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S. Renaud and J. R. Michaux

(Lenormand, 2002). However, genetic mixing over Europe is
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ACKNOWLEDGEMENTS
Davis, M.B. & Shaw, R.G. (2001) Range shift and adaptive
We thank Thomas Cucchi for numerous fruitful discussions responses to Quaternary climate change. Science, 292, 673–
and comments. The reviews of N. Navarro and J.-D. Vigne 679.
were very constructive and greatly contributed to the improve- Dayan, T. & Simberloff, D. (1998) Size patterns among com-
ment of this manuscript. The final version of the manuscript petitors: ecological character displacement and character
benefited from the comments of Julie Prytulak, especially release in mammals, with special reference to island popu-
regarding the proper use of the English language. This research lations. Mammal Review, 28, 99–124.
was supported by IFB, GDR 2474 CNRS ‘Morphome ´trie et Duarte, L.C., Monteiro, L.R., Von Zuben, F.J. & Dos Reis, S.F.
Evolution des Formes’, Re ´gion-Rho ˆne-Alpes, and Belgian (2000) Variation in mandible shape in Thrichomys aper-
FNRS. eoides (Mammalia: Rodentia): geometric analysis of a

352 Journal of Biogeography 34, 339–355
ª 2006 The Authors. Journal compilation ª 2006 Blackwell Publishing Ltd