It is generally believed that the Arthropoda constitute a natural, monophyletic group.
On the question as to whether descent was monophyletic or polyphyletic Darwin expressed no dogmatic opinion.
The problem of the monophyletic or polyphyletic origin of the human race has also been much discussed.
monophyletic mon·o·phy·let·ic (mŏn'ō-fī-lět'ĭk)
Descended or derived from one original stock or source.
Of or being the theory that all blood cells are derived from one common stem cell.
Relating to a taxonomic group that contains all the descendants of a single common ancestor. All clades, such as birds and placental mammals, are monophyletic. Compare paraphyletic, polyphyletic.