Acknowledgements
Many thanks to the following for various kind help and assistance: Len Ellis (BM), Thomas Kiebacher (University of Zurich), Jurgen Nieuwkoop and Björn Sieberer. Thanks also to the landowners of Wicken Pond (Norfolk Wildlife Trust) for access permission, and to reviewers for helpful comments.
ORCID
Des A. Callaghan http://orcid.org/0000-0002-0415-1493