1. School of Biological Sciences, Edinburgh University, Mayfield Road, Edinburgh EH9 3JH, UK
2. Synthetic & Systems Biology Centre, C. H. Waddington Building, King’s Buildings, Edinburgh EH9 3JD, UK
3. Deep Springs College, CA 93513, USA
4. School of GeoSciences, Crew Building, King’s Buildings, West Mains Road, Edinburgh EH9 3JN, UK
5. Department of Agronomy, Kansas State University, Manhattan, KS 66506, USA
6. Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA