Incipient speciation through ecological divergence in subarctic whitefish populations

The evolutionary processes that can create two species out of one are still under exploration and continuous debate. Recent developments have emphasised the potential of ecological speciation where species divergence may develop as an evolutionary consequ ence of ecological interactions within the ancestral population. The present project explores the evolution of polymorphic European whitefish Coregonus lavaretus in postglacial lakes of northern Europe by integrating ecological, molecular, morphometrical and experimental approaches. Postglacial lakes provide excellent cases for studying incipient processes in ecological speciation as they are young in evolutionary time and are replicated many times as discrete, but variable entities in the landscape. Data will be retrieved from a large cluster of subarctic whitefish lakes in northern Norway and Finland for a comprehensive analysis of key processes in polymorphism and speciation. Analyses include i) spatial distribution patterns of whitefish morphs in rela tion to postglacial colonisation history and abiotic and biotic environmental characteristics, ii) genetic differentiation, reproductive isolation and life history variation among whitefish morphs, and iii) divergence in functional morphology and resource polymorphism within and between whitefish morphs and lakes.