(a) Sex-ratio minimizes girls fecundity
Overall, SR/ST females produce fewer offspring than ST/ST females (Fdos,2 = 7.0, p = 0.0013), and this is significant for each SR strain (SRMyself: t = ?2.9, p = 0.0049; SRNyc: t = ?2.4, p = 0.018). However, there was not a significant difference in the effect of SR strain on female fecundity (SRMe: 159 chatrouletteprofiel ± 8.3 (mean ± s.e.), SRNyc: 174 ± 11.5; F1,1 = 3.7, p = 0.056). Across both SR strains combined, SR/ST females produced an average of 165 ± 6.7 offspring (n = 74) whereas ST/ST females produced an average of 197 ± 6.1 offspring (n = 66), a 16.3% reduction in fecundity (95% CI 0.074–0.245).
Figure 1. Female fecundity of SR carriers is reduced when compared with wild-type females. Two different SR chromosomes were assayed (SRMyself and SRNew york) in heterozygous females, and each was compared to wild-type (ST/ST) females with an otherwise similar genetic background. The dark line in the box indicates the median and the bottom and top of the box indicate the first and third quartiles, respectively. (Online version in colour.)
(b) Zero effect of intercourse-ratio to your durability
We find segregating variation for longevity, but we do not find that SR carriers show reduced survival relative to ST carriers. We assayed 2669 flies for longevity, which included female and male carriers of two different SR chromosomes and four different ST chromosomes (electronic supplementary material, table S1). SR carrier status did not contribute significantly to variation in longevity (figure 2; electronic supplementary material, figure S4; females: Wald ? 1 2 = 2.5 , p = 0.1; males: Wald ? 1 2 = 0.8 , p = 0.7), but there was a significant effect of line within chromosome type (females: Wald ? 4 2 = 24 , p = 0.0004; males: Wald ? 4 2 = 3 , p < 0.0001). Within chromosome type, there was no significant difference between the two SR strains (females: Wald ? 1 2 = 0.2 , p = 0.6; males: Wald ? 1 2 = 0.3 , p = 0.6), though there was among ST strains, which is owing to a longer lifespan of the Ny2 line when compared with the other lines (females: Wald ? 1 2 = 6 , p = 0.01; males: Wald ? 1 2 = 13 , p = 0.0004).
Figure 2. Brand new lifetime of female SR companies (SR/ST) isn’t reduced relative to wild-variety of (ST/ST) girls. Flies try split from the filter systems, including four ST strains and two SR stresses. (On line type when you look at the colour.)
(c) Ladies don’t discriminate facing mating having sex-ratio guys
We do not find evidence that virgin females discriminate against mating with SR males. First, in no-choice trials, females mated at similar rates with SRMe personally and ST males (SRMe personally: (76%) mated, ST: (82%) mated in 2 h; FET, p = 0.55). Of the pairs that copulated, the mating latency was not significantly different between SRMe and ST males (SRMe personally: 34.0 ± 2.6 min (mean ± s.e.), ST: 29.9 ± 4.5; Wilcoxon rank-sum test, Z = 1.69, p = 0.09; electronic supplementary material, figure S5). Second, we do not find evidence that females discriminate against mating with SR males in situations with the extensive male–male competition. In our cage experiments, none of the three tester male genotypes (ST, SRMyself and SRNew york) showed a consistent difference from 50 : 50 random mating against the dark males (ST: ? 1 MH 2 = 0.18 , p = 0.7; SRMe personally: ? 1 MH 2 = 0.01 , p = 0.9; SRNY: ? 1 MH 2 = 1.5 , p = 0.2; electronic supplementary material, figure S6).