伪tribosphenic和tribosphenic哺乳动物中的融合牙适应
Zhe-Xi Luo1, Qiang Ji, Chong-Xi Yuan
1Carnegie Museum of Natural History, Pittsburgh, Pennsylvania 15213, USA. luoz@carnegiemnh.org
Nature
|November 2, 2007
概括
一种新发现的中罗纪哺乳动物展示了先进的伪tribosphenic牙与原始的骨特征一起,挑战了早期哺乳动物进化的先前概念. 这一发现突显了中生代哺乳动物多样化的牙适应.
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:
- 三角牙是基底有袋动物和胎盘动物的关键适应,有助于粉碎和研磨.
- 已灭绝的伪tribosphenic哺乳动物具有一个反向的状结构,前面的伪talonid接收一个伪protocone.
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