Homo floresiensis and Homo erectus may be close kin. The spread of the
3 foot men around Asia into the islands of Indonesia also brings to
mind other islands with "little" men in legend. The menhunes of
Hawaii, those elves in Iceland and other places, all the "myths" that
might hide big Sapiens cleaning out the little people.
How a hobbit is rewriting the history of the human race
The discovery of the bones of tiny primitive people on an Indonesian
island six years ago stunned scientists. Now, further research
suggests that the little apemen, not Homo erectus, were the first to
leave Africa and colonise other parts of the world, reports Robin
McKie
* Robin McKie
* The Observer, Sunday 21 February 2010
A painting of what researchers believe Homo floresiensis may have
looked like. Illustration: Peter Schouten
It remains one of the greatest human fossil discoveries of all time.
The bones of a race of tiny primitive people, who used stone tools to
hunt pony-sized elephants and battle huge Komodo dragons, were
discovered on the Indonesian island of Flores in 2004.
The team of Australian researchers had been working in a vast
limestone cavern, called Liang Bua, in one of the island's remotest
areas, when one scientist ran his trowel against a piece of bone.
Carefully the group began scraping away the brown clay in which pieces
of a tiny skull, and a little lower jaw, were embedded.
This was not any old skull, they quickly realised. Although small, it
had special characteristics. In particular, it had adult teeth. "This
was no child, but a tiny adult; in fact, one of the smallest adult
hominids ever found in the fossil record," says Mike Morwood, of
Australia's University of Wollongong and a leader of the original
Flores expedition team.
The pieces of bone were carefully wrapped in newspaper, packed in
cardboard boxes and then cradled on the laps of scientists on their
journey, by ferry and plane, back to Jakarta. Then the pieces of
skull, as well as bones from other skeletons found in Liang Bua, were
put together.
The end result caused consternation. These remains came from a species
that turned out to be only three feet tall and had the brain the size
of an orange. Yet it used quite sophisticated stone tools. And that
was a real puzzle. How on earth could such individuals have made
complex implements and survived for aeons on this remote part of the
Malay archipelago?
Some simply dismissed the bones as the remains of deformed modern
humans with diseases that had caused them to shrink: to them, they
were just pathological oddities, it was alleged. Most researchers
disagreed, however. The hobbits were the descendants of a race of far
larger, ancient humans who had thrived around a million years ago.
These people, known as Homo erectus, had become stranded on the island
and then had shrunk in an evolutionary response to the island's
limited resources.
That is odd enough. However, new evidence suggests the little folk of
Flores may be even stranger in origin. According to a growing number
of scientists, Homo floresiensis is probably a direct descendant of
some of the first apemen to evolve on the African savannah three
million years ago. These primitive hominids somehow travelled half a
world from their probable birthplace in the Rift Valley to make their
homes among the orangutans, giant turtles and rare birds of Indonesia
before eventually reaching Flores.
It sounds improbable but the basic physical similarity between the two
species is striking. Consider Lucy, the 3.2 million-year-old member of
Australopithecus afarensis. She had a very small brain, primitive
wrists, feet and teeth and was only one metre tall, but was still
declared "the grandmother of humanity" after her discovery in Ethiopia
in 1974. Crucially, analysis of Lucy's skeleton shows it has great
similarities with the bones of H. floresiensis, although her species
died out millions of years ago while the hobbits hung on in Flores
until about 17,000 years ago. This latter figure is staggeringly close
in terms of recent human evolution and indicates that long after the
Neanderthals, our closest evolutionary relatives, had disappeared from
the face of the Earth around 35,000 years ago, these tiny, distant
relatives of Homo sapiens were still living on remote Flores.
The crucial point about this interpretation is that it explains why
the Flores people had such minuscule proportions. They didn't shrink
but were small from the start – because they came from a very ancient
lineage of little apemen. They acquired no diseased deformities, nor
did they evolve a smaller stature over time. They were, in essence, an
anthropological relic and Flores was an evolutionary time capsule. In
research that provides further support for this idea, scientists have
recently dated some stone tools on Flores as being around 1.1 million
years old, far older than had been previously supposed.
The possibility that a very primitive member of the genus Homo left
Africa, roughly two million years ago, and that a descendant
population persisted until only several thousand years ago, is one of
the more provocative hypotheses to have emerged in anthropology during
the past few years," David Strait of the University of Albany told
Scientific American recently. This view is backed by Professor Chris
Stringer of the Natural History Museum, London. "We are still
grappling with what this discovery has done for our thinking and our
conventional scenarios."
In addition, Mike Morwood says he has now uncovered stone tools on
nearby Sulawesi. These could be almost two million years old, he
believes, which suggests the whole region was populated by very
ancient humans for a startlingly long part of human prehistory. "This
is going to put the cat among the pigeons," Morwood says.
However, it is the hobbits' similarity to ancient African apemen that
provides the most compelling evidence for their ancient origins. In
the Journal of Human Evolution, a team led by Debbie Argue of the
Australian National University, recently reported that analysis of H.
floresiensis shows they most closely resemble apelike human ancestors
that first appeared around 2.3 million years ago in Africa. In other
words, their stock may be not quite as old as Lucy's but probably
comes from a hominid, known as Homo habilis, that appeared on the
evolutionary scene not long after Lucy's species disappeared. Homo
habilis's features now seem to match, most closely, those of H.
floresiensis.
Consider those hobbit feet, for example. The skeleton unearthed on
Flores had a foot that was 20cm in length. This produces a ratio of 70
per cent when compared with the length of the hobbit's thigh bone. By
contrast, men and women today have foot-to-thigh bone ratios of 55 per
cent. The little folk of Flores had singularly short legs and long,
flapper feet, very similar to those of African apemen, even though
limbs like these would have made their long march from Africa to
Flores a painful business.
Similarly, the hands of H. floresiensis were more like apes than those
of evolved humans, their wrists possessing trapezoid bones that would
have made the delicate art of stone tool-making very difficult. Their
teeth show primitive traits while their brains were little bigger than
those of chimpanzees, though CT scans of skull interiors suggest they
may have had cognitive skills not possessed by apes.
Nevertheless, this little apeman, with poor physique, a chimp-sized
brain and only a limited ability to make tools, now appears to have
left Africa, travelled thousands of miles and somehow colonised part,
if not all, of south-east Asia two million years ago.
Scientists had previously assumed only a far more advanced human
ancestor, such as Homo erectus, was capable of undertaking that task
and only managed to do so about a million years ago when our
predecessors had evolved powerful physiques, a good gait and the
beginnings of intellect. Without these, we would have got nowhere, it
was implied.
Then along came little H. floresiensis which, quite simply, has "no
business being there," says Morwood. And you can see what he means.
Apart from the sheer improbability of a jumped-up ape travelling from
Africa to Indonesia, there is the particular puzzle of how it got to
Flores.
Primitive hominids were almost certainly incapable of sailing. So how
did it arrive on the island in the first place? It is a puzzle,
although Stringer believes the region's intense tectonic activity is
significant. "After the Indian Ocean tsunami in 2004, people were
found far out at sea clinging to rafts of vegetation. Things like that
could have happened regularly in the past and people could have been
swept out to sea and washed ashore on Flores. Alternatively, there
could have been short-lived connections between now separate islands."
Thus, ancient African apemen travelled half the world, made homes
across Indonesia and, in one case, were washed out to sea to end up
colonising a remote island that was already populated with pygmy
elephants, called stegadons, and giant Komodo dragons, which are still
found on the island. It is a truly fantastic tale, worthy of Rider
Haggard, and it has turned the study of human evolution on its head.
And then there is the report that dates the stone tools found on
Flores as being 1.1 million years old. "That is utterly remarkable on
its own," adds Morwood. "Until we found these dates, the longest
period of island isolation that we knew about occurred on Tasmania
where the aboriginal people were cut off from mainland Australia
11,000 years ago. We thought that was an amazing length of time. But
now we have found an island where early humans were cut off from the
rest of evolution for more than a million years." In addition, there
are those completed digs carried out by Morwood which suggest that
some type of human being was making stone implements up to two million
years ago.
A crucial aspect to this ...
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