罗纪的哺乳动物形式和最早的哺乳动物进化适应
Chang-Fu Zhou1, Shaoyuan Wu, Thomas Martin
1Paleontological Museum of Liaoning, Shenyang Normal University, Shenyang, Liaoning 110034, China.
Nature
|August 9, 2013
概括
一个新的中罗纪化石揭示了哺乳动物的早期草食,早于皇冠哺乳动物. 这一发现突显了哺乳动物特征的起源,比如现代哺乳动物进化之前的特殊牙和毛皮.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 哺乳动物进化 哺乳动物进化
背景情况:
- 哺乳动物的特征起源于三叠纪和罗纪时期的灭绝的哺乳动物.
- 了解早期的哺乳动物进化为哺乳动物的起源提供了洞察力.
研究的目的:
- 为了描述一个新的中罗纪化石,表现出关键的哺乳动物特征.
- 调查草食动物和其他哺乳动物特征的进化时间表.
主要方法:
- 化石描述和解剖特征的分析.
- 与已知的哺乳动物和现存哺乳动物进行比较分析.
主要成果:
- 这种新化石具有下中耳,过渡性脊椎和原始的脚特征.
- 高度衍生的牙表明了专门的植物,这表明哺乳动物的早期草食形式.
- 牙的特征与eleutherodontid类结合在一起,以前只从孤立的牙中知道.
- 关于陆地动物运动和毛皮的证据表明,哺乳动物的整体外套早于现存哺乳动物的共同祖先.
结论:
- 在皇冠哺乳动物出现之前,草食动物进化为哺乳动物.
- 这一发现扩大了我们对类动物多样性和生态学的理解.
- 哺乳动物的关键特征,包括特殊的牙和牙,起源于进化史的早期.
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