Determining the Direction of Environmental Trilobite Migration
Walker Weyland ’21, McHenry, Illinois
Majors: Geology; Biology
Minor: Studio Art
Trilobites fossils first appear in the Early Cambrian (~520 million years ago) and subsequently become a crucial part of ocean ecosystems for a nearly 270 million year time interval. Their abundance and complexity, as well as the existence of modern analogous organisms such as isopods, have made them popular as subjects of study. This study tracked the deepwater adaptations of early trilobites to investigate the relationship between morphology and environment, and to test if early trilobites evolved in deepwater settings before emigrating to shallow environments. It was found that modern assumptions of the morphological differences between shallow and deep water arthropods do not hold true in the Early Cambrian. A possible explanation for this is that the modern ecosystems which generate these depth-related relationships were not yet present. In future studies, the addition of more species and a longer time frame of analysis will be needed to conclusively determine the direction of early trilobite environmental migrations.