Can species adapt to climatic changes at a rate that matches the rate of climate change? This question is of fundamental importance for understanding the response of species and communities to current climatic changes and future distribution of biodiversity. The main goal of this project is to study evolutionary responses of soil animals to global warming in a natural field setting. In 2008 an earthquake in S-Iceland caused local changes of geothermal systems. This incidence caused previously “cool” areas within two ecosystems (forest and grassland) to suddenly experience geothermal warming resulting in a ~100 m gradient of soil temperatures from ambient to +50 °C. In addition, adjacent grassland also experienced such geothermal warming which has now lasted for a century. These sites provide a unique opportunity to examine if, and at what rate, soil invertebrate species can respond and adapt to rapid global warming in a natural ecosystem.
In order to answer if species have rapidly adapted to warming at these sites, I will study genetic changes in common garden experiments and examine the phenotypic variation in thermal tolerance, desiccation tolerance, growth and reproduction as well as other fitness proxies such as energy reserves in species originating from benign (control) and heated areas. The project will also investigate central physiological traits and mechanisms including metabolic rate, membrane lipid chemistry and membrane fluidity which are directly related to thermal adaptation. I will ask if individuals originating from the heated areas, which have been evolving in increased temperature environments during six and ~100 years, respectively, display phenotypic differences relative to individuals originating from non-heated control areas.
Martin Holmstrup is an AIAS Jens Christian Skou fellow and Professor of soil zoology at the Department of Bioscience, Aarhus University. His research interests are focused on the ecophysiology, ecotoxicology and ecology of invertebrates including physiological and biochemical adaptations to drought and cold stress, and interactions between pollution and climatic stresses.