 Moving away from a focus on single organisms or monogenomic species allows us to make better sense of many recent findings in microbiology (in which metagenomics has played a key role). Central to all of this are mobile DNA elements that can travel horizontally, meaning between different members of a community (including between different kinds of organisms). Obtaining such mobile DNA elements can have a crucial effect on the survival and reproduction capacity of the recipient cell. Mobile DNA can therefore be a key element in the evolutionary processes as it becomes a ‘communal resource’ (McFall-Ngai et al. 2013). Acquired antibiotic resistance is only one of many benefits cells are known to obtain through acquired DNA elements.