Environmental and Taxonomic Control of Growth, Morphology, Taphonomy, and Sediment Production in Living Stalked Crinoids (Echinodermata)

活茎海百合（棘皮动物）生长、形态、埋藏学和沉积物产生的环境和分类控制

• 批准号: 9628215
• 负责人: Charles Messing
• 金额: $ 4.98万
• 依托单位: Nova Southeastern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-15 至 1999-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9628215&HistoricalAwards=false
• 关键词: Environmental; Taxonomic; Control; Growth; Morphology

9628215 Messing Stalked crinoids represent a major component of living assemblages and contribute substantially to modern skeletal sediments along the western flank of the Little Bahama Bank. Three aspects of stalked crinoid biology and taphonomy are examined in order to better understand the processes and rates of production, and post-mortem modifications of modern crinoidal sediments, as follows: 1) How do growth rates among different species and within species vary at different depths and under different environmental conditions? Growth rates are measured directly via proven methods of tagging and recovery that permit in situ maintenance of specimens. 2) To what extent do depth and environmental conditions control crinoid morphology? Many features currently applied to crinoid species diagnoses and phylogenetic hypotheses vary ontogenetically, ecophenotypically, geographically and/or bathymetrically. Clear understanding and recognition of crinoid species are critical to biostratigraphic analyses and paleoecological reconstruction and hypothesis-testing. Application of previously successful tag-and-recovery experiments will permit specimens to be transplanted to different habitats and depths. 3) How do morphological and ecological variations among and within taxa affect taphonomic processes such as patterns of stalk disarticulation, skeletal sediment production rates, and the nature of skeletal grains contributed to sediments, and how can this information be applied to reconstruction of fossil assemblages? A combination of anatomic and petrographic thin sections and scanning electron microscopy of living and experimentally decomposed crinoid stalks, and skeletal grains retrieved from sediments are used to examine ligament anatomy, the pattern of ligament decay and the development of cements relative to increasing stalk degradation. The study organisms have a fossil record dating to the Triassic. As such, these modern assemblages represent an excellent analogue for better understan ding paleoecological processes and interpreting ancient crinoidal deposits. The aspects of crinoid ecology and taphonomy proposed for study are thoroughly interconnected and represent a logical extension of the successful research program carried out under prior NSF funding at previously established study sites.

小行星9628215 柄海百合是生活组合的主要组成部分，并大大有助于现代骨骼沉积物沿着西翼的小巴哈马银行。 为了更好地了解现代海百合沉积物的生产过程和生产率以及死后的变化，对有柄海百合生物学和埋藏学的三个方面进行了研究，如下：1）不同物种之间和物种内的生长率在不同深度和不同环境条件下如何变化？ 生长速率是直接测量通过成熟的方法标记和恢复，允许在原位维护标本。 2)深度和环境条件在多大程度上控制海百合的形态？ 目前应用于海百合物种诊断和系统发育假说的许多功能在个体发育、生态表型、地理和/或水深上各不相同。 明确海百合的种类是进行生物地层学分析、古生态重建和假说验证的关键。 应用以前成功的标记和回收实验将允许标本移植到不同的栖息地和深度。 3)分类群之间和内部的形态和生态变化如何影响埋藏学过程，如柄断节模式、骨骼沉积物产生率和沉积物中骨骼颗粒的性质，以及这些信息如何应用于化石组合的重建？ 解剖和岩相学薄切片和扫描电子显微镜的生活和实验分解海百合茎，和骨骼颗粒从沉积物中检索的组合被用来检查韧带解剖，韧带腐烂的模式和水泥的发展相对于增加秸秆降解。 研究生物的化石记录可以追溯到三叠纪。 因此，这些现代组合代表了一个很好的模拟，更好地理解古生态过程和解释古代海百合沉积。 建议进行研究的海百合生态学和埋藏学方面是完全相互关联的，并且代表了在先前建立的研究地点在NSF资助下进行的成功研究计划的逻辑延伸。