In the latest issue of Nature (437), Morwood et al describe their continuing research on the skeletal remains of the "Hobbit" species of hominins on the island on Flores, Indonesia. In 2003 the researchers excavated the remains from caves in Liang Bua and defined a new, one meter tall species, that they dubbed Homo floresiensis. In 2004 they returned to the site and found more remains that they analyzed for the current Nature report. They use this latest research to bolster their theory about the identity of a representative specimen they call "LB1". The authors propose that LB1 was one of population of individuals that inhabited the island of Flores. This was an isolated species they say, not an unhealthy or compromised individual of a more common species, which is the theory preferred by competing scientists.
The authors measured the limbs and skeletal remains of the hominin and used this to determine the probable features of the species. They found that the species has unique morphological traits such as the ulna and humeral torsion. They estimate that Homo floresiensis inhabited the island as recently as 12,000 years ago and perhaps came out of Homo erectus which was known to populate the island over 800,000 years ago.
The authors theorize that the small stature is representative of "island dwarfism", a condition where the species is evolutionarily constrained, compared to off-island species. However its also possible that such an isolated species also benefits and protected from threats.
The findings are exciting, but the archaeologist and lead author Michael Morwood suggests that the researchers will be barred from returning to the caves to conduct more research. The Indonesian government has held back progress at the site by refusing to grant permits. As well, the authors report of the Nature study report; valuable specimens were destroyed by the Indonesian researchers.
Apparently Indonesia's senior palaeonanthropologist and "national icon" disagrees with the conclusions of the group and holds that the found bones are of a single individual affected by microcephaly. But another group, Falk et al, presented data in Science(Vol. 308. no. 5719, pp. 242 - 245) in April that also showed that LBI was healthy, not afflicted with microcephaly. Falk et al analyzed the brain of LB1 and concluded that the hominin had no evidence of higher cognitive processing centers but might be phylogenetically related to Homo erectus.
