逆向工程一个干胚胎的运动
John A Nyakatura1,2, Kamilo Melo3, Tomislav Horvat3
1AG Morphologie und Formengeschichte, Institut für Biologie, Humboldt Universität zu Berlin, Berlin, Germany. john.nyakatura@hu-berlin.de.
Nature
|January 18, 2019
概括
重建已灭绝的干胚胎 Orobates pabsti 的运动,揭示了先进的陆地运动. 这表明复杂的陆地运动是在冠状羊生物多样化之前演变的.
科学领域:
- 古生物学
- 脊椎动物的进化
- 生物力学
背景情况:
- 重建已灭绝的脊椎动物的运动对于理解古生物学和主要的进化转变至关重要.
- 由于化石证据有限和形式功能断开,估计化石运动行为具有挑战性.
- 先进的陆地运动通常与胚胎多样化有关,但其在茎胚胎的起源尚不清楚.
研究的目的:
- 使用多种方法量化重建茎胚胎的步态.
- 为了确定Orobates是否表现出先前与皇冠胚胎相关的高级运动特征.
- 研究与胚胎多样化的先进陆地运动的进化时间表.
主要方法:
- 结合现存四足动物的生物机械相关指标的综合方法.
- 在四种现存物种中使用 in vivo 运动力学评估,用于 Orobates 的动力学模拟.
- 包含动态模拟和机器人来过可信的步态, 通过两种现存物种进行验证.
主要成果:
- 定量分析表明,Orobates pabsti比以前认为的早期四足动物具有更先进的运动能力.
- 经过重建的奥罗巴特的步态与其相关的化石轨道保持一致.
- 这些发现表明先进的陆地运动早于冠状胚胎的多样化.
结论:
- 欧罗巴特斯帕斯蒂证明,复杂的陆地运动在脊椎动物的历史中比以前认为的要早.
- 先进的陆地运动并不仅限于早期的胚胎动物,而且很可能起源于茎胚胎动物.
- 这项研究为未来的化石运动行为重建提供了一个框架,允许进行方法修订.
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