牙外的牙:金马的牙头的演变和发展
Karly E Cohen1,2, Michael I Coates3, Gareth J Fraser1
1Department of Biology, University of Florida, Gainesville, FL 32611.
概括
它们有着独特的面部牙. 这些口腔外的牙在内发育,更像是鱼口腔牙,而不是皮肤牙.
科学领域:
- 鱼类学
- 发育生物学
- 进化生物学
背景情况:
- 奇马鱼 (Holocephali) 是具有独特牙结构的软骨鱼,其中包括雄性牙.
- 坚固牙的进化起源和发育基础仍然不太清楚.
研究的目的:
- 研究斑点鼠鱼 (Hydrolagus colliei) 的和牙的生殖过程.
- 评估坚固的牙与口腔大的同质性和融合.
- 描述参与坚固牙发育的基因和组织.
主要方法:
- 在Hydrolagus colliei中详细分析牙和牙发育.
- 对坚固牙,口腔牙和皮肤牙进行比较分析.
- 结合碳期全头动物的化石证据的发育数据.
主要成果:
- 年轻的雄在牙发育完毕之前就形成了牙;成熟的雄有完全牙的牙.
- 形牙是从形牙中产生的,而不是周围的上皮.
- 牙的形状与鱼口腔牙有相似之处,而不是皮肤牙.
结论:
- 与上有着密切的联系.
- 牙可能代表一个不同的进化途径而不是修改的牙.
- 这项研究揭示了奇米拉独特的面发育和进化.
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