Ophelia Venturelli from UW-Madison learns design principles of microbial communities through modelling techniques. By studying pairs of community members and comparing them to model predictions, she can begin to build a picture of community dynamics. When two microbes are introduced in co-culture, there are three options: one dominates, they co-exist, or dominance depends on which one was more abundant at the start of the experiment. These pairwise interactions are then incorporated into a community-level network and can be used to predict co-existence. Phylogenetic relatedness predicts interactions in some bacterial phyla, but not all.
Another way to study community dynamics is removing one member from the community at a time. This approach identified a handful of “driver” organisms, whose absence drastically changed community assembly. These driver organisms would make likely make good targets for manipulation of microbiomes.