Invertebrate Functional Diversity of Fossils From Arrow Canyon, Nevada

Paleontology can be used to study how ecosystems evolve and respond to changes in the environment. Here we examine invertebrate fossils from the Pennsylvanian, a time period that ranged from 323.2 to 298.9 million years ago, which are preserved along the walls of Arrow Canyon (Nevada) in the Bird Spring Formation. We surveyed three sites within the canyon, and used data from the Paleobiology Database to create a list of taxa found on the canyon from this time interval. Although ecosystems have traditionally been studied using the composition of the ecosystem (the number of species), recent work has shown that functional structure may be more important to the health of an ecosystem. Therefore, here we examine functional diversity (the types of functions performed by all of the organisms in an ecosystem). Three functional traits were assigned to each taxon: tiering, feeding, and motility, using the Paleobiology Database and the scientific literature. We examined both how much of the functional space was filled, and how species were distributed within functional space using Functional Entities, unique combinations of functional traits. Brachiopods dominated the fossil samples, as the geologic setting favored the preservation of their shells. Other invertebrate phyla are represented, though their sample sizes are low. Further study on the functional diversity of the Bird Spring Formation may incorporate fossil data from other fossil localities to expand sample sizes at the genus level.