Confronted with fast-paced environmental changes, biota in Antarctic ecosystems are strongly challenged and face three possible outcomes: adaptation, migration or extinction. Past glaciation periods have already forced marine zoobenthos of the SO into refugia, being either ice-free continental shelf areas, the deep sea or sub- or peri-Antarctic regions, followed by recolonization when the ice retreated. The collaborative Belgian BRAIN project RECTO, “Refugia and ecosystem tolerance in the Southern Ocean” (SO), will strive at understanding how such past events have driven diversification and adaptation in different animal groups and how these can be applied as proxies to understand the contemporary situation and predict future scenarios.
In a multidisciplinary approach, RECTO will tackle 6 objectives by combining genomic data with morphological, phylogenetic, coalescent, fossil, physiological, ecological and modelling approaches. RECTO will focus on six different animal groups: fish, sea stars, amphipods, bivalves, ostracods, and seabirds. In this way, RECTO will study different trophic levels ranging from micro- and macro-benthos to pelagic crustaceans and vertebrates. The selected species differ in their biology, life histories and dispersal capacities, which are all factors affecting their abilities to cope with environmental changes. Most of the species occur in the SO but RECTO will also investigate snow patrol colonies living close to the Princess Elisabeth Station.
With a molecular approach, RECTO will produce data on population histories and Pleistocene refugia and test for possible correlations with past climate data to reconstruct how the target taxa responded to past glaciations and interglaciations. For fish and amphipods, RECTO will also study in a novel phylogenetic framework how morphological diversification and trophic adaptability are interacting with each other and whether ecotypes of selected species have faster modes of evolution. Geographic models on future species and trait distributions based on physiological and energy limits and present and future climate data will be refined and integrated with coupled sea-ice-ocean and individual based models for the SO. Finally, scenarios of future dispersive abilities and possible habitat shifts of the RECTO target groups will be developed to infer how the RECTO target species will respond to future climate change.
