Scripts of data selection and analysis: role of community size in driving spatial variation in riverine fish metacommunities around the world

Here we describe how we obtained and analyzed data for the study: High compositional dissimilarity among small communities is decoupled from environmental variation (10.32942/osf.io/vngse) We investigated the role of community size in mediate the strength of ecological drift and environmental selection in driving community spatial variation in metacommunities. This is an updated version where we used process-based simulations to identify β-diversity metrics and community-environment measures that were appropriate to investigate the role of those assembly processes along a gradient of community size.