ACKNOWLEDGMENTS
We thank P. Taberlet for constructive discussions. This study is funded by the European Research Council under the European Community’s Horizon 2020 Programme, Grant Agreement no. 772284 (IceCommunities). WT, TM and LG also thank the rom the French Agence Nationale de la Recherche (ANR) through the GlobNets (ANR‐16‐CE02‐0009) project and from ‘Investissement d’Avenir’ grant managed by the ANR (Montane: OSUG@2020: ANR‐10‐LAB‐56).