Collaborative Research: Unearthing Antarctica's role in the Late Cretaceous Evolution of Flowering Plants

合作研究：揭示南极洲在白垩纪晚期开花植物演化中的作用

• 批准号: 1953993
• 负责人: Brian Atkinson
• 金额: $ 48.89万
• 依托单位: University of Kansas Center for Research Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1953993&HistoricalAwards=false
• 关键词: Collaborative; Research; Unearthing; Antarctica; role

Part I: Nontechnical DescriptionFlowering plants are the dominant land plant group on Earth today. They play essential roles in climate-life interactions and are fundamental for human well-being (health, food, materials). Despite their importance to us, their early evolution has remained enigmatic. Without the geological context of how these plants evolved, we will not fully understand their roles in regulating climate and structuring environments. This is important as terrestrial ecosystems today are undergoing many changes. The fossil record indicates that critical events relating to the early diversification of flowering plants occurred during the Cretaceous period (145–66 million years ago). Recent discoveries of fossil flowers and fruits from this time period have significantly furthered our understanding of early flowering plant evolution. However, the majority of these discoveries are from the Northern Hemisphere while similar discoveries from the Southern Hemisphere are relatively lacking. This project will address this paucity of data by collecting and describing Late Cretaceous flowering plant fossils from Western Antarctica and placing them in evolutionary frameworks to better understand early flowering plant evolution, biogeographic history, and Antarctica’s role in the formation of modern ecosystems. Western Antarctica is the only place in the Southern Hemisphere that is reported to contain Late Cretaceous-aged (100–66 million years ago) three-dimensionally preserved flowers and fruits. Therefore, the recovery and study of these fossils can meaningfully further our understanding of the early phases of flowering plant evolution. This work will result in the description of new species that will be placed in evolutionary analyses and biogeographic frameworks, which will help clarify the Cretaceous diversification of flowering plants in the Southern Hemisphere. These fossils will provide insights that will allow us to anticipate which plants might thrive in a warming Antarctic and world.Part II: Technical DescriptionThe Late Cretaceous diversification of flowering plants (angiosperms) in the Southern Hemisphere is poorly understood due in part to the limited amount of well-characterized fossil plant reproductive structures. Paleobotanical studies indicate that Antarctica was an important area for the Cretaceous diversification of flowering plants and is the only place in the Southern Hemisphere that is known to contain permineralized Late Cretaceous-aged angiosperm reproductive structures. The proposed research will elucidate Antarctica’s role in the evolution of angiosperms and assembly of modern ecosystems by recovering and characterizing Late Cretaceous Antarctic angiosperms, placing them within a phylogenetic context, and testing for biogeographic links between North America and Gondwana as has been observed for animals. Fieldwork will be conducted in the James Ross Basin of West Antarctica where previous reports and preliminary data indicate the presence of Late Cretaceous-aged floras that include structurally preserved reproductive structures. The exceptional preservation of these fossils allows us to record data essential for placing them in a phylogenetic framework from which their evolutionary and biogeographical context can be determined. The taxonomically informative and well-preserved angiosperm reproductive structures within the James Ross Basin are of a crucial age and from an important geographic area for understanding the phylogenetic diversification of Southern Hemisphere angiosperms and ecosystems. Collected fossils will be examined using standard physical techniques and microCT imaging. The study of these fossils will result in the description of new species and possibly higher taxa and provide a unique perspective into the floral diversity and composition of West Antarctica during the Cretaceous. In addition, the fossils will be placed within a phylogenetic framework, which will help to elucidate which lineages were diversifying in Antarctica.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.

第一部分：非技术描述流植物是当今地球上的主要土地植物群。他们在气候生活互动中起着重要的作用，并且是人类福祉（健康，食物，材料）的基础。尽管他们对我们的重要性，但他们的早期进化仍然神秘。没有这些植物如何发展的地质背景，我们将无法完全理解它们在确定气候和结构环境中的作用。这很重要，因为当今的陆地生态系统正在经历许多变化。化石记录表明，在白垩纪时期（145-66万年前）发生了与开花植物早期多样化有关的关键事件。从这个时期开始对化石花和水果的最新发现已经显着增进了我们对早期开花植物进化的理解。但是，这些发现中的大多数来自北半球，而南半球的类似发现相对缺乏。该项目将通过收集和描述来自西南极西部的白垩纪开花植物化石并将其放置在进化框架中，以更好地了解早期开花植物的进化，生物地理历史以及南极洲在现代生态系统形成中的作用。南极西部是南半球唯一的地方，据报道含有晚白垩纪晚期（100-66万年前）的三维花朵和水果。因此，对这些化石的恢复和研究可能意味着我们进一步理解开花植物进化的早期阶段。这项工作将导致对新物种的描述，这些物种将放置在进化分析和生物地理框架中，这将有助于阐明南半球开花植物的白垩纪多样化。这些化石将提供见解，使我们能够预测哪种植物可能会在变暖的南极和世界中繁衍生息。第二部分：技术描述，南半球开花植物的晚白垩纪多样化（血管）的一部分是由于有限量有限的良好含量良好的化石化石植物生殖结构。古植物研究表明，南极是开花植物白垩纪多样化的重要区域，是南半球唯一含有渗透性晚白垩纪晚期被子植物生殖结构的地方。拟议的研究将通过恢复和表征白垩纪晚被子植物，将它们置于系统发育环境中，并将其在北美和冈德瓦纳之间的生物地理联系中测试，从而阐明了南极在被子植物进化和现代生态系统中的作用和现代生态系统的组装。现场工作将在南极洲西部的詹姆斯·罗斯盆地进行，先前的报告和初步数据表明存在包括结构上保存的生殖结构在内的白垩纪晚期植物园的存在。这些化石的特殊保存使我们能够记录将其放置在可以确定其进化和生物地理环境的系统发育框架中必不可少的数据。詹姆斯·罗斯盆地内的分类学信息丰富且保存完好的被子植物生殖结构是一个关键时代，并且是从重要的地理领域，用于了解南半球被子植物和生态系统的物理多样化。将使用标准物理技术和MicroCT成像检查收集的化石。对这些化石的研究将导致对新物种的描述，并可能更高的分类单元，并在白垩纪期间对西南极洲西部的花卉多样性和组成的独特视角。此外，化石将被放置在系统发育框架内，这将有助于阐明哪些血统在南极洲多样化。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的影响审查标准通过评估来获得的支持。

项目成果

Extending beyond Gondwana: Cretaceous Cunoniaceae from western North America

延伸到冈瓦纳大陆之外：来自北美西部的白垩纪库尼亚科

• DOI: 10.1111/nph.17976
• 发表时间: 2022
• 期刊: New Phytologist
• 影响因子: 9.4
• 作者: Tang, Keana K.;Smith, Selena Y.;Atkinson, Brian A.
• 通讯作者: Atkinson, Brian A.

Winged Fruits of Friisifructus aligeri gen. et sp. nov. from the Late Cretaceous of Western North America

• DOI: 10.1086/724745
• 发表时间: 2023-05-01
• 期刊: INTERNATIONAL JOURNAL OF PLANT SCIENCES
• 影响因子: 2.3
• 作者: Tang，Keana K.;Smith，Selena Y.;Atkinson，Brian A.
• 通讯作者: Atkinson，Brian A.