Research theme:

How do environmental and genetic factors affect host-parasite coevolution?

We’re interested in how environmental (e.g. spatial structure, fitness costs) and genetic (e.g. specificity, epistasis) factors affect the coevolution of traits such as resistance and infectivity. Using relatively simple eco-evolutionary models, we can study how these factors lead to qualitatively and quantitatively different outcomes, such as optimal strategies, fluctuating selection, arms races, and diversification (simulations below).

Examples of different types of coevolutionary dynamics: optimal strategy (left); fluctuating selection/ cycling (middle); diversification leading to polymorphism (right)

Key findings

Using a variety of mathematical and numerical techniques, we’ve shown how:

Individual-based simulation of coevolution in a spatially-structured population (black=susceptible, green=low resistance, blue=high resistance, white=empty). From Ashby et al. (2014) Am Nat.