INTRODUCTION

No organismal group has contributed more to the origin and development of global change research than foraminifera. Foraminiferal biostratigraphical data provide many of the finest subdivisions on the clockface of geologic time. As such, foraminiferal faunas are routinely used to provide temporal control for global change research in the last 250 Ma of Earth history. Foraminiferal biogeography has also been important in the documentation of tectonic plate geometries and in the reconstruction of palaeoceanographic circulation patterns, both of which play decisive roles in controlling the distribution of climatic belts. In addition, stable isotopic analyses of foraminiferal tests (= shells) have been extensively used as palaeothermometers and palaeoproductivity indicators.

While these types of foraminiferal data have been employed (along with other independent lines of evidence) to identify, characterize, and date global change events, patterns of foraminiferal diversification have also clearly been affected by these events. Cretaceous through Recent genus-richness data for this group (Tappan & Loeblich, 1988) show maxima in the Albian–Cenomanian, Campanian–Maastrichtian, Mid Eocene, and Miocene, with minima occurring in the Early Paleocene, Oligocene, and Pliocene for both benthic and planktonic forms (Fig. 5.1).