DISSERTATION RESEARCH: Structure and Systematics of the Earliest Terrestrial Ground Cover

论文研究：最早陆地地被植物的结构和系统学

• 批准号: 0308806
• 负责人: Gar Rothwell
• 金额: --
• 依托单位: Ohio University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0308806&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Structure; Systematics; Earliest

A grant has been awarded to Dr. Gar Rothwell and Mr. Alexandru Tomescu at Ohio University to study the organisms that formed the earliest known terrestrial groundcover. Fossils of these organisms collected by the grantees in 445-435 million year old rocks of eastern North America (Virginia, Pennsylvania) represent the oldest unequivocal evidence for life on continents, out of the marine realm. The goal of their project is to characterize the structure of these early terrestrial organisms, and to clarify their biological relationships. To do this, they will isolate fossils from the rocks, prepare them, and investigate their structure employing light- and electron microscopy. They will then compare the fossil organisms to living groups, to clarify their biological and evolutionary relationships. Although the origin of life on land over 450 million years ago has been the subject of considerable research and much speculation, the nature of the earliest terrestrial organisms still ranks among the most crucial unanswered questions in modern life sciences. By investigating newly found fossils of the earliest terrestrial organisms, this project can address these questions, strongly impacting thinking and working hypotheses in evolutionary biology and earth sciences. By identifying the groups of organisms that were the first to colonize the continents, this work will provide much-needed direct evidence for the ancestors of early terrestrial colonizers, and for the initial patterns of evolution and diversification of life on land. Characterizing the first abundant land organisms also has important implications for global-scale interpretations of weathering process changes that resulted from the origin of terrestrial groundcover, and for the impact of these changes on continent-ocean chemical cycles.

俄亥俄州大学的Gar Rothwell博士和Alexandru Tomescu先生获得了一笔赠款，用于研究形成已知最早陆地地被的生物。这些生物的化石由受赠者在北美东部（弗吉尼亚州，宾夕法尼亚州）4.45 - 4.35亿年前的岩石中收集，是海洋领域之外大陆上生命最古老的明确证据。他们项目的目标是描述这些早期陆地生物的结构，并阐明它们的生物学关系。为了做到这一点，他们将从岩石中分离化石，准备它们，并使用光学和电子显微镜研究它们的结构。然后，他们将化石生物与生活群体进行比较，以澄清它们的生物学和进化关系。虽然4.5亿年前陆地上生命的起源一直是大量研究和猜测的主题，但最早的陆地生物的性质仍然是现代生命科学中最关键的未解之谜。通过调查新发现的最早的陆地生物化石，该项目可以解决这些问题，强烈影响进化生物学和地球科学的思想和工作假设。通过确定最早在大陆上殖民的生物群体，这项工作将为早期陆地殖民者的祖先以及陆地生命的最初进化模式和多样化提供急需的直接证据。描述第一批丰富的陆地生物也具有重要意义的全球尺度的解释风化过程的变化，导致陆地地面覆盖的起源，以及这些变化对大陆-海洋化学循环的影响。