In the face of the rapid, ongoing environmental changes of the Baltic Sea, the survival of marine species is challenged. The potential for a species to adapt to a changing environment is given by its plasticity, demography and genetic diversity. Recent research shows that many of the Baltic Sea species are genetically isolated and have reduced genetic diversity, and hence have a lower adaptive potential than, for example, Atlantic populations (e.g. Johannesson & André 2006 Mol Ecol). In light of this and the expected rapid change of the Baltic Sea environment (see below), it will be critical to as soon as possible manage the Baltic Sea species in an optimal way to mitigate losses of biodiversity.
Climate change will have unprecedented consequences for the Baltic Sea ecosystem. Already today, there is a measurable decrease in salinity and an increase in temperature, with further and more dramatic changes predicted (Meier 2006 Climate Dynamics).
One approach to evaluate effects of climate change on organisms has been to use “climate envelope models” (e.g. Cheung et al. 2009 Fish & Fisheries). However, such models do not take into account the potential of evolutionary change of a species. Neither do these models take into account population demography, connectivity and species interactions, and thus may seriously misjudge the potential of species to resist rapid climate change (Chevin et al. 2010 PLoS Biology).
It is quite obvious that environmental changes impose novel types of selection pressure on individuals and species, and if there is genetic variation for traits affecting fitness, selection will result in evolutionary changes and species may become better adapted to the new environment (Wirgin et al. 2011 Science , Hoffmann & Sgro 2011 Nature, Lohbeck ..Reusch 2012 Nature Geoscience). It is now clear that evolutionary changes may act rapidly in a time scale relevant to climate changes. But how often will adaptation happen? And how do we conserve potentials of adaptation?
Our overall goal is to assess and improve capacities of marine species to deal with the current challenge of a rapidly changing Baltic Sea environment.
To reach this goal we need to understand the potential of organisms to evolve new adaptations and how management should be framed to support this.
This project will target an ecologically important Baltic Sea species that contributes with ecosystem functions (eg.primary production), and constitute a dominant part of a Baltic Sea ecosystem. These species also work as experimentally tractable model for evolutionary studies.