解构 angiosperms 的年龄估计
Tom Carruthers1, Robert W Scotland2
1Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA.
Molecular phylogenetics and evolution
|June 17, 2023
概括
使用分子谱系来估计芽细胞的年龄是复杂的. 这项研究用更少的假设重新估计了血管精子年龄,产生了广泛的范围 (130-400万年),但精度降低,突出了假设严格性的影响.
科学领域:
- 进化生物学是进化的生物学.
- 古植物学是古植物学.
- 分子遗传学分子遗传学
背景情况:
- 估计从分子基因学来估计苗 (开花植物) 的进化时间表是具有挑战性的,因为结果是可变的.
- 现有的方法依赖于关于分子进化速率 (时钟模型) 和家族遗传分支持续时间 (化石校准,分支过程) 的假设.
- 证明这些假设的准确性与分子进化和化石记录的当前知识相比往往很困难.
研究的目的:
- 为了重新估计血管苗的年龄.
- 尽量减少年龄估计中的假设,从而避免其他方法固有的局限性.
- 评估假设严格性对年龄估计精度的影响以及分子数据集的影响.
主要方法:
- 使用一组最小的假设重新估计血管精子年龄.
- 分析了四个不同的分子数据集.
- 根据对进化速率和时间持续时间的不那么严格的假设,对年龄估计进行比较.
主要成果:
- 在分析的四个数据集中,血管苗的年龄估计是一致的,从1.3亿年前到4.0亿年前 (Ma).
- 与以前的研究相比,这些年龄估计的准确性明显较低.
- 精度的降低直接归因于对进化速率和时间的不那么严格的假设的使用.
- 分析的特定分子数据集对结果的年龄估计的影响最小.
结论:
- 用最小的假设重新估计血管精子年龄,可以提供广泛但不那么精确的时间表.
- 关于进化速率和时间的假设的严格性显著影响了家族遗传年龄估计的准确性.
- 当假设放松时,分子数据集的选择对血管精子年龄估计的影响有限.
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