DISSERTATION RESEARCH: Inferring ecology in fossil terrestrial ecosystems

从吸血的吸血雀到以浮游生物为食的风暴海燕，鸟类是如何进化出惊人的生态多样性的，这仍然是一个没有答案的问题。鸟类骨骼很少被保存在化石记录中；即使它们存在，也很难推断出古代生态系统中灭绝物种的习性。在本博士论文项目中，研究者将通过比较灭绝鸟类的翅膀、腿和喙的形态与现代鸟类的形态，推断出灭绝鸟类的饮食和栖息地偏好。这些推论将在选定的物种中进一步测试，通过比较从形态学做出的预测与化石标本中保存的肠道内容物。最多样化的鸟类化石是在中国1.25亿年前的沉积物和北美和德国5000万年前的沉积物中发现的。通过将这些古代沉积物中鸟类的生态特征与这些地区今天和最近（100万年前）的鸟类特征进行比较，研究人员将对环境变化如何通过多样化和灭绝的过程对全球鸟类多样性做出贡献有更全面的了解。生物多样性受到物种灭绝率上升的威胁。这项研究的结果将把过去的环境变化与物种灭绝联系起来，为提高对未来物种灭绝率的预测提供有价值的历史信息。化石也是让学生和公众对科学感兴趣的最好方法之一。调查人员参加了芝加哥菲尔德自然历史博物馆的几个教育项目，带领人们参观化石收藏的“幕后”，并为小学教师开发地质学和地球历史方面的专业培训项目。本科生和高中生将参与这个项目，进行数据收集和分析。

How birds evolved their staggering ecological diversity, from vampire finches that drink blood to storm petrels that eat plankton, remains an unanswered question. Bird skeletons are infrequently preserved in the fossil record; when they are, it remains difficult to infer the habits of extinct species in ancient ecosystems. In this doctoral dissertation project, investigators will infer the diet and habitat preferences of extinct birds by comparing the morphology of their wings, legs, and beaks to that of modern birds. These inferences will be further tested in selected species by comparing the predictions made from morphology with the preserved gut contents of fossil specimens. The most diverse fossil bird assemblages are found in 125 million-year-old deposits in China and 50 million-year-old deposits in North America and Germany. By comparing the suite of ecological traits seen in birds from each of these ancient deposits with the suite seen in these localities today and in the recent past, (1 million years ago), the researchers will develop a more complete understanding of how environmental change has contributed to global bird diversity through the processes of diversification and extinction. Biodiversity is threatened by increasing rates of species' extinctions. Results from this study will link past environmental change with extinction, contributing valuable historical information to improve predictions of future extinction rates. Fossils are also one of the best ways to get students and the public interested in science. The investigators participate in several educational programs at the Field Museum of Natural History in Chicago, leading 'behind the scenes' tours of fossil collections and developing professional training programs in geology and earth history for elementary school teachers. Undergraduate and high school students will participate in this project with data collection and analysis.