Maintenance of variation in life history traits

Extensive variation in life history traits in the bank vole (Myodes glareolus) is evident. Despite decades of research factors behind this variation are still unclear. My main research interest is in solving whether vole cycles maintain variation in life history traits. My research involves both experimental studies in enclosures and extensive long-term data collected from natural populations.

Island selection in the bank vole is another one of my research interests. Island conditions are expected to favor different life history strategies than mainland conditions and thus lead to rapid evolution. A long-term selection study comparing island individuals to individuals from adjacent mainland populations is in progress. Island and mainland individuals are also compared in experimental setups to provide further proof for fast adaptation to island conditions.


  • Heikki Helle, Tapio Mappes & Esa Koskela

Relevant publications:

  • Helle H., Koskela E. & Mappes T. (2012) Life in varying environments: experimental evidence for delayed effects of juvenile environment on adult life history. Journal of Animal Ecology (in press).