RUI: Analysis of an Early-Middle Devonian Ecosystem: Trout Valley Formation, Maine

早-中泥盆世生态系统的分析：Trout Brook，MaineRobert Gastaldo和Robert E。缅因州的鳟鱼谷地层保存了为数不多的早中泥盆世（埃姆斯-艾菲利斯）时期的陆地生态系统之一。 它被用作早期陆地群落结构的初步模型，其中机会主义植物的马赛克占据了景观。 这些植物被认为是克隆的，主要是因为这些植物的有性繁殖被认为是相对罕见的（基于营养和孢子囊植物之间的比例）。 在这个植被镶嵌，植物和动物之间的相互作用仅限于碎屑喂养，推断从动物形态，粪化石分布，植物损害的性质。 这种景观的解释是基于很少公布的现场数据，其中的环境背景和沉积背景已被解释为半咸水三角洲设置。 似乎没有证据支持这种环境背景，也没有埋藏学数据支持生态重建。 拟议的研究将由地质学本科专业作为高级独立项目进行，包括实地和实验室研究。 本科生将测试四个假设，重点是：（1）鳟鱼谷形成的地层序列;（2）植物化石组合的埋藏特征;（3）相关的陆地大型无脊椎动物和早期生态系统结构;（4）可能记录在这些组合中的植物-动物相互作用。 学生将开发一个环境框架，其中化石组合可以放置在更准确地了解其成因;限制露头带内组合的植物和动物埋藏特征，从中可以产生更现实的古环境重建;并调查早中泥盆世记录的植物-动物相互作用的进化水平。

RUI: Analysis of an Early-Middle Devonian Ecosystem: Trout Brook, MaineRobert Gastaldo and Robert E. NelsonEar-0087433The Trout Valley Formation, Maine, preserves one of the few terrestrial ecosystems of the Early to Middle Devonian (Emsian-Eifelian) age. It has been used as the prima facie model of early terrestrial community structure in which a mosaic of opportunist plants populated the landscape. It is thought that these plants were clonal mainly because sexual reproduction in these plants is thought to be relatively rare (based upon the ration between vegetative and sporangium-bearing plants). Within this vegetational mosaic, interactions between plants and animals was restricted to detritus feeding, as deduced from animal morphologies, coprolite distribution, and the nature of plant damage. The interpretation of this landscape is based upon scant published field data, of which the environmental context and depositional setting has been interpreted previously as a brackish delta setting. There appears to be little evidence to support this environmental context, and there are no taphonomic data to support the ecological reconstruction. The proposed research will be conducted by undergraduate majors in Geology as senior independent projects that include both field and laboratory studies. Undergraduates will test four hypotheses focusing on: (1) the stratigraphic sequence of the Trout Valley Formation: (2) the taphonomic signature of plant fossil assemblages; (3) the associated terrestrial macroinvertebrates and early ecosystem structure; and (4) the plant-animal interactions that may be recorded in these assemblages. Students will develop an environmental framework in which the fossil assemblages can be placed for a more accurate understanding of their genesis; constrain the plant and animal taphonomic signatures of the assemblages within the outcrop belt from which a more realistic paleoenvironmental reconstruction can be produced; and investigate the evolutionary level of plant-animal interactions recorded in the Early-Middle Devonian.