Doctoral Dissertation Research: Trabecular and cortical skeletal correlates to locomotor ontogeny in hominoids

人类骨骼的生长和发育受到整个生命过程中使用骨骼的方式的影响。为了了解人类骨骼发育的进化过程，研究其他近亲灵长类动物的骨骼发育是有用的。这个博士论文项目的目标是研究黑猩猩生命过程中运动的变化是如何反映在骨骼上的。黑猩猩在年轻时主要在树上活动，而随着年龄的增长，它们更多地在地面上活动，这为研究黑猩猩的小梁骨（海绵状）和皮质骨（致密）是如何随着生命过程中运动的变化而改变提供了一个机会。这项研究将有助于我们对骨骼生物学的理解，特别是骨骼对整个生命运动变化的敏感性，这可以用来更好地重建已灭绝的猿类和人类化石的运动，特别是陆地生物的进化。该研究将用于K-12科学宣传，并在自然博物馆展出。泛穴居人化石和人猿化石的CT扫描和3D打印也将成为猿类进化和保护国际展览的一部分。该项目生成的所有CT扫描将与收集数据的博物馆共享，进一步促进科学访问和探究。骨骼是化石记录中重要的数据来源，因为它们在运动过程中（如走路、跑步、攀爬）受到机械负荷的影响而发生变化。然而，到目前为止，大多数研究都集中在小梁骨或皮质骨上，而不是在一项研究中同时研究两者。黑猩猩改变了它们的生活方式，从婴儿期到成年期，从更多的树栖到更多的陆地栖。因此，如果骨骼对这些变化有反应，研究人员假设这些转变将在小梁骨和皮质骨中被检测到。这项研究还将探讨两种骨骼类型在发育过程中是否会对运动变化做出反应，并将这些发现应用于其他物种，无论是现存的还是化石的，以帮助恢复运动模式和基质使用。这些问题将通过对前肢和后肢小梁骨的微ct扫描以及对股骨、胫骨、肱骨和桡骨的皮质骨的pQCT扫描来解决。预测每个生活史阶段的小梁骨和皮质骨会反映当时使用的运动行为。通过进一步研究个体发生行为变化与骨皮质和骨小梁结构之间的关系，可能会发现新的对负荷模式敏感的解剖学代理，并用于重建化石猿和人类的运动技能。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The growth and development of the human skeleton is affected by the way it is used across the life course. In order to understand how human skeletal development evolved, it is useful to study skeletal development in other closely related primates. The goal of this doctoral dissertation project is to investigate how changes in locomotion across the chimpanzee life course are reflected in the skeleton. Chimpanzees change from moving mostly in the trees when they are young to moving more on the ground as they age, providing an opportunity to examine how chimpanzee trabecular (spongy) and cortical (compact) bone are modified as locomotion changes across the life course. The research will contribute to our understanding of bone biology, specifically the sensitivity of the skeleton to changes in movement throughout life, which can be used to better reconstruct the locomotion of extinct fossil apes and humans, particularly the evolution of terrestriality. This research will be used in K-12 science outreach and exhibited at natural history museums. CT scans and 3D prints of Pan troglodytes and fossil hominoids (apes) will also be part of an international exhibit focused on ape evolution and conservation. All CT scans generated from this project will be shared with the museums where the data were collected, furthering scientific access and inquiry. Bones are a crucial source of data from the fossil record because they undergo modification in response to the mechanical loads placed upon them during movement (e.g. walking, running, climbing). However, most studies to date focus on either trabecular or cortical bone and not the two together in one study. Chimpanzees modify how they move through their life, shifting from more arboreal to more terrestrial substrates from infancy to adulthood. Thus, if the skeleton is responding to these changes, the investigators hypothesize that these transitions will be detectable in trabecular and cortical bone. This study will also address whether both bone types respond to locomotor changes during development, and will apply these findings to other species, extant and fossil, to help in recovering patterns of movement and substrate usage. These questions will be addressed using microCT scans of trabecular bone in the fore- and hindlimb as well as pQCT scans of cortical bone in the shaft of the femur, tibia, humerus, and radius. The prediction is that trabecular and cortical bone at each life history stage will reflect the locomotor behaviors used at that time. By further studying the relationship between ontogenetic changes in behavior and cortical and trabecular bone structure, novel anatomical proxies sensitive to loading patterns may be identified and used to reconstruct the locomotor repertoires of fossil apes and humans.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.