Scientists have found more evidence that the Indonesian "Hobbit" skeletons belong to a new species of human - and not modern pygmies.
The 3ft (one metre) tall, 30kg (65lbs) humans roamed the Indonesian island of Flores, perhaps up to 8,000 years ago.
Since the discovery, researchers have argued vehemently as to the identity of these diminutive people.
Two papers in the journal Nature now support the idea they were an entirely new species of human.
The team, which discovered the tiny remains in Liang Bua cave on Flores, contends that the population belongs to the species Homo floresiensis - separate from our own grouping Homo sapiens .
They argue that the "Hobbits" are descended from a prehistoric species of human - perhaps Homo erectus - which reached island South-East Asia more than a million years ago.
Scientists on the discovery of the 'hobbit' in 2004
Over many years, their bodies most likely evolved to be smaller in size, through a natural selection process called island dwarfing, claim the discoverers, and many other scientists.
However, some researchers argued that this could not account for the Hobbit's chimp-sized brain of almost 400 cubic cm - a third the size of the modern human brain.
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This was a puzzle, they said, because the individuals seem to have crafted complex stone tools.
They said the Hobbits were probably part of a group of modern humans with abnormally small brains.
One team led by William Jungers from Stony Brook University in the US analysed remains of the Hobbit foot.
They found that, in some ways, it is incredibly human. The big toe is aligned with the others and the joints make it possible to extend the toes as the body's full weight falls on the foot, attributes not found in great apes.
But in other respects, it is incredibly primitive. It is far longer than its modern human equivalent, and equipped with a very small big toe, long, curved lateral toes, and a weight-bearing structure that resembles that of a chimpanzee.
So unless the Flores Hobbits became more primitive over time - a rather unlikely scenario - they must have branched off the human line at an even earlier date.
In another study, Eleanor Weston and Adrian Lister of London's Natural History Museum looked at fossils of several species of ancient hippos. They then compared those found on the island of Madagascar with the mainland ancestors from which they evolved.
"It could be that H. floresiensis' skull is that of a Homo erectus that has become dwarfed from living on an island, rather than being an abnormal individual or separately-evolved species, as has been suggested," said Dr Weston, a palaeontologist at the museum.
"Looking at pygmy hippos in Madagascar, which possess exceptionally small brains for their size, suggests that the same could be true for H. floresiensis , and that (it could be) the result of being isolated on the island."
Source: http://news.bbc.co.uk/2/hi/science/nature/8036396.stm
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