Neutrality in the Metaorganism

by Michael Sieber, Luc ía Pita, Nancy Weiland-Bräuer, Philipp Dirksen, Jun Wang, Benedikt Mortzfeld, Sören Franzenburg, Ruth A. Schmitz, John F. Baines, Sebastian Fraune, Ute Hentschel, Hinrich Schulenburg, Thomas C. G. Bosch, Arne Traulsen Almost all animals and plants are inhabited by diverse communities of microorganisms, the microbiota, thereby forming an integrated entity, the metaorganism. Natural selection should favor hosts that shape the community composition of these microbes to promote a beneficial host-microbe symbiosis. Indeed, animal hosts often pose selective environments, which only a subset of the environmentally available microbes are able to colonize. How these microbes assemble after colonization to form the complex microbiota is less clear. Neutral models are based on the assumption that the alternatives in microbiota community composition are selectively equivalent and thus entirely shaped by random population dynamics and dispersal. Here, we use the neutral model as a null hypothesis to assess microbiata composition in host organisms, which does not rely on invoking any adaptive processes underlying microbial community assembly. We show that the overall microbiota community structure from a wide range of host organisms, in particular including previously understudied invertebrates, is in many cases consistent with neutral expectations. Our approach allows to identify individual microbes that a re deviating from the neutral expectation and are theref...
Source: PLoS Biology: Archived Table of Contents - Category: Biology Authors: Source Type: research