DOI: 10.5061/dryad.qfttdz0fk
title: Genomic insights into the origin of trans-Mediterranean disjunct distributions: The case of the saltmarsh band-winged grasshopper (Mioscirtus wagneri)

description: Aim: Two main biogeographic hypotheses have been proposed to
 explain the Mediterranean-Turanian disjunct distributions exhibited by
 numerous steppe-dwelling organisms, namely (i) dispersal during the
 Messinian salinity crisis (∼5.96-5.33 Ma) followed by range fragmentation
 and vicariance, and (ii) Pleistocene colonization and recent processes of
 population subdivision (&lt;2 Ma). Despite the two hypotheses
 postulate the role of climatic alterations and changes in landmass
 configuration on determining such disjunct distributions, estimates of the
 timing of lineage diversification have not been complemented so far with
 spatially-explicit tests providing independent evidence on the proximate
 processes underlying geographical patterns of population genetic
 connectivity/fragmentation. Location: Mediterranean-Turanian
 region Taxon: Saltmarsh band-winged grasshopper (Mioscirtus
 wagneri) Methods: We integrate different sources of genetic
 (mtDNA and ddRADseq) and spatial information (configuration of emerged
 lands and niche modelling) to evaluate competing hypotheses of lineage
 diversification in the saltmarsh band-winged grasshopper, a halophile
 species showing a classical Mediterranean-Turanian disjunct distribution.
 Results: Phylogenomic analyses reveal the presence of two North
 African cryptic lineages and support that trans-Mediterranean populations
 of the species diverged in the Pleistocene, with evidence of
 post-Messinian permeability of the Strait of Gibraltar to gene flow likely
 associated with sea level drops during glacial periods. Accordingly,
 spatial patterns of genetic differentiation are best explained by a
 scenario of population connectivity defined by the configuration of
 emerged landmasses and environmentally suitable habitats during glacial
 periods, a time when effective population sizes of the species peaked as
 inferred by genomic-based demographic reconstructions. Main conclusions:
 Our results support post-Messinian colonization and Pleistocene
 diversification as the biogeographic scenario best explaining the
 trans-Mediterranean disjunct distributions of halophilous organisms.
description: <strong>Sampled populations and
 individuals</strong><br> Description of individual and
 population codes used in the different analyses and genomic
 datasets.<br> <em>Samples.xlsx</em>
 <br> <strong>BEAST input
 file</strong><br> Input file (NEXUS format) used for
 phylogenetic analyses in BEAST based on a concatenated database containing
 12S and 16S mitochondrial gene fragments<br>
 <em>InputFile_BEAST_mtDNA.nex</em>
 <br> <strong>SVDquartets input
 file</strong><br> Input file (NEXUS format) used for
 phylogenomic analyses in SVDquartets<br>
 <em>InputFile_SVDquartets.nex</em>
 <br> <strong>FASTSTRUCTURE input
 file</strong><br> Input file (str. format) used for analyses
 of genetic structure in FASTSTRUCTURE<br>
 <em>InputFile_FastStructure.str</em>
 <br> <strong>DNAsp input
 file</strong><br> Input file (alleles. format) used for
 calculating nucleotide diversity per population in DNAsp<br>
 <em>InputFile_DnaSP_DEF.alleles</em>
 <br> <strong>BPP input files</strong><br>
 This ZIP folder contains the input files (genetic datasets and control and
 map files) to perform BPP analyses<br>
 <em>BPP.zip</em> <br>
 <strong>StarwayPlot input files</strong><br> This ZIP
 folder contains the "blueprint" files to perform StarwayPlot
 analyses for each population<br>
 <em>StarwayPlot.zip</em> <br>
 <strong>Isolation-by-resistance (IBR)
 scenarios</strong><br> This ZIP folder contains the “ASC.”
 files corresponding to the isolation by resistance (IBR) scenarios based
 on the spatial configuration<br> of emerged lands (sea level) during
 the present-day, last glacial maximum (LGM), and Messinian, and the
 spatial configuration of<br> climatically suitable habitats as
 inferred from projections of an environmental niche model (ENM) to
 present-day and LGM bioclimatic conditions.<br> This folder also
 contains a “flat landscape” scenario (equivalent to an
 isolation-by-distance scenario) whose pixels (including sea water and
 emerged lands)<br> have a fixed resistance (=1) value.<br>
 <em>IBR_scenarios.zip</em>