Kerguelen Islands: a living laboratory to understand the benthic biodiversity of the Antarctic

• Main Authors: Feral, Jean-Pierre, Poulin, Elie
• Other Authors: Diversité, évolution et écologie fonctionnelle marine (DIMAR), Centre National de la Recherche Scientifique (CNRS)-Université de la Méditerranée - Aix-Marseille 2, Laboratorio de Ecología Molecular (LEM), Instituto de Ecología y Biodiversidad (IEB), Guy Duhamel & Dirk C. Welsford
• Format: Other/Unknown Material
• Language: English
• Published: HAL CCSD 2010
• Subjects: Brooding invertebrates; Coastal communities; Southern ocean; Biodiversity; reproduction mode; dispersal; connectivity; marine functional ecology and evolution; Biodiversité; écosystèmes côtiers; Océan Austral; mode de reproduction; dispersion; connectivité; évolution et écologie fonctionnelle marine; geo; envir; Antarctic; Austral; Îles Kerguelen; Kerguelen; Kerguelen Island; Kerguelen Islands; Southern Ocean; The Antarctic; Antarc*; Antarctique*
• Online Access: https://hal.archives-ouvertes.fr/hal-01790635/file/2011_F%C3%A9ral_Kerguelen%20Plateau_pr_Kerguelen%20Islands-%20a%20living%20laboratory%20to%20understand%20the%20benthic%20biodiversity%20of%20the%20Antarctic.pdf; https://hal.archives-ouvertes.fr/hal-01790635

International audience The high proportion of brooding (50 to 70% depending on phyla) compared with broadcaster species among invertebrates living along the coast of the Southern ocean has been traditionally interpreted as an adaptation to local environmental conditions. Currently, however, species with a planktotrophic developmental mode are ecologically dominant along coastal areas, in terms of abundance of individuals. The fact that Kerguelen island is inhabited by such species and that the French base Port-aux-Français, with its equipped marine laboratory, made it possible to address questions as to why are there so many brooders in the coastal waters of the Southern ocean and if the apparent ecological success of broadcasters related to their developmental mode. We argue that the present shallow antarctic benthic invertebrate fauna is the result of two processes acting at different temporal scales. First, the high proportion of brooding species compared with coastal communities elsewhere corresponds to species-level selection occurring over geological and evolutionary times which explains the very high biodiversity observed in coastal waters. Second, the ecological dominance of broadcasters is the result of processes operating at ecological timescales that are associated with the advantage of having pelagic larvae under highly disturbed conditions (e.g., ice scouring). rÉsUMÉ.-les îles Kerguelen : un laboratoire vivant pour la compréhension de la biodiversité benthique en antarctique. la proportion élevée (50 à 70% selon les phylums) d'espèces incubantes comparée à celle des espèces dispersantes d'invertébrés vivant dans les eaux côtières de l'océan austral a été traditionnellement interprétée comme une adaptation aux conditions environnementales locales. Cependant, de nos jours, les espèces à développement planctotrophique y sont écologiquement dominantes, en termes d'abondance. le fait que les îles Kerguelen abritent de telles espèces et que la base de Port-aux-Français possède un véritable laboratoire ...