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Here is an old BBC news article on this idea. The video mentioned in the article isn't the one I was thinking of but I'm going to watch it anyway.
Here is another article on it. I'm still looking for actual academic papers to post excerpts from.
I had the impression you were referring to Monte Vere in Chile. That is why the mention of human remains confused me. These articles are interesting. It would mean the first wave of migration from Asia to North America between 25,000 and 70,000 years ago was by people from southern Asia and the second wave, either shortly before 25,000 years ago or after 14,000 was from eastern and northern Asia.
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Originally Posted by Randicus Draco Albus
I had the impression you were referring to Monte Vere in Chile. That is why the mention of human remains confused me. These articles are interesting. It would mean the first wave of migration from Asia to North America between 25,000 and 70,000 years ago was by people from southern Asia and the second wave, either shortly before 25,000 years ago or after 14,000 was from eastern and northern Asia.
The article, and video, I remember was about Patagonia (Tiera Del Fuego) and hinted at the idea that the people that come to Australia over 50-60K years ago were part of a larger group. The inference was that some kept travelling the, what was then, mainland coastline and eventually ended up in the Americas moving as far as they could and only stopped when there was no where else to go.
The real problem with the theory, as with any theory, is the near complete lack of evidence. This is why they need to find usable DNA samples to go with the skeletal remains.
If there is a link between these two groups I would think there would be an occupation trail but with ocean levels having risen so far, anywhere between 150-200 metres, the ancient coastlines are well under water and the evidence of such a trail would be long disolved.
Considering the Polynesians did not settle in Hawai'i until about 1500 (1200? I forget.) years ago and moved south to New Zealand a thousand years ago, it is very unlikely they travelled en masse across the Pacific. According to the articles you linked, the researchers who believe their finds are people related to Australians have identified hundreds of individuals. That would represent a population of tens or even hundreds of thousands. That is why, if true, I think the most likely travel route would have been across Beringia and through the ice-free corridor between 70 and 25,000 years ago, with the second migration entering when the corridor re-appeared about 11,000 years later.
This article is interesting, moreso for the comments after it, but the actual article is another click away and is also an intersting read because of a few assumptions that may not even be true.
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Originally Posted by http://www.abc.net.au/news/2011-09-23/aboriginal-dna-dates-australian-arrival/2913010
"No-one else in the world can say 'I am descended from people who have been here 75,000 years'."
This simple sentence is a mistake at best or misleading at worst. Why? consider this sentence that from the same article.
Quote:
The genome, shown to have no genetic input from modern European Australians, reveals the ancestors of the Aboriginal man separated from the ancestors of other human populations 64,000 to 75,000 years ago.
This indicates they left the "other" group anywhere between 64-75K years ago, not that they have been in Australia for 75K years. It would have taken time from the time they left to the time they got here, possibly a few thousand years.
Quote:
Co-author Dr Joe Dortch, an archaeologist at the University of Western Australia, says the work is significant because it shows the timeline for people in Australia is more than 50,000 years.
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Originally Posted by Randicus Draco Albus
That is why, if true, I think the most likely travel route would have been across Beringia and through the ice-free corridor between 70 and 25,000 years ago, with the second migration entering when the corridor re-appeared about 11,000 years later.
I agree totally.
EDIT: I see where you may have thought I mean travel across the Pacific. When I said mainland coastline I meant the mainland of the Asian continent then onto the Americas. I can see no other way.
I cannot access the link, but I am assuming it is about the cave paintings that are too old for accelerated mass spectrometer dating to date, meaning the paintings are older than 50,000 years?
You see this is also part of the problem and doesn't help. "The basic fact of evolution may be incontrovertible" the thing is because of the gaps it isn't. I don't doubt evolution, I wouldn't have studied it and maintain an interest in it if I did, I just don't have that time and energy, but I do doubt the interpretation of it.
I think you could (perhaps) maintain evolution without the fossil record. The genetic similarities don't depend on it: if two entities both have four limbs, two eyes, etc they're going to have similar genes. The anatomical anomalies are difficult to explain without it. The nerve to the tongue goes straight there; the one to the larynx makes a detour down to the chest. In a giraffe, the larynx is inches from the brain, but the laryngeal nerve is a dozen feet long. Once you consider that the components in question may have evolved from something else, you're well on the way to an explanation. The old, pre-Darwinian taxonomies are mostly close to evolutionary clades because of we all carry so much evolutionary baggage.
I'd be curious being a lay person on what/how the switch was flipped in our brains that all of a sudden made us
tool makers and abstract thinkers. One century we are running as prey. The next we are tool makers and planners.
Like a flip of a switch in our heads. I know they blame meat and protein for that switch being flipped.
But dolphins, Chimpanzees, Baboons,Killer Whales,Squid, Octupus, all eat meat also. So I figure the explanation too simplistic.
I know/think I know, that human history, (as a lay person), shows that human ancestry spans many divergent human species through time.
From large humans to pigmy humans to Neanderthal, (Scary biker body build here). Some die out due to natural distaster, competition, or are assimilated. I know you guys know a lot more about the details than I do.
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Originally Posted by rokytnji
I'd be curious being a lay person on what/how the switch was flipped in our brains that all of a sudden made us
tool makers and abstract thinkers. One century we are running as prey. The next we are tool makers and planners.
Like a flip of a switch in our heads. I know they blame meat and protein for that switch being flipped.
But dolphins, Chimpanzees, Baboons,Killer Whales,Squid, Octupus, all eat meat also. So I figure the explanation too simplistic.
I know/think I know, that human history, (as a lay person), shows that human ancestry spans many divergent human species through time.
From large humans to pigmy humans to Neanderthal, (Scary biker body build here). Some die out due to natural distaster, competition, or are assimilated. I know you guys know a lot more about the details than I do.
I do not claim to know much in this regard but about 3MYA (Million Years Ago) the brain underwent a structural change and various things happened to allow that structural change to occur.
1. The cranial capacity become larger. (This is very well documented)
2. The Neocortex developed in mammals. The neocortex is the part of the brain that enable mammals to reason, develop ideas, develop language etc. (this is also very well documented)
3. There was a change in blood flow within the skull. (this is still, as far as I am aware, a theory that has many problems but it does explain changes of habit within (first) Australopiticines and (second) Homo. I can't easily find information on this but will keep looking.
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Originally Posted by Randicus Draco Albus
I cannot access the link, but I am assuming it is about the cave paintings that are too old for accelerated mass spectrometer dating to date, meaning the paintings are older than 50,000 years?
No there are other sites that are like that but this one deals with artefacts in a dig. Here is some of the text (most of it actually)
Quote:
Originally Posted by http://austhrutime.com/malakunanja.htm
Malakunanja II Arnhem land
This is a shallow rock shelter near Ngarradji Warde Djobkeng and Ja Ja Billabong, south of Malangangerr. It has faded paintings on its overhanging walls. The first excavation found charcoal dating to 18 000 years ago. Associated with the charcoal were a grinding hollow and 2 flattish mortars, one of which had clear traces of ochre.
Later excavations in the 1980s established Malakunanja as the oldest dated site in Australia. The first signs of Human occupation appear 2.6 m below the surface. The layers showing signs of human occupation were TL dated to between 61,000 and 52,000 years ago. Humans apparently appeared abruptly dated to 61,000 +9,000/-13,000. The sand below this layer was devoid of any signs of human activity. From a depth of 2.5-2.3 m there was dense occupation, from between 52,000 +7,000/-11,000 BP and 45,000 +6,000/-9,000 BP. More than 1500 artefacts were found in the lowest occupation layer.
Artefacts included those made from from silcrete, quartzite and white quartz, a grindstone, pieces of dolerite and ground haematite, chlorite and mica and red and yellow ochre. The researchers allowed for the earliest occupants to have trodden artefacts into the soft sand of the floor, putting the first occupation of the site at a conservative time of 52,000 years BP. Below the earliest occupation there was 2 m of sand that were deposited gradually over a period of 110,000 years.
I'd be curious being a lay person on what/how the switch was flipped in our brains that all of a sudden made us
tool makers and abstract thinkers.
Actually, we are not the only one to use and make tools. Chimpanzees have been observed making tools and putting them aside for future use. Such as stripping leaves off twigs and using them to pull ants out of anthills. But instead of making one tool to eat the meal, they will prepare several twigs, use one, and leave the rest beside the anthill for future use. They also have a rudimentary culture. Very simple by human standards, but exists nonetheless. The point being, there is no difference of kind between us and the other great apes, just a difference of degree.
As for sudden changes in brain structure, that is the wonder of genetic mutation. Over the course of time organisms experience random genetic mutations. Some are neutral, having no effect. Some are deleterious, decreasing an individual's chance to survive long enough to reproduce. Some provide evolutionary advantages that increase the chance of surviving long enough to reproduce. Obviously, more individuals with advantageous mutations will survive and pass their genes on to their offspring than those with disadvantages. The result is the portion of the population with the advantageous gene increasing and those with the deleterious gene decreasing, until the latter gene disappears from the genome. So applied to the theory of a change in blood flow (regardless if it true or not), if a few individuals have a mutation that creates increased blood flow in the brain, and the effect is to increase cognitive capacities, those individuals would have a big evolutionary advantage. More of them would survive to adulthood and make smart babies than their dumber kin surviving long enough to make less smart babies. Eventually, the less smart portion of the population will disappear.
Quote:
From large humans to pigmy humans to Neanderthal
There is only one human species. We have a little physical variation, but we are all the same species. That has not always been the case. Neanderthals were a different species of human. Between 100,000 and 35,000 years ago, there at least two different species of humans running around. How many were there? Good question.
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Originally Posted by DavidMcCann
I think you could (perhaps) maintain evolution without the fossil record. The genetic similarities don't depend on it: if two entities both have four limbs, two eyes, etc they're going to have similar genes. The anatomical anomalies are difficult to explain without it. The nerve to the tongue goes straight there; the one to the larynx makes a detour down to the chest. In a giraffe, the larynx is inches from the brain, but the laryngeal nerve is a dozen feet long. Once you consider that the components in question may have evolved from something else, you're well on the way to an explanation. The old, pre-Darwinian taxonomies are mostly close to evolutionary clades because of we all carry so much evolutionary baggage.
My thoughts with regards to this are difficult to explain so bare with me if it isn't clear. To me evolutionary theory indicates every living thing on this planet has a common ancestor. At different stages some things developed new features and these features kept developing within certain groups (this is the new branch on the tree so to speak). As some things kept evolving others things didn't evolve and remained for all intents and purposes close to identical as can be to the common ancestor. These things didn't die out they just didn't evolve.
Now if this is the case there should be potential, even if it has been dormant for billions of years, for the organisms that are the closest to the common ancestor to start evolving into what already exists. With the right conditions (environmental and other push-pull factors) I can't see why this cannot happen. This of course is purely conjecture but to me it is reasonable conjecture. Then again there would be competition over resources etc and that would probably cause the extremely quick demise of such things.
Now to your comment in a previous post about the remains of the "intermediate" stages being available to be found. To me, this is an opinion, there is as much chance of them being able to be found as there is the chance of the things we have found so far being found. In other words if they did exist it should be just as possible for them to be found as what has already been found. I hope that makes sense.
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Originally Posted by Randicus Draco Albus
Actually, we are not the only one to use and make tools.
Just to add to Randicus's post Dian Fossey's work is worth looking at. The things she observed made people rethink what they "knew" about other primates. These animals think, plan, and make and use tools.
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