Herbivory exerts a profound influence on ecosystem function and physiognomy.� How a plant community responds to grazing by domestic herbivores is to a large degree dependent on its evolutionary history of herbivory.� Plants evolving in communities with a long evolutionary history generally possess adaptations that make them resilient to grazing, whereas plants evolving in communities without such history often do not.� The evolutionary history of herbivory therefore can serve as an indicator of a system�s resiliency to grazing.� However, determining a system�s evolutionary history of herbivory is problematic because quantitative measures are needed of native herbivores over an evolutionary time period, as is knowledge of plant origin and evolution.� Paleoecology provides a useful framework for assessing the co-evolution of plants and herbivores.� The Patagonian steppe of South America is a biotic province with an evolutionary history of herbivory whose resilience to grazing is uncertain.� Herbivory on the steppe transitioned from a diverse assemblage of megaherbivores during much of the Tertiary to an impoverished community consisting of a single, large herbivore�the guanaco (Lama guanicoe)�from the late Pleistocene extinction onward.� Here we present a paleoecological approach to reconstruct the evolutionary history of herbivory in Patagonian steppe and examine the role of megaherbivores and guanaco in shaping its vegetation.� We discuss how present management is misaligned with the steppe�s evolutionary history of herbivory and offer suggestions for steppe conservation under contemporary land use.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.