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Homo floresiensis

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Template:StatusPrehistoric Template:Taxobox image Template:Taxobox begin placement Template:Taxobox regnum entry Template:Taxobox phylum entry Template:Taxobox subphylum entry Template:Taxobox classis entry Template:Taxobox ordo entry Template:Taxobox familia entry Template:Taxobox genus entry Template:Taxobox species entry Template:Taxobox end placement Template:Taxobox section binomial Template:Taxobox end Homo floresiensis ("Man of Flores") is a suspected species of the genus Homo, thought to have been contemporaneous with modern humans or Homo sapiens on the remote Indonesian island of Flores. Seven skeletons and associated stone tools were discovered on Flores in 2004.

Flores has been described (in Nature magazine) 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 variety of Stegodon) and giant lizards akin to Komodo dragons, as well as Homo floresiensis—a kind of dwarf human. The discoverers have informally referred to the diminutive species as a hobbit, after J.R.R. Tolkien's fictional race of roughly the same height.

Specimens

The type specimen for the species is a near-complete skeleton of an adult female measuring roughly 3 feet (1 metre). These ancient people are thought of as "the most extreme" member to be entered into the extended human family. They are certainly the shortest. Despite their unusual size, the specimens seem otherwise to closely resemble Homo erectus, a species usually of about the same size as moderns known to be living in Southeast Asia at times coinciding with earlier finds of H. floresiensis. It is the opinion of the discoverers that H. erectus is the direct ancestor to H. floresensis, having undergone strong selective pressure for island dwarfing. However, they have not found remains of any large-bodied ancestors of H. floresensis. Nor have any male specimens been found.

The other remarkable aspect of the find is that these creatures are thought to have survived until at least as recently as 12,000 years ago on the island of Flores. The collection of bones and other items found at the site account for at least seven of these primitive individuals. The ages of the specimens range from 95,000 to 12,000 years old. The discovery is considered to be the most important of its kind in recent memory, as it indicates that a previously unknown hominin co-existed and probably interacted with modern humans, who are known to have colonised Flores well before the extinction of H. floresiensis.

The specimens are not fossilized, but were described as being "the consistency of wet blotting paper" [1]. Researchers hope to find preserved mitochondrial DNA to compare with samples from similarly unfossilised specimens of H. 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.

Characteristics

Although a member of the Homo genus, H. floresiensis was fundamentally different from modern humans. Yet, almost unbelievably, they lived until the threshold of recorded human history, almost certainly crossing paths with the ancestors of today's islanders. The discoverers suspect this species may be the source of the Ebu Gogo legend amongst the locals. The Ebu Gogo were, according to folk tales, human-like creatures which were the same height as Homo floresiensis. Henry Gee, a senior editor of the journal Nature, has said, "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."

H. floresiensis's body size may not have been competitive with modern humans. Their height may have been approximately 1 metre. Additionally, their grapefruit-sized brain was roughly a quarter of the volume of that of Homo sapiens, at around 23 in³ (377 cm³) — about the size of that of a chimpanzee. Even Homo erectus, modern man's closest ancestor, had a brain volume of around 60 in³ (980 cm³). Modern humans have a brain volume of 80 in³ (1300 cm³). Transitional prehuman species originating in Africa have brains closer in size to that of H. floresiensis; however, they lived more than 3 million years ago. Despite their small brains, evidence found gives reason to believe that H. floresiensis made stone tools, lit fires, and organized group hunts for meat. The isolated position of Flores suggests that the ancestors of H. floresiensis may have reached the island by boat around 100,000 years ago, suggesting a hitherto unsuspected technological capability.

Geological evidence gives rise to a theory that a massive volcanic eruption was responsible for the demise of H. floresiensis in the part of the island under study approximately 12,000 years ago; the same catastrophe may have wiped out the dwarf elephants at the same time.

Comparison to small modern humans

H. floresiensis is tiny compared to modern humans. The estimated height for an adult H. floresiensis, at 1 m, is considerably shorter than the average adult height of the physically smallest populations of modern humans, such as the African Pygmies (< 1.5 m), Twa, Semang (1.37 m for adult women), or Andamanese (1.37 m for adult women). Mass is a more generally significant scientifically than a one-dimensional measure of length, and by that measure, due to effects of scaling, differences are even greater, with H. floresiensis mass only about two-thirds that of the smallest Homo Sapiens populations. However it is thought possible by some researchers that H. floresiensis could really be just an even more extreme example of pygmification of modern humans.

Inevitable comparisons with modern human Achondroplasiacs (about 1.2m) or other dwarfs, are flawed, as these people are not generally smaller, only short-limbed. Homo floresiensis was small but more or less 'normally proportioned', analogously to modern human midgets.

Scholarship

H. floresiensis was first described in two papers which appeared in the journal Nature, a year after the discovery:

  • Brown, et al., "A new small-bodied hominin from the Late Pleistocene of Flores, Indonesia." Nature 431, 1055–1061 (October 28, 2004)
  • Morwood, et al., "Archaeology and age of a new hominin from Flores in eastern Indonesia." Nature 431, 1087–1091 (October 28, 2004)

See also

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