Results of positive selection analysis for 4 genes. Each of the four graphs represents the CDS of a gene from position 1 to the stop codon (X-axis). The Y-axis is the posterior probability of each of the sites belonging to the positively selected category. The dark blue data points are sites estimated to be under positive selection. Alternative pale blue and white regions depict alternative domains in the protein, this data is taken from Swiss-Prot. The vertical red bars in each case represent functionally important sites, these are specific to each gene as follows: (a) Col1a1, (i) Cleavage site by procollagen N-endopeptidase, (ii) O-linked Gylcosylation site, (iii) Cell attachment site, (iv) Cell Attachment site, and (v) O-linked Glycosylation site. (b) PH20, (i) active site, proton donor, (ii) and (iii) are positions when mutated result in loss of activity, and (iv) N-linked Glycosylation site, (c) Prkar2a, (i) and is a Phosphothreoinine modified residue, (d) ZP2, (i), (iii) and (iv) are N-linked Glycosylation sites, and (ii) is the cleavage site.