The World Today - Researchers verify Flores hobbit as new species of human being

[Nadvojvoda Janez Kranjski]

The World Today - Researchers verify Flores hobbit as new species of human being

[ http://www.abc.net.au/worldtoday/con...5/s1316120.htm]

The World Today - Friday, 4 March , 2005 12:18:00

Reporter: Michael Vincent

ELEANOR HALL: It was one of the biggest scientific discoveries ever – the uncovering on the Indonesian island of Flores of a new species of human, quaintly dubbed "the hobbit".

But since Australian scientists announced the find with a research article in Nature in October last year, a controversy has raged about the true nature of the remains, with critics saying the bones are only of a diseased human, not a new relative at all.

But today an independent team of international scientists has published its analysis in the journal Science, saying "the hobbit" is indeed a new species of human being.

Michael Vincent reports.

MICHAEL VINCENT: The Australian scientists who found the so-called hobbit have been nervously waiting today's announcement. Their scientific reputations have been on the line ever since they claimed to have found a new species of human being.

Dr Dean Falk from Florida State University led the team of international experts who examined the hobbit's skull. She used cat-scans to generate a three-dimensional image of the hobbit's brain and compared it to a female human, homo erectus and chimpanzee.

DEAN FALK: When I began researching the brain evolution, I was very sceptical, I have to tell you that, and I came around to realising that they had to struggle with it, that what the brain tells me is they got it right.

MICHAEL VINCENT: And that's a relief to Australian team member Dr Richard Roberts from the University of Wollongong, who dated the original find. He says today's published evidence proves the hobbit is not a deformed human or someone suffering from a brain disorder known as microcephaly.

RICHARD ROBERTS: I think it's a sensational find, and that there are two major conclusions, the first of which is that the brain of the hobbit is completely unlike that of a microcephalic person, this is a deformed person that some people have been claiming that's all the hobbit was, and it's also completely unlike that of a pygmy, a modern pygmy.

So it's certainly not that of a modern human who's either very small or has got a condition called microcephaly. But it does have features that are incredibly interesting, because they've got a very well developed frontal lobe.

MICHAEL VINCENT: But the controversy doesn't end here. Critics of this today's published investigation claim Dr Falk and her team didn't compare apples with apples, that is they didn't use a skull with the correct example of the brain disorder known as microcephaly.

It's a claim Dr Falk rejects.

DEAN FALK: What we say is this was not a paper which was doing the be-all and end-all of secondary microcephaly, which is a very nebulous catch-all term, by the way, and really the burden of proof on those people who say oh it's a microcephalic is hey, go out there, do a scientific study, and now we offer you some new information with which to form a testable hypothesis.

MICHAEL VINCENT: And Dr Richard Roberts also issues the same challenge to his critics.

RICHARD ROBERTS: It's really time to sort of put up or shut up in that regard. Now with their backs to the wall I think it's time for them to put everything they think down on paper, and we can decide whether it actually stands up scientifically or not.

MICHAEL VINCENT: Why is it so important to publish in a scientific journal if you're an academic?

RICHARD ROBERTS: Well, it's easier to talk to the media, and you can sort of waft around and change your opinion fairly freely, but in the scientific literature, once you've put your position down, people can grill it, they can look at it extensively, evaluate what you've said and say well this doesn't make sense, or this is inconsistent with known evidence.

It's really like going into a boxing fight. There's lots of, you know, 'I'm the greatest, I'm the greatest' at the outset, but the bottom line is you want to get into the ring and show what you're actually made of. And that's the way it is with science.

You can talk about it, but then you've really got to put your meat down in the paper and say this is really what we believe to be the case, and at the present time they haven't done that at all.

MICHAEL VINCENT: Dr Roberts is still open to the possibility his team may be wrong. There is one last challenge for the scientists who found the hobbit to prove its origins as conclusively as possible – DNA.

RICHARD ROBERTS: What was the ancient DNA like of this type of extinct human? If it turns out to be modern human DNA, that would be an absolutely staggering finding, because you have to say well, how can that be so, how can we have modern DNA look completely unlike us with a brain completely unlike ours?

That would be a serious fly in the ointment, so we do want to do DNA analysis of our own on the skeletal material. That will be the final nail in the coffin for the microcephaly argument.

ELEANOR HALL: Dr Richard Roberts from the University of Wollongong speaking to Michael Vincent.

[Nadvojvoda Janez Kranjski]

Was this small brain able to think big?
JAY INGRAM

Remember Flores man (actually a woman)? Flores "person" is a skeleton that was found last year on the island of Flores in Indonesia. It was a sensational discovery then, but has been made even more exciting this week with revelations about his brain.This new species appeared to live as recently as 13,000 years ago and stood only about a metre tall. There hadn't been a hominid that small on the Earth for millions of years. But despite its small brain, it appeared to have used stone tools and controlled fire. In other words, small-brained or not, it was smart.The discovery raised all kinds of questions. Where did this creature come from? The only sensible idea seemed to be that it had descended from Homo erectus, an ancestor of ours practically as big as we are. The theory was that some Homo erectus individuals migrated to the island, and over time shrank due to the well-known effect that tends to reduce the size of mammals that are island-bound.But if that was the case, how was Flores man able to retain its intelligence in the face of a dramatic reduction in brain size? Does that mean it's possible to stay smart with less brain?That wasn't the only controversy. Teuku Jacob, the grand old man of Indonesian archeology, examined the skull and immediately proclaimed it to be a fully modern human suffering from microcephaly, a disorder of development that leaves the skull, and the brain within, shrunken and deformed. According to Jacob, it was anything but a new species.The report, published Thursday, addresses this very criticism and concludes that Jacob was wrong, that Flores man was not a microcephalic and does indeed bear a strong resemblance to Homo erectus, but with some surprising differences.Dr. Dean Falk of Florida State University came to those conclusions by analyzing virtual endocasts of a variety of skulls, including a microcephalic, Homo erectus, modern human and Flores. Endocasts are usually made by pouring liquid rubber into a skull. When the rubber hardens, it bears the imprint of marks on the inside of the skull that were left there by the brain. The endocast is a surrogate for the original brain.In this case, the Flores skull was so fragile that the researchers were forced to resort to a virtual endocast made by scanning the inside of the skull. Falk says the resulting "brain" was one of the most surprising she has ever seen (see image at right).First, and most important, it is radically different from the microcephalic specimen she compared it to. This isn't a conclusive denial of Jacob's claim that Flores is nothing new — one skull isn't enough — but Flores and the microcephalic are so different it's hard to imagine how they could be one and the same.What's more interesting is the comparison of Flores with Homo erectus, the species that was suggested to have been its ancestor. The two brains are worlds apart in size: Flores's brain is less than half the volume of the Homo erectus brain (and less than a third as big as a modern human brain). Even so, Falk was shocked to discover that this tiny brain had very well developed frontal lobes, parts of the brain that are, at least in us, associated with complex thinking and planning.So, although the Flores brain was small, even by the standards of hundreds of thousands of years ago, it looks modern. Not as modern as our brains, but more advanced in some ways than Homo erectus, the species from which it is supposed to have evolved.But did it? In the light of these new insights into the brain, Falk and the Australian archeologists who discovered Flores are stressing that there is another possibility: Flores man and Homo erectus might both have descended from an as-yet-undiscovered small-brained, small- bodied ancestor. That creature's descendants would have split into the two species, one small, one tall. There's talk of searching on other Indonesian islands for the remains of that hypothetical ancestor, or for more Flores man. It's an exciting time, partly because the human family tree is branching out wildly in all directions, partly because these new fossils are raising new questions about brain size and intelligence. How smart can a small brain be?

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