Frequency distribution of fecundity for <i>D. simulans</i> and introgression (IG) strains.

<p>Fecundity was measured as the total number of progeny produced by groups of five females (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061575#s2" target="_blank">Materials and Methods</a>). <i>D. simulans</i> fecundity is shown as black bars.</p

Mean relative gene expression of each introgression strain as well as sterile F1 male hybrids.

<p>Mean relative gene expression estimated as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061575#pone-0061575-g002" target="_blank">figure 2</a>, and associated errors, are shown using <i>RpL32</i> (solid symbols) and <i>RpS18</i> (open symbols) as reference genes for <i>bam</i> (A), <i>sa</i> (B) and <i>Mst98Ca</i> (C). The F1 sterile male hybrid mean expression is shown as diamonds, while IG strains data are separately shown for X (circles), second (triangles) and third (squares) chromosome introgressions and arranged along the X-axis in order of decreasing severity of down regulation.</p

Creation of chromosome introgression (IG) strains.

<p>Black bars are used for <i>D. mauritiana</i> chromosomes and non-black for <i>D. simulans</i>.</p

Differences in mean relative gene expression among genes (A) and chromosomes (B).

<p>Relative gene expression is shown as log₂ deviations from <i>D. simulans</i> and using <i>RpL32</i> (grey bars) and <i>RpS18</i> (white bars) as housekeeping reference genes (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061575#s2" target="_blank">Materials and Methods</a>). A) Mean gene expression averaged across all introgression strains and B) mean expression per site of chromosome introgression. Error bars are 95% confidence intervals.</p

Primers used in this study.

<p>Primer sequences are in 5′–3′ direction.</p><p>Exon splice = At least one of the primers spans over two exons. Intron span = primers flank an intron. None = primers do not splice an exon and they do not flank an intron.</p

Study findings.

<p>Study findings.</p

Summary of the search selection process.

<p>Summary of the search selection process.</p

Risk of bias within studies.

<p>Risk of bias within studies.</p

Study inclusion criteria.

<p>Study inclusion criteria.</p