机动运动的变化,笔脚的比例,以及 Synapsida 中的全度的演变
P J Bishop1,2, S E Pierce1
1Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA.
Anatomical record (Hoboken, N.J. : 2007)
|June 17, 2025
概括
突触四肢骨的比例揭示了运动和体重支的进化转变. 这些变化,特别是笔脚的比例,支持生物力学假设,但显示复杂的模式和马赛克进化.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 生物力学 生物力学
背景情况:
- 突触类动物的运动运动进化涉及显著的功能转变,包括从伸展到直立的肢体姿势的过渡.
- 骨结构是功能要求和进化适应的关键指标.
研究的目的:
- 为了研究突触骨和大腿骨比例的进化变化,以评估运动进化过程中的功能转变.
- 测试 stylopod 比例的变化是否与骨载荷,关节/肌肉力和四肢支的推断变化保持一致.
主要方法:
- 测量了来自330种突触体物种的936个腰骨和大腿骨的比例,跨越3200多万年.
- 开发了一种新的方法,用于计算特定物种,经大小校正的骨比例,以解开尺寸效应.
- 利用祖先状态的重建来分析尺寸纠正的笔足比例的演变.
主要成果:
- 经过大小校正的样脚体比例揭示了支持沿着therian血统的运动生物力学假设转移的趋势.
- 观察到复杂的转变模式,表明突触体进化中的功能马赛克.
- 在泰里亚王冠之前,通常不会达到泰里亚典型的笔脚动物比例;在非哺乳动物的类动物中注意到了逆转.
结论:
- 突触肢体骨比例的进化趋势在很大程度上支持主要的运动器生物力学转变.
- 功能性马赛克主义和暂时的趋势逆转凸显了synapsids,特别是非哺乳动物cynodonts内的运动运动进化和多样化的复杂性.
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