Character convergence occurs when two species on different evolutionary trajectories evolve to possess the same character. For an example, consider the division of dinosaurs into the orders Saurischia (lizard-hipped) and Ornithischia (bird-hipped). Although birds evolved from dinosaurs, they derive from a suborder of saurischians, not ornithischians. The result is that
Converging characters (in addition to reversion) can greatly complicate character-based phylogeny, calling for more rigorous phylogenetic methods.
