DISSERTATION RESEARCH: Carnivory in the Oligo-Miocene: Dietary community ecology and diversity dynamics of large mammalian predators

论文研究：渐中新世的食肉动物：大型哺乳动物捕食者的饮食群落生态和多样性动态

基本信息

批准号：
1501931
负责人：
Blaire Van Valkenburgh
金额：
$ 2万
依托单位：
University of California-Los Angeles
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2015
资助国家：
美国
起止时间：
2015-06-01 至 2018-11-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1501931&HistoricalAwards=false
关键词：
DISSERTATION RESEARCH Carnivory Oligo Miocene

项目摘要

Competition is a common explanation for why carnivorous mammals differ in ecology, structure, and function. Over long time scales, it may also explain how current carnivore communities assembled. Dogs (wolves, jackals, foxes, coyotes, domestic dogs) originated in North America 40 million years ago but initially comprised primarily small raccoon-like forms. Although dogs later grew into one of the most diverse carnivore groups, they became large and carnivorous only in the Oligocene and Miocene epochs, 20 million years into their history - why? As the smaller early dogs lived alongside potentially large carnivore competitors - bears, bear-dogs, false saber-toothed cats, and weasels and allies - the North American Oligo-Miocene presents an ideal system to investigate how competition may have shaped, even suppressed, the initial diversification of a group. Inferring competition in the fossil record is difficult and depends on reconstructing body size and diet from dental and skeletal remains. To do so, this project will use both linear measurements and dental complexity analysis, a new technique that quantifies tooth surfaces using geographic information systems measures. Dental complexity captures the texture of teeth adapted for different diets, ranging from herbivory to carnivory. Combined, these approaches allow the classification of extinct species into body size and dietary types. This can then be used to quantify the potential for competition between dogs and other carnivorous mammals throughout their early evolutionary history. Studying early dogs and their potential competitors will aid understanding of current carnivore communities at this time of accelerated global change.

竞争是肉食哺乳动物在生态、结构和功能方面存在差异的常见解释。从长远来看，它也可以解释当前的食肉动物群落是如何聚集的。狗（狼、豺狼、狐狸、土狼、家犬）起源于 4000 万年前的北美，但最初主要由类似浣熊的小型动物组成。尽管狗后来成长为最多样化的食肉动物群体之一，但它们只是在渐新世和中新世时期（距今 2000 万年）才变得大型和肉食性 - 为什么？由于较小的早期犬类与潜在的大型食肉动物竞争对手——熊、熊狗、假剑齿虎、黄鼠狼和盟友——生活在一起，北美寡-中新世提供了一个理想的系统来研究竞争如何塑造甚至抑制集团最初的多元化。推断化石记录中的竞争很困难，并且取决于从牙齿和骨骼遗骸中重建身体尺寸和饮食。为此，该项目将使用线性测量和牙齿复杂性分析，这是一种使用地理信息系统测量来量化牙齿表面的新技术。牙齿的复杂性捕捉了牙齿适应不同饮食的纹理，从草食性到肉食性。结合起来，这些方法可以将灭绝物种按体型和饮食类型进行分类。然后，这可以用来量化狗和其他肉食哺乳动物在整个早期进化史上的竞争潜力。研究早期的狗及其潜在的竞争对手将有助于了解当前全球变化加速时期的食肉动物群落。