Positive Selection and the Evolution of izumo Genes in Mammals

Figure 1

Molecular phylogeny of the izumo gene family emphasizing the formation of independent clades. n is the number of species included in each gene clade. The evolutionary history was inferred by using Maximum Likelihood and the JTT+G+F substitution model. The tree is drawn to scale, with branch lengths measured as the number of amino acid substitutions per site. The reliability of the tree branching was assessed using 1,000 replicate bootstraps. Bootstrap values lower than 50 are not shown.