马达加斯加的白纪哺乳动物的骨架反映了长期的孤岛生活
David W Krause1,2, Simone Hoffmann3, Yaoming Hu4
1Department of Earth Sciences, Denver Museum of Nature and Science, Denver, CO, USA. David.Krause@dmns.org.
Nature
|May 29, 2020
概括
发现了马达加斯加的Adalatherium hui化石骨, 揭示了人们对早期哺乳动物Gondwanatheria群体的了解. 这一发现为它们的解剖学和进化关系提供了关键的见解.
科学领域:
- 古生物学
- 脊椎动物古生物学
- 中纪哺乳动物
背景情况:
- 与劳拉西亚相比,冈瓦那的中生代哺乳动物化石记录很少.
- 贡德瓦纳特里亚是一个鲜为人知的中生代哺乳动物类,化石证据有限.
- 之前发现的Gondwanatheria主要是单独的牙和下巴碎片.
研究的目的:
- 描述一个新的,特别保存的Gondwanatherian哺乳动物的骨架.
- 为了阐明Gondwanatheria的解剖学,古生物学和遗传学位置.
- 调查冈多瓦哺乳动物的进化历史和独特的适应性.
主要方法:
- 挖掘和准备一个完整的,关节化化石骨.
- 对骨和骨后部件进行详细的解剖分析.
- 将新分类体纳入类型遗传学分析,以确定其进化关系.
主要成果:
- 在马达加斯加的白纪晚期发现了Adalatherium hui,一种新的Gondwanatherian属和物种.
- 该标本是迄今为止发现的最完整的冈多瓦中生代哺乳动物骨,包括关键的脑后物质.
- 植物遗传学分析认为Gondwanatheria是Multituberculata的姊妹群.
- 阿达拉表现出独特的原始和therian融合特征,表明长期的隔离.
结论:
- 亚达拉代表了对冈多瓦的哺乳动物形式多样性和进化的理解的重要补充.
- 阿达拉的独特特征凸显了冈瓦纳的独特进化路径,特别是在像马达加斯加这样的孤立陆地.
- 这些发现支持了Gondwanatheria是Multituberculata的姐妹分类,提炼了哺乳动物的分类.
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