Adaptation and evolution of coastal plants into inland habitat on oceanic islands

2015 Fiscal Year Final Research Report

• Project/Area Number: 25840137
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Biodiversity/Systematics
• Research Institution: Museum of Natural and Environmental History, Shizuoka (2015); The University of Tokyo (2013-2014)
• Principal Investigator: Takayama Koji ふじのくに地球環境史ミュージアム, 学芸課, 准教授 (60647478)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 海洋島 / 種子散布 / 遺伝的多様性 / 南太平洋諸島 / 小笠原諸島

Outline of Final Research Achievements

To understand the evolutionary process that coastal plants inhabited inland environments of oceanic islands, which were often observed in many oceanic islands, morphological and phylogenetic analyses were performed in Hibiscus tiliaceus (Malvaceae) in the South Pacific and Bonin (Ogasawara) Islands. Morphological analyses of flowers reviled that the distance between anther and stigma was significantly shorter in inland populations than coastal ones of H. tiliaceus in Marquises Islands. The morphological changes observed in the inland populations should ensure automatic selfing and increase the number of seed sets in poor pollinator fauna in the oceanic islands. Phylogenetic analyses indicated independent origins of H. tiliaceus populations in the Bonin, Tahiti, and Marquises Islands. There were no significant genetic differences between inland and coastal populations of H. tiliaceus in the South Pacific Island, indicating the rapid adaptation into inland habitats.

Free Research Field

植物系統地理学、島嶼生物学