Mark Worden is a man of unknown species.
Description[]
Mark Worden performed "additional research & portraiture" based on genealogical work by Carl Barks, culminating on the creation of a version of Donald Duck's family tree.
Behind the scenes[]
Mark Worden mentions himself (as "M. Worden") when giving the in-universe justification of his Duck Family Tree, claiming that he and Carl Barks were merely in-universe genealogists.