Understanding the significance of biotic factors in long-term evolution based on the fossil records of micromammals

2022 Fiscal Year Final Research Report

• Project/Area Number: 18K13650
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 17050:Biogeosciences-related
• 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, 研究主幹 (50759446)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Keywords: 進化古生態学 / 同位体生態学 / 脊椎動物化石 / 化石哺乳類

Outline of Final Research Achievements

This study aims to reveal the significance of biotic factors in long-term evolution by monitoring dietary and morphological evolution based on fossil lineages of micromammals that experienced inter-lineage competition and introduced species in an insular system. A feeding-controlled experiment was conducted to refine an isotopic enrichment factor between diet and bioapatite, which was applied to other studies in this project. We showed that a rodent lineage that acquired dental traits more advantageous to tough diets exploited more C4 grasses through time compared to the other coexisting lineage. We recognized two new species in these evolving lineages. In the study of extirpated bat populations on an oceanic island, we evidenced that the extirpation event was caused by human activities including sugarcane plantation.

Free Research Field

古生物学

Academic Significance and Societal Importance of the Research Achievements

地域の生物多様性は，生態系の生物群集が互いに複雑につながりあった食物連鎖のネットワークに，生物種の進化の歴史と地球環境の変動が組み込まれることで成り立っている．近年，生物多様性の未来予測をする上で，絶滅種の挙動がモデルの制約条件などに役立つとして注目され始めている．本研究の結果は保全古生物という新しい枠組みで生物多様性の理解を促進するものである．