Acknowledgements
We thank L. de Wit for help during tissue collections, G.J.F. Overkamp
for technical assistance, Prof.dr. M.P. Gerkema for establishing the
common vole colony and Dr. C. Dijkstra and Dr. L. van de Zande for
establishing the tundra vole colony at the University of Groningen. This
work was funded by the Adaptive Life program of the University of
Groningen (B050216).