguchi Ryo 北海道大学, 先端生命科学研究院, 助教 (80812982)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 種分化 / 種間相互作用 / 地理的隔離 / 数理モデル

Outline of Final Research Achievements

We propose that the geographic isolation of populations can occur not due to physical factors such as tectonic or climatic changes but due to biological interactions represented by hybrid zones. We named this novel process of geographic isolation by interacting closely related species "Biotic Population Subdivision (BPS)." We used natural populations of a species complex of a flightless leaf beetle to test our hypothesis. Using this species complex as an example, we analyzed the repetition of the origination of isolated populations and subsequent speciation in the continuous space using molecular phylogenetic analysis, mating experiments, and mathematical modeling. We showed that interactions in the hybrid zone are one of the factors that drive recurrent speciation.

Free Research Field

進化生態学

Academic Significance and Societal Importance of the Research Achievements

生物の種間相互作用を考慮した地理的隔離のメカニズムを数理モデリングにより解析し、野外と実験下での実証データを得ることで、BPSの枠組みを提唱した。これは従来の古典的な適応放散モデルでは到達できなかった知見であると同時に、非適応的放散の野外での検証例となる。国内外において本課題で提案する新規仮説の提唱・検証は行われておらず、日本独自の生物を用いて研究を展開した点においても、生物多様性の新たな理解に貢献した意義は大きい。