拉戈莫尔法树干和 Glires 的古老性
Robert J Asher1, Jin Meng, John R Wible
1Museum für Naturkunde, Humboldt Universität, Invalidenstrasse 43, 10115 Berlin, Germany. robert.asher@museum.hu-berlin.de
Science (New York, N.Y.)
|February 19, 2005
概括
来自蒙古的Gomphos elkema化石显示它是一种早期的形动物,是子和皮卡的祖先. 这一发现澄清了白纪-第三纪边界附近哺乳动物的纪辐射.
科学领域:
- 古生物学的古生物学
- 哺乳动物进化 哺乳动物进化
- 生物分层学是生物分层学.
背景情况:
- 形动物 (子,子,皮卡) 是关键的胎盘哺乳动物,化石记录稀少.
- 了解它们的进化起源对于重建早期代哺乳动物多样化至关重要.
研究的目的:
- 为了描述来自蒙古的新的Gomphos elkema化石.
- 确定Gomphos在胎盘哺乳动物中的遗传位置.
- 为了调查形动物和动物分歧的时间.
主要方法:
- 化石描述和Gomphos elkema的比较解剖学.
- 使用骨特征进行了家族遗传学分析.
- 化石沉积物在古世 - 世边界附近的生物层级测年法.
主要成果:
- 在蒙古的Tsagan Khushu发现了Gomphos elkema化石,可以追溯到古世 - 世边界.
- 戈莫斯表现出现代形动物的特征,但保留了原始的牙和结构.
- 遗传学分析将Gomphos定位为一个茎形体,早于皇冠群辐射.
结论:
- Gomphos elkema代表了一个早期的形动物,为该群体的起源提供了洞察力.
- 这些发现支持了在古新纪时代存在形动物和动物辐射的假设.
- 胎盘哺乳动物的分歧,包括形动物,可能发生在白纪-第三纪边界附近.
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