牙骨和牙置换的起源
Donglei Chen1, Henning Blom1, Sophie Sanchez2,3
1Uppsala University, Department of Organismal Biology, Norbyvägen 18A, SE-752 36 Uppsala, Sweden.
Nature
|November 4, 2016
概括
牙脊椎动物有不同的牙置换机制. 一个有4.24亿年历史的化石鱼,Andreolepis hedei,通过再吸收显示了早期的牙脱落,为脊椎动物的牙进化提供了洞察力.
科学领域:
- 古生物学
- 进化生物学
- 脊椎动物学
背景情况:
- 脊椎动物的牙置换模式是多样化的,对牙的维护至关重要.
- 像牙膜和牙脱落等机制在现存物种中分布不均.
- 了解原始牙替代是追踪脊椎动物牙演变的关键.
研究的目的:
- 为了研究古老的骨科动物Andreolepis hedei的牙置换机制.
- 为了重建Andreolepis牙的生长历史和脱落过程.
- 确定骨质动物中最早出现的吸收性牙脱落.
主要方法:
- 使用传播相对比的同步光子微解剖三维虚拟解剖.
- 对Andreolepis hedei的牙结构进行详细分析.
- 牙生长和更换史的重建.
主要成果:
- 一个早期的骨质动物,通过基底硬组织再吸收而脱落牙.
- 这种化石很可能没有永久的牙膜,
- 这是最早记录的吸收性牙脱落的证据.
结论:
- 吸收性牙脱落可能是骨质动物牙替换的原始方式.
- 提供了关于脊椎动物牙早期演变的关键见解.
- 这些发现挑战了关于牙置换机制的先行性假设.
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