Collaborative Research: Comparative Taphonomy and Time-Averaging of Mollusk-Echinoid Assemblages using High-Performance Radiocarbon Dating System

合作研究：使用高性能放射性碳测年系统对软体动物-海胆组合进行比较埋藏学和时间平均

• 批准号: 2127644
• 负责人: Darrell Kaufman
• 金额: $ 16.61万
• 依托单位: Northern Arizona University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2127644&HistoricalAwards=false
• 关键词: Collaborative; Research; Comparative; Taphonomy; Time

The goal of this project is to assess what happens after death with remains of shelly animals (mollusks and sea urchins) that dominate many seafloors today and are widespread in the marine fossil record. Do those shells last for millennia or perish quickly? Because shells of mollusks and tests of sea urchins are abundant in many marine habitats, how fast or slow they perish may affect the carbon cycle, affect sediments in marine habitats, influence how sedimentary rocks form, and impact the resolution and quality of the fossil record. Moreover, there is tentative evidence that mollusks and sea urchins may differ dramatically in shell durability. Mollusk shells probably persist for centuries around the seafloor, whereas sea urchin tests only survive months or possibly years. This project will compare the post-mortem fate of mollusk shells and sea urchin tests and associated predictions across various types of marine habitats. By combining field surveys of live and dead animals and radiocarbon dating of dead remains, the project will quantify the survival time of mollusk and echinoid remains and use field data to test predictions based on expected shell destruction rates. The results will advance our understanding of marine sedimentation processes, formation of the sedimentary rock and fossil records, possible biases due to variable preservation of different animal groups, and the temporal resolution of fossil samples. The project will provide a direct opportunity for testing a new advanced strategy of radiocarbon dating with a real potential to advance our general ability to date fossil samples quickly and efficiently. The project will also serve as a platform for training a new generation of scientists and broadening participation of groups underrepresented in biology and geology. In addition, educational movies using novel immersive digital technology will be used to convey the excitement of conducting scientific research in marine settings. The project will engender international partnerships with the Commonwealth of Bahamas and provide collaborative bridges connecting students and researchers from public universities in Arizona and Florida.This project aims to improve our understanding fossilization processes that lead to preservation or destruction of benthic mollusks and echinoids, which are both important components of the marine fossil record. The main goal is to assess the hypothesis that these two groups of animals differ in skeletal durability and fossilization potential. By integrating live-dead field surveys and new generation radiocarbon instrumentation, we will test three predictions that stem from this hypothesis: (1) time-averaging, variation in age of specimens, is orders of magnitude higher for mollusks compared to echinoids; (2) live-dead specimen ratios are orders of magnitude lower for mollusks than for echinoids; and (3) specimen-fragment ratio is significantly higher for mollusks than for echinoids. These predictions will be tested using surface and subsurface samples from present-day seafloors around Florida and the Bahamas. The project will target diverse carbonate and siliciclastic settings to assess if the observed patterns are generalizable across different habitat types. The project will produce 45 live-dead surveys of mollusks and echinoids at 15 sampling sites across five localities. These field data will be augmented by radiocarbon dating of 1000 individual specimens of mollusks and echinoids. This extraordinarily large number of radiocarbon ages is now feasible using the new NSF-supported MICADAS accelerator mass spectrometer (AMS) at Northern Arizona University (NAU) . Quantifying taphonomic differences between two major groups of marine invertebrates will advance our understanding of sedimentological processes related to formation of biogenic sedimentary rocks, the role of shell-producing organisms as carbon sinks or carbon sources, and the quality and temporal resolution of paleontological data. The proposed approach is designed as a broadly applicable research strategy transferrable to study systems. In terms of broader impacts activities, the project will advance STEM careers of one postdoctoral researcher, one graduate student, and ~12 undergraduate students, with specific focus on recruitment and career development of minority STEM students. The student training will encompass comprehensive research skills and will be vertically integrated to benefit mentoring skills of early career scientists. Outreach and education materials using 360° immersive video technology will include 3D-augmented reality movies of seafloor exploration by SCUBA (freely accessible as immersive 3D YouTube movies). The partnership between UF and NAU will facilitate networking of minority students in Florida and Arizona, and the international field work in partnership with the Gerace Research Centre will engage Bahamian students.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.

该项目的目标是评估当今许多海底并广泛存在于海洋化石记录中的贝壳动物（软体动物和海胆）的遗骸在死亡后会发生什么。软体动物和海胆在许多海洋栖息地中大量存在，它们死亡的快慢可能会影响碳循环，影响海洋栖息地的沉积物，影响沉积岩的形成方式，并影响分辨率和质量此外，有初步证据表明，软体动物和海胆的外壳耐久性可能存在显着差异，而软体动物的外壳可能会在海底存活数个世纪，而海胆的测试只能存活数月甚至数年。 -软体动物贝壳和海胆的尸检命运测试以及各种类型海洋栖息地的相关预测通过结合对活体和死亡动物的实地调查以及对死亡遗骸的放射性碳测年，该项目将量化海胆的生存时间。软体动物和海胆遗骸，并使用现场数据来测试基于预期贝壳破坏率的预测，结果将增进我们对海洋沉积过程、沉积岩和化石记录的形成、由于不同动物群体的不同保存而可能产生的偏差的理解。该项目将为测试新的先进的放射性碳测年策略提供直接机会，具有真正提高我们快速有效地测定化石样本的能力的机会。该项目还将作为培训平台。新一代科学家和拓宽此外，利用新颖的沉浸式数字技术的教育电影将用于传达在海洋环境中进行研究的兴奋感，该科学项目将与巴哈马联邦建立国际伙伴关系，并提供合作桥梁。来自亚利桑那州和佛罗里达州公立大学的学生和研究人员。该项目旨在提高我们对导致底栖软体动物和海胆类动物保存或破坏的化石化过程的了解，这两种动物都是海洋化石记录的重要组成部分。这两类动物在骨骼耐久性和化石潜力方面存在差异的假设通过整合活死现场调查和新一代放射性碳仪器，我们将测试源于该假设的三个预测：（1）时间平均、年龄变化。与海胆相比，软体动物的标本数量级高；(2) 软体动物的活死标本比比海胆低几个数量级；软体动物的预测值明显高于海胆类动物。该项目将针对不同的碳酸盐和硅质碎屑环境，评估观察到的模式是否适用于不同的栖息地类型。该项目将在五个地区的 15 个采样点对软体动物和海胆进行 45 次活死调查，这些现场数据将通过放射性碳测年得到补充。现在，使用北亚利桑那大学 (NAU) 的 NSF 支持的新型 MICADAS 加速器质谱仪 (AMS)，可以对 1000 个软体动物和海胆个体样本进行量化，从而量化两个主要海洋无脊椎动物群体之间的埋藏学差异。我们对与生物沉积岩的形成、产壳生物作为碳汇或碳源的作用以及所提出的方法被设计为一种广泛适用的研究策略，可转移到研究系统中。就更广泛的影响活动而言，该项目将促进一名博士后研究员、一名研究生和约 12 名本科生的 STEM 职业生涯。学生，特别关注少数民族 STEM 学生的招生和职业发展，学生培训将包括综合研究技能，并将垂直整合，以利于早期职业科学家的指导技能，并包括使用 360° 沉浸式视频技术的教育材料。 SCUBA 海底探索的 3D 增强现实电影（可作为沉浸式 3D YouTube 电影免费观看） 佛罗里达大学和 NAU 之间的合作将促进佛罗里达州和亚利桑那州的少数族裔学生的网络交流，以及与 Gerace 研究中心合作的国际实地工作。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。