sentences:  For a person, the spatiotemporal continuity of the body provides the relevant connection; from infancy to old age, the body traces a continuous path through the world and it is this path, rather than any characteristics of the individual, that connects the baby and the octogenarian.For a taxon, if characteristics are not relevant, it can only be ancestral relations that connect the Devonian " Rhyniognatha hirsti" with the modern monarch butterfly as representatives, separated by 400 million years, of the taxon Insecta.If ancestry is sufficient for the continuity of a taxon, however, then all descendants of a taxon member will also be included in the taxon, so all bona fide taxa are monophyletic; the names of paraphyletic groups do not merit formal recognition.