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哺乳动物进化的物种级时间表,整合了基因组数据
Sandra Álvarez-Carretero1,2, Asif U Tamuri3,4, Matteo Battini5
1School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK.
Nature
|December 22, 2021
概括
一种新的贝叶斯方法分析了72种哺乳动物的基因组以创建物种级别的时间树. 这解决了有争议的胎盘哺乳动物进化时间表,将它们的起源置于白纪晚期.
科学领域:
- 进化生物学
- 基因组学
- 计算生物学
背景情况:
- 高通量测序产生了大量的基因组数据.
- 目前的贝叶斯时间树方法在计算上有限,阻碍了大数据集的分析.
- 哺乳动物的分子时钟分析产生了相互矛盾的年龄估计和很大的不确定性.
研究的目的:
- 开发一个贝叶斯分子时钟测年方法,用于大规模的基因组数据集.
- 使用72种哺乳动物基因组估计4,705种哺乳动物的时间树.
- 提高多元化时间估计的精度,以测试宏观进化假设.
主要方法:
- 开发了一种新的贝叶斯分子时钟测年方法.
- 综合了72种哺乳动物4705种基因组的数据.
- 应用该方法推断一个全面的哺乳动物时间树.
主要成果:
- 显示较大的基因组数据集可以减少多样化时间估计的不确定性.
- 坚定地拒绝了胎盘哺乳动物起源的爆炸性模型.
- 冠状胎盘的起源可以追溯到白纪晚期,在古世/新世时期有明显的顺序多样化.
结论:
- 新的贝叶斯方法使得对完整的基因组和数千个物种的分析成为可能.
- 这种方法解决了以前难以解决的物种多样化研究问题.
- 该方法适用于其他有争议的动物和植物多样化案例,需要物种级别的基因组数据.
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