2013 Fiscal Year Final Research Report
Morphological variability through speciation : A case of a marine planktonic diatom genus Neodenticula
| Project/Area Number |
23540543
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Multi-year Fund |
|---|
| Section | 一般 |
|---|
| Research Field |
Stratigraphy/Paleontology
|
|---|
| Research Institution | Akita University |
|---|
Principal Investigator |
YAMASAKI Chieko (嶋田 智恵子) 秋田大学, 工学(系)研究科(研究院), 研究員 (60597186)
|
|---|
| Co-Investigator(Renkei-kenkyūsha) |
TANIMURA Yoshihiro 国立科学博物館, 地学研究部, 研究G長(退官) (80141985)
TANAKA Yuichiro 産業技術総合研究所, 地質情報研究部門, 主幹 (50357456)
SAITO Megumi 国立科学博物館, 地学研究部, 研究員 (40455423)
YAMASAKI Makoto 秋田大学, 大学院・工学資源学研究科, 准教授 (40344650)
WATANABE Tsuyoshi 北海道大学, 理学部, 講師 (80396283)
|
|---|
| Project Period (FY) |
2011 – 2013
|
| Keywords | 珪藻化石 / 形態 / 第四紀 / 北太平洋 / 古気候 |
|---|
| Research Abstract |
Temporal variability in valvar morphology of a marine planktonic diatom genus Neodenticula was investigated using the Earliest Quaternary sediment cores from the subarctic North Pacific Ocean. Species composition and each species' morphology of the genus changed during the Northern Hemisphere Glaciation, around 2.6 million years ago (Ma).
Drastic morphological change, specifically, a dominance of a "peculiar" type, was recorded just before the extant species appeared in 2.55 Ma based on a biometric measurement of valves. On the other hand, the culture experimental results of the species indicated that the peculiar type appeared when the higher growth rates and lower availability of the major nutrients were brought(Shimada et al., 2009). Thus, we suggest that the moprhological event of the diatom genus in the subarctic Northwestern Pacific Ocean around 2.6 Ma may have reflect a short-term collapse of the nutrient regime in the ocean.
|
