Hobbit-Like Human Ancestor Found in Asia

National Geographic / New York Times, Homo Floresiensis debate1 of 12

Hobbit-Like Human Ancestor Found in Asia

Hillary Mayell
for National Geographic News

October 27, 2004

Scientists have found skeletons of a hobbit-like species of human that grew no larger than a three-year-old modern child (See pictures). The tiny humans, who had skulls about the size of grapefruits, lived with pygmy elephants and Komodo dragons on a remote island in Indonesia 18,000 years ago.

Australian and Indonesian researchers discovered bones of the miniature humans in a cave on Flores, an island east of Bali and midway between Asia and Australia.

Scientists have determined that the first skeleton they found belongs to a species of human completely new to science. Named Homo floresiensis, after the island on which it was found, the tiny human has also been dubbed by dig workers as the "hobbit," after the tiny creatures from the Lord of the Rings books.

The original skeleton, a female, stood at just 1 meter (3.3 feet) tall, weighed about 25 kilograms (55 pounds), and was around 30 years old at the time of her death 18,000 years ago.

The skeleton was found in the same sediment deposits on Flores that have also been found to contain stone tools and the bones of dwarf elephants, giant rodents, and Komodo dragons, lizards that can grow to 10 feet (3 meters) and that still live today.

Homo floresienses has been described as one of the most spectacular discoveries in paleoanthropology in half a century—and the most extreme human ever discovered.

The species inhabited Flores as recently as 13,000 years ago, which means it would have lived at the same time as modern humans, scientists say.

"To find that as recently as perhaps 13,000 years ago, there was another upright, bipedal—although small-brained—creature walking the planet at the same time as modern humans is as exciting as it was unexpected," said Peter Brown, a paleoanthropologist at the University of New England in New South Wales, Australia.

Brown is a co-author of the study describing the findings, which appears in the October 28 issue of the science journal Nature. The National Geographic Society's Committee for Research and Exploration has sponsored research related to the discovery. The find will be covered in greater detail in a documentary airing early next year on the National Geographic Channel.

"It is totally unexpected," said Chris Stringer, director of the Human Origins program at the Natural History Museum in London. "To have early humans on the remote island of Flores is surprising enough. That some are only about a meter tall with a chimp-size brain is even more remarkable. That they were still there less than 20,000 years ago, and [that] modern humans must have met them, is astonishing."

The researchers estimate that the tiny people lived on Flores from about 95,000 years ago until at least 13,000 years ago. The scientists base their theory on charred bones and stone tools found on the island. The blades, perforators, points, and other cutting and chopping utensils were apparently used to hunt big game.

In an accompanying Nature commentary, Marta Mirazón Lahr and Robert Foley, both with the Leverhulme Centre for Human Evolutionary Studies at the University of Cambridge, England, describe Homo floresiensis as changing our understanding of late human evolutionary geography, biology, and culture.

The discovery shows that the genus Homo is more varied and more flexible in its ability to adapt than previously thought. (The genus Homo also includes modern humans, Homo erectus, Homo habilis, and Neandertals—all of which are marked by relatively large braincases, erect posture, opposable thumbs, and the ability to make tools.)

"Homo floresiensis is an addition to the short list of other human species that lived at the same time as modern humans. I think people will be surprised to learn that not so long ago, we were not alone," said Brown.

Lost World of Tiny People

Despite its smaller body size, smaller brain, and mixture of primitive and advanced anatomical features, the new species falls firmly within the genus Homo. The researchers speculate that the hobbit and her peers evolved from a normal-size, island-hopping Homo erectus population that reached Flores around 840,000 years ago.

"Physically, they were about the size of a three-year old Homo sapiens [modern human] child, but with a braincase only one-third as large," said Richard Roberts, a geochronologist at the University of Wollongong, Australia, and one on the co-authors of the research paper. "They had slightly longer arms than us. More conspicuously, they had hard, thicker eyebrow ridges than us, a sharply sloping forehead, and no chin."

"While they don't look like modern humans, some of their behaviors were surprisingly human," said Brown, the study co-author.

The Flores people used fire in hearths for cooking and hunted stegodon, a primitive dwarf elephant found on the island. Although small, the stegodon still weighed about 1,000 kilograms (2,200 pounds), and would pose a significant challenge to a hunter the size of a three-year-old modern human child. Hunting must have required joint communication and planning, the researchers say.

Almost all of the stegodon bones associated with the human artifacts are of juveniles, suggesting the tiny humans selectively hunted the smallest stegodons. The Flores humans' diets also included fish, frogs, snakes, tortoises, birds, and rodents.

"The hobbit was nobody's fool," Roberts said. "They survived alongside us [Homo sapiens] for at least 30,000 years, and we're not known for being very amiable eco-companions. And the hobbits were managing some extraordinary things—manufacturing sophisticated stone tools, hunting pygmy elephants, and crossing at least two water barriers to reach Flores from mainland Asia—with a brain only one-third the size of ours.

"Given that Homo floresiensis is the smallest human species ever discovered, they out-punch every known human intellectually, pound for pound."

Both the tiny humans and the dwarfed elephants appear to have become extinct at about the same time as the result of a major volcanic eruption.

Mingling of the Human Tribes

There is no evidence of modern humans reaching Flores before 11,000 years ago, so it is unknown whether the hobbit intermingled with modern humans. The researchers found hobbit and pygmy stegodon remains only below a 12,000-year-old volcanic ash layer. Modern human remains were found only above the layer.

Still, rumors, myths, and legends of tiny creatures have swirled around the isolated island for centuries. It's certainly possible that they interacted with modern humans, according to the researchers.

"Looked at from a regional perspective, we definitely have modern humans in Australia from at least 40,000 years ago, and in Borneo from at least 43,000 years ago," Roberts said. "So there was temporal overlap between the hobbits and ourselves from at least 40,000 years ago until at least 18,000 years ago—more than 20,000 years minimum. What was the nature of their interaction? We have absolutely no idea. We need more sites and more hard evidence, and that's the next phase of our investigation."

Island Dwarfing

Researchers are also anxious to investigate how and why the hobbits came to be so small. When scientists discovered the hobbit remains, they thought it was the skeleton of a child. There was no record of human adults that were that small. Modern pygmies are considerably taller at about 1.4 to 1.5 meters (4.6 to nearly 5 feet) tall.

"H. floresiensis presents an intriguing problem in evolutionary biology," Brown said.

The most likely explanation is that, over thousands of years, the species became smaller because environmental conditions favored smaller body size. Dwarfing of mammals on islands is a well-known process and seen worldwide. Islands frequently provide a limited food supply, few predators, and few species competing for the same environmental niche. Survival would depend on minimizing daily energy requirements.

But there is no absolute proof that this is what in fact happened with this small human.

"While there are stone tools dated as far back as 840,000 years ago, no fossils of large-bodied ancestors have ever been found" on Flores, Brown said. "There is some possibility [Homo floresiensis] arrived on the island small-bodied."

"I could not have predicted such a discovery in a million years," said Stringer, of London's Natural History Museum. "This find shows us how much we still have to learn about human evolution, particularly in Southeast Asia."

October 12, 2005

A Big Debate on Little People: Ancient Species or Modern Dwarfs?

By JOHN NOBLE WILFORD

New discoveries in a cave on the Indonesian island of Flores, notably another jawbone, appear to give additional support to the idea that a separate species of little people new to science and now extinct lived there as recently as 12,000 years ago.

But a vigorous minority of skeptical scientists were unmoved by the new findings. They contend that the skeletal remains are more likely to be deformed modern human beings, not a distinct species.

The group of Australian and Indonesian researchers who announced the first findings a year ago and proclaimed the new species Homo floresiensis describe the additional bones in a report to be published tomorrow in the journal Nature.

They said the bones were fragments of nine individuals of unusually small stature, little more than three feet tall, and, judging by one skull, with brains the size of a chimpanzee's. The newly discovered lower jaw was almost identical to one previously found, except that it appeared to be 3,000 years younger.

"We can now reconstruct the body proportions of H. floresiensis with some certainty," the scientists, led by Michael J. Morwood and Peter Brown, both of the University of New England in Australia, said in the report.

"The finds further demonstrate," they continued, that the original skull and partial skeleton was not from "an aberrant or pathological individual, but is representative of a long-term population" that was present during the period from 95,000 to 12,000 years ago.

The implication that made the original discovery a year ago such a sensation was that these "little people of Flores," as they are commonly called, represent a distinct species that shared the earth with modern humans far more recently than anyone had supposed.

In a commentary in the journal, Daniel E. Lieberman, a biological anthropologist at HarvardUniversity, said, "All in all, it seems reasonable for Morwood and colleagues to stick to their original hypothesis that H. floresiensis is a new species."

But Dr. Lieberman noted that the authors were less certain of the new species' lineage than they had been a year ago. Then the discovery team speculated that the little people had evolved from Homo erectus, the immediate predecessor of Homo sapiens. Now they suggest in the report that the species may descend more directly from earlier members of the human family, like the australopithecines, the group the famous 3.2-million-year-old Lucy belonged to.

In an exchange of e-mail messages from Australia, Dr. Brown said, "The limb proportions, stature, brain size and skeletal robusticity of H. floresiensis replicated those in Australopithecus afarensis, not in any member of our genus Homo."

Dr. Brown said he was preparing to publish results of research that could explain what, if any, connection the little people had to Lucy.

But some paleontologists and biologists express strong doubts that the little people represent a new species. Two separate groups, including Indonesians, Australians, Americans and Britons, said this week that they were about to submit reports to a journal that they say refute the new-species hypothesis.

"I don't think anything is changed with this paper," Robert D. Martin, a biological anthropologist and provost at the FieldMuseum in Chicago, said in a telephone interview, referring to the latest Nature report. "I feel very strongly that these people are glossing over the problems with this interpretation."

In Dr. Martin's view, in which he is joined by several prominent scientists, the more likely explanation for the small stature is, in part, a phenomenon known as island dwarfing. People and animals living in isolation for many generations tend to evolve smaller bodies, their growth constrained by limited resources.

Dr. Lieberman, who wrote the commentary in Nature, said the dwarfing issue could be resolved if fossils of much earlier specimens of the Flores people were discovered.

"If the island-dwarfing hypothesis is correct," he wrote, "then the island's earliest inhabitants should be larger than the Liang Bua fossils."

Liang Bua is the cave at a remote Flores village where archaeologists found the first bones of the little people two years ago. Besides the skull and jaw, the bones included limbs and other fragments in deposits dating from 18,000 years ago; they were accompanied by remarkably advanced stone tools. The latest finds were from trenches at various depths and thus ages, some as recent as 12,000 years ago, indicating that the cave was occupied for tens of thousands of years.

Another possibility raised by the skeptics is that the discoverers happened to come on a people suffering from microcephaly, a disorder that causes abnormally small brain growth and other deformities.

Recently, British researchers examined the skull of a microcephalic individual at the Royal College of Surgeons of England and found that its braincase appeared to match that of the Flores specimen.

Robert B. Eckhardt, a professor of developmental genetics at PennState, complained that the new report on the additional jaw failed to support the thesis that these people were a separate species.

"All the paper tells us is that they have identified an early population of small people," Dr. Eckhardt said. "What we are disputing is that people with the brain size of a chimp made these stone tools in the cave. The easiest explanation is that the specimen with the small brain has a small brain because it is abnormal, not a new species."

• Copyright 2005The New York Times Company

August 22, 2006

Report Reignites Feud Over ‘Little People of Flores’

By JOHN NOBLE WILFORD

After the 18,000-year-old bones of diminutive people were found on the Indonesian island of Flores, the discoverers announced two years ago that these were remains of a previously unknown species of the ancestral human family. They gave it the name Homo floresiensis.

Doubts were raised almost immediately. But only now have opposing scientists from Indonesia, Australia and the United States weighed in with a comprehensive analysis based on their own first-hand examination of the bones and a single mostly complete skull.

The evidence, they reported yesterday, strongly supports their doubts. The discoverers, however, hastened to defend their initial new-species interpretation.

The critics concluded in an article in the current issue of The Proceedings of the National Academy of Sciences that the “little people of Flores,” as they are often called, were not a newfound extinct species.

They were, instead, modern Homo sapiens who resemble pygmies now living in the region and, as suggested in particular by the skull, appear to have been afflicted with the developmental disorder microcephaly, which causes the head and brain to be much smaller than average.

The international team of paleontologists, anatomists and other researchers who conducted the study was headed by Teuku Jacob of GadjahMadaUniversity, who is one of Indonesia’s senior paleontologists.

In the report, Dr. Jacob and his colleagues cited 140 features of the skull that they said placed it “within modern human ranges of variation.” They also noted features of two jaws and some teeth that “either show no substantial deviation from modern Homo sapiens or share features (receding chins and rotated premolars) with Rampasasa pygmies now living near LiangBuaCave,” where the discovery was made.

“We have eliminated the idea of a new species,” Robert B. Eckhardt, a professor of developmental genetics at Penn State who was a team member, said in a telephone interview. “After a time, this will be admitted.”

That time has not yet come.

Peter Brown, a paleontologist at the University of New England in Armidale, Australia, who was a leader of the team that discovered the “little people” bones, took sharp issue with the new report.

In an e-mail message, Dr. Brown said, “The authors provide absolutely no evidence that the unique combination of features found in Homo floresiensis are found in any modern humans.”

The features he referred to include body size, body proportions, brain size, receding chin, shape of premolar teeth and their roots, and the shape and projection of the brow ridge. But the critics asserted that many of the features in the specimen with the cranium, said to be diagnostic of a new species, are present in the Rampasasa pygmies.