Doctoral Dissertation Research: An analysis of the evolution of shape change trajectories using 3D geometric morphometrics

在亲缘关系密切的动物物种中，生长和发育模式的差异往往是成年解剖结构差异的原因。这个博士论文项目将研究一些灵长类物种的颅骨解剖，考虑到生长和发育的轨迹，并使用这些数据来重建祖先物种的生长和发育轨迹。该项目将促进关于灵长类适应和生活史的知识，并将产生新的形状测量工具，用于研究生长、发育和解剖学，这些工具将在许多生物学学科中有用。本科生将参与形状测量的处理和分析，从而学习几何形态测量、数学和统计分析的技术技能。该项目还将支持公共科学推广活动，以便与更广泛的受众分享这些生物学概念和方法进步。这项研究的目的是研究进化如何塑造头面部的生长和发育，从而产生在卡他鼻目动物中观察到的形态多样性。几何形态计量学方法将被用来测量26种现存卡他目物种的个体发育颅骨序列，从中计算个体发育形状变化的轨迹。为了解决祖先的形态问题，这个项目将重建现存所有卡他类动物的最后一个共同祖先(LCA)的颅骨个体发育轨迹，以及脊椎动物、类人猿和古人类的LCA轨迹，以便将祖先的轨迹与现有类群的轨迹进行比较。由于成体形态在很大程度上是生长和发育模式的产物，这些祖先的个体发育轨迹将被用来确定成年卡他龙祖先的头骨形状。该项目还将通过评估大小是进化阻力最小的一条线的假说，解决头骨大小在成虫形态产生中的作用，即大小变化可能是适应和多样化的第一步，大小对环境变化的反应比形状更快。利用系统发育比较方法的最新进展，将通过直接比较卡他龙头骨中个体发育形状变化的矢量，并通过检查卡他鼻动物系统发育在颅骨大小进化和颅骨大小-形状关系中的比率变化来检验这一假说。这一奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

In closely related animal species, differences in patterns of growth and development are often responsible for differences in adult anatomy. This doctoral dissertation project will study cranial anatomy in a number of primate species, taking into account trajectories of growth and development, and use those data to reconstruct the growth and development trajectories of ancestral species. The project will advance knowledge about primate adaptation and life history, and will also generate novel shape measurement tools for studying growth, development and anatomy that will be useful across a number of biological disciplines. Undergraduate students will participate in the processing and analysis of shape measurements, thereby teaching them technical skills in geometric morphometrics, mathematics, and statistical analysis. The project will also support public science outreach activities to share these biological concepts and methodological advances with a broader audience. The objective of this investigation is to examine how evolution has shaped craniofacial growth and development to produce the morphological diversity observed in catarrhines. Geometric morphometric methods will be used to measure an ontogenetic cranial series of 26 extant catarrhine species, from which trajectories of ontogenetic shape change will be calculated. To address ancestral morphologies, this project will reconstruct the cranial ontogenetic trajectory of the last common ancestor (LCA) of all extant catarrhines, as well as those of the LCA of cercopithecoids, hominoids, and hominins, allowing for a comparison of ancestral trajectories with those of extant taxa. As adult morphologies are largely the product of patterns of growth and development, these ancestral ontogenetic trajectories will be used to make determinations about the cranial shapes of adult catarrhine ancestors. This project will also address the role of cranial size in the production of adult morphologies through an evaluation of the hypothesis of size as a 'line of least evolutionary resistance,' whereby size changes may be a first step in adaptation and diversification, with size responding more quickly than shape to environmental change. Using the latest advances in phylogenetic comparative methods, this hypothesis will be tested through direct comparisons of vectors of ontogenetic shape change in the catarrhine skull, and by examining the catarrhine phylogeny for rate shifts in the evolution of cranial size and in cranial size-shape relationships.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.