Acknowledgements
We would like to thank Jessica Lingley for assistance in the analysis of the fat content of pupae and Glyn Vale for review of a final draft of the manuscript, and John Hargrove, Matt Keeling and Kat Rock for general discussion. We thank Daniel May for digitising the LSTM tsetse colony lab books which provided important pilot data for our experiments. The research was funded by the Biotechnology and Biological Sciences Research Council, grant numbers BB/P005888/1 and BB/P006159/1. SE was supported by a Royal Society Dorothy Hodgkin Fellowship (DH140236).