但时钟,点击点击:一个实证案例研究强调了放松的时钟模型在总证据约会中的优势
Nicolás Mongiardino Koch1,2,3, Jeffrey R Thompson4,5, Rich Mooi6
1Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USA.
Systematic biology
|August 12, 2025
概括
选择正确的遗传时钟模型对于精确的鱼进化时间估计至关重要. 不同的放松时钟模型显著影响树木拓,分歧时间和宏观进化见解.
科学领域:
- 进化生物学 进化生物学
- 人类遗传学 是一个学科.
- 古生物学的古生物学
背景情况:
- 遗传学时钟模型通过将进化变化转化为过期时间来估计进化时间.
- 放松时钟模型解释了整个家族遗传树分支的速率变化,是贝叶斯约会的关键.
- 放松时钟模型对总证据类遗传学的影响,特别是当整合不同的数据集时,需要进一步调查.
研究的目的:
- 探索不同放松时钟模型 (自相关与非相关) 对类动物总证据遗传学的后果.
- 研究树木拓,时钟模型和化石种群作为直接祖先的位置之间的相互作用.
- 评估放松时钟模型选择对差异时间估计和下游宏观进化推断的影响.
主要方法:
- 综合了主要鱼系的形态学,转录学,桑格测序和层级学数据.
- 进行了总证据日期推断,使用之前的化石出生死亡.
- 通过比较自身相关和非相关的放松时钟,以及评估化石直接祖先的恢复,多样化分析条件.
主要成果:
- 观察到树和时钟模型之间的相互作用;自相关时钟分析未能恢复直接的化石祖先.
- 放松时钟模型的选择显著影响了树木拓,化石放置,分歧时间和宏观进化推断.
- 化石数据对快速演变的分子区域的分歧时间的影响很小,化石的位置受到分子数据年龄的影响.
结论:
- 来自总证据约会的遗传学和宏观进化结论高度依赖于选择的放松时钟模型.
- 在选择放松时钟模型用于植物遗传学分析时,方法验证或灵敏度评估至关重要.
- 建立了基于遗传学分析的Apatopygoida序列,化石的放置严重依赖于分子数据建模.
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