Acknowledgements
We thank the Deutsche Forschungsgemeinschaft that funded this project with a grant to BF (DFG FE 1333/6-2) and SF (DFG FO 298/19-2) within the research unit FOR-2281. We are grateful to Matteo Negroni for his help during ant collection. We thank our technician Marion Kever for assistance during dissections and RNA extraction. We are very grateful to Marah Stoldt for her precious help with the analysis of the transcriptomic data. Thanks to the Southwestern Research Station (Portal, Arizona) for the support to obtain an ant collection permit from the Coronado National Forest.