Infrequent long-range dispersal and evolution of a top terrestrial arthropod predator in the sub-Antarctic

• Published in: The American Naturalist
• Main Authors: Wolff, Jonas O., Kennedy, Susan, Houghton, Melissa, Pascoe, Penelope, Gajski, Domagoj, Derkarabetian, Shahan, Fraser, Ceridwen, Krehenwinkel, Henrik, Renault, David
• Other Authors: Universität Greifswald - University of Greifswald, Macquarie University Sydney, Trier University, University of Tasmania Hobart (UTAS), Masaryk University Brno (MUNI), Harvard University, University of Otago Dunedin, Nouvelle-Zélande, Ecosystèmes, biodiversité, évolution Rennes (ECOBIO), Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2024
• Subjects: [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Antarctic; Myro; The Antarctic; Antarc*
• Online Access: https://hal.science/hal-04649241; https://doi.org/10.1086/730827

International audience The sub-Antarctic terrestrial ecosystems survive on isolated oceanic islands in the path of circumpolar currents and winds that have raged for more than 30 million years and are shaped by climatic cycles that surpass the tolerance limits of many species. Surprisingly little is known about how these ecosystems assembled their native terrestrial fauna and how such processes have changed over time. Here, we demonstrate the patterns and timing of colonization and speciation in the largest and dominant arthropod predators in the eastern sub-Antarctic: spiders of the genus Myro. Our results indicate that this lineage originated from Australia before the Plio-Pleistocenic glacial cycles and underwent an adaptive radiation on the Crozet archipelago, from where one native species colonized multiple remote archipelagos via the Antarctic circumpolar current across thousands of kilometers. The results indicate limited natural connectivity between terrestrial macroinvertebrate faunas in the eastern sub-Antarctic and partial survival of repeated glaciations in the Plio-Pleistocene. Furthermore, our findings highlight that by integrating arthropod taxa from multiple continents, the climatically more stable volcanic Crozet archipelago played a critical role in the evolution and distribution of arthropod life in the sub-Antarctic.