Successful conservation and restoration efforts require an understanding of the drivers of ecosystem dynamics. Often, conservationists seek to return highly altered landscapes to a “pristine” state that may or may not have existed in the past and is often poorly understood. With increased human impact, this typically requires intensive management under disturbance regimes that are quite different than those of the past. Understanding the role of megaherbivores in ecosystem dynamics is particularly challenging, because in many cases key species are long absent from the landscape. In response, some have suggested reintroducing locally extinct species or their closest analogs to extirpated groups. Large mammals are particularly susceptible to extinction, and the megafauna has experienced disproportionate species losses since the last ice age. What impact did local and global megaherbivore extirpation have on the evolution of landscapes during the early Holocene? Would changes in modern herbivore biodiversity have a similar impact on vegetation? How would such changes influence local fire regime, soil properties, or other factors that could contribute to ecological cascades?

Recent publications on herbivore-plant dynamics, particularly long-term exclusion studies, indicate the importance of megafauna to the maintenance of many natural habitats. Megaherbivores often play a keystone role in modern ecosystems, which conservationists must consider if they are to implement a systems-based approach. One proposed strategy, “re-wilding,” involves reintroducing herbivores to regions where now-extinct species once lived. Research assessing the effectiveness of such strategies should include both modern and paleoecological perspectives. Paleoecological data can offer spatial and temporal perspectives not possible with modern process studies, and can address the rate and extent of landscape change following a particularly dramatic example of selective extinction during the late Pleistocene. Paleoenvironmental proxies allow reconstruction of megafaunal presence and ancient fire regimes, and advances in stable isotope analysis allow reconstruction of diet and migratory patterns of extinct species. Better integration of modern landscape ecology and paleoecology offers significant contributions to future restoration efforts. Modern ecologists can offer direct experimental and observational evidence of the impacts of herbivore presence on the landscape; paleoecologists can contribute a broader spatiotemporal perspective. Whether or not megaherbivores will ultimately play a role in restoration efforts, an understanding of their impact and ecology is critical to the development of conservation strategies.