Taphonomy and Paleoecological Significance of a Living Fossil: The Lingulid Brachiopod Glottidia palmeri

将研究一种活化石——舌状腕足动物Glottidia palmeri的地学和生态学。Lingulid腕足动物是寒武纪至近世近岸沉积物中常见且具有古生态学意义的化石。它们的出现通常被认为是浅水、盐度变化的环境。大量的舌鸟栖息在科罗拉多河三角洲的潮间带。这些种群提供了一个难得的机会来研究控制该物种的环境因素，壳中生长带的重要性，以及影响lingulid化石保存和古环境解释的死后过程。样本将沿着两条与海岸垂直的横断面采集：一条来自泥滩，另一条来自沙滩。这些数据将用于估计活种群与其壳体遗骸之间的对应关系，以及底物对形态和分类的影响。埋藏学分析揭示了埋藏学特征在多大程度上可以作为古环境指标。现场和实验室试验将评估在埋葬和运输过程中尸体变异的模式和速率。将通过监测个体生长和将带带模式与气象和潮汐记录相关联来评估壳中干扰环的环境意义。在舌鸟生长中记录的季节性或捕食模式在研究舌鸟化石时是有用的。这项研究将是第一次对这一常见和地质上有用的群体的代表的地学进行全面研究。我们的研究结果将影响现有的含舌岩的解释，并将大大提高这一长阶化石的古环境效用。

Flessa 9417054 The taphonomy and ecology of a living fossil, the lingulid brachiopod Glottidia palmeri, will be examined. Lingulid brachiopods are common and paleoecologically significant fossils in nearshore deposits ranging from the Cambrian to the Recent. Their occurrence is often taken to indicate shallow--water, variable salinity environments. Large populations of the lingulid Glottidia inhabit the intertidal flats of the Colorado River delta. These populations present a rare opportunity to examine the environmental factors controlling this species, the significance of growth--banding in the shell, and the post-mortem processes that affect the preservation and paleoenvironmental interpretation of lingulid fossils. Samples will be collected from along two shore-perpendicular transects: one from mudflats, the other from sandflats. These data will be used to estimate the correspondence between live populations and their shelly remains, and the effects of substrate on morphology and taphonomy. Taphonomic analysis will reveal the extent to which taphonomic features can be used as paleoenvironmental indicators. Field and laboratory experiments will assess the patterns and rates of post-mortem alteration during burial and transport. The environmental significance of disturbance--rings in the shells will be evaluated both by monitoring individual growth and through correlating banding patterns with meteorological and tidal records. Patterns of seasonality or predation recorded in lingulid growth--banding can prove useful in studies of fossil lingulids. This study will be the first comprehensive study of the taphonomy of a representative of this common and geologically useful group. Our results will affect existing interpretations of lingulid--bearing rocks and will greatly enhance the paleoenvironmental utility of fossils of this long-ranging order.