PRESERVATIONAL QUALITY AND ITS IMPACT ON DIVERSITY METRICS

The preservational quality of fossil organisms—i.e. whether preserved as original mineralogy or molds, whole skeletons vs. fragments—can vary greatly from assemblage to assemblage, outcrop to outcrop, and time-interval to time-interval. This variability in preservational quality and its effects on observed paleoecological patterns in the fossil record, however, is an often neglected aspect of many paleontological studies. One reason for this may be that the degree to which quality of preservation is capable of altering community level paleoecological data is relatively poorly understood. In order to address this problem a series of computer simulations have been developed to examine the effects of differential preservation on various community level paleoecological diversity metrics, including richness, Shannon’s H, evenness (E, J, PIE, Ess), and rank order. Here the results of these simulations, as well as potential implications for observed patterns in the fossil record will be presented. Preliminary results indicate that identically structured communities (identical richness, H, and evenness) can take on very different appearances once preserved, and that it is the behavior of the most common taxa which drive these differences.