Roles of interspecific competition on dietary evolution in small mammals

2016 Fiscal Year Final Research Report

• Project/Area Number: 15H06884
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Stratigraphy/Paleontology
• Research Institution: National Museum of Nature and Science, Tokyo
• Principal Investigator: Kimura Yuri 独立行政法人国立科学博物館, 地学研究部, 研究員 (50759446)
• Research Collaborator: ARAI Yoshinori ; CERLING Thure
• Project Period (FY): 2015-08-28 – 2017-03-31
• Keywords: 脊椎動物化石 / 生物地球化学 / 小型哺乳類 / 食性進化 / 古生態学

Outline of Final Research Achievements

Biotic interaction such as interspecific competition for food has been rarely studied and limitedly recognized as a shaping factor for evolutionary patterns, compared to overwhelmingly accumulated evidence on the relationships between abiotic forces and macroevolution. This study aims to examine the role of interspecific competition on isotopic dietary evolution among small mammalian lineages by utilizing a paleontological event that murine rodents completely replaced ‘cricetid’ rodents. Our results indicate that the coexisting time interval can be divided into two subintervals. In the first interval, murine and ‘cricetid’ rodents shifted their isotopic diet oppositely, suggesting that biotic interaction was stronger than environmental filtering. In the second interval, environmental filtering is suggested to be stronger than biotic interaction. These findings show that dietary shift is necessary at the initial timing, not depending on the suggested phylogenetic distances.

Free Research Field

古生物学