Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Like larger organisms, microorganisms display distinct distributions in space and time. Martiny, Hanson and colleagues propose that four processes — selection, drift, dispersal and mutation — can shape such microbial biogeographic patterns, and analyse the literature to assess the evidence for their importance in shaping one pattern, the distance–decay relationship.
Many bacteria in a variety of niches contain cellulases. Such microorganisms are primarily considered to be saprophytic, but recent evidence suggests that cellulases are also present in non-saprophytes. By examining the genomes of ∼1,500 bacteria, Henrissat and colleagues confirm this observation and reveal unusual roles for some cellulases.