Seminar Summary - Eco-evolutionary feedbacks play a powerful role in shaping the trajectory of change in ecological communities. Developing general theory to predict these trajectories would enable a wide variety of innovations in fields ranging from evolutionary medicine to agriculture. I will discuss two vignettes from my lab's work towards developing this theory. First, a critical step is identifying the ecological interactions that are currently occurring. To this end, we are exploring the possibility of identifying game theoretic interactions among cancer cells via spatial pattern analysis. A necessary second component is predicting how co-evolution will shape ecological interactions over time. We are studying this problem in the context of host-endosymbiont co-evolution, using an agent-based computational model. Specifically, I will present our results on the impact of partner choice on the de novo evolution and stability of mutualism, and how this impact is affected by the mutational landscape of the trait governing partner choice.