Paleobiological and paleoenvironmental control on the origin and diversification of Late Ordovician and early silurian epicontinental brachiopod faunas of North America

古生物学和古环境对北美晚奥陶世和早志留世陆表腕足动物群起源和多样性的控制

基本信息

批准号：
217028-2008
负责人：
Jin, Jisuo
金额：
$ 2.55万
依托单位：
University of Western Ontario
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2011
资助国家：
加拿大
起止时间：
2011-01-01 至 2012-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=477867
关键词：
Paleobiological paleoenvironmental control origin diversification

项目摘要

A major concern about the global warming today is its effect on sea level rise and biodiversity change. The study of modern global change in climate and biodiversity is confined to the scale of decade to millennium. Paleontologists investigate environmental and biodiversity changes in Earth history at a million-year scale based on fossil record preserved in sedimentary rocks. During the past 530 million years (myr) of the Phanerozoic Earth history, one of the two grandest episodes of global warming and sea-level rise occurred in Late Ordovician-Early Silurian time (460-430 myr ago), when the North American paleocontinent was flooded by epicontinental seas, in which marine life thrived, with brachiopods being the dominant benthic shelly organisms. In this proposal, the rich brachiopod fossil records of North America will be studied to address several key questions regarding the epicontinental marine shelly faunas: 1) How did the epicontinental brachiopod faunas originate, disperse, and diversify during the global warming and marine transgression? 2) Why did the epicontinental brachiopod faunas become isolated during the Late Ordovician marine transgression but not during the Early Silurian episode? and 3) What environmental and biological factors controlled the differentiation of contemporaneous brachiopod faunas and the temporal fluctuations in biodiversity during the Late Ordovician-Early Silurian? The approach to these questions is to compare the brachiopod faunas between continental-margin seas (e.g. Anticosti Basin, Mackenzie Mountains, Arctic Canada) and inland basins (Hudson Bay, Michigan, and Williston basins), and by tracing the morphological changes in several brachiopod lineages and their paleoecological settings, using cladistic and multivariate analyses. Results from the proposed research can help us better understand modern global change from the perspective of million year-scale global warming and biodiversity change that occurred in ancient Earth history.

当今全球变暖的一个主要问题是它对海平面上升和生物多样性变化的影响。现代全球气候和生物多样性变化的研究仅限于十年到千年的尺度。古生物学家根据沉积岩中保存的化石记录，研究百万年尺度的地球历史中的环境和生物多样性变化。在过去5.3亿年的显生宙地球历史中，全球变暖和海平面上升的两次最重大事件之一发生在奥陶世晚期-志留世早期（距今460-430马耳），当时北美古大陆被陆缘海洋淹没，海洋生物繁衍生息，其中腕足动物是主要的底栖有壳生物。在本提案中，将研究北美丰富的腕足动物化石记录，以解决有关陆表海洋贝类动物群的几个关键问题：1）在全球变暖和海洋侵入期间，陆表腕足动物群是如何起源、分散和多样化的？ 2）为什么陆表腕足类动物群在晚奥陶世海侵期间被隔离，而在早志留世却没有被隔离？ 3）晚奥陶世-早志留世，哪些环境和生物因素控制了同时代腕足动物区系的分化和生物多样性的时间波动？解决这些问题的方法是比较大陆边缘海（例如安蒂科斯蒂盆地、麦肯齐山脉、加拿大北极）和内陆盆地（密歇根州哈德逊湾和威利斯顿盆地）之间的腕足动物区系，并追踪几种腕足动物的形态变化使用分支和多元分析来研究谱系及其古生态环境。这项研究的结果可以帮助我们从古代地球历史上发生的百万年规模的全球变暖和生物多样性变化的角度更好地理解现代全球变化。