Science Fair Project Encyclopedia
Homo floresiensis ("Man of Flores") is a species in the genus Homo, remarkable for its small body, small brain, and survival until relatively recent times. It is thought to have been contemporaneous with modern humans (Homo sapiens) on the remote Indonesian island of Flores. One sub-fossil skeleton, dated at 18,000 years old, is largely complete except for arm bones which may yet be found. It was discovered in deposits in Liang Bua Cave on Flores in 2003. Also here, parts of six other individuals, all diminutive, have been recovered as well as similarly small stone tools from horizons ranging from 94,000 to 13,000 years ago. The first of these fossils were unearthed in 2003; the publication date of the original description is October, 2004; and confirmation of species status will probably appear soon with publication of recent revelations (March, 2005) about the brain of Flores Man.
Flores has been described (in the journal Nature) as "a kind of Lost World", where archaic animals, elsewhere long extinct, had evolved into giant and dwarf forms through allopatric speciation. The island had dwarf elephants (a species of Stegodon, a prehistoric elephant) and giant monitor lizards akin to the Komodo dragon, as well as H. floresiensis, which can be considered a species of diminutive human. The discoverers have called members of the diminutive species "hobbits", after J.R.R. Tolkien's fictional race of roughly the same height. In the island's mythology there were common references to Ebu Gogo, a small furry man, even into the 19th century.
The first (and so far only) specimens were discovered by a joint Australian-Indonesian team of paleoanthropologists and archaeologists looking on Flores for evidence of the original human migration of H. sapiens from Asia into Australia. They were not expecting to find a new species, and were quite surprised at the recovery of the remains of at least seven individuals of non-H. sapiens, from 38,000 to 13,000 years old, from the Liang Bua limestone cave on Flores. An arm bone, provisionally assigned to H. floresiensis, is about 74,000 years old. Also widely present in this cave are sophisticated stone implements of a size considered appropriate to the 1 m tall human: these are at horizons from 95,000 to 13,000 years and are associated with juvenile Stegodon, presumably the prey of Flores Man.
The specimens are not fossilized, but were described in a Nature news article as having "the consistency of wet blotting paper". Researchers hope to find preserved mitochondrial DNA to compare with samples from similarly unfossilised specimens of Homo neanderthalensis and H. sapiens. The likelihood of there being preserved DNA is, however, low, as it degrades more rapidly in warm tropical environments; in such conditions it is known to degrade in as little as a few dozen years. Contamination from the surrounding environment seems highly possible given the moist environment in which the specimens were found.
Homo erectus, thought to be the immediate ancestor of H. floresiensis, was approximately the same size as another descendant species, modern humans. In the limited food environment on Flores, however, H. erectus is thought to have undergone strong island dwarfing, a form of speciation also seen on Flores in several species, including a dwarf Stegodon (a group of proboscideans that was widespread throughout Asia during the Quaternary), as well as being observed on other small islands.
Despite the size difference, the specimens seem otherwise to resemble in their features H. erectus, known to be living in Southeast Asia at times coinciding with earlier finds of H. floresiensis. These observed similarities form the basis for the establishment of the suggested phylogenetic relationship. Despite a controversial reported finding by the same team of alleged material evidence, stone tools, of a H. erectus occupation 840,000 years ago, actual remains of H. erectus itself have not been found on Flores, much less transitional forms.
The type specimen for the species is a fairly complete skeleton and near-complete skull of a 30-year-old female about 1 m (3 ft 3 in) in height. Not only is this a drastic reduction compared to H. erectus, it is even somewhat smaller than the three million years older ancestor Australopithecines, not previously thought to have expanded beyond Africa. This tends to qualify H. floresiensis as the most "extreme" member of the extended human family. They are certainly the shortest and smallest.
Homo floresiensis is also rather tiny compared to the modern human height and size of all peoples today. The estimated height of adult H. floresiensis is considerably shorter than the average adult height of even the physically smallest populations of modern humans, such as the African Pygmies (< 1.5 m, or 4 ft 11 in), Twa, Semang (1.37 m, or 4 ft 6 in for adult women), or Andamanese (1.37 m, or 4 ft 6 in for adult women). Mass is generally considered more biophysically significant than a one-dimensional measure of length, and by that measure, due to effects of scaling, differences are even greater. The type specimen of H. floresiensis has been estimated as perhaps about 25 kg (55 lb).
Inevitable comparisons with modern human achondroplasiacs (about 1.2 m, or 3 ft 11 in) or other dwarfs, are flawed, as these people are not generally proportionally smaller than other humans, only short-limbed.
In addition to a small body size, H. floresiensis had a remarkably small brain. The type specimen, at 380 cm³ (23 in³), is at the lower range of chimpanzees or the ancient Australopithecines. The brain is reduced considerably relative to this species' presumed immediate ancestor H. erectus, which at 980 cm³ (60 in³) had more than double the brain volume of its descendant species. Nonetheless, the brain to body mass ratio of H. floresiensis is comparable to that of Homo erectus, indicating the species was unlikely to differ in intelligence.
Indeed, the discoverers have associated H. floresiensis with advanced behaviors. There is evidence of the use of fire for cooking. The species has also been associated with stone tools of the sophisticated Upper Paleolithic tradition typically associated with modern humans, who at 1310–1475 cm³ (80–90 in³) nearly quadruple the brain volume of H. floresiensis (with body mass increased by a factor of 2.6). Some of these tools were apparently used in the necessarily cooperative hunting of local dwarf Stegodon by this small human species.
Flores remained isolated during the Wisconsin glaciation (the most recent ice age), despite the low sea levels that united much of the rest of Sundaland, because of a deep neighboring strait. This has led the discoverers of H. floresiensis to conclude that the species or its ancestors could only have reached the isolated island by water transport, perhaps arriving in bamboo rafts around 100,000 (?) (or if as H. erectus, then about 1 million) years ago. This perceived evidence of advanced technology and cooperation on a modern human level has prompted the discoverers to hypothesize that H. floresiensis almost certainly had language. These suggestions have proved the most controversial of the discoverers' findings, despite the probable high intelligence of H. floresiensis.
The other remarkable aspect of the find is that this species is thought to have survived on Flores until at least as recently as 12,000 years ago. This makes it the longest-lasting non-modern human, long outsurviving the Neanderthals (H. neanderthalensis) who went extinct about 30,000 years ago. Homo floresiensis certainly coexisted with modern humans, who arrived in the region 35,000–55,000 years ago, for a long time, but it is unknown how they may have interacted.
Local geology suggests that a volcanic eruption on Flores was responsible for the demise of H. floresiensis in the part of the island under study at approximately 12,000 years ago, along with other local fauna, including the dwarf elephant Stegodon.
The discoverers suspect, however, that this species may have survived longer in other parts of Flores to become the source of the Ebu Gogo stories told among the local people. The Ebu Gogo are said to have been small, hairy, language-poor cave-dwellers on the scale of H. floresiensis. Widely believed to be present at the time of the Dutch arrival during the 16th century, these strange creatures are said to have last been spotted as recently as the late 19th century.
Similarly, on the island of Sumatra, there are reports of a one metre tall humanoid, the Orang Pendek, which a number of professional scholars take seriously. Both foot prints and hairs have been recovered. Scholars working on the Flores man have noted that the Orang Pendek may also be surviving Flores men still living on Sumatra.
The discovery is widely considered the most important of its kind in recent history, and came as a surprise to the anthropological community. The new species challenges many of the ideas of the discipline.
Homo floresiensis is so different in form from other members of genus Homo that it forces the recognition of a new, undreamt-of variability in that group, and reaffirms an intellectual trend away from the idea of linear evolution.
No doubt this discovery provides more fuel for the fire of the perennial debate over the out-of-Africa or multiregional models of the speciation of modern humans, despite H. floresiensis not itself being an ancestor of modern humans. Already, voices have been heard arguing it further on either side.
The discoverers of H. floresiensis fully expect to find the remains of other, equally divergent Homo species on other isolated islands of Southeast Asia, and do not think it impossible, if not quite "likely", that some lost Homo species could be found still living in some unexplored corner of jungle.
Henry Gee , a senior editor of the journal Nature, has agreed, saying, "Of course it could explain all kinds of legends of the little people. They are almost certainly extinct, but it is possible that there are creatures like this around today. Large mammals are still being found. I don't think the likelihood of finding a new species of human alive is any less than finding a new species of antelope, and that has happened" .
Gee has also written that "The discovery that Homo floresiensis survived until so very recently, in geological terms, makes it more likely that stories of other mythical, human-like creatures such as Yetis are founded on grains of truth....Now, cryptozoology, the study of such fabulous creatures, can come in from the cold" .
Professor Teuku Jacob , chief paleontologist of the Indonesian Gadjah Mada University and other scientists reportedly disagree with the placement of the new finds into a new species of Homo, stating instead "It is a sub-species of Homo sapiens classified under the Austrolomelanesid race". He contends that the find is from a 25–30 year-old omnivorous subspecies of H. sapiens, and not a 30-year-old female of a new species. He is convinced that the small skull is that of a mentally defective modern human, probably a pygmy, suffering from the genetic disorder microcephaly or nanocephaly . Some scientists reportedly believe the skeleton found may be of a male and not a female. When interviewed on the Australian television program Lateline, Professor Roberts reportedly conceded that the skeleton may be that of a male rather than a female but he strenuously maintained the fossil is of a new species. A paper published in Science disputes the microcephaly theory.
In late November and early December 2004, in an apparent arrangement with discoverer Radien Soejono , Professor Jacob borrowed most of the remains from Soejono's institution, Jakarta's National Research Centre of Archaeology, for his own research (apparently without the permission of the Centre's directors , , , ). Some expressed fears that, like the Dead Sea Scrolls, important scientific evidence would be sequestered by a small group of scientists who neither allowed access by other scientists nor published their own research. However, Jacob returned the remains to the Centre, except for two leg bones, on 23 February, 2005 .
Homo floresiensis was first described in two papers which appeared in the journal Nature, a year after the discovery:
- Brown, P., et al. A new small-bodied hominin from the Late Pleistocene of Flores, Indonesia. Nature 431:1055-1061 (October 27 2004). 
- Morwood, M. J., et al. Archaeology and age of a new hominin from Flores in eastern Indonesia. Nature 431:1087-1091 (October 27 2004). 
- Kate Wong. The littlest human. 'Scientific American February 2005: 40-49 
- Press release from University of New England, Australia, where Profs. Morwood and Brown are Associate Professors.
- Journals and Science Revues
- Coverage in News @ Nature (does not include the scientific paper)
- Scientific American Interview with Professor Brown
- New Scientist article
- National Geographic: "Hobbit" Discovered: Tiny Human Ancestor Found in Asia
- National Geographic: "Hobbit" Brains Were Small but Smart, Study Says
- The Brain of LB1, Homo floresiensis (journal- Science)
- Critics silenced by scans of hobbit skull (Nature)
- News Sites
- Times story: Mystery hobbit man lived alongside humans
- Telegraph News article with information on the "Ebu Gogo" myths
- Washington Post
- The Guardian: Bones of Contention
- Video of the Lateline interview with Professor Richard Roberts (ABC News) Australia
- New find raises questions about earliest humans (CBC News) Canada
- Tiny Early 'Hobbit' Human Was Smart, Skull Shows (Reuters)
- 'Hobbit' dwarfs with smart brain, scans show (CBC News)
- BBC News
- Other Sites
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