PARENT SESSION
Thursday, August 10, 1:30-5:00 pm
OOS 14 - Ecological stoichiometry of terrestrial animals
Ballroom D, Ballroom Level, Cook Convention Center
Organized by: AD Kay (adkay@stthomas.edu), S Bertram, and J Schade

This session will examine the degree, causes, and ecological consequences of differences in elemental composition among terrestrial animals.

Stoichiometry and food web ecology: what are the questions and how do we answer them?

Schmitz, Oswald^*,1, ¹ Yale University, New Haven, CT

ABSTRACT- Syntheses of trophic interactions among food webs are generally guided by three key questions: (1) Why are there differences in the strength of top-down control among systems (particularly between terrestrial and aquatic systems)? (2) Why is the distribution of trophic interaction strengths log-normally distributed, viz. why are food webs dominated by weakly interacting species? (3) Who are the strongly vs. weakly interacting species, and why are they so? It is difficult to derive concrete answers to these questions because current syntheses must rely on data from disparate studies that were not explicitly designed to answer the key questions. I hope to spur-on ecology broadly, and terrestrial ecology specifically, to undertake a systematic, concerted effort to understand the mechanisms that provide answers to the three questions. I show how and why a stoichiometric perspective can provide the underlying framework for deriving answers. Using insights from my own research, I will develop a set of working hypotheses that begin to provide answers to the three questions and outline the kind of experimental research that must be undertaken to advance our understanding of the functional basis for differences in trophic interaction strengths among systems and the pattern of interaction strengths among species within systems.

Key words: trophic interactions, C:N stoichiometry, hypotheses and research