陆地植物起源于藻的化石记录
Paul K Strother1, Clinton Foster2
1Weston Observatory, Department of Earth and Environmental Sciences, Boston College, Weston, MA 02493, USA. strother@bc.edu.
概括
早期奥尔多维纪 (480万年) 的化石植物子弥合了藻类祖先和胚胎之间的进化差距. 这一发现表明陆地植物的进化历史比以前记录的更长,更连续.
科学领域:
- 古植物学
- 进化生物学
- 分子遗传学
背景情况:
- 分子时钟数据表明胚胎 (陆地植物) 起源于5亿年前的坎布里亚时期.
- 然而,陆地植物的化石记录显示,它们的首次出现是在西鲁纪中期 (大约430万年前),造成了显著的时间差异.
- 这种差距在很大程度上归因于缺失的化石记录,
研究的目的:
- 研究胚胎生物及其藻类祖先的早期进化历史.
- 解决分子分离时间和陆地植物化石记录之间的差异.
- 通过化石子提供进化连续性的证据.
主要方法:
- 来自特雷马多纪 (奥尔多维纪早期,约480万年前) 的化石子组合的描述和分析.
- 化石子组合与坎布里亚和较年轻的胚胎子进行比较.
- 化石证据与分子遗传数据的整合.
主要成果:
- 发现了早期奥尔多维纪 (大约480万年前) 的子组合,其中包含了坎布里亚和较年轻的胚胎子的特征.
- 这种组合表明了早期陆地植物和它们的藻类祖先之间的进化连续性.
- 这些发现表明,胚胎发育基因组的获取比以前想象的更早,可能是在埃迪亚卡-坎布里亚.
结论:
- 早期奥尔多维纪的子化石记录为胚胎生物的早期进化提供了关键证据.
- 分子遗传信号可能反映出发育基因组的潜在进化历史.
- 胚胎发育基因组的完整获取可能是逐渐发生的,在西鲁纪中期达到顶峰.
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