 Furthermore, if the group is considered conspecific, "G. gnoma" becomes the scientific name because it is older.Clear differences in the territorial calls by males are the basis for the proposed split, with birds in the high elevations of Arizona and Mexico giving a two-note call while their more northerly congeners give a repeated single-note call.Results from DNA sequence comparisons of cytochrome-b have been weak and inconclusive despite being referenced repeatedly as a justification for taxonomic splitting.