Antarctica as an evolutionary arena during the Cenozoic global cooling

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Condamine, Fabien L., Kergoat, Gael, J.
• Other Authors: Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement IRD : UR226-Centre National de la Recherche Scientifique (CNRS), Centre de Biologie pour la Gestion des Populations (UMR CBGP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD France-Sud )-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: [SDV.BID]Life Sciences [q-bio]/Biodiversity; Antarc*; Antarctic; Antarctica; Tundra
• Online Access: https://hal.science/hal-03367498; https://hal.science/hal-03367498/document; https://hal.science/hal-03367498/file/Condamine%20%26%20Kergoat%20-%20PNAS%20merged.pdf; https://doi.org/10.1073/pnas.2108886118

International audience It is striking to observe that species richness is not evenly distributed across the surface of the planet. Current species diversity indeed decreases toward the poles, with Antarctica for instance being depauperate compared to tropical regions. This ubiquitous pattern has long attracted the attention of naturalists and more recently of evolutionary biologists and paleontologists to understand why species diversity peaks at the equator. However, it remains poorly understood how polar biodiversity originated and diversified. Antarctica is currently defined as three large biogeographic regions: the Maritime Antarctic, the sub-Antarctic, and the Continental Antarctic. The Maritime Antarctic region is largely separated from the rest of the world’s oceans due to the Antarctic Circumpolar Current (ACC), differences in temperature along the Antarctic Polar Front (APF), and the presence of a deep sea surrounding the Antarctic shelf (1). The sub-Antarctic region consists of dozens of islands contained within the APF, generally characterized by the presence of tundra (absent from the Continental Antarctic) and fellfield habitats. As for the Continental Antarctic region, it is mostly uninhabitable, with less than 0.5% of its surface being ice-free. A long-standing idea is that biodiversity in Antarctica is low, and only constituted of old and poorly diversified lineages. In PNAS, a study (2)—relying on both microevolutionary and macroevolutionary approaches—challenges this idea and shows that terrestrial life can thrive there.