Experimental studies of food webs: Causes and consequences of trophic interactions

This chapter reviews some of what we have learned from experimental studies of food webs conducted in an assortment of natural and constructed systems. The main themes are the roles of energy and other factors in determining food chain properties, the consequences of omnivory for the dynamics of omnivores and their prey, and the impacts of food web complexity on population andcommunity dynamics. Throughout, I emphasize the important interplay between the roles of theory and experiment in advancing our knowledge of community ecology. I also describe other key phenomena that remain poorly integrated in food web theory and that also require much additional experimental work. These areas include the development of inclusive frameworks for ecological networks that incorporate nontrophic interactions, such as some mutualisms, and the incorporation of evolutionary dynamics in the consideration of food web architecture.