Paleoecologic gradient analysis of the Frasnian/Famennian extinction and recovery

该奖项是根据2009年《美国复苏和再投资法案》(公法111-5)资助的。Frasian/Famennian灭绝和恢复的古生态梯度分析安德鲁·M·布什和克里斯托夫·杜普拉斯康涅狄格州大学EAR-0922186 ABSTRACT在生命历史上，生物多样性多次被大规模灭绝所致，导致地球上大部分物种的灭绝。史前世界最大的五次大灭绝被称为“大五大灭绝”(恐龙在第五次也就是最近一次灭绝)，而今天人类造成的灭绝被称为“第六次大灭绝”。这种持续的灭绝，以及导致它的环境变化，将在未来几十年对生物群落产生重要影响--例如，随着气候变化以及竞争对手或捕食者的灭绝，物种的地理和生态范围可能会发生变化，导致新的群落由意想不到的物种组合组成。我们想要预测这些变化的性质？毕竟，这些群落为我们提供了栖息地和资源，物种的转移具有重要的经济后果。预测生物对物种灭绝和环境变化的反应的一种方法是研究过去对类似变化的反应--也就是研究化石记录中的大规模灭绝。物种灭绝只是产生了与以前的物种类似的“稀疏”群落，只是一些物种被移除了？或者，一旦捕食者和/或竞争者被消灭，物种是否会扩展到新的栖息地和生态位？也许变化的环境产生了由新的物种组合组成的群落。一些大规模灭绝可能太大和太灾难性，无法提供与现代世界相近的相似之处(例如，二叠纪-三叠纪的灭绝)；较不严重的灭绝，其中更大比例的物种存活提供了一个更直接的模型。晚泥盆世的大灭绝(特别是在弗拉斯尼亚-法门期交界处的事件)提供了一个合理的对比，该项目将对比大灭绝前后形成的化石组合。这些化石在纽约和宾夕法尼亚州收集，是生活在泥盆纪覆盖该地区的浅海中的群落的化石遗骸。PIS将结合生态梯度分析和沉积学分析，记录每个物种在灭绝之前和之后生活的环境，以及随时间发生的任何变化。他们还将检查物种间同现模式的任何变化。这一结果不仅将揭示泥盆纪的生物变化，而且有望揭示下个世纪的生物变化。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Paleoecologic gradient analysis of the Frasnian/Famennian extinction and recoveryAndrew M. Bush and Christophe DuprazUniversity of ConnecticutEAR - 0922186ABSTRACT A number of times during life's history, biodiversity was decimated by mass extinctions that wiped out a large proportion of the Earth's species. The five largest mass extinctions of the prehistoric world are known as the "Big Five" (the dinosaurs died out in the fifth and most recent), and the present-day, human-induced extinction has been called the "Sixth Extinction". This ongoing extinction, along with the environmental changes that are causing it, will have important effects on biological communities in the coming decades?for example, as the climate changes and as competitors or predators go extinct, species' geographic and ecological ranges may shift, leading to new communities composed of unexpected combinations of species. We would like to predict the nature of these changes?after all, these communities provide us with habitat and resources, and the shifting of species has important economic consequences. One way to forecast biotic responses to extinction and environmental change is to study past responses to similar changes?that is, to study mass extinctions in the fossil record. Did extinctions simply produce "thinned out" communities that were similar to previous ones, merely with some species removed? Or did species expand into new habitats and ecological niches once predators and/or competitors were eliminated? Perhaps a changing environment produced communities composed of novel combinations of species.Some mass extinctions were probably too large and catastrophic to provide close analogues to the modern world (e.g., the Permian-Triassic extinction); a less severe extinction in which a greater proportion of species survived provides a more direct model. The Late Devonian extinction (specifically, the event at the Frasnian-Famennian boundary) provides a reasonable comparison, and this project will contrast fossil assemblages that formed before and after the extinction. Collected in New York and Pennsylvania, these assemblages are the fossilized remains of communities that lived in a shallow sea that covered the area in the Devonian. PIs will combine ecological gradient analysis with a sedimentological analysis to document the environments in which each species lived before and after the extinction, and any changes through time. They will also examine any changes in co-occurrence patterns among species. The results will cast light not just on biotic changes in the Devonian, but also, hopefully, on those in the coming century.