Mathematical Biology Seminar

Sharon Bewick
3:05PM, Wednesday, November 10, 2010
LCB 225
When Climate and Trade-offs Interact: Sensitivity of ant assemblages to climate change

Abstract: When predicting the sensitivity of ant assemblages to climatic change, it may be important to consider trade-offs that both currently allow coexistence between ant species in a community and also are likely to change under warming regimes. In particular, differences in thermal tolerance will likely play a key role in determining ant community composition under conditions of climatic warming, and a dominance thermal-tolerance relationship has been proposed in several systems. In order to mathematically interpret and predict shifts in ant species abundance that might occur as a result of climate change, I take the basic assumption of linear transitive dominance hierarchies from a mathematical dominance-discovery model proposed in (Adler et. al., 2007), and then extend the model by including terms to describe species specific seasonal foraging patterns, which I use as a proxy for species specific thermal tolerances. I apply our "dominance-thermal tolerance model" to a system of three sympatric ant species (Paratrechina terricola, Aphaenogaster rudis and Prenolepis imparis) in an eastern hardwood forest. The model predicts coexistence assuming parameter estimates made from data collected under current climatic conditions. I then consider potential changes in model parameters that might occur as a result of climatic warming. In particular, I focus on altered ant behavior and food availability, and use our model to predict the effects that these changes will have on ant community composition.