Doctoral Dissertation Research: The three-dimensional biomechanics of the grasping big toe among higher primates

转向两足行走，用两只脚直立行走，这是人类进化的一个标志，导致了抓握大脚趾(拇指)的适应性丧失。然而，人类两足运动的运动学先驱，以及这种变化发生的解剖学途径仍然知之甚少。为了更好地评估两足动物运动的进化，必须在更广泛的灵长类物种中检查脚部解剖和功能能力的变化。这个博士论文研究项目使用3D成像方法和计算机算法来检查一系列类人灵长类动物的足部解剖。产生的数据为现存和灭绝的猴子的足部形状的变异性以及我们祖先的运动过渡的解剖路径提供了信息。使用这种方法避免了对稀有标本的破坏，并制作了一个可免费访问的灵长类足部解剖的3D地图集。该项目支持STEM和K-12科学教育活动中的研究生培训和辅导。这项研究记录、描述、量化和比较了具有不同运动特长的猴子物种的幻觉肌的大小、方向和内部结构。这些方法将对比度增强成像与机器学习算法相结合。产生的信息允许在3D中开发准确和动态的足部解剖模型。在这项研究中开发的新的、非破坏性的工作流程将彻底改变在任何脊椎动物的其他复杂解剖系统中以3D方式重建肌肉骨骼生物力学的能力。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The shift to bipedal locomotion, walking upright on two feet, a hallmark of human evolution, resulted in the adaptive loss of the grasping big toe (hallux). However, the locomotive precursor of human bipedal locomotion, and the anatomic pathway through which this change occurred, remain poorly understood. To better assess the evolution of bipedal locomotion, changes in foot anatomy and functional capacity must be examined across a broader range of primate species. This doctoral dissertation research project uses 3D imaging methods and computer algorithms to examine foot anatomy across a range of anthropoid primate species. The data generated informs the variability of foot forms in living and extinct monkeys as well as the anatomical pathways of the locomotor transition of our ancestors. Using such methods avoids damaging rare specimens and produces a freely accessible 3D atlas of the primate foot anatomy. The project supports graduate student training and mentoring in STEM and K-12 science education activities. This study documents, describes, quantifies, and compares the size, orientation, and internal architecture of the hallucal muscles across monkey species that have diverse locomotive specializations. The methods combine contrast-enhanced imaging with machine learning algorithms. The information produced allows for the development of accurate and dynamic anatomic foot models in 3D. The novel, non-destructive workflow developed in this study stands to revolutionize the ability to reconstruct musculoskeletal biomechanics in 3D in other complex anatomical systems of any vertebrate animal.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.