DOI: 10.5061/dryad.gr6qb4h
title: Data from: Parthenogenetic vs. sexual reproduction in oribatid mite communities

description: The dominance of sex in Metazoa is enigmatic. Sexual species allocate
 resources to the production of males, while potentially facing negative
 effects such as the loss of well-adapted genotypes due to recombination,
 and exposure to diseases and predators during mating. Two major hypotheses
 have been put forward to explain the advantages of parthenogenetic vs.
 sexual reproduction in animals, i.e. the Red Queen hypothesis and the
 Tangled Bank/Structured Resource Theory of Sex. The Red Queen hypothesis
 assumes that antagonistic predator - prey / parasite - host interactions
 favor sex. The Structured Resource Theory of Sex predicts sexual
 reproduction to be favored if resources are in short supply and aggregated
 in space. In soil a remarkable number of invertebrates reproduces by
 parthenogenesis, and this pattern is most pronounced in oribatid mites
 (Oribatida, Acari). Oribatid mites are abundant in virtually any soil
 across very different habitats, and include many sexual and
 parthenogenetic (thelytokous). Thereby, they represent an ideal model
 group to investigate the role of sexual vs. parthenogenetic reproduction
 across different ecosystems and habitats. Here, we compiled data on
 oribatid mite communities from different ecosystems and habitats across
 biomes, including tropical rainforests, temperate forests, grasslands,
 arable fields, salt marshes, bogs, caves and deadwood. Based on the
 compiled dataset we analyzed if the percentage of parthenogenetic species
 and the percentage of individuals of parthenogenetic species are related
 to total oribatid mite density, species number and other potential driving
 factors of the reproductive mode including altitude and latitude. We then
 interpret the results in support of either the Red Queen hypothesis or the
 Structured Resource Theory of Sex. Overall, the data showed that low
 density of oribatid mites due to harsh environmental conditions is
 associated with high frequency of parthenogenesis supporting predictions
 of the Structured Resource Theory of Sex rather than the Red Queen
 hypothesis.
description: 006 Appendix Figure S1
 May19 newFigure S1: Density
 corrected (x-axis) is the residuals of the regression between density
 (dependent) and PCoA axes used to extract information on the phylogenetic
 correlation between the species of the analyzed communities. The % of
 parthenogenetic species or individual corrected (y-axis) is, again, the
 residuals of a regression between the PCoA axes and the original % values.
 The regression lines in this figure are thus corrected for phylogenetic
 correlation, although we could only approximate phylogenetic distance
 using taxonomic distance and we inferred the latter from the current view
 of the taxonomic hierarchy of Oribatida (according to Norton and
 Behan-Pelletier 2009).007 Appendix Table S1
 The Dataset May 19Table S1: Density,
 occurence, reproductive mode (sex=sexual; parthen=parthenogenetic) and
 phylogenetic affiliation of oribatid mite species from 37 different
 habitats; and characteristics of those habitats (altitude, latitude,
 percentage of parthenogenetic individuals (p_indiv), percentage of
 parthenogenetic taxa (p_taxa), oribatid mite species number (sp_nr), and
 density). Full citations of all papers are given below the table.
 Phylogenetic grouping was done in accordance with Norton &
 Behan-Pelletier (2009).008 Appendix Table S2
 May 19Table S2. Correlation
 matrix (Pearson’s coefficient) linking key variables (i.e., % of
 parthenogenetic individual and species, species number and total oribatid
 density) to each other and the first 6 PCoA axes extracted from the
 taxonomic distance matrix used to approximate phylogenetic relatedness of
 species. Bold values were statistically significant at p &lt; 0.05. Given
 this matrix, we chose PCoA2 as the phylogenetic correction factors to
 regress % of parthenogenetic individual and % of parthenogenetic species
 against density (Fig. S1), species number and also altitude and latitude
 (not shown, correlations not significant).