Doctoral Dissertation Research: Evolution and development of the hominoid spine

在灵长类动物中，人类有许多独特的适应性，包括两足行走（用两条腿走路）的标志性特征，它塑造了我们移动的方式以及我们如何设计我们的建筑环境。两足动物的起源，包括导致两足动物的选择性压力和发育变化，还没有得到很好的理解。本论文研究脊椎发育在灵长类动物和哺乳动物中的作用，以更好地了解脊椎进化导致两足动物的方式。项目数据将用于扩大和创建宾夕法尼亚州立大学马特森人类学博物馆关于原始人两足行走和进化发育生物学起源的博物馆展览。科学推广活动也将通过宾夕法尼亚州立大学的学校科学中心进行，将STEM研究经验带给服务不足的K-12学生群体。 该项目还将支持在人类学和发展实验室技术方面对女本科生进行培训和指导，并为这些学生提供在会议上发言和共同撰写论文的机会。胸腰椎对于理解灵长类动物的进化和人类两足动物的起源和独特采用至关重要。类人猿和人类都通过移行椎的后移和无肋腰椎的复位来稳定脊柱。关于这些特征是同源的还是同质的，以及两足动物是从像类人猿那样的短而僵硬的背部进化而来，还是从更长的腰椎进化而来，这一点存在争议。研究人员建议比较博物馆收藏的灵长类动物过渡椎骨和实验改造小鼠的形态。 将使用3D和micro-CT扫描以及大型骨骼学数据集对灵长类动物博物馆标本和Hox 9改良小鼠胸椎和腰椎进行定量和定性分析。这些分析将解决两个重要的问题：1）胸腰椎过渡模式是否在猿类之间相似，以及2）各种胸椎和腰椎特征的发育独立性。这两个都是解决关于类人脊椎进化的争论所必需的。

Humans have many unique adaptations among primates, including the hallmark feature of bipedalism (walking on two legs) that shapes the way we move and how we design our built environment. The origins of bipedalism, including selective pressures and developmental changes that led to bipedalism, are not well understood. This dissertation project investigates the role of spine development in primates and mammals to better understand the way that spine evolution led to bipedalism. Project data will be used to expand and create museum exhibits about the origins of hominid bipedalism and evolutionary developmental biology in the Penn State Matson Museum of Anthropology. Science outreach activities will also be conducted through Penn State's Center for Science in the Schools, to bring STEM research experiences to underserved K-12 student populations. The project will also support training and mentoring of female undergraduate students in anthropological and developmental laboratory techniques, and provide opportunities for these students to present at conferences and co-author papers.The thoracolumbar spine is crucial for understanding primate evolution and the origins and unique adoption of human bipedalism. Both great apes and humans have stabilized their spine with the posterior shift of the transitional vertebra and reduction of non-ribbed lumbar vertebra. There is debate regarding whether these features are homologous or homoplastic, and thus whether bipedalism evolved from a short stiff back like great apes or a longer lumbar column more similar to monkeys and Miocene hominoids. The investigators propose to compare the morphology of the primate transitional vertebra in museum collections and experimentally modified mice. Quantitative and qualitative analyses will be conducted on primate museum specimens and Hox9 modified mouse thoracic and lumbar columns using 3D and micro-CT scanning and a large osteological dataset. These analyzes will address two important questions: 1) whether patterns of the thoracolumbar transition are similar across apes, and 2) the developmental independence of various thoracic and lumbar vertebral features. Both are necessary for resolving debate regarding the evolution of the spine in hominoids.