Once upon a time, but not so long ago, in a tropical island midway between Asia and Australia, there lived a race of little people, whose adults stood just more than one metre tall. Despite their stature, they were mighty hunters. They made stone tools with which they speared giant rats, clubbed sleeping dragons and hunted the packs of pygmy elephants that roamed their lost world.
Strangest of all, this is no fable. Skeletons of these miniature people have been excavated from a limestone cave on Flores, an island 600 kilometres, or 370 miles, east of Bali, by a team of Australian and Indonesian archaeologists. Reporting their find in Wednesday's issue of Nature, they assign the people to a new human species, Homo floresiensis.
The little Floresians lived on the island until at least 13,000 years ago, and possibly to historic times. But they were not a pygmy form of modern humans. They were a downsized version of Homo erectus, the eastern cousin of the Neanderthals of Europe. Their discovery means that archaic humans, who left Africa a million years or so earlier than modern people, survived far longer into the modern period than was previously supposed.
The island of Flores is very isolated and, before modern times, was inhabited only by a select group of animals that managed to reach it. These then became subject to unusual evolutionary forces that propelled some toward giantism and downsized others. The carnivorous lizards that reached Flores, became giant sized and still survive, though now confined mostly to the nearby island of Komodo; they are called Komodo dragons. Elephants are excellent swimmers; those that reached Flores evolved to a dwarf form the size of an ox.
Previous excavations by Mike Morwood, a member of the team that found the little Floresians, showed that Homo erectus had arrived on Flores by 840,000 years ago, to judge from the evidence of crude stone tools. Presumably the descendants of these Homo erectus became subject to the same evolutionary forces that downsized the elephants.
In a written commentary accompanying the article, two anthropologists not connected with the find, Marta Mirazon Lahr and Robert Foley of the University of Cambridge, say it is "among the most outstanding discoveries in palaeoanthropology for half a century." The first little Floresian, an adult female, was found in September 2003, buried under about six metres, or 20 feet, of silt that coat of the floor of the Liang Bua cave in Flores. A team of paleoanthropologists headed by Peter Brown, of the University of New England in Armidale, Australia, identifies the skeleton, which is not fossilized, as a very small but otherwise individual, similar to Homo erectus. Because the downsizing is so extreme smaller than modern human pygmies they assign it to a new species.
In a companion report Morwood, an archaeologist who is also at the University of New England, estimates that the skeleton is 18,000 years old. He has since found the remains of six more individuals in the cave, with dates ranging from 95,000 to 13,000 years ago, he said in an interview.
Also buried in the cave are a number of objects that illustrate how the little Floresians lived. There are bones of Komodo dragons, beasts three metres in length, and of an even larger lizard. The dragons can eat animals the size of deer, but as cold-blooded animals they are sluggish at low temperatures and not so hard to kill. There are bones of the pygmy elephant, giant rat, fish and birds. There is evidence the Floresians knew the use of fire. And there is a suite of stone tools, considerably more sophisticated than any yet known to have been made by Homo erectus. The tools include small blades that might have been mounted on wooden shafts.
If the stone tools were made by the little Floresians, as Morwood believes, that is striking evidence of their cognitive abilities. Morwood says they must have hunted cooperatively to bring down the pygmy elephants. To conduct such hunts, and to fabricate such complex stone tools, they almost certainly had some form of language, he said.
This will be a surprising finding, if true, because the little people have brains slightly smaller than a chimpanzee and similar in size to Australopithecenes, the ape-like ancestors of the human line. Foley said he would not rule out Morwood's suggestion but noted that chimpanzees hunt cooperatively without using language. Modern humans are known to have reached Australia by at least 40,000 years ago and were probably in the general neighborhood of Flores at the same time, so it is plausible that they could have been the makers of the stone tools. "I think it's a big jump" to assume the Floresians had language, Foley said.
Morwood said he has found no sign of modern humans in Flores until 11,000 years ago so has no basis for associating them with the tools in the Liang Bua cave. G. Philip Rightmire, a paleoanthropologist at Binghamton University in New York, said he was persuaded that the tools were made by the little Floresians.
"It's a wonderful demonstration of apparently 'archaic' humans adapting to the special conditions on Flores," Rightmire said. "I wouldn't have supposed that such small-brained people descended directly from Homo erectus would be capable of producing these artifacts, but the evidence is pretty compelling." The new findings add to the rapidly emerging picture of Homo erectus, which has long been overshadowed by the better-known Neanderthals of Europe. Like the Neanderthals, Homo erectus generally disappears from the scene just before modern humans arrived in their territory. The little Floresians not only survived long into the modern period but unlike most of the other archaic human populations managed to coexist with them.
They also demonstrate the adaptability of the human form and how readily humans conformed to the same pressures for pygmification that affected other island species.
Most of the extraordinary finds in paleontology have been surprising because they were so old. "What's exciting about this one is that it's so late, telling us about the processes and patterns of evolution in a way that's deeply informative," Foley said.
http://www.rednova.com/news/display/?id=98395
Published: 2004/10/28 12:00:14 CDT
Copyright 2004 Rednova 2004
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