RUI: Collaborative Proposal: Using Organic Carbon Isotopes of Single Microfossils to Illuminate Proterozoic Eukaryotic Ecosystems

RUI：合作提案：利用单一微化石的有机碳同位素来照亮元古代真核生态系统

基本信息

批准号：
1855014
负责人：
Phoebe Cohen
金额：
$ 7.96万
依托单位：
Williams College
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-04-01 至 2023-03-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1855014&HistoricalAwards=false
关键词：
RUI Collaborative Proposal Using Organic

项目摘要

Much about the early evolution of life on earth still remains a mystery, and while advances have been made in recent decades, major questions remain, especially about the relationships between biology and the rise of oxygen in the earth's atmosphere. Our proposal will measure organic carbon isotopes of microscopic fossils that represent our best window into the evolution of life before the rise of animals. These measurements will help us figure out where in the oceans early organisms were living and if early life could thrive in waters with little to no oxygen. This work will involve undergraduate students in every aspect of the research, analysis, and writing. We will create new geochemical and paleontological educational modules for K-12 and college educators, develop innovative organic geochemistry techniques that will be shared with the broader scientific community and add information on early fossil life to the open-access Paleobiology Database. While we have learned a significant amount about the Proterozoic Earth system in the last few decades, major questions remain, especially about the interplay between biology and the rise of atmospheric oxygen. One window into the biological record of the Proterozoic is via organic carbon isotopes, which track the isotope systematics of fixed carbon. However, these measurements are almost always done on bulk samples that represent the entire biological community time averaged into a sedimentary sample, which limits our ability to use these measurements to reconstruct short-term carbon cycle dynamics and to probe the structure of ancient ecosystems. Recent advances in NanoEA-IRMS now allow us to reliably measure the carbon isotopic composition of a single organic microfossil and compare that value to the bulk 13C. We seek to use this new technique to explore how organic carbon isotopes can illuminate two persistent unknowns in the Proterozoic Earth-life system: 1) What were the habitats and metabolisms of early eukaryotes? and 2) What can single microfossil carbon isotopes reveal about the controls on bulk carbon isotopes in the Proterozoic stratigraphic record and what do these records tell us about the Proterozoic Earth system?. We will approach these questions by analyzing bulk, kerogen and fossil organic carbon samples from four richly fossiliferous units that span the history of Proterozoic eukaryotes. The broader impacts of this proposal include continued development and refining of stable isotope analysis techniques, and integration of the Proterozoic microfossil record into the open-access Paleobiology Database. The proposal team will involve undergraduate students in all aspects of the research, and undergraduates will be meaningfully involved in data collection and interpretation. The team will also develop new educational activities for both high school and college-level audiences. The proposed work will include a postdoctoral fellow who will be mentored by all three PI's on research, professional development, and teaching.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

关于地球上生命的早期演变的很多很多仍然是一个谜，尽管近几十年来已经取得了进步，但仍然存在主要问题，尤其是关于生物学与氧气兴起之间地球大气中的关系。我们的建议将测量微观化石的有机碳同位素，这些碳代表着我们在动物兴起之前进入生命进化的最佳窗口。这些测量将帮助我们弄清楚早期生物在海洋中的生活，以及早期生命是否可以在几乎没有氧气的水域中繁衍生息。这项工作将涉及研究，分析和写作的各个方面。我们将为K-12和大学教育者创建新的地球化学和古生物学教育模块，开发创新的有机地球化学技术，这些技术将与更广泛的科学界共享，并将有关早期化石寿命的信息添加到开放式古代生物学数据库中。尽管在过去的几十年中，我们已经了解了有关元古代地球系统的大量知识，但仍然存在主要问题，尤其是关于生物学与大气氧的兴起之间的相互作用。进入元古代生物学记录的一个窗口是通过有机碳同位素来跟踪固定碳的同位素系统。但是，这些测量几乎总是在代表整个生物群落时间平均为沉积样本的整个样本上进行的，这限制了我们使用这些测量值重建短期碳循环动态并探测古代生态系统结构的能力。现在，纳米币的最新进展使我们能够可靠地测量单个有机微化石的碳同位素组成，并将该值与大量13C进行比较。我们试图使用这种新技术来探索有机碳同位素如何在proterreociac的地球生命系统中阐明两个持续的未知数：1）早期真核生物的栖息地和代谢是什么？ 2）单个微化石同位素可以揭示有关型型地层记录中块状碳同位素控制的控制，这些记录告诉我们有关proteroyoic oferoxoic Earth System的什么？我们将通过分析来自四个跨越植物真核生物史的四个丰富化石单元的散装，动菌和化石有机碳样品来解决这些问题。该提案的更广泛影响包括稳定的同位素分析技术的持续开发和精炼，以及将原始微化石记录的整合到开放式古生物学数据库中。建议团队将使本科生参与研究的各个方面，而本科生将有意义地参与数据收集和解释。该团队还将为高中和大学级别的受众开展新的教育活动。拟议的工作将包括一位博士后研究员，他将受到所有三个PI研究，专业发展和教学的指导。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的评估评估标准来通过评估来支持的。