Fig. 2

The probability that the A-type will be fixed in a new recipient group as a function of \(\pi\). Estimates for the probability of A-type fixation were generated by running the stochastic population model on populations with \(\pi \in \left\{0.05, 0.10,\dots , 0.95\right\}\) for each value of \({R}_{in}\in \left\{5, 50\right\}\). Each \(\left(\pi ,{R}_{in}\right)\) pair was run \({10}^{5}\) times. Probabilities under neutrality (i.e., when \(\delta =1\)) are approximated by the dashed one-to-one line. Note that \(\pi\) is the proportion of A-types in a recipient group regardless of the identity of that group. It therefore plays the role of either \({\pi }_{AS}\) or \({\pi }_{SA}\) when predicting the probability of A-type fixation