rtz for posing a question which led to the model pre- sented in Table 3 and Fig. 10. This work was supported in part by grants N00014-16-1-2914 from the US Office of Naval Research. EFTA00810756 J. Waketey and M. Nowak/Theoretical Population Biology 125 (2019)38-55 53 55832 from the John Templeton Foundation and W911 NF-18-