这是北半球最古老的神秘寺
Cheng-Hsiu Tsai1, James L Goedert2, Robert W Boessenecker3
1Department of Life Science and Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei 10617, Taiwan; Department of Geology, National Museum of Nature and Science, Tsukuba 305-0005, Japan.
Current biology : CB
|March 29, 2024
概括
北半球最古老的有牙的鱼 (Mysticeti),Fucaia humilis,生活在3450万年前. 它的发现表明,鱼生态系统可能在北太平洋与南半球相比,以不同的方式推动了早期的鱼进化.
科学领域:
- 古生物学的古生物学
- 海洋生物学 海洋生物学
- 进化生物学 进化生物学
背景情况:
- 现存的鱼 (Mysticeti) 是没有牙的过动物,但化石证据表明,在晚期欧纪时代,它们的祖先有牙.
- 迄今为止,只有两种埃奥森时代的神秘物,Mystacodon selenensis和Llanocetus denticrenatus,是已知的,它们都来自南半球.
研究的目的:
- 为了描述北半球地质年代学上最早的神秘.
- 调查可能影响了不同半球早期神秘进化的生态因素.
主要方法:
- 一个化石鱼头骨的地质测年 (地质学,生物分层学,磁分层学).
- 化石鱼的年龄与古海洋学事件和化石记录 (如海藻) 的比较.
主要成果:
- 发现了Fucaia humilis sp. 的发现. 诺维亚,北半球最早的神秘,可追溯到最新的伊欧纪 (ca. 34.5 亿年前).
- F. humilis 与太平洋东北部最早的化石海藻同时出现.
- 北太平洋海藻生态系统与小牙神秘动物 (Aetiocetidae) 的辐射之间的假设联系.
结论:
- 发现Fucaia humilis为早期神秘的多样性提供了关键的见解.
- 相反的生态场景 (北方的树林,南方的南极环极流) 可能解释了北半球和南半球神秘的早期进化历史的分歧.
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