The toes of the 'hobbit' feet were similar
to modern human toes (pictured),
suggesting that this species walked
upright.
Image: iStockphoto

Two papers in Nature magazine this week will substantiate the view that Homo floresiensis (nicknamed the ‘Hobbit’) that lived on the Indonesian island of Flores until at least 17 000 years ago, was a distinct species -- though even stranger than anyone had realised.

Researchers from the University of Wollongong co-led in the discovery of the ‘hobbit’ five years ago and Professor Mike Morwood (Earth and Environmental Sciences) is the co-author of one of the papers appearing in this week’s Nature entitled ‘The foot of Homo floresiensis’.

Since 2004, debate has raged as to whether the diminutive and tiny-brained species of human represents a distinct species or some instance of modern humanity stricken with a form of microcephaly -- a name for a collection of syndromes in which the patient has an unusually small head.

One argument for microcephaly in Homo floresiensis is that her head was disproportionately small, even for a creature that might have undergone the dwarfing seen in creatures on islands. In the first Nature paper, Eleanor Weston and Adrian Lister have looked at this problem by analogy, through studying fossil hippopotami dwarfed after isolation on the island of Madagascar, cut off from their African ancestors.

Strikingly, Weston and Lister show that the brains of the dwarf hippos shrunk disproportionately, suggesting that the brain of Homo floresiensis might have been small simply as a result of island dwarfing rather than any kind of pathology.

In a related paper, Professor Morwood and colleagues turn from the Hobbit’s head to its feet.

The researchers (including the lead author Professor William Jungers of Stony Brook University in the United States) show that although the feet had fully adducted big toes, just as in modern humans that walk fully upright, they were much longer relative to the rest of the lower limb than in modern humans. They instead resemble the proportions seen in some apes.

Their findings raise the possibility that the ancestor of this species was not Homo erectus, as many had thought, but was another more primitive and remote hominin.

“The hobbits still remain mystifying anomalies. They are the wrong species in the wrong place at the wrong time according to conventional models for early hominin dispersal,” Professor Morwood said.