Fig. 3.

Distributions of codon bias as measured by FOP of all 1:1 orthologs and Y-linked genes separated by chromosome arm for D. ananassae (ana), D. erecta (ere), D. grimshawi (gri), D. melanogaster (mel), D. mojavensis (moj), D. pseudoobscura (pse), D. virilis (vir), D. willistoni (wil) and D. yakuba (yak). Median values are overlaid in red. Note that for D. pseudoobscura, “Y”-linked genes are those genes that have some history of Y-linkage in this species but are not currently Y-linked (ARY, kl-2, kl-3, ORY, Ppr-Y, and PRY).