“…Understanding these potential costs will be key as phage therapy becomes a more common method for controlling pathogenic bacterial populations (Goodridge, 2004;Levin and Bull, 2004). More generally, these results add to a growing body of work across a range of taxa that points to the wide range of host fitness traits correlated with pathogen resistance (Boots and Begon, 1993;Ferdig et al, 1993;Fellowes et al, 1998;Langand et al, 1998;Williams et al, 1999;Yourth et al, 2002;Lythgoe and Chao, 2003;Sanders et al, 2005;Zhong et al, 2005;Buckling et al, 2006;Morgan et al, 2009). This method of combining natural observations with laboratory selection experiments shows promise in furthering our understanding of the importance of phages, and other selective pressures, as drivers of bacterial evolution and diversity in natural environments.…”