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DISCLAIMER: I am trying to start a science discussion of a topic in paleoanthropology. I am not planning to discuss evolution per se. I refuse to answer any posts by evolution deniers and I strongly suggest that nobody else answer any of them either. All such discussions should be taken over to Not Quite Science, which is the proper forum for them. Having said that: Pardon me if I get a bit long winded in the back ground of my post. I'm not sure just how much the regulars here at SAGG know about evolution and the spread of mankind. There is a report in Nature News about new tool findings from Dmanisi, Georgia (that's Eastern Europe just East of the Black Sea, not the USA). The findings seem to indicate that there were hominins living in that area around 1.85 million year ago (MYA). This is before the the time of the first Out-of-Africa (OoA) episode, as we understand it right now. It has long been believed that Homo Erectus was the first form of man to leave Africa for a bigger world. However, it has been believed that H. Erectus evolved in Africa between 1.78 and 1.65 MYA, so these findings apparently preclude any possibility of H. Erectus having been the tool maker at Dmanisi. The researchers suggest the possibility that H. Erectus did not evolve in Africa, but rather in the Dmanisi area, then spread from there to Asia, where the first H. Erectus fossils were found, and back to Africa. So that the first OoA spread would have been some predecessor of H. Erectus. Now to my not extremely well informed comments on the story. I recall that a year or 2 back there was a story on PBS about the hobbit, Homo floresiensis. In that story they visited Dmanisi and told about some hominin fossils found there that weren't H. Erectus, and suggested that there may have been earlier OoA movements by other, and more primitive, hominins. They suggested that the hobbit may have been a remainder from this earlier OoA movement. Wikipedia has an article about the hobbit. Any way I have other sources that suggest that H. Erectus may not have been an African development. Ian Tattersall in his 1995 book "The Fossil Trail" suggests that the African fossils attributed to H. Erectus were in fact not H. Erectus. He suggests that Asian H. Erectus evolved separately in Asia. So There might not be a good reason to suggest a back flow from Dmanisi to Africa. Any good science comments? Bill Gill
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would there be any photographs of the evidence?
human footprints have been found in the U.S. alongside
dinosaur footprints , the footprints ended where water erosion did not uncover the prints so they lifted up slabs of sediment to follow the footprints and underneath the slabs the footprints continued.
that's pretty good evidence I would think.
is there anything that can be viewed or should we just think of it as a hoax?
could the shards or flakes of rock have been a natural occurrence?
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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I have only losely following the DNA story from the human genome project. Not my area at all but was interesting so I throw up the link http://www.ornl.gov/sci/techresources/Human_Genome/elsi/humanmigration.shtmlThe DNA certainly shows that there were many version of species of our ancestors in those era's and infact that is one of the key findings. My view is the idea that we were the "perfect species" and there was only one ancestor is a human ego thing not a science fact. We seem to always want to set ourselves as special in the world of nature. So I have no problem with the finding but I know a few in the science community will because of human ego.
Last edited by Orac; 06/10/11 02:57 AM.
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
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You might try looking up the famous, 1977 Laetoli footprints... They are the 3,5 million year old footprints of three humans walking close together in the damp ash, by the side of a river bed. One larger (heavier) individual (a male?) a lighter female, and a child. All three were walking together seemingly in a hurry. (Their gait, stride, heel and toe prints left in the sandstone rock gave the Anthropologist months of interesting work at that time) The best complete set of photos, and write up are, in the Sept 1998 issue of Scientific America. You are still able to purchase a copy of this magazine from Scientific America. (I advise you to do that) It is the best and easiest source to read, about the Laetoli Footprints since many religious bigots, unbelievers including Creationists, and the 'Intelligent Design' followers, have deliberately hacked and damaged all of the interesting scientific comments made at that time (1977-1978) plus many other amateur photos taken by the many people that came to view the Laetoli site, before it was sealed and covered up for posterity protection. It was uncovered some years later to remove tree roots that had grown thru the Glass fibre coverings threatning to destroy the site. I beleve it was the American Paul Getty who put up a few million $'s to reopen and reclose the site, a dozen years after it was first covered? I cannot remember, or be sure of that, but I do remember that the Creationists or others tried to discredit the whole scene 20 years ago. So much so that it is impossible to find anything today about the Laetoli site. I just have this item in my files.....I did have much more, but as soon as I put them out on the NET 20 years ago, they were damaged and virused away...unfortunately not realising the anti scientific comments at that time, were for real....So I did not keep copies of the excellent close up photos and comments of the 3 hominids footsteps. http://www.pbs.org/wgbh/aso/tryit/evolution/footprints.html
.  . "You will never find a real Human being - Even in a mirror." ....Mike Kremer.
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would there be any photographs of the evidence?
Photos won't show it isn't a hoax. Anyone can make old-looking footprints or tools and take a photo of them. If you don't trust the authors you'd need to inspect the actual items and make measurements yourself.
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For a long time the accepted idea was that there was a straight line of descent from some ape-like ancestor. From the fossil record they assumed that the line led through Homo Habilis, to Homo Erectus, to Homo Neanderthalensis, and finally to Homo Sapiens. Most of those ideas have been shown to be wrong, with the DNA evidence strongly supporting a more diverse background. The story I referenced in my first post certainly seems to indicate that the line is much more like a bush than the straight line in the older idea. For one thing it seems that the Neanderthals have been moved out of the line of descent, although some people apparently are still trying to claim that the Neanderthals are just a sub-species of Homo Sapiens (Homo Sapiens Neanderthalensis). In my opinion that has been completely shot down.
A lot of what I think is based on the writings of Ian Tattersall, so it kind of follows his view point. But to me what he says really makes sense. A lot more than the idea of just one straight line kind of aimed at us. Since evolution is a random thing it make sense that a number of different trials would occur before finding the one that works good enough to last.
And for the link with the Neanderthals. I saw a report last year that somebody who has been studying the Neanderthal genes had found a small amount of their DNA in our DNA. But it was found only in non-African populations. It suggested that there may have been some cross-breeding around 100 KYA, probably in the Middle East, after the last OoA episode. Of course this is the same time frame when they have found modern fossils in Israel in fairly close proximity to Neanderthal fossils at around the same time. Maybe there was some cross-breeding between the neighbors. And of course I figure that there will be more about the DNA evidence as time goes by. I will keep looking.
Bill Gill
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I personaly have several items that are some type of metal embeded in rock. one looks like a piece of a fence or something. and one looks like a tooth !!! Im not saying that they are really old , its just that where I found the items was beside a cannal that was recently dug on a piece of land that had never been developed. they are each embeded in what looks like sediment. and the rock resembles the same type of rock that the popular hammer below was found in.  it was that the area has never been disturbed in the past that causes me to wonder how these metal items got there at a depth of 5 - 6 ft underground. the metal seems so old that even when you use a file to etch the metal it only shines for a few days then dulls again but never rust. this is why I asked if there were any photos. that would help the thread or at least the exact location where the stone chips were found. it may be simple glacier action that produced the chips or shards of stone.
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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I wish you still had the photos , 3.5 million year old footprints !!
and walking side by side !!
I believe this even upsets the sumerian 450 thousand year
old alien dna manipulation of hominids so that they would have a work force on earth to mine gold.
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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I wish you still had the photos , 3.5 million year old footprints !!
and walking side by side !!
I wonder if they were actually walking side by side. Apparently one was walking the footprints of another, so they could have been separated in time. Of course photos still exist. There's one on that website. I guess other copies in libraries. Unless it's all a hoax, then that would explain nobody else paying attention! I believe this even upsets the sumerian 450 thousand year
old alien dna manipulation of hominids so that they would have a work force on earth to mine gold.
Haha.
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First, don't pander to Creationist myths. For Creationist stuff go to my post in NQS. The Laetoli footprints are well documented. Wiki has an article on them, with photos. They were found by Mary Leakey in 1974 and have been studied by very credible scientists and documented in very credible journals. They demonstrate that there were bipedal hominins at around 3.5 MYA. The chances of the walkers being separated in time are rather poor. They were created because the creatures were walking in volcanic ash that had been recently wetted by rain fall. Then they were preserved because the volcano erupted again and covered them up. If there had been much time between the 3 walkers the ash would have been dry and the foot prints would not have been preserved. The fact that they were preserved in volcanic ash was also very valuable, because volcanic ash is very easily datable using atomic decay rates. However, the Laetoli walkers, presumably Pithecanthropus Africanus, were not the first bipedal animals. Aridpithecus Ramidus was developing bipedalism at 4.4 MYA. Aridpithecus Ramidus was a part time bipedal animal. He was bipedal on the ground and quadrupedal in trees. According to This article in Wiki Ardi was not ancestral to Homo. So there were apparently several species working on bipedalism at the time. Bill Gill
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First, don't pander to Creationist myths. For Creationist stuff go to my post in NQS.
Huh?
erupted again and covered them up. If there had been much time between the 3 walkers the ash would have been dry and the foot prints would not have been preserved. The fact
Maybe you have your creationist radar set too sensitively. I was wondering how they knew they were walking side by side. Even a few seconds time difference would mean they're not walking side by side. Maybe they were an hour apart and just following the trail left by the previous ones to get somewhere independently. The side-by-side was supposed to show some social behavior. But I don't see how it can. Surely many animals would take the easiest route (the one already made) or follow the trail of others - well OK that's social, but not as much as modern humans.
Last edited by kallog; 06/14/11 10:22 AM.
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The creationist remark wasn't so much about your post, just a general warning to watch what you are replying to. I definitely would like to keep this thread about science. So any replies that seem to be aimed at creationist myths should be take over to NQS.
As far as walking side by side. There have been some that speculated beyond the evidence of the tracks. Some have tried to claim that the 2 in the lead were showing affection for each other by walking close together. We don't really know that, there are probably all kinds of reasons why they might have been walking close together. What we can say is that they were probably a group. After all there was not a big crowd of them there. It wasn't like walking down the street in a city. They were probably living in relatively small groups. Assuming that they were searching for food, or traveling to a place where they could find food or a place to spend the night then the group as a whole would probably be somewhat spread out over the landscape. We do know that they were close in time to one another. They were walking in what amounted to thin mud, which would probably have dried fairly quickly.
Bill Gill
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the Laetoli walkers, presumably Pithecanthropus Africanus Now all you people will learn that I am not omniscient. I do occasionally make a mistake. Where I said "Pithecanthropus Africanus" I should have said "Pithecanthropus Afarensis". Sorry about that. Bill Gill
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........................> I definitely would like to keep this thread about science. So any replies that seem to be aimed at creationist myths should be take over to NQS.
As far as walking side by side. There have been some that speculated beyond the evidence of the tracks. Some have tried to claim that the 2 in the lead were showing affection for each other by walking close together. We don't really know that, there are probably all kinds of reasons why they might have been walking close together. What we can say is that they were probably a group. After all there was not a big crowd of them there. It wasn't like walking down the street in a city. They were probably living in relatively small groups. Assuming that they were searching for food, or traveling to a place where they could find food or a place to spend the night then the group as a whole would probably be somewhat spread out over the landscape. We do know that they were close in time to one another. They were walking in what amounted to thin mud, which would probably have dried fairly quickly.
Bill Gill
You make a lot of sense Bill Gill, especially in regard to the two walking close together 3.6 million years ago.
I have taken some items from the afore mentioned Scientific America article, which bears out what you said above.
>
Since Darwin's time it was thought that once upright posture and bipedalism had developed, the hands were then free to evolve manipulative skills. Stone toolmaking, it was supposed, was the critical factor in the emergence of early man. This view, however, was not universally accepted. Some believed that the brain, not erect posture, led the way. Although functional analysis of hominid bones from Africa pointed to early bipedalism, the fossils themselves could not provide the definitive answer.
The Laetoli trackway settled the issue. Excavated by Mary Leakey and her team in 1978 and 1979, the trackway consists of some 70 footprints in two parallel trails about 30 meters long, preserved in hardened volcanic ash. The best-preserved footprints are unmistakably human in appearance and yield evidence of soft tissue anatomy that fossil bones cannot provide. It is significant that the earliest stone tools known are about 2.6 million years old, made nearly a million years after the footprints at Laetoli. The Laetoli hominids were therefore fully bipedal well before the advent of toolmaking—an event considered to define the beginning of culture—and the traces they left behind provide evidence that the feet led the way in the evolution of the modern human brain.
The Laetoli footprints are the most ancient traces yet found of humanity's ancestors.
The prints were impressed in volcanic ash in that location 3.6 million years ago, in sight of the Sadiman volcano 20 kilometers away, whose subsequent ash falls buried them under 30 meters of deposit. Over the aeons the landscape eroded, until now, less than a few feet of soil protects the fragile surface.
While lifting the tracks is doubtless technically possible, it would be enormously costly, require much research, and risk damage or loss. For these reasons, the decision to rebury the site has been made, and if future conditions allow the site to be opened to visitors, it will have been saved.
Mary Leakey may have had the last word when she examined the tracks together with other Anthropologists. She said:-
"Here at this point, and you do not need to be an expert tracker to discern that the lighter hominid stops, pauses, and turns slightly to the left, as though briefly scanning the landscape and then both continue on to the north.
This motion, so intensely human, transcends time. Three million six hundred thousand years ago, a remote ancestor—just as you or I—experienced a moment of doubt." <
. . "You will never find a real Human being - Even in a mirror." ....Mike Kremer.
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The creationist remark wasn't so much about your post, just a general warning to watch what you are replying to.
Still confused. I was replying to Paul wishing somebody still had photos. I have no idea how these footprints have anything to do with creationism.
reasons why they might have been walking close together.
Still don't see how we know or even remotely suspect they were walking close together. If it took an hour for the mud to dry out, they could have been a mile apart. If there's no evidence they were walking next to each other then the "showing affection" you mentioned wasn't there. So it really would be just speculation.
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Still don't see how we know or even remotely suspect they were walking close together. The probability is that they were walking together. If they had passed that way at different times, even a few minutes apart, it is unlikely that their tracks would have stayed aligned. They would have wandered back and forth, even if just a short distance. When people, or animals, walk together the tracks tend to stay somewhat aligned. So they were probably together. Saying anything beyond that about them is getting to be pure speculation. I think the important thing about the tracks is that they show bipedalism at that early stage in our evolution. There is still some controversy as to whether they show full time bipedalism. Some think they do, some think they don't. The difference is whether A. Afarensis lived on the ground, or moved back and forth between the ground and trees. And of course if they switched between walking and climbing, how much of the time did they spend doing each one. My opinion is that they probably did both walking and climbing. However, a million and a half years later Homo Ergaster was definitely a dedicated walker. So sometime in between A. Afarensis and H. Ergaster there was a breakthrough in the evolution of modern H. Sapiens that led, after another million and a half years to us. Bill Gill
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stayed aligned. They would have wandered back and forth, even if just a short distance. When people, or animals,
Ah.
full time bipedalism. Some think they do, some think they don't. The difference is whether A. Afarensis lived on the ground, or moved back and forth between the ground and trees. And of course if they switched between walking and
I guess it depends how full time it has to be. Even modern humans can live in trees (sort of). Seems to me that the walking shaped foot they had might have been less flexible for use as a hand like monkeys do. Still, I never realized anything like humans was alive 3.6 million years ago! Seems like they spent a long time not evolving much, or maybe getting killed off and having to start again.
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Still, I never realized anything like humans was alive 3.6 million years ago! Seems like they spent a long time not evolving much, or maybe getting killed off and having to start again. Well, there is some question about how human they were. Notice that they were Australopithecus Afarensis, not Homo Afarensis. However they are definitely counted as our cousins at a large remove. They were definitely not apes. If I recall correctly Australopithecus means Southern Ape Man, kind of part way between apes and men. They had larger brains than apes, but not as big as Homo. The first of our ancestors that was actually considered Homo was Homo Habilis (handy man). H. Habilis fossils were the first to be found associated with stone tools, hence their name. The first tools are dated around 2.5 MYA, and H. Habilis fossils first appear some time after that. Since the earliest H. Afarensis fossils go back almost 4 MYA the line of descent of human ancestors goes back to around 4 MYA, depending on how you count it. Ardipithecus Ramidus dates from around 4.6 MYA, and was a part time biped. Bill Gill
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If I recall correctly Australopithecus means Southern Ape Man, kind of part way between apes and men.
We are apes, Bill, of the family Hominidae, i.e. great apes, together with chimps, gorillas and orangutans. But I expect you know that, and I've just misunderstood you.
"Time is what prevents everything from happening at once" - John Wheeler
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We are apes, Bill, of the family Hominidae, i.e. great apes, together with chimps, gorillas and orangutans Well, and your family pet is a wolf who is much more closely related to the wild wolves than we are to the apes. The dog evolved from a wild predator to a human companion around 15,000 years ago. The last common ancestor of man and the living apes was something like 5 to 7 MYA. I think most everybody understands what we mean when we talk about man and apes separately. Bill Gill
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C is the universal speed limit.
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