蛇牙的进化起源和发展
Freek J Vonk1, Jeroen F Admiraal, Kate Jackson
1Institute of Biology, Leiden University, Kaiserstraat 63, PO Box 9516, 2300 RA, Leiden, The Netherlands.
Nature
|August 1, 2008
概括
蛇的牙,无论是前面还是后面,很可能具有共同的进化起源. 一个发育转变允许后牙独立进化,这有助于蛇的多样性.
科学领域:
- 进化发育生物学 进化发育生物学
- 比较解剖学的比较解剖学.
- 类学 类学 类学 类学
背景情况:
- 先进的蛇拥有牙,特殊的牙与毒液腺相关,对于捕食和防御至关重要.
- 爪子被分为前置 (例如,蛇,毒蛇) 或后置 (例如,草蛇) 在上.
- 蛇进化的一个关键辩论是,前和后的共同进化和发育起源.
研究的目的:
- 为了研究蛇前后牙的进化和发育起源.
- 为了确定前和后是否是同类结构.
- 根据发育洞察力,提出蛇牙进化的新模型.
主要方法:
- 检查了8个物种96只蛇胚胎上下中的形成牙的表皮.
- 利用声波刺基因作为发育标记物.
- 在41个胚胎中使用3D成像技术重建了牙的发育.
主要成果:
- 前牙源于后上下,在发育上与后牙有相似之处,这表明它们具有同质性.
- 在前牙蛇中,发育过程将牙从后牙移到前牙的成年位置.
- 后牙从一个独立的后牙片中发展出来,保留了后部位置.
结论:
- 前和后可能是同类的,起源于一个共同的后部发育来源.
- 后牙形成区域的发育脱促进了牙的独立进化和修饰.
- 这种发育创新可能推动了先进蛇的显著辐射和多样性.
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