精子细胞分子钟:时间漂移和最近的加速
1Institute of Geology and Paleontology Faculty of Science, Tohoku University Sendai Japan.
Plant-environment interactions (Hoboken, N.J.)
|September 22, 2025
概括
开花植物的进化显示了两个主要的辐射事件:白纪中期的扩张和阿萨鲁姆和维奥拉等物种的四季度适应辐射. 环境变化很可能推动了这些进化突发.
科学领域:
- 进化生物学 进化生物学
- 古植物学是古植物学.
- 人类遗传学 是一个学科.
背景情况:
- 苗 (开花植物) 的进化通常可以追溯到白纪中期.
- 最近的适应性辐射,如阿萨鲁姆和维奥拉的辐射,发生在四年纪.
- 了解植物进化需要准确的分子计时仪.
研究的目的:
- 为精子植物 (种子植物) 构建一个强大的,精确校准的时间树.
- 为了研究血管精子进化辐射的时间和驱动因素.
- 为了使分子时钟的估计与地质和环境事件相协调.
主要方法:
- 使用安吉奥精子生殖组 (APG) 系统进行遗传学分析.
- 用贝叶斯进化分析采样树 (BEAST) v1.10.4进行分子约会,具有替代约会功能.
- 对地质时间的基底替代率的分析.
主要成果:
- 一个精确校准的Spermatophyta时间树被构建,节点日期与最近的大树不同.
- 在最近的地质时代中,发现了基替代率的指数级增长,之前是白纪中期的增长.
- 这些速率的增加与物种 (四世) 和秩序 (白纪中期) 层面的血管精子辐射相关.
结论:
- 植物进化,包括芽种辐射,受到环境因素的影响.
- 季度辐射可能与C4草的增殖,大气二氧化碳的减少和冰川周期有关.
- 纪中期的辐射可能涉及与草食甲虫的共同进化.
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