Tuesday, January 30, 2007

Tiny Humans Found in Indonesia Are New Species

A while back, in 2003, the remains of some very small humanoid creatures were found in a cave in Indonesia. After much debate and some intrigue, it has been determined that the little "hobbits," as some have been calling them, are a new species of humans -- one that lived among us as recently as 12,000 years ago. It seems that their tiny brains had been rewired for complex functions despite their relative size deficiency.

From the BBC:

In the new study, Dean Falk, of Florida State University, and her colleagues say the remains are those of a completely separate human species: Homo floresiensis.

They have published their findings in Proceedings of the National Academy of Sciences.

The remains at the centre of the Hobbit controversy were discovered at Liang Bua, a limestone cave on the Indonesian island of Flores, in 2003.

Researchers found one near-complete skeleton, which they named LB1, along with the remains of at least eight other individuals.

The specimens were nicknamed Hobbits after the tiny creatures in JRR Tolkien's Lord of the Rings trilogy.

Computer model

The researchers believe the 1m-tall (3ft) people evolved from an unknown small-bodied, small-brained ancestor, which they think became small in stature to cope with the limited supply of food on the island.

The little humans are thought to have survived until about 12,000 years ago, when a volcanic eruption devastated the region.

Cast of Homo floresiensis skull  Image: PA
The Hobbit has forced a re-think of human evolution
LB1 possessed a brain size of around 400 cubic cm (24 cu inches) - about the same as that of a chimp.

Long arms, a sloping chin and other primitive features suggested affinities to ancient human species such as Homo habilis.

Professor Falk's analysis used the skulls of 10 normal humans, nine microcephalics, one dwarf and the Hobbit.

The brain leaves a mirror image imprinted onto the skull, from which anatomists can reconstruct its shape. The resulting brain cast is called an endocast.

Professor Falk's team scanned all 21 skulls into a computer and then created a "virtual endocast" using specialist software.

Then, they used statistical techniques to study shape differences between the brain casts and to classify them into two different groups: one microcephalic, the other normal.

Advanced tools

The dwarf's brain fell into the microcephalic category, while the Hobbit brain fell into the normal group - despite its small size.

In other ways, however, the Hobbit brain is unique, which is consistent with its attribution to a new species.

Map, BBC
Archaeologists had found sophisticated tools and evidence of a fire near the remains of the 1m-tall adult female.

"People refused to believe that someone with that small of a brain could make the tools," said Professor Falk.

She said the Hobbit brain was nothing like that of a microcephalic and was advanced in a way that is different from living humans.

A previous study of LB1's endocast revealed that large parts of the frontal lobe and other anatomical features were consistent with higher cognitive processes.

"LB1 has a highly evolved brain," said Professor Falk. "It didn't get bigger, it got rewired and reorganised, and that's very interesting."

You can read the whole article here.

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