Figure 4From: Accelerated evolution of 3'avian FOXE1 genes, and thyroid and feather specific expression of chicken FoxE1Tree topology and the models used for the likelihood-ratio tests. The numbers on the tree branches represent the mean number of substitutions per codon along the branch as estimated by the program Mega4. Branches B (common ancestor of birds) and Gl (common ancestor of Galliformes) were the lineages of the analysis in free branch models.Back to article page