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胎盘哺乳动物多样化的时间表,基于贝叶斯对化石记录的建模
Emily Carlisle1, Christine M Janis1, Davide Pisani2
1Bristol Palaeobiology Group, School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK.
Current biology : CB
|June 28, 2023
概括
胎盘哺乳动物起源于白纪晚期,在白纪-古人类大灭绝之前不久. 这种时间与分子钟估计相一致,并支持多样化模型重叠灭绝事件.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 生物地质年代学
背景情况:
- 胎盘哺乳动物辐射的进化时间尺度是有争议的,分子钟估计表明前白纪-古世 (K-Pg) 起源,与化石证据形成鲜明对比.
- 解读化石记录需要考虑其不统一性以及血统分歧和表型表达之间的延迟.
研究的目的:
- 开发一种新的统计模型,用于概率地解释化石记录,以估计进化起源和灭绝.
- 改进胎盘哺乳动物和它们的主要血统的估计起源时间.
主要方法:
- 介绍了一个扩展的贝叶斯布朗桥梁模型,用于概率的化石记录解释.
- 使用该模型估计起源和灭绝年龄.
主要成果:
- 胎盘哺乳动物起源于白纪晚期,在K-Pg边界或之后出现了顺序冠状群.
- 该模型将胎盘哺乳动物的起源间隔缩小到分子钟估计的年轻端.
- 调查结果支持长和软爆炸型多元化模式.
结论:
- 胎盘哺乳动物的起源发生在K-Pg大灭绝前不久.
- 许多现代哺乳动物血统的多样化跨越了K-Pg边界.
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