Fig. 6
From: Oviposition traits generate extrinsic postzygotic isolation between two pine sawfly species
Oviposition preference and success depends on cross-type and host. a Proportion of females from each cross-type that laid eggs when placed within a host choice arena. Compared to other cross-types, BCL females were more willing to oviposit when placed in a host choice arena. b Proportion of egg-laying females that chose P. strobus. Preference for P. strobus declined as the proportion of N. lecontei alleles increased. c Oviposition success (proportion of females with at least one hatching egg) was significantly lower for F1 females, indicating that there is post-zygotic isolation. d Oviposition success was lower on P. strobus (white bars) than on P. banksiana (gray bars) (P < 0.05); this host-dependent reduction in fitness is consistent with extrinsic postzygotic isolation. Compared to P and BCP females, F1 and BCL females had lower oviposition success on P. strobus. However, the host-by-cross-type interaction was not significant (P > 0.05). Oviposition success data are not available for “L” females on P. strobus because no L females chose P. strobus in this experiment (“NA”). In all panels, statistical significance at P < 0.05 is indicated by differing letters (see Table 1). In (d), letters refer to oviposition success on P. strobus only (no differences were observed on P. banksiana). Cross-type abbreviations are as indicated in Fig. 2