Doctoral Dissertation Research: Binocular Vision and the Primate Origins Hypotheses

所有现存的灵长类动物都有向前的眼睛，这提供了一个大的双目视觉和精确的深度感知。本论文项目将通过结合行为实验和活体灵长类动物的比较解剖学研究来测试灵长类动物双眼视觉进化起源的相互竞争的假设。该项目将建立一个可免费访问的哺乳动物不同样本CT扫描数据库，这将使研究人员和临床医生受益。研究人员将通过几个外展计划让公众参与这项工作，这些计划旨在提高公众对科学研究的理解，并为科学代表性不足的群体的学生参与STEM。该项目还将通过一个为第一代大学生和代表性不足群体的成员进行研究生研究做准备的方案，促进对几名本科生的培训。为了确定哪些生态因素导致了早期灵长类动物进化过程中广泛的双眼视觉的进化，该项目将采用比较形态学和实验方法。首先，研究人员将在生态和遗传多样性的比较哺乳动物样本中测量双眼视野，以确定哪些生态变量与哺乳动物双眼视野大小的增加相关。将通过液体保存样本的显微CT扫描测量双眼视野大小，该样本经碘染色以使眼睛的软组织可见。第二，研究人员将通过实验评估双眼视觉对抓取和跳跃行为类型的功能重要性，这些行为类型是竞争灵长类起源假说建议选择增加双眼视野宽度的。小型的夜间活动的链鼻怪将在正常条件下和双眼视野缩小的情况下进行抓取和跳跃任务。这种综合的方法来研究广泛的双目视觉领域的功能意义，将提供一个测试的竞争适应场景冠灵长类动物的起源。该项目的结果将有助于解决长期存在的关于灵长目动物的一个关键特征的争论。

All living primates have forward-facing eyes, which provide a large field of binocular vision and precise depth perception. This dissertation project will test competing hypotheses about the evolutionary origins of binocular vision in primates through a combination of behavioral experiments and comparative anatomical studies in living primates. The project will produce a freely accessible database of CT scans of a diverse sample of mammals, which will benefit researchers as well as clinicians. The investigators will engage the public in this work through several outreach programs aimed at increasing both public understanding of scientific research and participation in STEM for students from groups underrepresented in science. The project will also facilitate the training of several undergraduates through a program that prepares first generation college students and members of underrepresented groups for graduate research. To determine which ecological factors led to the evolution of a wide field of binocular vision during early primate evolution, this project will employ both comparative morphological and experimental methods. First, the investigators will measure binocular field in an ecologically and phylogenetically diverse comparative mammalian sample to determine which ecological variables are associated with increases in binocular field size across mammals. Binocular field size will be measured from micro-CT scans of fluid-preserved specimens that are iodine stained to render the soft tissues of the eyes visible. Second, the researchers will experimentally evaluate the functional importance of binocular vision for the types of grasping and leaping behaviors that competing primate origins hypotheses suggest selected for increased binocular field width. Small-bodied nocturnal strepsirrhines will be filmed performing grasping and leaping tasks under normal conditions and with reduced binocular visual field. This integrated approach to studying the functional significance of a wide field of binocular vision will provide a test of the competing adaptive scenarios for crown primate origins. The results of this project will help to address long-standing debates about a key feature of the primate order.