Thursday, August 5, 2010: 1:30 PM-5:00 PM
303-304, David L Lawrence Convention Center
Tania N. Kim
An important recent advance in ecology has been the renaissance of macroecology. Most macroecological research, however, is non-experimental and remains focused on pattern. At the same time, those studies that have used the tools of experimental community ecology to address questions at geographic scales have found this to be a highly productive approach. The necessity of understanding how and why species interactions vary across broad spatial gradients is highlighted by global threats to biodiversity and the current rate of species loss. We propose a session that integrates descriptive approaches to documenting latitudinal patterns with experimental approaches focused on underlying mechanisms. This organized oral session brings together the research of both senior and upcoming researchers who are using novel approaches (null modeling, phylogenetics, experimental community ecology) to explore the causes and consequences of broad geographic patterns in species interactions. In this session, we will provide a venue for upcoming and established scientists to present the more recent theoretical and empirical advances in attempts to link pattern process in consumer-resource interactions across large geographic ranges. We will first begin by providing a synthetic overview on the origin and maintenance of latitudinal gradients in species interactions, focusing on examples from marine intertidal habitat. Next, we will focus on patterns of trophic interactions driven by both bottom-up and top-down sources of variation. Although researchers in the field generally agree that both forces are in play in any given context – the ways in which they interact at large scales is a current source of debate. This part of the session will provide an opportunity to assess the generality of latitudinal patterns in these relationships. The second part of the session will focus on evolutionary perspectives. Geographic sources of variation are an important component of attempting to understand how species interactions such as coevolutionary arms races or life history changes spurred by inter- and intra-specific competition play out. We will provide examples of genetically-based clines in prey defenses as mechanisms for variability in consumer-prey interactions. The session will conclude with talks that link to the broader conference theme of climate change. We will focus on research that integrates evolutionary and ecological perspectives on maintaining diversity gradients and on the mechanisms underpinning population responses to climate induced range expansion. Together, these talks will synthesize food web, evolutionary, and climate-related perspectives to explore the causes and consequences of latitudinal gradients in species interactions.