FIGURE 2.

Phylogenetic relationship between early-diverging Chordates and Actinopterygians. Illustrative cladogram showing the main phylogenetic relationship between clades with available information about MCH. Several clades have been omitted for clarity, and the cladogram is not meant to represent the absolute order of relationship between these groups, but rather the most probable organization based on current molecular data and information about the MCH system. The relative position of two pmch duplication events are indicated in green, and the resulting genes are indicated under each clade name. The ubiquitous vertebrate pmch and its homologs are indicated in red, while the teleost-specific pmchb is indicated in blue. The duplicated copies originated in the salmonid lineage are indicated in different shades of red and blue. To facilitate the reading of this review, relevant clades are indicated alongside their rank on the right side of the cladogram, encompassing the clades to the left of each black line. ^∗ Unranked clades.