ACKNOWLEDGEMENTS

We would like to thank G. Sanson and J. Jernvall for discussions and insightful comments on the manuscript. Thanks to museum curators and collections managers for loans of material used in this study: O. Grönwall (Naturhistoriska riksmuseet, Stockholm), R. Asher (Museum für Naturkunde, Berlin), M. Hildén, I. Hanski (Finnish Museum of Natural History). This study was supported by the Academy of Finland and Synthesys.