When a team of Indonesian and Australian palaeontologists discovered a nearly complete but very strange 18,000‐year‐old human skeleton in an Indonesian cave in 2003, the find provoked questions about modern human origins. Do these ancient bones belong to a new human species? Are they, as many have claimed, the most important find in hominid palaeontology for decades? Or is this creature—indelibly christened ‘the Hobbit’ because it is so tiny—simply one of an isolated people who suffered from a deforming malady? The huge stakes in this competitive, caustic debate can be summed up succinctly: money and fame. But Hobbit investigations may eventually have less impact on the study of human evolution than they do on the standing of palaeoanthropology, and on the continuing crusade against the Darwinian account of how life on Earth evolved.
…Hobbit investigations may eventually have less impact on the study of human evolution than they do on the standing of palaeoanthropology…
The bizarre story so far: In 2003, a joint Indonesian–Australian team, digging in Liang Bua cave on the Indonesian island of Flores, found hominid bones and a nearly complete skeleton. The skeleton, designated LB1, was childishly tiny, but tooth wear showed the hominid to have been aged about 30 at death. In 2004 at the same site, the team uncovered another mandible and more bones and bone fragments, from a total of eight individuals. Dates inferred indirectly from materials around the finds range from about 94,000 to 12,000 years ago. This suggests that the hominids lived there for a very long time, overlapping with fully modern Homo sapiens on Flores for many thousands of years. LB1 was declared female and dated at 18,000 years old.
In 2004, Nature published the 2003 discovery to unprecedented commotion (Brown et al, 2004; Morwood et al, 2004). The authors declared that the bones were those of unique, unknown humans, which the scientists named Homo floresiensis, and were possibly descended from Homo erectus. Nearby tools resembled those from early H. sapiens in Europe. H. floresiensis's small size, about 1 m, was attributed to island dwarfing, a phenomenon believed to occur when being big is a disadvantage because predators are absent and resources scarce. It seemed that they hunted an elephant that was similarly dwarfed. And—most astonishing of all—their complex culture was carried out with a brain estimated to be between 380 and 417 cm3 in size, which is smaller than the brain of an average chimp. This had scientists busily speculating that brain organization, rather than sheer size, must be even more central to human behaviour than previously believed.
The fragile bones—never fossilized and originally described as being like wet blotting paper—were kept at the Indonesian Centre for Archaeology in Jakarta, but were moved in November 2004 to the laboratory of Teuku Jacob, an eminent Indonesian palaeoanthropologist. The circumstances surrounding the transfer remain murky. Jacob is not a member of the original discovery team, but is in charge of a large collection of H. erectus fossils at Gadjah Mada University in Yogyakarta, about 275 miles from Jakarta. He says the move was at the request of Radien Soejono, a dig leader and one of the Hobbit paper's authors, who works at the Centre. It was normal, Jacob noted, for him to receive Indonesian bone finds while other artefacts remained at the Centre. The bones, he said, would be studied in his lab. Indonesian researchers not connected with the find carried out some of this work, but nothing has yet been published. Jacob also allowed Australian, US and German researchers to study the bones without asking permission from the discovery team members.
DNA studies, which could establish whether LB1 is H. sapiens or something completely different, are not likely to occur in the near future
Team members and other scientists were enraged over the moving of the bones. “From comments I have received or heard, most scientists are very concerned about what has happened to the material, and are hoping it can be returned as soon as possible to be studied by the original team. What has happened threatens all further research on the Flores site,” said Chris Stringer of London's Natural History Museum. “The people who originally excavated and studied the material should be the ones taking forward work such as DNA testing, not someone who had taken over the finds from them.”
The dispute was further fuelled when Jacob charged that the discovery team had bungled their analysis. LB1 and company, he said, were not a new species of Homo, they were simply short people; LB1 was male, not female, and had prehistoric microcephaly. Microcephaly is a nonspecific term for an abnormally small brain and skull; the condition has many variations and scores of known causes, both genetic and environmental. The main Nature paper had actually raised and dismissed some of these possibilities. This paper argued that LB1's skeletal features are not consistent with dwarfism, including microcephalic dwarfism, nor are her stature and brain size similar to pygmy populations. And although some features, such as her canine teeth, are sapiens‐like, her skeleton resembles australopiths, the authors of the paper noted. Palaeoanthropologists have never before seen anything like this assortment of modern traits mixed up with hominid skeletal anatomy that dates back millions of years.
In the meantime, Jacob's diagnosis has been backed up by a handful of other palaeoanthropologists, including some visitors who have seen the bones. The discovery team—and many others—think this is nonsense. Team leader Michael Morwood of the University of New England (Armidale, NSW, Australia) declared that “the vast majority” agree with their original assessment. “We don't have any credible critics. All we have is opinion in unreviewed publications.”
After months of negotiation, most of the bones were returned to Jakarta in February, 2005. Discovery team members were delighted to once again have access to the second mandible and other bones from the 2004 season, but there soon came another shock. The bones had been seriously damaged: the pelvis had been smashed, the second mandible had been broken and unskilfully repaired, and LB1's skull had been mutilated by latex moulding; Science published photos of the damaged pelvis (Culotta, 2005). Morwood charged that bones with australopithecine traits had been almost destroyed. “The condition of some finds is absolutely appalling,” he said. “This is not the action of responsible scientists.” Jacob acknowledged taking moulds, but says he has photos showing that the bones were in perfect condition when they left his care.
Meanwhile, a study of LB1's brain, based on skull endocasts made before the bones were moved, was also published (Falk et al, 2005). First author Dean Falk of Florida State University (Tallahassee, USA) concluded that the brain was unique and somewhat erectus‐like, but had advanced features, such as an enlarged prefrontal cortex, that hinted at respectable cognitive capacity. Comparing it with a single skull from a microcephalic, the group also concluded that LB1's brain was not altered by disease. Falk is now studying additional microcephalic endocasts for comparison. “This was just a thrill,” she said. “We said to them, ‘We stand ready. If you find any more skulls, we'd love to analyze them!'”
Ralph Holloway of Columbia University (New York, NY, USA), an eminent endocast expert, has studied an endocast he made from the original CT scan data of the skull. Holloway believes LB1 was probably not microcephalic, although the endocast has features that puzzle him. “This is extraordinarily dwarfed, with a brain size that some chimpanzees would snicker at, so I wouldn't call it normal.” The extremely thin protruding frontal lobes have led him to wonder if LB1 is an example of microgyria. In this condition, the cerebral cortex has only four layers instead of the usual six, but he notes this is not a hypothesis that can be tested easily. In lab animals, microgyria leads to brain reorganization and behavioural changes, and in humans it has been associated with epilepsy and dyslexia.
…the Hobbit story appears to have been designed for twenty‐first century media; when you look deeper at the story it becomes apparent that indeed it was
DNA studies, which could establish whether LB1 is H. sapiens or something completely different, are not likely to occur in the near future. A bone chip that was sent—accompanied by international outrage—from temporary residence in Jacob's laboratory to Svante Pääbo's laboratory at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, has as yet yielded no results, either positive or negative. Pääbo, one of the world's leading experts in the analysis of ancient DNA, does not give his studies a high chance of being successful, but added, “I would be delighted to work with the team excavating the site in order to explore this material further.” Alan Cooper from the University of Adelaide (SA, Australia), the discovery team's designated DNA expert, reports that he does not expect his search for DNA—which has so far been confined to sediments and plant material from the site—to hit its stride until 2006, with publication a long time after that. Conditions at the Liang Bua site are the worst possible for DNA preservation: hot and wet. But even if conditions were perfect, the peregrinations of the bones—to say nothing of the covert damage—have exposed them to considerable contamination from foreign genetic material, which is always a hurdle for studies of ancient DNA.
The reports of the discovery team on the 2004 digging season are expected soon. Team members say the new analysis backs up their contentions about a new Homo species, but with debate so polarized, it is doubtful that additional reports will persuade sceptics. The second mandible, despite being broken and inexpertly repaired, is said to be very similar to that of LB1. This is the strongest indication so far that, whatever the specimen is, she—or he—is not unique. However, according to John Hawks—a palaeoanthropologist at the University of Wisconsin‐Madison, USA—who has studied photographs taken in Jacob's lab, this similarity does not mean that nothing was amiss with these creatures. He says tooth and braincase oddities reported in the original paper, plus the projections in the front of the endocasts, suggest pathology, as do the postcranial bones. He notes that most of the other individuals are represented by a single bone or bone fragment. “There are mosaics of features across all the postcranial bones that suggest developmental abnormalities,” he said. “If the pictures that I have seen of the post‐crania had been included in the original Nature report, it would have never have made it past review.”
The truth, Hawks argues, would emerge with wider access to the bones. “Let's get a group of people in there who don't have a stake in one side being right, and let's open it up,” he said. “There's been a real lack of transparency that has led to the persistence of a legitimate scientific debate that could be settled fairly easily if there was more openness.”
The Hobbit story seems designed for twenty‐first century media because indeed it was. The US National Geographic Society has funded palaeontology research for many years, always promoting and portraying it as notably successful—sometimes even before journal publication. The Society has underwritten the Hobbit research, and its news on the Hobbit began appearing simultaneously with the Nature papers; television followed soon after. Nature accompanied the papers with its own press conferences, press kits, videos and news stories. The Hobbit tale is a natural draw, featured in print and broadcast media everywhere. Discovery team members have led journalists and TV crews to the dig site, taken part in teleconferences and appeared regularly in TV studios. Formerly inconspicuous palaeontologists, anthropologists and microcephaly experts are suddenly in demand. Broadcast networks, especially in Australia and the USA, launched TV specials. And there is no end in sight; Holloway and his cast of endocasts are scheduled to star in a BBC television special in the UK.
Hawks worries that the dispute has been bad for palaeoanthropology and good for creationism
The sponsors probably would have preferred that the Hobbit remained one of the Top Ten science stories of 2004. Instead, it has turned into a particularly rancorous scientific dispute, to say nothing of a territorial battle that has degenerated into name‐calling. Jacob has been quoted as saying the Australians on the discovery team lack expertise and has called them scientific terrorists. Morwood has countered that taking bone to Germany was unethical and illegal. Such comments have proven irresistible, even for some media that usually ignore science.
But, ultimately, the impact of the dispute on the science of human origins may be as small as the Hobbit itself. “It's extremely interesting and provocative, but it is not going to upset the apple cart on the whole picture of hominid evolution,” Holloway said. “It is clearly a localized phenomenon that took place on one small island in the Indonesian archipelago.”
Instead, Hawks worries that the dispute has been bad for palaeoanthropology and good for creationism. Searching the World Wide Web for information on the Hobbit, he pointed out, uncovers many creationist sites. “They're saying, ’Look! These people don't know what they're doing! They don't know what they're talking about! They're disagreeing about the most basic issues—about whether something is diseased or not!’”, Hawks commented. “It's wrong for them to do what they do, but we certainly make it easy for them when we have disagreements like this one. I think that a lot of what has been said is going to have to be retracted. Given the amount of media attention, it just makes the field look incompetent.” His conclusion: “Everybody wants a piece of this. Nobody is on the side of the angels now.”
- Copyright © 2005 European Molecular Biology Organization