Polar lake microbiomes have distinct evolutionary histories

• Published in: Science Advances
• Main Authors: Tytgat, Bjorn, Verleyen, Elie, Sweetlove, Maxime, Van Den Berge, Koen, Pinseel, Eveline, Hodgson, Dominic, Chown, Steven, Sabbe, Koen, Wilmotte, Annick, Willems, Anne, Vyverman, Wim
• Other Authors: InBios - Integrative Biological Sciences - ULiège BE
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Association for the Advancement of Science (AAAS) 2023
• Subjects: biogeography; SSU rRNA; microbial diversity; Polar Regions; Antarctica; Arctic; Sub-antarctic; Life sciences; Environmental sciences & ecology; Microbiology; Aquatic sciences & oceanology; Sciences du vivant; Sciences de l’environnement & écologie; Microbiologie; Sciences aquatiques & océanologie; Antarc*; Antarctic
• Online Access: https://orbi.uliege.be/handle/2268/308903; https://orbi.uliege.be/bitstream/2268/308903/1/_sciadv.ade7130.pdf; https://doi.org/10.1126/sciadv.ade7130

peer reviewed Toward the poles, life on land is increasingly dominated by microorganisms, yet the evolutionary origin of polar microbiomes remains poorly understood. Here, we use metabarcoding of Arctic, sub-Antarctic, and Antarctic lacustrine benthic microbial communities to test the hypothesis that high-latitude microbiomes are recruited from a globally dispersing species pool through environmental selection. We demonstrate that taxonomic overlap between the regions is limited within most phyla, even at higher-order taxonomic levels, with unique deep-branching phylogenetic clades being present in each region. We show that local and regional taxon richness and net diversification rate of regionally restricted taxa differ substantially between polar regions in both microeukaryotic and bacterial biota. This suggests that long-term evolutionary divergence resulting from low interhemispheric dispersal and diversification in isolation has been a prominent process shaping present-day polar lake microbiomes. Our findings illuminate the distinctive biogeography of polar lake ecosystems and underscore that conservation efforts should include their unique microbiota. CCAMBIO 14. Life below water