Acknowledgements

E.S. was supported by a fellowship from the Josephine De Karman Fellowship Trust and an Alden H. Miller Fellowship from the Museum of Vertebrate Zoology. We thank the DAAD, whose partial PROMOS scholarship made it possible for D.D., J.P. and J.F. to work within the project. This study was supported in part by subsidy funding to the Okinawa Institute of Science and Technology (OIST). We thank Matthew Knope and Mel Johansen for logistical assistance, Sven Künzel for sequencing our samples, and the Nature Conservancy and Department of Land and Natural Resources for access to field sites (permit no. I1298).