内部化石约束对皇冠古的年龄估计的影响比其他类型的基因组数据更大
Alexandre Pedro Selvatti1, Naoko Takezaki2
1Department of Zoology, Biology Institute, Rio de Janeiro State University - UERJ, Rio de Janeiro, Brazil.
Frontiers in bioinformatics
|August 25, 2025
概括
古代鸟类 (Palaeognathae) 的起源证实在白纪-古纪的边界附近,而不是伊纪. 这项研究使用基因组数据和强大的校准策略来澄清鸟类进化时间.
科学领域:
- 进化生物学
- 古遗传学
- 鸟类遗传学
背景情况:
- 一个古老的鸟类系,包括飞翔的鸟和六个无飞鸟群.
- 之前的研究提出了皇冠Paleognathae的相互矛盾的起源,大约在K-Pg边界 (66万年前) 或早期伊欧纪 (51万年前).
- 时间上的差异可能来自化石校准策略或所使用的基因组数据类型.
研究的目的:
- 调查校准策略和数据类型对Paleognathae的估计起源时间的影响.
- 为了解决围绕古老根的不确定性.
主要方法:
- 分析了来自14种古老动物的核 (非编码和编码) 和线粒基因组数据集.
- 内部校准和没有校准的年龄估计.
- 评估了不同校准策略和基因组数据类型对差异时间估计的影响.
主要成果:
- 年龄估计对校准策略比数据类型更敏感.
- 结果始终将Paleognathae王冠的起源放在K-Pg边界 (62-68万年前) 附近.
- 即使是之前暗示以纪时代的数据集也产生了K-Pg边界估计与修订的校准.
结论:
- 多个内部校准提供了对皇冠Paleognathae年龄的可靠和一致的估计.
- K-Pg边界起源增强了对早期鸟类进化和古世化石的理解.
- 这种精细的时间线有助于将Lithornithidae和Diogenornis等神秘的化石分配到皇冠Paleognathae内部的分支.
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