DOI: 10.5061/dryad.4xgxd2555
title: Genetic evidence further elucidates the history and extent of badger introductions from Great Britain into Ireland

description: The colonization of Ireland by mammals has been the subject of extensive
 study using genetic methods and forms a central problem in understanding
 the phylogeography of European mammals after the Last Glacial Maximum.
 Ireland exhibits a de-pauperate mammal fauna relative to Great Britain and
 continental Europe, and a range of natural and anthropogenic processes
 have given rise to its modern fauna. Previous Europe-wide surveys of the
 European badger (Meles meles) have found conflicting microsatellite and
 mitochondrial DNA evidence in Irish populations, suggesting Irish badgers
 have arisen from a combination of populations with close relationships in
 Great Britain and in Scandinavia, and admixture between recently
 introduced and longer established populations. The extent and history of
 contact between British and Irish badger populations, however, remains
 unclear.  We use comprehensive genetic data from Great Britain
 and Ireland to demonstrate that badgers in Ireland’s northeastern and
 southeastern counties are genetically similar to contemporary British
 populations.  Simulation analyses suggest this admixed population
 arose in Ireland 600-700 (CI 100-2600) years before the present most
 likely through the introduction of British badgers by people. These
 findings add to our knowledge of the complex colonization history of
 Ireland by mammals, and the central role of humans in facilitating it.
description: Tissue samples (muscle) from badgers were collected from ongoing
 road traffic accident tuberculosis surveys in Northern Ireland and badger
 culling in the Republic of Ireland. DNA was extracted
 and subjected to genotyping of 14 microsatellite markers using capillary
 gel electrophoresis. Genotype data was analysed using
 STRUCTURE to determine hierarchical clustering in genetic data,
 discriminant analysis of principal components (DAPC) with basic population
 genetic statistics determined using standard computational
 tools.
description: # Genetic evidence further elucidates the history and extent of badger
 introductions from Great Britain into Ireland
 [https://doi.org/10.5061/dryad.4xgxd2555](https://doi.org/10.5061/dryad.4xgxd2555) ## Description of the data and file structure Data from 545 badger tissue samples genotyped at 14 microsatellite markers. General location data included (UK County level). GPS coordinates for Irish badgers are included as Irish Grid references. Discriminant Analysis of Principal Components (DAPC) cluster membership (clusters 1-14) is indicated. Structure K=2 percentage membership also included. ### Files and variables #### File: Supplementary\_Data\_1.xlsx **Description:** 545 badger tissue samples with genetic typing microsatellite data for 14 markers (biallelic). GPS and general location data, plus DAPC cluster membership and K=2 Structure cluster membership. ##### Variables * Local ID - unique isolate number * Index - occurrence in dataset * X - coordinate from Irish grid * Y -  coordinate from Irish grid * County - UK and Irish county general location * Mel104 - microsatellite locus * Mel106 - microsatellite locus * Mel109 - microsatellite locus * Mel111 - microsatellite locus  * Mel112 - microsatellite locus * Mel117 - microsatellite locus * Mel102- microsatellite locus * Mel105 - microsatellite locus * Mel113 - microsatellite locus * Mel115 - microsatellite locus * Mel129 - microsatellite locus * Mel103 - microsatellite locus * Mel110 - microsatellite locus * Mel114 - microsatellite locus * DAPC group membership - discriminant analysis of principal components cluster membership (1-14) * GB pop 1 - Structure output - the proportion of isolate with GB signature genetic heritage * Ire pop 2 -  Structure output - the proportion of isolate with Irish signature genetic heritage ## Code/software N/A