Chalmers Conferences, 9th European Conference on Mathematical and Theoretical Biology

Co-evolutionary cycles in host-parasite interactions
Alex Best

Last modified: 2014-06-09


Understanding how the environment impacts the evolution and spread of infectious disease is a major interdisciplinary challenge. Recent experimental work has found that under certain environmental conditions antagonistic co-evolution between hosts (bacteria) and parasites (phage) can exhibit fluctuating selection rather than a directional ‘arms-race’. This has important implications for management strategies as such cycles mean the parasite is a ‘moving target’. It is therefore crucial that we develop theory that can reveal the environmental conditions that promote co-evolutionary cycles. I shall first introduce an epidemiological model that reflects the infection process of the bacteria-phage system. Working within the framework of adaptive dynamics, I will then take a bifurcation approach to explore the environmental conditions that favour the creation of co-evolutionary cycles. Throughout, I shall link the findings from my mathematical models to those from experimental data.


Co-evolution, host-parasite interactions, adaptive dynamics