Skip to main content
Figure 4 | BMC Evolutionary Biology

Figure 4

From: Ultraconserved coding regions outside the homeobox of mammalian Hox genes

Figure 4

Non-linear accumulation of synonymous substitutions in the Hox UCRs. A. The numbers of synonymous and nonsynonymous substitutions between two species are plotted against their divergence times, which were obtained from the TimeTree database[50]. B. Neighbor-Joining trees based on synonymous substitutions (d S ) which were computed by the pairwise deletion option (Nei and Kumar 2000). The chicken sequence was used as the outgroup. This tree shows short branches for placental mammals which diverged during the last 100 million years. Opossum and placental mammals have diverged about 145 MYA, but the branch length for opossum is shorter than that for placental mammals. This result indicates that the d S for placental mammals increased rather rapidly until their emergence. C. Neighbor-Joining tree for d N . The evolutionary pattern of this tree is similar to that of the tree for d S .

Back to article page