Scientific evidence suggests that economic activity is threatening global biodiversity in ways that could severely degrade nature's flow of ecosystem services. Yet, there is relatively little work in economics that addresses biodiversity loss. Some economists have called for better integration of economic and ecological models to address biodiversity and the attendant ecosystem services. Current integrated approaches in economics are discussed, and they take in ecosystem services, ecosystem externalities, and substantial ecological modeling. Much of the modeling uses Lotka-Volterra equations, which are standard in ecology, although there is concern that the equations lack the microfoundations of plant and animal behavior. An alternative approach is to admit microbehavior using economic optimization techniques that build adaptive ecological systems. However, much more effort is needed to assess whether admitting more ecological detail into economic models will be fruitful.