DISSERTATION RESEARCH: Geographic complexity in the recovery of terrestrial vertebrate assemblages from mass extinction

论文研究：陆地脊椎动物群从大规模灭绝中恢复的地理复杂性

• 批准号: 1501097
• 负责人: Christian Sidor
• 金额: $ 1.59万
• 依托单位: University of Washington
• 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: 2015-05-01 至 2017-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1501097&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Geographic; complexity; recovery

This project will improve our understanding of how terrestrial life diversified after the largest extinction event of the last 500 million years. This event took place just over 252 million years ago at the boundary between the Permian and Triassic periods, when more than 70% of terrestrial animals went extinct. The fossil record is one of the main sources of data for many questions concerning the history of life on Earth. For the end-Permian event, our understanding of what occurred on land is known almost entirely from just two places - Russia and South Africa. This new research will build a database of fossil material belonging to terrestrial vertebrate animals from two additional places - Tanzania and Zambia. Before the extinction the fossil communities at those two new locations were similar to those of South Africa, but afterwards they were very different, and included new animals such as close relatives of mammals and, surprisingly, early relatives of the first dinosaurs. This research will combine data collected from recent research with that stored in museums across Europe and Africa to develop the most extensive fossil database of end-Permian land animals. This will allow paleontologists to determine diversification patterns across a larger region than has ever been done for this time period, and to discover the reasons that particular species survived the largest mass extinction event of all time and subsequently thrived. This project will synthesize several facets of diversity among terrestrial tetrapods, including species richness, evenness, relative abundances, trophic structure, and ecological niche diversity, and adds a new component of geographical complexity from poorly-sampled basins in Tanzania and Zambia (TZAM). Substantial fieldwork there in recent years has confirmed that the sedimentary rocks can be correlated with those of South Africa and Russia, and can therefore act as independent tests of hypotheses about the extinction and recovery processes. Preliminary data indicate that a homogeneous fauna existed between TZAM and South Africa before the extinction event, but that during the recovery process ecosystems fragmented, resulting in increased levels of endemism and biogeographic differentiation. This project aims to test hypotheses related to ecological structure and biogeographic patterns of vertebrate communities on either side of the end-Permian extinction, both within and between basins. Additionally, the researchers will test in deep time an ecological hypothesis developed for extant species, the abundance-range hypothesis.

在过去5亿年的最大灭绝事件之后，该项目将提高我们对陆地生命如何多样化的理解。这一事件发生在二叠纪和三叠纪时期之间的边界上，当时超过70％的陆地动物灭绝了。化石记录是许多有关地球生命历史的问题的主要数据来源之一。对于哥伦比亚的最后活动，我们对土地上发生的事情的理解几乎完全来自两个地方 - 俄罗斯和南非。这项新的研究将建立一个来自陆地脊椎动物的化石材料的数据库，这些化石材料来自坦桑尼亚和赞比亚。在灭绝之前，这两个新地点的化石群落与南非的化石社区相似，但是之后它们非常不同，包括新动物，例如哺乳动物的近亲，以及令人惊讶的是第一批恐龙的早期亲戚。这项研究将将最近研究收集的数据与存储在欧洲和非洲的博物馆中的数据相结合，以开发最广泛的终点陆地动物的化石数据库。这将使古生物学家能够确定比这个时期更大的区域的多元化模式，并发现特定物种在有史以来最大的质量灭绝事件中幸存的原因并随后蓬勃发展。该项目将综合陆地四足动物之间多样性的几个方面，包括物种丰富，偶数，相对丰度，营养结构和生态利基多样性，并增加了坦桑尼亚和Zambia（TZAM）中较差的盆地的地理复杂性的新成分。近年来，那里的大量现场工作证实，沉积岩可以与南非和俄罗斯的岩石相关，因此可以作为对灭绝和恢复过程的假设的独立检验。初步数据表明，在灭绝事件发生之前，TZAM和南非之间存在均匀的动物群，但是在恢复过程中，生态系统分散，从而导致特征主义和生物地理学分化的水平增加。该项目旨在检验与脊椎动物社区的生态结构和生物地理模式有关的假设，无论是在底盆内和盆地之间和盆地内部灭绝的两侧。此外，研究人员将在深入的时间测试一个为现存物种开发的生态假设，即丰度范围的假设。