ECOLOGICAL-EVOLUTIONARY EVENTS

Following earlier work in low-oxygen macrofossil biofacies of Cretaceous black shales, I investigated diversity and equitability trends among Western Interior benthic assemblages and proposed some ideas about the relationship between low oxygen-adapted taxa and evolutionary change (see Palaios, v. 12, p. 449; see also Fig. 3). More recently, I collaborated with NU undergraduates on a test of the coordinated stasis hypothesis in Western Interior Cretaceous faunal assemblages using biostratigraphic range data collated by my Ph.D. advisor, Erle Kauffman, and a group of his students (Kauffman et al., 1993). Finally, I put together a research group (including Dr. C. Brett, Dr. D. Hollander, Dr. T Lyons, Dr. A. Murphy, Dr. C. Ver Straeten) to investigate the correlation between geochemical records of paleoenvironmental change that occurred in association with the Late Devonian faunal turnovers upon which the coordinated stasis hypothesis was originally defined (Fig. 4). Our goal has been to contribute to understanding the causes of the faunal turnover events preceding the Frasian-Famennian mass extinction, and if possible, shed some light on that event as well. This work has been a component of the Ph.D. theses of Adam Murphy and Josef Werne and the results are summarized in recently published and submitted papers (see Bibliography).