“I was among the first to formulate clear and testable hypotheses for how alpine plants could have survived glaciations...”

Since the end of the 19th century, there has been a long debate about the fate of the mountain flora of central Europe during the Pleistocene ice ages; however, the choice of tools to address these questions was limited. Using new molecular approaches, several research groups from different countries started to work on this topic. I was among the first to formulate clear and testable hypotheses for how alpine plants could have survived glaciations and was able, for the first time, to provide strong support for the survival of an alpine plant species on mountains rising above the ice in parts of the European Alps formerly most heavily glaciated.

I was always intrigued by how alpine plants could have survived the past dramatic climate fluctuations of the Quarternary ice ages. How did they respond to these rapid climate changes, where were their refugia? With the knowledge on how and where alpine plants survived ice ages, it is potentially possible to estimate their capacity to react to present climate changes and to evaluate the speed of recolonization of unoccupied areas. Long periods of isolation are also intriguing from the aspect of allopatric speciation. At one point I came across old literature (late 19th and early 20th century) formulating hypotheses of glacial survival for alpine plants without really being able to test them with adequate methods. So I chose four alpine species with different distribution patterns, ecological preferences, and reproductive systems to test these long-standing hypotheses.

The genetic structure of populations of the high-alpine cushion plant Eritrichium nanum (Alpine Forget-Me-Not) in the central parts of the Alps, which have been most intensely glaciated during Pleistocene ice ages, suggests in situ survival in isolated snow-free patches on mountains rising above the ice. This result is among the first to show the capacity of alpine plants to resist the hostile climate during Pleistocene glaciation.