Doctoral Dissertation Research: Examining the Energetics Hypothesis for the Origin of Hominid Bipedalism

这项研究解决了一个假设，关于我们最早的原始人类祖先转向两足运动的性质。 要解决两足动物的起源是解决一个最基本的问题，这意味着什么是人类。尽管关于两足行走是否有助于定义人类家族人科存在争议，但很明显，成为两足行走是人类形态出现的关键第一步，先于所有其他主要的形态适应。从生物学和进化的角度来理解人类的意义，首先要理解两足动物的功能。 这项研究是一个两阶段的项目，旨在检验我们中新世祖先转向两足行走是由于与两足运动相关的能量节省的假设。 该项目涉及两个主要问题。 首先，黑猩猩两足行走时的能量消耗与四足行走时的能量消耗有多大的不同？ 为了解决这个问题，我们将测量一组不同性别的成年黑猩猩在跑步机上进行两足和四足运动时的能量消耗。 第二，目前测量自由放养的黑猩猩群体的日行程长度的方法是否系统地低估了这些动物的实际日行程距离？ 这将在为期6个月的实地研究中解决的自由放养的黑猩猩在Ngogo网站在基巴莱国家公园，乌干达，非洲习惯人口的日行程长度。 将采用四种测量日行程长度的方法，并与通过步速计数获得的测量值进行比较，以获得自由放养黑猩猩日行程长度的可测量值，并确定当前方法在多大程度上低估了实际的每日旅行距离。 这项研究的更广泛影响如下。 该项目将为本科生助理提供在研究生一级进行科学研究方法方面的经验、参与和培训的机会。本科助理将从加州大学农业、文学和科学本科研究人员导师计划（MURALS）的学生会员中招募。 MURALS为有兴趣在本科阶段获得研究生水平研究经验的代表性不足和少数族裔学生提供资金。 这项研究将在兽医学院和加州大学戴维斯分校人类学系之间建立重要的合作伙伴关系，为未来的跨学科研究奠定基础。 该项目还将在加州大学和“人与黑猩猩在一起”（People and Chimps Together，PACT）之间建立重要的伙伴关系，PACT是一个非营利组织，致力于照顾从医学研究和娱乐业工作中退休的黑猩猩。 该项目将协助PACT进一步建立一个教育设施，向公众介绍黑猩猩的行为和保护需求。这项研究对整个社会的好处包括对现代医疗保健的几个领域的潜在贡献，包括运动医学，兽医学和新兴的进化医学领域。 此外，了解我们起源的愿望在人类社会中无处不在。 这项研究将使人们更深入地了解这些起源。

This research addresses a hypothesis concerning the nature of the shift to bipedal locomotion in our earliest hominid ancestors. To address the origin of bipedalism is to address one of the most fundamental questions about what it means to be human. Though debate exists about whether bipedalism serves to define the human family, Hominidae, it is clear that becoming bipedal was the critical first step in the emergence of the human form, preceding all other major morphological adaptations. Understanding what it means to be human from a biological and evolutionary standpoint begins with understanding the functions of bipedalism. This study is a two-phase project designed to examine the hypothesis that the shift to bipedalism among our Miocene ancestors was due to energy savings associated with bipedal locomotion. The project addresses two primary questions. First, to what extent do energy costs during bipedal locomotion differ from energy costs during quadrupedal locomotion in chimpanzees? Answering this question will consist of measuring energy expenditure in a diverse set of adult chimpanzees of both sexes during bipedal and quadrupedal locomotion on a treadmill. Second, have current methods of measuring day journey length in free-ranging populations of chimpanzees systematically underestimated the actual daily travel distance of these animals? This will be addressed in a 6-month field study of day journey length in a habituated population of free-ranging chimpanzees at the Ngogo site in Kibale National Park, Uganda, Africa. Four methods of measuring day journey length will be employed and compared to measurements obtained through pace counting in order to obtain a defendable measure of day journey length for free-ranging chimpanzees and to determine to what extent current methods underestimate actual daily travel distance. The broader impacts of this research are as follows. This project will provide undergraduate student assistants with the opportunity for experience, participation and training in the methods of scientific research at the graduate level. Undergraduate assistants will be recruited from the student membership of the Mentorships for Undergraduate Researchers in Agriculture, Letters and Science (MURALS) program at the University of California. MURALS provides funding for under-represented and minority students interested in gaining experience doing graduate-level research while still at the undergraduate level. This research will establish important collaborative partnerships between the School of Veterinary Medicine and the Department of Anthropology at the University of California, Davis, laying the groundwork for future interdisciplinary studies. This project will also establish an important partnership between the University of California and People and Chimps Together (PACT), a non-profit organization dedicated to the care of chimpanzees retired from medical research and from work in the entertainment industry. This project will assist PACT in furthering the creation of an educational facility to introduce the public to the behavior and conservation needs of chimpanzees. The benefits of this research to society at large include potential contributions to several areas of modern health care including sports medicine, veterinary medicine and the emerging field of evolutionary medicine. Moreover, the desire to understand our origins is ubiquitous in human society. This research will provide a deeper understanding of those origins.