RUI: Pattern of Extinction and Replacement at the Lower- Middle Cambrian Boundary Event in the Great Basin, Western U.S.

灭绝可能是所有物种的最终命运，地质学家、生物学家甚至立法者（如《濒危物种法》）一直对这个问题特别感兴趣。灭绝事件是指许多物种在地质学上的短时间内灭绝，对地球科学家和进化生物学家来说一直具有历史意义，因为它们被方便地用来划分地质时间。在这个项目中，PI和学生们将详细研究最早的灭绝事件之一，在中下寒武纪边界，并帮助回答诸如事件到底有多突然，动物群灭绝的百分比，以及物种是否在灭绝之前就开始数量下降等问题。这些早期分类群生活的古环境也将从现在埋葬它们的岩石类型中重建出来。

Extinction, which may be the ultimate fate of all species, has always held a special interest for geologists and biologists, and even legislators (e.g., Endangered Species Act). Extinction events, when a number of species become extinct over a geologically short period time, have always had historical significance to Earth scientists and evolutionary biologists, as they are conveniently used to divide up geologic time. In this project, PI and students will examine in detail one of the earliest extinction events, at the Lower-Middle Cambrian boundary, and help answer questions such as how sudden the event really was, what percentage of the fauna went extinct, and whether species began to decline in numbers prior to their extinction. The paleoenvironment in which these early taxa lived will also be reconstructed from the type of rock that now entombs them.