Why the hell does blogger do that space thing to my posts?
oh well, here the entire story:
Species of tiny ancient human discovered Guy Gugliotta, Washington Post October 28, 2004 SMALL1028 Scientists have discovered a species of tiny ancient human that lived 18,000 years ago on an isolated island east of the Java Sea — a prehistoric hunter in a “lost world” of giant lizards and miniature elephants.
These “little people” stood about 3 feet tall and had heads the size of grapefruit. They co-existed with modern humans for thousands of years yet appear to be more closely akin to a long-extinct human ancestor.
Researchers suspect the earlier ancestor may have migrated to the island and evolved into a smaller dwarf species as it adapted to the island’s limited resources.
This phenomenon, known as the “island rule,” is common in the animal world but had never been seen before in human evolution.
“Not even in primates,” said paleoanthropologist Peter Brown, of Australia’s University of New England, a member of the multinational team reporting on the find today in the journal Nature. “But even though we have evidence of intelligence [in the new species], they were clearly subject to isolation and dwarfing.”
Artist’s conceptionPeter SchoutenAssociated Press”This is a great fossil find that speaks mounds about evolutionary experiments and the variation they caused,” said paleoanthropologist Ken Mowbray, of the American Museum of Natural History. “We have to step back and reevaluate everything we have. It’s really cool.”
The research team discovered the new species in a limestone cave on Flores Island, in the Indonesian archipelago east of Java.
They described the remains — a fairly complete skull, the jawbone and much of the skeleton — as those of a 30-year-old woman. The team named her Homo floresiensis.
Besides the woman’s skeleton, the team also found a tooth and a few bones from two other skeletons, and Brown said subsequent excavations had brought the team the remains of between five and seven people in all. “They’re all tiny,” Brown said in a telephone interview from Australia. “No big people.”
The new find is certain to influence a flourishing debate over the human presence both in Indonesia and on Flores, which lies immediately east of the so-called “Wallace Line” dividing those islands that were once connected to Australia or Asia, and those, such as Flores, that have been surrounded by water for the past 2.6 million years.
Generally speaking, islands west of the Wallace line, such as Java, display a full range of mainland animals.
On the isolated, ecologically limited eastern islands, however, animals often evolved in conformity with the island rule: Animals smaller than rabbits get larger; animals larger than rabbits get smaller.
Flores, with a limited food supply and no predators, was a prime example of this mechanism. At the time when the Flores woman lived, the island hosted both Komodo dragon lizards 3 feet long and a dwarf variation of Stegodon, a prehistoric elephant.
Flores project leader Michael J. Morwood, a University of New England archaeologist, in 1998 reported discovering stone tools on Flores that were 840,000 years old, a controversial find that did not immediately win broad acceptance. That site had no human remains.
Even more controversial is a dispute over bones found in Java. Some scientists say they are 300,000 years old, but others date them as recently as 27,000 years ago.
The later date now “seems more plausible” in light of the new discovery, said Rick Potts, director of the Smithsonian Institution’s Human Origins program, because Flores’ little people may be an evolutionary offshoot of the earlier species.
These earlier human ancestors, known as Homo erectus, arose in Africa about 2 million years ago and spread throughout Eurasia, beginning a bit less than 1 million years ago.
Despite the disputed 27,000-year-old date of the Java find, the preponderance of evidence suggests that Homo erectus went extinct perhaps 200,000 years ago. Modern humans arose in Africa about 150,000 years ago, reaching Australia 60,000 years ago and Indonesia 40,000 years ago.
The Flores woman has virtually nothing in common with modern humans, and while some traits — such as her small stature — pointed toward other, extremely early species, Brown said she most closely resembles a reduced-size Homo erectus, 3 feet tall with a grapefruit-sized brain.
The most plausible explanation for the small size is that the Flores people, like the animals with whom they lived, succumbed to the island rule. “You had limited availability of food and no predators,” Brown said. Short people had a better chance to survive.
The small brain, however, “is a big surprise,” Potts said, a major departure from the general evolutionary trend that the human brain grew over time.
A full-sized Homo erectus had a brain volume between 54.9 and 73.2 cubic inches, while modern human brains can reach 85.4 cubic inches.
Still, the evidence shows that the Flores people were far from stupid. Morwood, in a second Nature article, said the team found stone flakes, points and barbs indicating that the cave’s inhabitants hunted young Stegodon.
These artifacts were found in levels of excavation extending as far back as 95,000 years ago.
“How did they do it? The answer is to not look at brain size,” Brown said. “We don’t have many more neurons than chimps do, but we use them differently. I think the crucial thing was probably the brain’s internal organization.”
But on the question of how the little people got to Flores island, the team had no answers.
“The Stegodon were good swimmers, but the humans couldn’t have swum,” Brown said. “The popular notion is that they or their ancestors either intentionally or accidentally rafted in.”
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Richard Nixon's Guide to the Multiverse:
"It's contrarian and anti-authoritarian while espousing traditional values, a masterpiece of philosophical tension"