A student field assistant maps an elk carcass in Yellowstone National Park

Bones laying on landscapes offer glimpses into previous generations of wildlife. These ghosts of past populations provide valuable information for understanding, conserving, and managing modern ecosystems.

My research in Yellowstone National Park established that temperate large mammal (ungulate) bone accumulations on landscape surfaces can faithfully record their source community’s richness and proportional abundance structure. Paired with recent surveys of living populations, bone accumulations also correctly identify species that have significantly changed in abundance over the last ten to eighty years, and the directions of those shifts (including local invasions and extirpations; Miller 2011, Behrensmeyer and Miller 2012). Because the season of death/input for some skeletal elements are identifiable (shed elk antlers are dropped in late-winter; bones of newborns are introduced in the spring), bone accumulations can be used to demarcate the spatial distribution of critical habitats (wintering and calving grounds) across a population’s geographic range (Miller 2012). Furthermore, bones decompose along stereotypical stages, allowing cohorts of input to be identified within a bone accumulation; these cohorts also track changes in species richness, relative abundances, and landscape use across decades-to-centuries (Miller 2011, 2012, Miller et al. 2013, 2014).