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古类分子钟:时间漂移和最近的加速

Soichi Osozawa^1,2, André Nel³

¹Institute of Geology and Paleontology, Faculty of Science Tohoku University Sendai Japan.

Ecology and evolution

|September 20, 2024

概括

这项研究使用贝叶斯推断和化石数据来追溯昆虫的进化,揭示了近期地质时期加速的替代率. 这些发现突出了四季气候变化对昆虫物种和遗传多样性的影响.

科学领域:

进化生物学进化生物学
分子遗传学分子遗传学
昆虫古生物学昆虫古生物学

背景情况:

准确的昆虫进化历史约会对于理解多样化模式至关重要.
以前的分子时钟研究通常依赖于有限的校准点,导致约会不准确.
四季气候波动对昆虫进化的影响仍然是一个活跃的研究领域.

研究的目的:

为主要的昆虫系构建一个强大的,时间校准的系谱树,包括古类,类和新类.
调查将四次期和四次期前校准点纳入对差异时间估计的影响.
在地质时间尺度上分析分子时钟进展和基替代率.

主要方法:

在2685bp序列数据集上使用BEAST v1.10.4的贝叶斯系遗传推理.
纳入22个校准点,包括地质事件 (瑞큐群岛形成) 和多样化的化石数据 (德纪到四季纪).
分析分子时钟的行为和随着时间的推移而发生的基基替代率动态.

主要成果:

产生了322种昆虫种群的日期的贝叶斯推理树,与以前的研究保持一致,但改进了分歧时间.
强大的约会需要包括四年纪和四年纪前的校准点,以减轻过度估计.
基底替代率表现出时间依赖性,从米奥森到现在的指数级增长,可能与四分期气候变化和石灰岩时期可能的峰值有关.

结论:

多种校准策略的整合对于昆虫进化中的精确分子约会至关重要.
季度气候变化可能在昆虫的加速辐射和物种化中发挥了重要作用,特别是古类.
分子时钟的进展是不均的,简单的速率约会方法对于复杂的进化历史是不够的.

关键词:

野兽v1.10.4 的时间在 Odonata 的位置上.大气中的二氧化碳.有碳的碳化物.指数级增加了基准替换率的指数级增加.化石和地质事件校准.冰川时期是冰川时期.四分制四分制是指四分制.tMRCA;四级和前四级校准.

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