最早的血管陆地植物的起源和辐射
Philippe Steemans1, Alain Le Hérissé, John Melvin
1Palaeobotany, B-18, University of Liège, 4000 Liège, Belgium.
Science (New York, N.Y.)
|April 18, 2009
概括
早期的陆地植物,如植物,在数百万年内占据主导地位. 新的化石证据表明,血管植物的起源和多样化早于人们所认为的在冈德瓦纳.
科学领域:
- 古植物学是古植物学.
- 进化生物学 进化生物学
- 地质历史地质历史
背景情况:
- 植物对土地的殖民化始于中奥尔多维纪中期,具有类似于植物的世界性植物群.
- 这种早期的植物群,以密度和植物碎片为代表,持续了大约3000万年.
- 显著的转变发生在早期的鲁纪,密码体的减少和多样化的三角体子的增加,与血管植物巨石化石相吻合.
研究的目的:
- 调查血管植物多样化的时间和起源.
- 根据新的化石发现,重新评估关于早期血管植物进化的先前假设.
主要方法:
- 对化石化分散的密码体和碎片植物遗骸的分析.
- 从晚期奥尔多维纪沉积物中识别和描述三体子.
- 子组合与现有的化石记录和地质时间表的比较.
主要成果:
- 在奥尔多维纪晚期发现了多种多样的三叶虫子.
- 这一发现表明,血管植物的起源和多样化比以前假设的更早.
- 数据表明起源于冈德瓦纳,随后是迁移和二次多样化.
结论:
- 血管植物很可能起源于冈德瓦纳,并在奥尔多维纪晚期在冈德瓦纳多样化.
- 三叶虫子的出现和多样化标志着一个关键的进化过渡.
- 这一修订的时间表影响了我们对早期陆地生态系统和植物进化的理解.
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