Figure 4
From: Onychophoran Hox genes and the evolution of arthropod Hox gene expression
Summary of phylogenetic signals based on onychophoran and arthropod Hox gene expression. Conserved and diverged characters are plotted on the nowadays best-supported arthropod phylogeny. Onychophora, and onychophoran data, serve as outgroup. Dark red boxes denote events during arthropod Hox gene evolution. Light red boxes denote unresolved character-state; in these cases the character-state cannot be determined ancestral or derived because outgroup data for a clade Onychophora + Arthropoda are not available.