The argument is Bones and Genetic Diversity. If you remember the Eoehippus, Prohippus, Hippus argument A does not always equal B. The same goes with Genetic Diversity if MCDNA is more or less static where would it be more diverse at the tip of the spear or the shaft.
Mike Morewood, the archeaologist who did the original excavation on the Hobbits, says they look more like the guys in the article below:
Stranger In A New Land (Archaeology)
"Image: JOHN GURCHE PORTRAIT OF A PIONEER With a brain half the size of a modern one and a brow reminiscent of Homo habilis, this hominid is one of the most primitive members of our genus on record. Paleoartist John Gurche reconstructed this 1.75-million-year-old explorer from a nearly complete teenage H. erectus skull and associated mandible found in Dmanisi in the Republic of Georgia. The background figures derive from two partial crania recovered at the site.
Very interesting discussion, thanks.