Bordewich, M.Semple, C.Steel, M.2016-05-302016-05-3020041172-8531http://hdl.handle.net/10092/12223Previous work has shown the perhaps surprising result that, for any binary phylogenetic tree T, there is a set of four characters that define T. Here we deal with the general case, where T is an arbitrary X-tree. We show that if d is the maximum degree of any vertex in T, then the minimum number of characters that identify T is log₂d (up to a small multiplicative constant).enAll Rights ReservedDiscussion / Working PapersFields of Research::49 - Mathematical sciences::4901 - Applied mathematics::490102 - Biological mathematics