Late Pleistocene megafauna extinction leads to missing pieces of ecological space in a North American mammal community

Populations of large-bodied mammals are declining at an alarming rate. Their decline has serious ecosystem consequences because they have important functional roles that are not replicated by smaller-bodied animals. Understanding how their decline or potential extinction will influence ecosystem processes is critically important and time-sensitive. Here, we use the paleorecord as an analogy for modern biodiversity loss. We examine consequences of the terminal-Pleistocene megafauna extinction on a mammal community from the Edwards Plateau, Texas by characterizing changes in animal body size and dietary isotopic niche before and after the event. We find significant reorganization of the community, particularly among carnivores, a loss of ecological complexity, and many vacant niches. The loss of complexity likely meant a reduction in ecosystem resilience.