Fig. 3.

Violin plots showing estimated sexual Isolation Index (eSII) in multiple choice assays between D. paulistorum wild type (wt), Wolbachia-knockdown (kd), axenic (et), and penicillin/streptomycin-treated (ps) flies. (a, b) Intra-semispecific mate choice assays with pool lines. Wild type (wt) flies (control, in purple) or knockdown (kd) flies (in orange) were assayed at generations F₄, F₅, F₁₃, against wt flies, for A28 and O11. (c, d) Intra-semispecific mate choice assays with isofemale lines. wt vs. wt (purple), and kd vs. kd (pink) mating choice assays were performed between different isofemale lines, respectively at generation F₁₀ and F₈. e Intra-semispecific assays between wt and gut-flora-restored flies (gfr) performed at generation F₁₀ for A28 and O11. f Intra-semispecific assays between wt and ethanol-washed wt flies (et) performed at generation F₂ for A28 and O11. g Intra-semispecific assays between wt and penicillin/streptomycin-treated flies (ps), performed at generation F₃ for the A28 and O11. The last assay (yellow) is an additional inter-semispecific assay between wt and ps flies. For all assays, the model-estimated SII was used on either individual replicates (dots), or considering the 5 replicates (horizontal bars). Asterisks denote assays for which the likelihood ratio test (LRT) is highly significant (p values < 10⁻⁴), the null model being random mating (SII = 0). All the p values are reported in Tables S2–S4. (Color figure online)