THE DEATH ASSEMBLAGE OF YELLOWSTONE NATIONAL PARK: A LIVE-DEAD ANALYSIS OF A TEMPERATE MAMMALIAN COMMUNITY

Although actualistic taphonomic studies of large-bodied mammalian death assemblages have been largely limited to African localities, expansion of such studies into a variety of climates and mammal communities is vital for understanding the ecological data captured within paleontological assemblages from climates without analogues in modern-day Africa. Examining the fidelity of mammalian death assemblages to record the living ecology's species richness, age and body-size distributions, and habitat preferences is paramount to understanding how accurately a fossil deposit can reflect the ecological composition of the paleocommunity. A preliminary live-dead comparison of the ungulate community of Yellowstone National Park, WY, provides a baseline to assess the ecological fidelity of a temperate large-mammal death assemblage. Rates of skeletal disarticulation and bone decomposition in Yellowstone are generally lower than those documented in previous live-dead studies. Furthermore, the recent reintroduction of wolves into the Yellowstone ecosystem following a local extinction provides an opportunity to study carcass utilization in relation to prey availability. Expansion of actualistic taphonomic studies to encompass a variety of climates and ecologies is vital for understanding the ecological and evolutionary histories of modern mammal groups. Only by studying the taphonomic pressures inherent to a wide variety of modern climates and ecologies can we begin to understand the paleoecological significance of paleontological finds. Modern live-dead comparisons enable us to examine the ecological fidelity of a death assemblage and offer a guide to the kinds of paleoecological conclusions that can be appropriately drawn from the fossil record. In particular, examining death assemblages derived from temperate mammalian communities such as the Yellowstone ecosystem provides insight into the taphonomic pressures of Pleistocene mammal assemblages and permits more accurate paleoecological conclusions from such fossils deposits.