Scientists clash over existence of 'hobbit'

A skull from the genus 'homo floresiensis'

A spat has broken out about the scientific evidence purporting to show that a miniature species of "hobbits" lived on a remote Indonesian island about 18,000 years ago.

A team of scientists believes that the skull at the centre of the discovery is not from a metre-high member of another human species but belonged to someone with microcephaly - a congenitally small brained person.

Such allegations have been made before but this time the doubters over the hobbit - formally called Homo floresiensis - accuse other scientists of poor science and the media of hype.

The latest criticism has emerged in the American journal Science whereas the original study was published in the British journal Nature.

It is not the first time that the two publications have apparently tried to rubbish each other's articles.

When the original study about a new species of dwarfed human being was published in Nature in 2004 it was heralded - not least by the journal itself - as one of the most important discoveries in anthropology for a century.

The partial skeleton of a female was found on the island of Flores.

She stood about 3 feet tall with a small head perfectly in proportion to her body containing a brain the size of a grapefruit.

However, Science soon published doubts about the find by scientists who suspected that the skeleton belonged to a prehistoric member of our own species who just suffered from microcephaly.

If true it would mean that the find did not warrant the accolade of a new human species, and certainly not one with the miniaturised features of the so-called hobbit.

Then a study by Dean Falk of Florida State University, also published in Science, appeared to cast doubt on the microcephaly revisionists.

Professor Falk compared brains scans of Homo floresiensis with the skull of a modern microcephalic and concluded that the two had few similarities.

The latest study in Science however criticises Professor Falk's study as scientifically flawed because the scientists used a single, defective brain cast made more than 100 years ago of a 10-year-old microcephalic boy.

Professor Robert Martin of the Field Museum in Chicago, who led the study, said that the brain capacity of the skull found on Flores is just not big enough to be capable of making the sophisticated stone tools found at the cave site on Flores.

Professor Martin also criticised Professor Falk for using a poor-quality cast of the braincase of a microcephalic boy with a severe version of the condition, rather than comparing the "hobbit" to an adult with a milder form of the condition.

"This defective plaster copy of a microcephalic skull used in the study...

is inappropriate for any scientific study, especially one with a topic as demanding and high-profile as this one," Professor Martin said.

"Quite simply, it was the worst possible choice for this study.

The cranial capacity turned out to be only 260 cubic centimetres, just over half of that recorded for the [Flores] skull, and is one of the smallest I have so far found in a survey of over 100 human microcephalics," he said.

The only plausible explanation for the small size of the ancient skull found on Flores is that it belonged to a microcephalic person who had lived into adulthood.

"There has been too much media hype and too little critical scientific evaluation surrounding this discovery, and it simply unacceptable that papers should be published without providing proper details of the specimens examined," Professor Martin said.

"The principle of replicability is fundamental to good science, and it has not been respected in this case," he said.

- INDEPENDENT