By focusing on gene expression, we relax the implicit assumption of previous studies that a majority of adaptive evolution occurs via changes in amino acid sequences. Furthermore, all of the resampled time point distributions heavily overlap with one another indicating that higher expression divergence on the X is not driven solely by one or a subset of time points.
Theory suggests that mutations could have fitness consequences that are non-linear even if they have additive phenotypic effects .
Beneficial mutations with additive effects in heterozygotes are selectively equivalent on the X chromosome and on the autosomes, and would therefore be expected to evolve at similar rates across the chromosomes, whereas beneficial mutations that are dominant are expected to evolve faster on the autosomes .
Wild-type flies show an activity rhythm with a frequency of about a day 24 hours. A high-level connectome, at the level of brain compartments and interconnecting tracts of neurons, exists for the full fly brain. Proc Biol Sci 91—
Polygenic Risk Scores. Mean divergence is plotted for genes belonging to each percentile of a particular chromosome's divergence distribution separately for 2L, 2R, etc relative to genes in the same percentile of the divergence distribution of the the rest of the genome all other chromosomes.
In the absence of dosage compensation, however, theory suggests that beneficial mutations must be more recessive for the X to evolve faster provided that the weaker expression in males results in a correspondingly weaker beneficial selection coefficient  — this is because dosage compensation equalises the expression of genes expressed on the X in males and females, and is therefore assumed to autosomes vs sex chromosomes images in Greater Manchester equalise their selection coefficients.
Charlesworth D. Thank you for your feedback. Divergence of gene expression across chromosomes in both adult males and females for genes with male-biased expression in either D. The volume is available for sparse tracing of selected circuits.
Pearson residual shading is used to depict deviations from null expectations — blue excess and red paucity colours indicate deviations from the expectation under the null hypothesis that the two variables, mutational heritability and chromosome, are independent . Vicoso B, Haddrill PR, Charlesworth B A multispecies approach for comparing sequence evolution of x-linked and autosomal sites in drosophila.
Mutations in trans -acting factors are more likely to be pleiotropic, and so should have less scope to influence adaptive evolution than the more modular effects of mutations in cis -regulatory regions  ,  — . Katz; Donald J.