DOI: 10.5061/dryad.c574h
title: Data from: Evolutionary relatedness does not predict competition and co-occurrence in natural or experimental communities of green algae

description: The competition-relatedness hypothesis (CRH) predicts that the strength of
 competition is the strongest among closely related species and decreases
 as species become less related. This hypothesis is based on the assumption
 that common ancestry causes close relatives to share biological traits
 that lead to greater ecological similarity. Although intuitively
 appealing, the extent to which phylogeny can predict competition and
 co-occurrence among species has only recently been rigorously tested, with
 mixed results. When studies have failed to support the CRH, critics have
 pointed out at least three limitations: (i) the use of data poor
 phylogenies that provide inaccurate estimates of species relatedness, (ii)
 the use of inappropriate statistical models that fail to detect
 relationships between relatedness and species interactions amidst
 nonlinearities and heteroskedastic variances, and (iii) overly simplified
 laboratory conditions that fail to allow eco-evolutionary relationships to
 emerge. Here, we address these limitations and find they do not explain
 why evolutionary relatedness fails to predict the strength of species
 interactions or probabilities of coexistence among freshwater green algae.
 First, we construct a new data-rich, transcriptome-based phylogeny of
 common freshwater green algae that are commonly cultured and used for
 laboratory experiments. Using this new phylogeny, we re-analyse ecological
 data from three previously published laboratory experiments. After
 accounting for the possibility of nonlinearities and heterogeneity of
 variances across levels of relatedness, we find no relationship between
 phylogenetic distance and ecological traits. In addition, we show that
 communities of North American green algae are randomly composed with
 respect to their evolutionary relationships in 99% of 1077 lakes spanning
 the continental United States. Together, these analyses result in one of
 the most comprehensive case studies of how evolutionary history influences
 species interactions and community assembly in both natural and
 experimental systems. Our results challenge the generality of the CRH and
 suggest it may be time to re-evaluate the validity and assumptions of this
 hypothesis.
description: Combined Nuclear and
 Chloroplast MatrixThis matrix was used to
 construct the tree presented in Figure 1. The data partitioning scheme is
 the following: Nuclear = 1-14246 Chloroplast =
 14247-19949Combined.phyMaximum Likelihood Tree from combined matrixThis is the tree (figure 1) resulting from the raxml analysis.Combined.treeChloroplast OrthologsResults for Chloroplast genome orthology searchChloroplastOrthologs.phytabNuclear OrthologsResults for Nuclear genome orthology searchNuclearOrthologs.phytabMatrix for Community Phylo TestConcatenated data used to generate the PhyloTest tree. These data were used to test models of phylogenetic community structure in picante.PhyloTest.phyPhylo Test TreeResulting maximum likelihood tree from phylotest matrix. These data were used to test models of phylogenetic community structure in picante.PhyloTest.tree