So now we have a flood of potentially revolutionary information regarding Homo floresiensis and its implied lineage and a wealth of things to consider. I will try to summarize on what I think some of these things are.
At the Mata Menge site, Dr. Morwood tells us of artefacts dating back to beyond 700k and 840k to 880,000 years ago. He also tells us of stone artefacts in a sandstone layer about 20 metres stratigraphically lower than Mata Menge that have yet to be dated. We therefore have data telling us that we can reasonably surmise that we may be looking at hominin inhabitation of Flores going back to a million years. As Dr. Morwood pointed out, these artefacts most closely resemble the floresiensis artefacts at Liang Bua and the "Developed Olduwan" assemblages of Africa dating back to before 1.5 million years ago. It no longer seems likely that we can look to east Asian Homo erectus as the progenitors of the hobbits on Flores. In Dr. Morwood's own words:
"There is a growing consensus amongst people studying the actual remains that the ancestor lineage of Homo floresiensis in East Asia predates the arrival of H. erectus, perhaps by a considerable margin, and that they arrived on the island as a small-brained, short hominin species with primitive body proportions, etc."
So who or what were these Soa Basin knappers that Morwood speaks of?
Morwood explains:
"Many of the traits of H. floresiensis are more similar to australopithecines than they are to other early hominins. For instance, they comprise the only species known outside Africa with the primitive body proportions. Aspects of the brain, stature, jaw, premolars, pelvis, and feet have similar implications. But a H. habilis-like ancestor is still a possibility."
In the search for the hobbit's true ancestors one of the main hypotheses to come forward is that advanced by Debbie Argue of the Australian National University’s School of Archaeology and Anthropology, who's study I briefly mentioned earlier. Argue has found that H. floresiensis had long arms in proportion to its legs, and is close to the primitive arm-to-leg ratio of the gracile australopithecine, Australopithecus garhi. Here are some links to information on her cladistic analysis of Homo floresiensis:
http://anthropology.net/2008/06/20/...gues-cladistic-analysis-of-homo-floresiensis/
http://www.australiannews.net/story/371309
A. garhi is a gracile Australopithecine that lived between 2-3 mya during a period where there are very few fossil records. Garhi was more advanced than any other Australopithecine and at one time thought to be the final link between the Australopithecus and Homo genus. However, that position is now in question and it has been speculated that garhi was a competitor species to the Homo ancestor. Stone tool artefacts resembling Olduwan technology have been discovered with A. garhi dating to 2.5 and 2.6 mya.
Here is wiki's A. garhi entry:
http://en.wikipedia.org/wiki/Australopithecus_garhi
It seems that it would imply that garhi or a descendant moved out of Africa around 2.25 mya at a time when the first Homo species were emerging in Africa. The Dmanisi small-brained, small-bodied hominins with similarities to the hobbits date to half a million years later and are thought to be the earliest out of Africa. It would also imply that the hobbits ancestors arrived in east Asia at least half a million years before Homo erectus as Morwood suspected.
Argue's work suggests that H. floresiensis' stature is not the result of strong insular dwarfism. It's important to remember that while the stegadons were small, they didn't come to Flores as big elephant-type creatures and then shrink. The stegadons on Flores have been shown to have down-sized 30% over time on Flores which Morwood thinks might serve as a guideline for looking at the extent of potential dwarfing in the hobbits. We know that LB1, the type specimen for floresiensis had cranial capacity of 417cc while A. garhi had a capacity of 450cc. With the intricate folding shown in floresiensis' brain by internal scanning we can surmise that possibly some minor down-sizing did occur along with unique adaptations in the brain. This would ensure for the retaining of the intelligence that allowed the hobbits to employ behaviour patterns and technology needed for successful survival against the rigours of Flores.
What would greatly help in gaining a clearer picture of Homo floresiensis' lineage are the following:
- DNA retrieved from floresiensis teeth. As Morwood puts it:
"And if DNA was found it would not only confirm the species-status of hobbit, but would also allow the "split" between their lineage and ours to be dated, and provide evidence for the hominin genotype at that time depth—2 to 2.5 million years ago would be my estimate."
- Another skull from Liang Bua to allow further cranial measurments and end doubts regarding microcephaly and other pathologies.
- Hominin remains from Mata Menge to establish the identity of the Soa Basin knappers.
- An intermediate site on Flores, preferably around 300,000 years, to establish the effects of the Flores environment on the endemic hominin population.
What I can confidently say now is that the mystery started on Flores at Mata Menge and Liang Bua with Homo Floresiensis may reach farther and become more profound than anyone could ever have imagined.
Zoomable satellite photo of Flores and other Sunda islands.
. Then 200 sounds as a very low number. Moreover, the links you provided, and wiki, suggest that Flores has a fertile soil, due to the volcanic ashes, and in prehistoric times had abundant (forest) vegetation - before modern man deforested it.