Acknowledgements
We are grateful to Dr C. Saraux and Dr B. Warren for helpful comments on
the phylogenetic and statistical analyses. The authors wish to thank Dr
A. Pauliny, Dr D. Lank, Dr M. Enstipp, Dr P. Bize and Dr D. Gremillet
for providing us with personal information on their biological models.
We are grateful to Sebastian Sosa for providing us with R script for the
radial distribution of bird species in relation to Adult TL and
PC axes. FSD thanks the Institute of Advanced Studies of the University
of Strasbourg for their financial support through an USIAS fellowship,
and the Région Grand Est and the Eurométropole de Strasbourg for the
award of a Gutenberg Excellence Chair that supported this project.