RT Journal Article SR Electronic T1 Emergent Simplicity in Microbial Community Assembly JF bioRxiv FD Cold Spring Harbor Laboratory SP 205831 DO 10.1101/205831 A1 Joshua E. Goldford A1 Nanxi Lu A1 Djordje Bajic A1 Sylvie Estrela A1 Mikhail Tikhonov A1 Alicia Sanchez-Gorostiaga A1 Daniel Segrè A1 Pankaj Mehta A1 Alvaro Sanchez YR 2017 UL http://biorxiv.org/content/early/2017/10/19/205831.abstract AB Microbes assemble into complex, dynamic, and species-rich communities that play critical roles in human health and in the environment. The complexity of natural environments and the large number of niches present in most habitats are often invoked to explain the maintenance of microbial diversity in the presence of competitive exclusion. Here we show that soil and plant-associated microbiota, cultivated ex situ in minimal synthetic environments with a single supplied source of carbon, universally re-assemble into large and dynamically stable communities with strikingly predictable coarse-grained taxonomic and functional compositions. We find that generic, non-specific metabolic cross-feeding leads to the assembly of dense facilitation networks that enable the coexistence of multiple competitors for the supplied carbon source. The inclusion of universal and non-specific cross-feeding in ecological consumer-resource models is sufficient to explain our observations, and predicts a simple determinism in community structure, a property reflected in our experiments.