在一个化石中,配对的状裂具有石灰岩骨架
Patrício Dominguez1, Antone G Jacobson, Richard P S Jefferies
1Department of Palaeontology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
Nature
|June 21, 2002
概括
化石皮动物Jaekelocarpus oklahomensis,以前认为缺乏辐射对称性,拥有内部沟裂. 这一发现完善了我们对早期乳腺体进化和骨发育的理解.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 比较解剖学的比较解剖学
背景情况:
- 德乌特奥斯托米亚 (Deuterostomia),包括带动物,半带动物和皮动物,是一个成熟的单体动物群.
- 皮动物通常表现出射线对称性,并拥有石骨,但化石形式有时缺乏射线对称性.
- 来自上碳期的化石Jaekelocarpus oklahomensis,在外部几乎是双边对称的,传统上被放置在米特拉塔群中.
研究的目的:
- 为了研究Jaekelocarpus oklahomensis的内部解剖学和功能形态学.
- 为了澄清Jaekelocarpus oklahomensis在Deuterostomia中的遗传学位置.
主要方法:
- 计算机X射线微图学被用来检查Jaekelocarpus oklahomensis的详细解剖学.
- 功能解剖学是根据详细的解剖学数据来解释的.
主要成果:
- 对Jaekelocarpus oklahomensis的详细内部解剖学进行了揭示,超过了之前的描述.
- 在Jaekelocarpus oklahomensis内部发现了配对沟裂的证据.
- 对Jaekelocarpus oklahomensis的功能解剖学进行了解释.
结论:
- 尽管外在双边对称,但Jaekelocarpus oklahomensis 拥有内部沟,挑战了传统的分类.
- 这些发现表明Jaekelocarpus oklahomensis在Deuterostomia的修订后遗传位置.
- 这项研究有助于了解早期deuterostomes中的骨结构和对称性的多样性和进化.
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