Table 2.

Network preferences for local calls versus foreign calls. (The network's population is also the population of the local call. The preference for local calls was assessed in two ways. First, mean response to local calls is compared with the null expectation of 0 if networks respond equally strongly to local and foreign calls. Second, mean response to local calls is compared to a null expectation that is the mean response to independently evolved calls from replicates of the networks' own population type. This latter contrast controlled for the possibility that networks may have been generally selective against foreign calls, not just those that diverged due to character displacement. Means and confidence intervals of preference strength for local calls from these pairings are displayed in figure 2.)

network's population	population of foreign call	t29 (p value); H0: local call preference =0	t29(p value), H0: local call preference=preference for calls from other replicatesa
A	AB	21.48 (<0.0001)b	17.96 (<0.0001)b
AC	9.46 (<0.0001)b	6.70 (<0.0001)b
AB	A	9.06 (<0.0001)	3.24 (0.003)
AC	10.72 (<0.0001)	4.29 (0.0002)
AC	A	8.32 (<0.0001)b	−1.04 (0.31)b
AB	10.58 (<0.0001)	6.71 (<0.0001)

^aAverage preference for local calls when presented with calls from other replicates by networks in A; 0.027, AB; 0.310, AC; 0.203.

^bAnalysis used transformed data to meet parametric assumptions.