Doctoral Dissertation Research: Binocular Vision and the Primate Origins Hypotheses

所有现存的灵长类动物的眼睛都是朝前的，这提供了大范围的双眼视觉和精确的深度感知。本论文项目将通过对现存灵长类动物的行为实验和比较解剖学研究相结合，来检验关于灵长类动物双目视觉进化起源的竞争性假设。该项目将建立一个免费访问的各种哺乳动物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项目让公众参与这项工作，旨在增加公众对科学研究的理解，并让来自科学领域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成员准备研究生研究的项目，促进对几名本科生的培训。为了确定在早期灵长类动物进化过程中，哪些生态因素导致了广阔的双眼视觉的进化，本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系统发育不同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有关。双眼视野大小将通过对液体保存标本的微ct扫描来测量，这些标本被碘染色以使眼睛的软组织可见。其次，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，这些行为与灵长类动物起源假说相竞争，认为选择了增加的双眼视野宽度。小型夜行性链球菌将在正常条件下和双目视野缩小的情况下进行抓取和跳跃任务的拍摄。这种综合的方法来研究大视野双目视觉的功能意义，将为灵长类动物起源的竞争适应情景提供一个测试。这个项目的结果将有助于解决长期以来关于灵长类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.