Best foot forward: Assembly of the foot of the type specimens (LB1) of Homo floresiensis.
Credit: Djuna Ivereigh/ARKENAS.
Companion studies, published online in the Journal of Human Evolution, bolster this theory by looking at other parts of the anatomy, and conjecture that these more ancient forebears may be the still poorly understood Homo habilis. Either way, their status as a separate species would be confirmed.
That still leaves questions about the curiously tiny head of the hobbit – which had a chimp-sized brain of around 400 cm3, a third the size of a modern human brain – seemingly too small even for a legitimate dwarf species.
Hippo brains
In a second paper published this week in Nature, Eleanor Weston and Adrian Lister, palaeontologists at the Natural History Museum in London, showed that a model of brain size reduction in hippos might be used to help explain the very small brain size of H. floresiensis.
Weston's team compared the brain sizes of extinct Madagascan dwarf hippos to that of a modern common hippopotamus, scaled-down by body size. Dwarf hippo brains were found to be up to 30% smaller than their scaled counterparts.
Similarly, when they scaled a modern human brain down to the size of H. floresiensis and then reduced it by a further 30%, they found a volume very similar to that of the H. floresiensis fossil. "This provides evidence for a possible evolutionary mechanism that could explain brain size reduction in humans," said Weston.
Looking at all the evidence, Peter Brown, a palaeoanthropologist at the University of New England, in Armidale, Australia, thinks we may be looking at a new species that last shared a common ancestor with modern humans two million years ago.
"Walked like ducks"
"Evolution is full of experiments – some are successful and some aren't. The Flores skeletons have many primitive features, including the bones of the wrist, the anatomy of the ear region, and the ratio of the arms to the legs. These are features found in our earliest ancestors, the Australopithecines and are not going to be produced by dwarfing," he said.
Maciej Henneberg, an anatomist from the University of Adelaide in South Australia, and proponent of the disease theory of the hobbit, isn't convinced, however. He points out that a human with these proportions doesn't make evolutionary sense – 'hobbits' would have been poor runners and clumsy hunters. "They would have walked like ducks," he quipped.
Henneberg also questioned the comparison with hippos. "It is very difficult to make a parallel between dwarfing of a water-dwelling herbivore and an omnivore which lives on land," he said.
With AFP.
Email feature not working
This is what it's sending.
Subject:
%name has forwarded a page to you from %site
Body:
[broken image]
%name has forwarded a page to you from %site
Message from Sender.........
Regards,
Mauro
so why Homo?
Surely all this evidence, which backs up the original cranial and dental comparisons, implies that the Hobbit should not have been called Homo floresiensis, but rather Australopithecus floresiensis, or some other genus name?
Homo?
The cranial features are consistant with being in the Homo genus, but the bones of the wrist, and now the foot, indicate a more primitive hominid. The collection of featuers are different from any previous finds, so don't know if this is a good fit for Australopithicus either.
In having such an odd combination of features it is sort of like Piltdown Man - a discovery in England that later proved to be a hoax.