Figure 1.

Neighbor-joining tree of the GLI family members. The percentage of replicate trees in which the associated taxa clustered together in the bootstrap test (1000 replicates) are shown next to the branches. The tree is drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. All positions containing gaps and missing data were eliminated from the dataset. Black arrowheads show duplication events that occurred before the tetrapod-fish divergence whereas the open arrows indicate lineage specific duplications. Scale bar shows substitutions per site.