ABSTRACT
The repeated, independent evolution of similar traits in different species is a fascinating phenomenon that affords deep insights into the relative importance of deterministic vs. stochastic forces in evolution. While there are many well-known examples of convergent evolution in animals and plants, in bacteria, resistance to antibiotics can also be highly parallel, with the same mutations causing resistance in unrelated species. In this talk, I will first present results from an in silico study screening ~18,000 bacterial species for the evolvability and intrinsic presence of resistance to rifampicin (an important antibiotic used to treat tuberculosis). I will then discuss experimental results comparing the mutational spectrum and fitness effects of rifampicin resistance across three species of bacteria. Our findings indicate that all bacteria are expected to be similarly able to evolve rifampicin resistance through single point mutations. However, the evolvability and induced fitness effects of individual resistance mutations can vary substantially across species, highlighting the importance of mutational constraints and epistatic effects.

BIOGRAPHY 
I am broadly interested in the evolutionary biology of sexual processes, parasitism, and the interplay between these phenomena. Most of my work involves mathematical models, but I also do experimental and field work. Currently, my research focuses on the following topics:

• Reproductive parasites. These parasites, which include the famous bacterium Wolbachia, infect many insect species and manipulate the reproduction of their hosts in fascinating ways.
• Recombination in bacteria. Bacteria reproduce clonally, but many still exchange genes with other bacteria, for example through plasmids or the uptake of free DNA from the environment. I'm especially interested in how recombination can affect the evolution of antibiotic resistance in bacteria.
• Host-parasite coevolution. Hosts and parasites interact in an antagonistic manner, which may produce interesting coevolutionary dynamics. I am also scrutinizing the Red Queen hypothesis, which posits that host-parasite coevolution can produce selection for recombination and sexual reproduction.
• Parthenogenesis in animals. Although most animals reproduce sexually, some species have given up sex and consist of asexually reproducing females only. I am interested in the factors that enhance or inhibit the evolution of such parthenogenetic species and on their long-term evolutionary fate.