Rethinking Pleijel's (1995) characters under a hierarchical point of view

Abstract

In 1995, Pleijel raised an issue on the coding of complex (multistate) characters: to find a unique coding approach satisfying both informational and semantical criteria. Following Pleijels work, this study aims to propose a new answer to this problematic. We proposed here to use hierarchical characters instead of classical partitional ones as hierarchy allows to deal effectively with the different uncertainties met by phylogeneticists since the beginning of phylogenetic data matrices: missing data, inapplicable data and polymorphism. We translated all previous proposed approaches into hierarchical ones and add three new approaches, only coded using hierarchy. Using phylogenetic and show with different metric how one of these new approaches displaces the other ones. The results from this study then supports the idea than phylogenetic characters should be coded using only hierarchies, as they offer a better management of uncertainties and propose new approaches more informative.