Lewton Kristi L, Brankovic Ryan, Byrd William A, Cruz Daniela, Morales Jocelyn, Shin Serin
Department of Integrative Anatomical Sciences, University of Southern California, Los Angeles, CA, United States of America.
Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States of America.
PeerJ. 2020 Feb 20;8:e8574. doi: 10.7717/peerj.8574. eCollection 2020.
The mammalian pelvis is thought to exhibit adaptations to the functional demands of locomotor behaviors. Previous work in primates has identified form-function relationships between pelvic shape and locomotor behavior; few studies have documented such relationships in carnivorans, instead focusing on long bones. Most work on the functional morphology of the carnivoran pelvis, in particular, has used univariate measures, with only a few previous studies incorporating a three-dimensional (3D) analysis. Here we test the hypothesis that carnivoran taxa that are characterized by different locomotor modes also differ in 3D shape of the os coxae. Using 3D geometric morphometrics and phylogenetic comparative methods, we evaluate the phylogenetic, functional, and size-related effects on 3D pelvis shape in a sample of 33 species of carnivorans. Using surface models derived from laser scans, we collected a suite of landmarks ( = 24) and curve semilandmarks ( = 147). Principal component analysis on Procrustes coordinates demonstrates patterns of shape change in the ischiopubis and ilium likely related to allometry. Phylogenetic generalized least squares analysis on principal component scores demonstrates that phylogeny and body size have greater effects on pelvic shape than locomotor function. Our results corroborate recent research finding little evidence of locomotor specialization in the pelvis of carnivorans. More research on pelvic morphological integration and evolvability is necessary to understand the factors driving pelvic evolution in carnivorans.
哺乳动物的骨盆被认为展现出了对运动行为功能需求的适应性。先前在灵长类动物中的研究已经确定了骨盆形状与运动行为之间的形态-功能关系；而在食肉动物中，很少有研究记录此类关系，相反，这些研究主要关注长骨。特别是，大多数关于食肉动物骨盆功能形态学的研究都采用了单变量测量方法，之前只有少数研究纳入了三维（3D）分析。在这里，我们检验了这样一个假设：以不同运动模式为特征的食肉动物类群，其髋骨的三维形状也存在差异。我们使用三维几何形态测量学和系统发育比较方法，在33种食肉动物的样本中评估系统发育、功能和大小相关因素对三维骨盆形状的影响。利用从激光扫描获得的表面模型，我们收集了一组地标点（=24个）和曲线半地标点（=147个）。对普氏坐标进行主成分分析，揭示了耻骨坐骨和髂骨形状变化的模式，这些变化可能与异速生长有关。对主成分得分进行系统发育广义最小二乘法分析表明，系统发育和体型对骨盆形状的影响大于运动功能。我们的结果证实了最近的研究发现，即食肉动物骨盆中几乎没有运动特化的证据。有必要对骨盆形态整合和进化能力进行更多研究，以了解驱动食肉动物骨盆进化的因素。
