THE Hobbit, the tiny human fossil found in a cave on an Indonesian island in 2003 and claimed as a new species, was a modern human whose teeth had been worked on by a dentist, possibly in the 1930s, according to a scientist whose new book is set to inflame debate.
University of Adelaide professor of biological anthropology and comparative anatomy Maciej Henneberg says in his new book, The Hobbit Trap, that a lower left molar had a filling, a claim that threatens to blow out of the water conjecture by the fossil's describers that the Hobbit is 18,000 years old.
"What I can see on the ... surface of the (tooth) is incredible," Professor Henneberg writes.
Part of the tooth surface is "occupied by a white matt substance of a colour slightly lighter than (the) enamel".
"I have a hypothetical explanation for this unusual occlusal morphology of lower left M1: a filling," Professor Henneberg says.
University of New England archeologist Mike Morwood, announcing the discovery in October 2004, said the Hobbit was 1.06m tall, weighed about 25kg and had a brain the size of a chimpanzee's.
Professor Henneberg and others have already aired doubts about the claims of Peter Brown, also of UNE, who described the fossil for science and declared it a new species, Homo floresiensis.
They said the fossil was merely a modern human, an Australoid Melanesian with the genetic disease cretinism.
Professor Brown said Professor Henneberg's claim was "complete lunacy".
"There is no factual support," Professor Brown said. "The molar tooth has no evidence of dental work of any sort and this can be demonstrated by examination of the tooth ... with photographic evidence, X-rays, CT scans."
Professor Brown accused his rival of seeking attention.
"What is annoying as a scientist is that this hasn't been through scientific peer review and (yet) it's appearing in a popular book," he said.
Asked how such an anomaly as a filled tooth could escape the attention of the fossil's discoverers, Professor Henneberg said it was understandable that in the excitement of discovery "it is easy not to notice irregularity of one tooth's surface
My father points out that hobbit man was found under six meters of cave. Hrmm, perhaps that might have something to do with it.
In any case, if this is found to be not the case (as I think is likely), creationists are still going to ignore future reports on the matter and loudly proclaim it to be yet another fault in evil scientist thinking for years to come. Just like they did with the amount of dust on the moon.
It's enough to drive me crazy. The rumor is that LB 1, the near-complete skeleton that serves as the type specimen of Homo floresiensis, may have evidence of dental work on its lower left first molar. Kate Wong wrote about it on the Scientific American blog, and Maciej Henneberg put some of the story in his new book about the Homo floresiensis saga. This means it's not just a rumor anymore: it's news.
So, does the claim have any merit? That's the part that drives me crazy. So much of this whole thing has been framed like a court of inquiry, with lawyer-like arguments about the published record. That's not how science is supposed to work.
For any other skeleton in the world, this claim would be extraordinarily simple and easy to test -- just look at the specimen, scrape at the supposed filling with a dental pick, and see what it is made of: dentin or dental cement? Or, look at a lateral radiograph.
Unfortunately, requests for access to the specimen to test the hypothesis have been denied. And no decent radiograph has emerged. In Kate Wong's article, Peter Brown has provided a CT image with a section of the left lower dentition. But the section appears insufficient to answer the question -- it has rather poor resolution (typical of medical CT scans), and cuts through the lingual cusps of the lower M1, not the buccal (cheek) cusps which appear to have been most affected by the irregularity.
I saw Maciej's pictures of the specimen and listened carefully to his line of reasoning. To be very clear, my opinion has very little value on this question: I've seen a lot of teeth, but I'm no dental anthropologist. At least one dental anthropologist I spoke to thought that the specimen was a fairly unproblematic broken tooth. Others have said it was consistent with drilling. Everybody I've talked to thinks that ultimately the question can only be settled with radiographs or direct observations.
So, I review the logic mainly to express why I would not dismiss the hypothesis of a filling in that tooth without further evidence. There are three elements:
1. The buccal enamel wall has an unusual, straight-edge discontinuity on the crown, and is raised by ca. 1.5-2 mm above the center of the tooth. The mesial enamel wall is broken away, and a whitish, flat, pitted surface characterizes most of the occlusal face, except for the enamel walls and the disto-lingual corner. This contrasts with the wear pattern on the antimere right lower M1, which has normal dentin exposure at the cusps, and the whitish color contasts with the dentin exposure of the other teeth -- although color may have no value given the uncertainty of photographs and the application of a chemical preservative to the specimen.
2. The lower molars are asymmetrically worn, with much more wear on the lower right teeth than the lower left ones. This would appear consistent with the individual chewing much more heavily on the right side than the left for some time prior to death.
3. The alveoli around many of the molars appear eroded, and a small caries appears on the left upper M1, in the region occluding with the lower left M1. The lower left P4 is absent postmortem, and its alveolus also appears eroded. These observations would all be consistent with spreading periodontal disease resulting from an initial large caries in the lower left M1.
Henneberg relays that his colleague Etty Indriati has looked into government records concerning the dental practices on Flores and other rural parts of Indonesia. According to Maciej, the government recommended a certain dental cement rather than amalgam fillings -- even though the cement does not last forever, it was much cheaper than preparing more permanent fillings and took less time to prepare. This cement does not contain metal like amalgam fillings, and might therefore escape detection in a superficial examination.
The CT image appears to show a normal-looking pulp cavity (or at least one with high contrast with surrounding material) in the lingual part of the tooth. That weighs against the idea of an extensive filling, but more detail in that region would be helpful. What is essential is to get a better assessment of the remains themselves.
I try to approach all of this stuff skeptically. The tooth is unusual, but there are ways that it might break naturally in the observed pattern. A premortem break or periodontal disease might cause asymmetrical wear by themselves. Preservative has been applied to the tooth's surface, making photographs misleading. And several skilled osteologists (including one dentist) examined the remains without noticing anything strange enough to scrape the tooth with a dental pick.
All those things weigh against the hypothesis that this tooth has had dental work. And yet, there is something unusual about it, and this hypothesis should be absolutely trivial to test. The CT scan may be enough, although with its resolution I would guess that a radiograph may be more convincing. A simple look at the specimen would be enough. Or a direct radiocarbon date -- which despite the sampling of collagen for DNA testing, was never performed.
The tooth could very well have a filling without being a fake. IIRC, the fossils were "borrowed" without permission by a group in Indonesia that claimed that it was just the fossil of a microcephalic person, and when they returned the fossils the bones were all badly damaged. They never apologized or even claimed responsibility, either. They could have broken the tooth and had a local fill it in to cover up the damage.
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SDNW4 Nation: The Refuge And, on Nova Terra, Al-Stan the Totally and Completely Honest and Legitimate Weapons Dealer and Used Starship Salesman slept on a bed made of money, with a blaster under his pillow and his sombrero pulled over his face. This is to say, he slept very well indeed.
