Stone tools used to back 'Hobbit' theory

Scientists have produced further evidence to support the idea that a miniature species of human, nicknamed "the hobbit", lived on a remote Indonesian island until becoming extinct more than 10,000 years ago.

The latest study suggests the one metre-high creatures could make fairly sophisticated stone tools despite having brains no bigger than grapefruits.

Specialists are divided over ancient bones found in a cave on the island of Flores which seem to suggest that another human species lived alongside Homo sapiens as recently as 12,000 years ago.

Skeletal remains of the creature - formally named Homo floresiensis - suggested that adults walked upright, were about 3ft tall and, unlike modern-day pygmies, had a small head in perfect proportion to the rest of the body.

The most important specimen recovered from the floor of the cave at Liang Bua in Flores was of a complete skull, although the bones of about eight other individuals have also been dug out and analysed.

The skull is so small that it can fit neatly into the palm of a hand. It has a cranial capacity of just 400 cubic centimetres - about two or three times smaller than the brain of modern humans.

Sceptics have argued that a creature with such a small brain could not have possibly made the fine stone tools found at the same level in the cave sediments - and presumably buried at the same time that H. floresiensis had lived there.

Proponents of the hobbit concept have suggested that the creature used the tools to hunt and butcher the miniature elephants, giant komodo dragons and oversized rats, whose remains were also found alongside the human bones.

However, last month sceptics poured scorn on the idea, saying that the skull belonged to a person with microcephaly, a congenital disease resulting in exceptionally small skulls and stunted growth.

James Phillips, professor of anthropology at the University of Illinois at Chicago, said that it was wrong to suggest that the stone tools could have been made by earlier species of humans, such as Homo erectus, a creature that evolved more than 1.8 million years ago and predated modern humans by many hundreds of thousands of years.

"These tools are so advanced that there is no way they were made by anyone other than Homo sapiens," Professor Phillips said.

Now, however, another team of stone-tool experts has cast doubt on this judgement, saying that similar stone tools have been uncovered on the island that clearly predate the arrival of modern Homo sapiens.

Adam Brumm of the Australian National University in Canberra and his colleagues report in the journal Nature that they have found hundreds of almost identical stone tools at a site called Mata Menge just 30 miles away from the Liang Bua cave. They say the tools are between 700,000 and 840,000 years old - too old to have been made by Homo sapiens - and that the production techniques are practically identical to that used at Liang Bua 18,000 years ago.

"The Mata Menga evidence negates claims that stone artefacts associated with H. floresiensis are so complex that they must have been made by modern humans," the scientists say. "Despite being separated by 30 miles and at least 700,000 years, there are remarkable similarities between the stone artefact assemblage from Mata Menge and that found with H. floresiensis at Liang Bua."

No human remains have yet been found at Mata Menge so it is not clear who made the stone tools found at the site, but the scientists point to the only known possibility - Homo erectus. They suggest H. floresiensis could therefore be a direct descendent of H. erectus and that the knowledge of how to make the stone tools was passed down the generations to descendants who had evolved into a miniature form.

"Pronouncements that H. floresiensis lacked the brain size necessary to make stone artefacts are therefore based on preconceptions rather than evidence," the researchers say.

Bones of contention

PILTDOWN MAN: The skull and stone tools of an apparent ape-man were dug from gravel deposits in Piltdown, East Sussex between 1911 and 1915 and were soon declared the "missing link" between apes and humans. In 1953, a study showed that the artefacts were elaborate forgeries, a mixture of human and primate bones. One of biggest scientific discoveries in human origins was declared an embarrassing hoax.

TOUMAI MAN: French scientists discovered a six to seven million-year-old skull in northern Chad in 2002. Formally named Sahelanthropus tchadensis, the creature became the oldest known member of the human family. Other scientists later dismissed it as belonging to an extinct species of ape who did not habitually walk on two legs, a distinguishing characteristic of the human family. The journal Science, however, voted the discovery its Breakthrough of the Year.

DMANISI MAN: Scientists discovered several skulls of early humans dating to about 1.8 million years ago near Dmanisi in Georgia. The small-brained creatures belonged to a species called Homo erectus and reignited the debate over early human migrations. One theory is that Homo erectus died out and was replaced by Homo sapiens, another theory is that the two species interbred and modern humans evolved not solely in Africa but in several regions of the world.

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