在最近的哺乳动物中,Laonastes和"拉撒路效应"
Mary R Dawson1, Laurent Marivaux, Chuan-Kui Li
1Section of Vertebrate Paleontology, Carnegie Museum of Natural History, 4400 Forbes Avenue, Pittsburgh, PA 15213, USA. dawsonm@carnegiemnh.org
Science (New York, N.Y.)
|March 11, 2006
概括
以前被认为属于自己的家族的老鼠Laonastes aenigmamus实际上是已灭绝的Diatomyidae家族的幸存成员. 这一发现突显了哺乳动物中的"拉撒路效应",在1100万年后再次被发现.
科学领域:
- 古生物学的古生物学
- 动物学 动物学
- 哺乳动物学 哺乳动物学
背景情况:
- 2005年发现的动物Laonastes aenigmamus最初因其独特的特征和明显的进化孤立而被归类为Laonastidae家族的唯一成员.
- 这种分类是基于形态特异性和现存动物中缺乏近亲的感知.
研究的目的:
- 重新评估Laonastes aenigmamus在动物类中的遗传学位置.
- 通过整合形态和分子数据来确定Laonastes aenigmamus的进化关系.
主要方法:
- 植物遗传学分析包括来自Laonastes aenigmamus和各种动物家族的形态和分子数据.
- 进行比较解剖学研究,以评估Laonastes aenigmamus与化石动物家族之间的关键诊断特征.
主要成果:
- 拉奥纳斯特 (Laonastes aenigmamus) 被重新归类为已灭绝的动物家族 (Diatomyidae) 的幸存成员.
- 在亚洲各地发现了Diatomyidae的化石,可以追溯到早期的奥利古纪到晚期的米奥纪.
- 这一发现代表了哺乳动物古生物学中的一个显著的"拉撒路效应",在1100万年缺席后,一个遗迹分类类重新出现.
结论:
- 现存的老动物Laonastes aenigmamus属于古老的Diatomyidae家族,而不是一个新的Laonastidae家族.
- 重新发现Diatomyidae突显了探索现存动物群的重要意义,以寻找以前仅从化石中已知的遗迹系.
- 这个案例提供了拉撒路效应的显著例子,证明了古代哺乳动物血统在广的地质时间尺度上的生存.
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