| Autor: |
Weston JNJ; School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne NE1 7RU, UK., Jensen EL; School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne NE1 7RU, UK., Hasoon MSR; Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne NE1 7RU, UK., Kitson JJN; School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne NE1 7RU, UK., Stewart HA; British Geological Survey, Lyell Centre, Research Avenue South, Edinburgh EH14 4AP, UK.; School of Energy, Geoscience, Infrastructure and Society, Institute of Life and Earth Sciences, Heriot-Watt University, Edinburgh, UK, EH14 4AS, UK., Jamieson AJ; Minderoo-UWA Deep-Sea Research Centre, School of Biological Sciences and Oceans Institute, The University of Western Australia (M090), 35 Stirling Highway, Perth, WA 6009. |
| Abstrakt: |
The deepest marine ecosystem, the hadal zone, hosts endemic biodiversity resulting from geographic isolation and environmental selection pressures. However, the pan-ocean distribution of some fauna challenges the concept that the hadal zone is a series of isolated island-like habitats. Whether this remains true at the population genomic level is untested. We investigated phylogeographic patterns of the amphipod, Bathycallisoma schellenbergi , from 12 hadal features across the Pacific, Atlantic, Indian, and Southern oceans and analyzed genome-wide single-nucleotide polymorphism markers and two mitochondrial regions. Despite a cosmopolitan distribution, populations were highly restricted to individual features with only limited gene flow between topographically connected features. This lack of connectivity suggests that populations are on separate evolutionary trajectories, with evidence of potential cryptic speciation at the Atacama Trench. Together, this global study demonstrates that the shallower ocean floor separating hadal features poses strong barriers to dispersal, driving genetic isolation and creating pockets of diversity to conserve. |
