Posted on 04/21/2006 11:14:50 AM PDT by blam
Java Man's First Tools
Richard Stone
INDO-PACIFIC PREHISTORY ASSOCIATION CONGRESS, 20-26 MARCH 2006, MANILA
About 1.7 million years ago, a leggy human ancestor, Homo erectus, began prowling the steamy swamps and uplands of Java. That much is known from the bones of more than 100 individuals dug up on the Indonesian island since 1891.
But the culture of early "Java Man" has been a mystery: No artifacts older than 1 million years had been found--until now. At the meeting, archaeologist Harry Widianto of the National Research Centre of Archaeology in Yogyakarta, Indonesia, wowed colleagues with slides showing stone tools found in sediments that he says were laid down 1.2 million years ago and could be as old as 1.6 million years.
The find, at a famous hominid site called Sangiran in the Solo Basin of Central Java, "opens up a whole new window into the lifeways of Java Man," says paleoanthropologist Russell L. Ciochon of the University of Iowa in Iowa City.
Although hominids apparently evolved in Africa, Indonesia is a Garden of Eden in its own right, with a wealth of H. erectus fossils.
The startling discovery 2 years ago of "hobbits"--the diminutive H. floresiensis of Flores Island--added a controversial new hominid to the Indonesian menagerie.
In 1998, Widianto found stone flakes in the 800,000-year-old Grenzbank layer at Sangiran, whose well-plumbed sediments reach back 2 million years.
Then in September 2004, his team struck gold in a layer dated by extrapolation from the rocks around it to 1.2 million years ago.
Over 2 months, they unearthed 220 flakes--several centimeters long, primarily made of chalcedony, and ranging in color from beige to blood red--in a 3-by-3-meter section of sand deposited by an ancient river.
The find, not yet published, could be even more spectacular than Widianto realizes, says Ciochon.
His team, which also works at Sangiran, has used ultraprecise argon-argon radiometric methods to date the volcanic strata overlying the levels excavated by Widianto to 1.58 million to 1.51 million years ago--making the flakes at least 1.6 million years old.
If the flakes were undisturbed, Ciochon says, they would represent "some of the earliest evidence of the human manufacture of stone artifacts outside of Africa." Their antiquity would match that of the oldest flakes found in China, at Majuangou, dated to 1.66 million years ago and also made of chert.
Indonesian tool kit. Homo erectus used small, finely worked tools on Java. CREDIT: RETNO HANDINI
But not everyone is convinced. Although the chert flakes are abraded, possibly by water, a few limestone flakes are remarkably sharp.
"The difference in preservation condition could indicate that we are dealing with secondary deposition," or flakes of different ages mixed together, cautions archaeologist Susan Keates of Oxford University in the U.K., who was at the talk. Others disagree.
"I feel their excavation is reliable, because the deposits are thick and undisturbed," says Hisao Baba, curator of anthropology at Japan's National Science Museum and the University of Tokyo, whose team has also uncovered H. erectus fossils and flakes on Java.
The Sangiran flakes "are fundamentally different"--smaller--than the stone choppers made by H. erectus in Africa, says Ciochon.
The evidence, he argues, suggests that Java Man had to range far for small deposits of good flint or chert and so created small, finely worked tools in contrast to the larger tools found in Africa.
Considering the scarcity of raw materials on Java, Ciochon says, it's "a remarkably fine technology."
Widianto will resume excavations in June. "I will be going deeper and deeper, older and older," he promises.
Really?
Really?
Really?
Yeah. All this time and some peoples have just *blazed* forward.
More meat in the diet?
There was some earlier debate in the paleoanthropological community as to the number of early human species in southern Africa between 3 and 1 million years ago. Conventional wisdom had it that two species existed, Australopithecus africanus and Paranthropus robustus. In contradiction to this view, Milford Wolpoff, of the University of Michigan, advocated the"single species hypothesis". It claimed that the differences between the southern forms were caused by age differences and sexual dimorphism of the specimens. Many researchers had problems with this hypothesis. For example, why in southern Africa were the supposed males dying at a different place than the supposed females? And why were they dated to almost a half a million years later? It was clear that a larger fossil record would be needed to prove or disprove this hypothesis.
Interestingly, the answer to the question of the southern African early humans would come from hundreds of kilometers away in East Africa. The discovery of two fossils, KNM ER 406 and KNM ER 732, at Koobi Fora in eastern Africa would provide the necessary expansion of the record needed to disprove the "single species hypothesis". Upon discovery its in 1969, ER 406 showed enough similar morphology to be assigned to the same species as OH 5; with the addition of ER 732, comparisons could be drawn between the two that could shed light on the nature of dimorphism in early humans. As these two specimens were examined, researchers found that the early humans of this period followed what is called the great ape model of sexual dimorphism. Male crania were larger than females, and more heavily constructed. While differences existed between the two skulls, these differences were exactly what would be expected between the sexes in other great apes.
The two southern African forms, however, did not fit this model of the distinction between the sexes. The differences were too great to be the result of sexual dimorphism. This observation favored the idea of two distinct species in southern Africa.
The final blow to the "single species hypothesis" was the 1975 discovery of the cranium KNM ER 3733, assigned now to Homo ergaster, in the same layer as ER 406, the "robust" form Paranthropus boisei. Scientists finally knew for sure that more than one species of early human coexisted in the same geographical area. The old single line of progressive evolution was, once and for all, split into branches. And the human family tree has never looked the same since.
The "Peninj mandible" is a nearly complete mandible of Paranthropus boisei. It provided researchers with their first understanding of the complete adult dentition and the structure of the lower jaw of this species.
http://www.mnh.si.edu/anthro/humanorigins/ha/bos.html
I find it difficult to believe a separate species can be assigned because of a different structure of a jaw. I think humans are/were humans.
All tools develop according to need; the more hostile the environment, the greater the need for tools.
Now we're in the age of toys.
Obviously a different species than the rest of us!
I disagree. Tools don't drop down out of the sky, somebody needs to invent them. A lot of this depends on pure, dumb luck.
Now we're in the age of toys.
You're saying I don't need my Blackberry? :-)
I can live with that, if they pick up all of them... :-)
> Obviously a different species than the rest of us!
That is how slavery is justified.
I never heard that before. So I guess humans have considered other humans as different species when it fit their purpose. I thought if they could reproduce, they were the same species. Didn't Thomas Jefferson prove we are all one species?
I think his name was something like...Howard Schultz.
They will make your yard a historic battleground and you will have to move.
Well, there are Jawas on Tatooine. Evolutionary offshoot? And yes, one would think we'd be starting the whole colonization thing by now. Lace Mars with bacteria that feed on hematite to get some greenhouse gasses going and drop some algae in whatever liquid water there is. Or let Howard Dean loose.
> I never heard that before.
Quite common. The Nazis thought of Jews, slavs, blacks, etc as "sub-human;" during the American slavery period there were many who thought of the blacks as not fully human; today there are some whackadoodles who read the Bible and somehow extract from it that blacks are "mud people" or some such nonsense; Islamic whackos see Jews as "apes."
Note: all of these groups rejected evolution.
It's far easier to enslave your fellow man when you decide he's not actually your fellow man.
> Didn't Thomas Jefferson prove we are all one species?
There's proof, and then there's whack-jobs.
> I thought if they could reproduce, they were the same species.
Slightly more complex than that. Witness ligers and tions.
> What is more amazing is the fact that most technological advances have taken place in the last 80 years.
The triumphs of the scientific method, good data retention/recovery systems and consumerism/capitalism are fully manifest. Reject any one of those, and progress will grind to a halt.
Written records can only be reliably dated to ~5,000 BCE. Once you get past ~ 5,000 BCE, the reliability of dating becomes, well unreliable, and the imagination component increases exponentially.
All the talk about 'humans' existing 1 MYA is speculation built upon assumption built upon interpretation.
Interesting to watch how easily people swallow the initial assumption and then quickly buy into the entire 'if, then, therefore' theory.
Well, I'm not buying any of it! :)
There is no way I can believe humans have been around for a million or more years.
Regardless of the evidence?
Why are written records the only you accept? There are dozens of ways we can accurately date things. Seems more than a bit arbitrary.
All the talk about 'humans' existing 1 MYA is speculation built upon assumption built upon interpretation.
Correct. There were no AMH 1 mya; that's why this article concerns Homo erectus.
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