International Research Fellowship Program: Trait-mediated Indirect Interactions: Effects in Community Assembly, Species Loss, Spatial Structure and Diversity-Stability Relationsh

Golubski Antonio J, Chicago IL

Investigators

Abstract

0754419 Golubski The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twenty-four month research fellowship by Dr. Antonio J. Golubski to work with Dr. Peter A. Abrams at the University of Toronto in Canada. In ecological communities, both direct and indirect interactions between two species are often modified by additional species. These are known as interaction modifications or trait-mediated indirect interactions (TMIIs). Such interactions have gained much attention in the recent ecological literature, but most theoretical models that include them have focused on small communities and specific scenarios. The general implications of TMIIs, and of the various ways of incorporating them into existing theoretical frameworks, remain unclear. The current research seeks to build a more general understanding of the implications of TMIIs in large communities. Existing models and theoretical frameworks are being modified to include TMIIs and explore their implications for community assembly, diversity/stability relationships, community response to species loss, and endogenously generated spatial structure. This is being done using various combinations of assumptions concerning the distributions of TMII strengths, the relationships between these strengths and the strengths of the direct effects they modify, the relationship between a species' distance (in terms of number of nodes) from a direct interaction and the probability and/or strength with which it modifies that interaction, and the interaction between TMIIs when multiple species modify the same direct effect. The effects of incorporating TMIIs under different scenarios, such as when direct interactions are constrained to be purely trophic (i.e. food webs) or purely competitive, or when the TMIIs represent specific biological phenomena such as defensive behavior in prey or adaptive foraging by predators, are also being compared. Ultimately, datasets from real ecological systems will be sought out in order to look for patterns consistent with the most interesting and important effects of TMIIs found by the theoretical work. The project's goal is to develop a general picture of when TMIIs might be expected to be most important in communities and what generalities, if any, might be made about their effects.