Or not.
A repost
Much is made of the early use of stone tools by human ancestors. Darwin saw the freeing of the hands ad co-evolving with the use of the hands to make and use tools which co-evolved with the big brain. And that would make the initial appearance of stone tools in the archaeological record a great and momentous thing. However, things did not work out that way.
It turns out that up-rightedness (bipedalism), which would free the hands, evolved in our ancestors a very long time (millions of years) prior to our first record of stone tools. The earliest upright hominids that are definitely human ancestors probably emerged either close to five million years ago or close to seven million years ago, depending on which of the current evidence you like and how you interpret it. The earliest chipped stone tools are a little over 2.5 million years ago.
Furthermore, at that time there was not necessarily any real increase in brain size. Maybe a little in one or two hominid lineages, but it is not clear which hominid lineage(s) were making stone tools in relation to the brain size and the increase in size is unimpressive to the extent that it is probably safe to say that as more fossils are found and more data analyzed it could go away.
It is true that about the same time stone tools show up (give or take a couple/few hundred thousand years) there may have been an increase in species of hominds, and/or an increase in some of the features that they shared, such as whopping big teeth and the skeletal and muscular aparatus to use those teeth. But it is also true, as Alison Brooks and I have shown in various analyses, that it is just as likely if not more likely that the appearance of stone tools in the archaeological record at that point in time is a function of how the arcaheoligcal record is formed. We beleive that it is fairly likely that chipped stone tools were already in use and simply became visible to us at this point. Maybe.
Which brings us to some very serious speculation, but what the heck: I think that what it takes, mentally or neurologically, to make this early, relatively simple stone tool technology is well within the range of capacities I can imagine for a chimp-like hominid. True, modern chimps have a hard time making stone tools, but their "hands" are not "freed" like a more bipedal hominids' hands would be. The mental/neurological part is not so hard. In a series of experiments some years ago, started by Glynn Isaac, we had many dozen Harvard Undergraduates, who had no prior exposure to stone tool manufacture, bang rocks together (in isolation) for the sole purpose of making sharp edged pieces. All of them managed to replicate most of the products in a typical Oldowan industry in just several minutes. The collection of any dozen or so of these students' produce includes all of the Oldowan "tool" forms.
The Oldowan is the outcome of breaking rocks.
As to the impact that Oldowan style technology would have on the life of a chimp-like human ancestor? This would probably be as important as any other single aspect of foraging strategy. I imagine they were mainly making sharp edges in order to sharpen sticks, or to cut into things (or both), which would have increased the range of possibilities for accessible foods at the same level that, for instance, cooperative hunting that we see in the Tai chimps of West Africa. Important. Not necessarily overwhelmingly important.
Humanities & Social Science
Comments
You never heard of Olduwan Kenobi? He was an important tool in the fight against the empire....
Posted by: IanW | February 10, 2010 7:55 AM
I suspect that "many dozen Harvard Undergraduates" are representative of our species.
They should retry the experiment with many dozen sanitation workers or employees of the Registry of Motor Vehicles and see what develops.
PS: bribing with beer is not allowed.
Posted by: NewEnglandBob | February 10, 2010 8:23 AM
New Enlgand Bob: What are you saying, exactly?
Posted by: Baruk | February 10, 2010 9:29 AM
Modern humans have levels of manual dexterity that are many orders of magnitude greater than that of other primates. Acquisition of nut cracking skill by capuchin monkeys (Cebus apella) using stones as hammer and anvil takes about 2 years and requires considerable repetitive nonproductive effort while watching proficient individuals.
http://www.ncbi.nlm.nih.gov/pubmed/15719240?
How long would it take a human to learn to crack nuts? A few minutes?
You are making the mistake of projecting that it can't be that hard because it is easy for you. It is easy for you because you already have the manual dexterity that a couple million years of evolution have developed in humans.
Posted by: daedalus2u | February 10, 2010 9:31 AM
How long would it take a human to learn to crack nuts? A few minutes?
We actually know this. No, not a few minutes. To be as good as chimps, several hours practice over several days. But the best humans are way better than chimps, and that takes a much longer time (there are very few super-cracker experts, but they are the product of years of practice and can do any kind of nut with nearly zero splintering or mushing of nut).
Posted by: Greg Laden | February 10, 2010 9:41 AM
They should retry the experiment with many dozen sanitation workers or employees of the Registry of Motor Vehicles and see what develops.
I would think that people who do jobs that require a lot of manual work would be likely to learn it even faster than the college students.
Posted by: Paul S. | February 10, 2010 9:50 AM
I should clarify: I don't mean several hours of practice a day for several days. I mean a total of several hours but distributed over days (so the learning is better).
Posted by: Greg Laden | February 10, 2010 9:54 AM
It wouldn't surprise we if we eventually discover conclusive evidence that some australopithecines were making stone tools.
Posted by: Charles | February 10, 2010 1:32 PM
See how easily cutting and sharpening sticks just smuggled in there. No evidence of this in chimps in the wild, is there? Sure they can learn it in the lab, but it is a major and relatively unheralded achievement in hominin evolution.
Davidson, I., and W. C. McGrew. 2005. Stone tools and the uniqueness of human culture. Journal of the Royal Anthropological Institute 11:793-817.
Posted by: Iain | February 10, 2010 3:07 PM
Sharpening sticks to dig up roots, no doubt!
Posted by: Kaiser | February 10, 2010 7:31 PM
Perhaps not sharpening exactly, but making a termite foraging stick brushier at the tip would seem to relate Iain. At least on chimp managed this.
Posted by: DrugMonkey | February 10, 2010 8:00 PM
and dude, you should totally make a JoVE video of some people knapping flints. That would be awesome.
Posted by: DrugMonkey | February 10, 2010 8:02 PM
Ian, this is a problem, isn't it?
I don't quite see a chimp sharpening a stick with a flake. But there are those, as you know, who see wood working on the flakes. I'm not going to defend that position, but I'm not going to rule it out either.
So either we have more advanced hominids back a bit farther in time than the fossils suggest, allow for the fossils to suggest a more advanced hominid, have the flakes be used for very rudimentary purposes, reconceive australopiths, or find believable modification of tools by chimps.
As to the relative timing (Brooks and Laden) the same can be said of the fossils as the stone. (but in differnt ways)
Posted by: Greg Laden | February 10, 2010 8:08 PM
I am prepared to argue this till the cows come home. There are serious problems with a research strategy which explains away all differences between chimps and hominins. If we want to understand how the creatures that became us differentiated from those ancestors that became chimpanzees i believe we should start by forming hypotheses about the differences between humans and chimpanzees.
So, i think there is a conceptual (hence cognitive) difference between "cutting" and what chimps do. Modifying objects which remain the same object is not the same as stripping leaves off a grass stem. BUt neither is stripping leaves off a grass stem the same as cutting bits of wood off a stick to make a shape in the stick that was not there before. Cutting meat off a carcase is not the same as ripping a limb of a monkey. I'll start there.
Then, as our 2005 paper showed, the other feature that stone tools give you is the debris from knapping.
And finally, Greg, the Lokalalei cores are a long way from the classic conception of Oldowan (however much I like the characterisation of Oldowan that your experiments with Glyn depends on).
Posted by: Iain | February 10, 2010 8:15 PM
I agree completely. The problem is, I just don't know what an Australopith is. Also, I am not impressed at all with our ability to put terminal dates on the hominds. Also, I am not impressed (as are you not as well) with the pre- Bed I Oldowan = Oldowan equivalence, but flakes are flakes and if all we are talking is flakes, then things like raw material may be more important.
Posted by: Greg Laden | February 10, 2010 8:20 PM
The Australopithecus (or Paranthropus) hand is more human like than chimp like. Well, some of them are anyway.
Posted by: AnneT | February 10, 2010 8:22 PM
Agreed. In the end I run away from the skeletal classifications. I know it is a cop out, but I think there is too much that depends on the methods. As I result I am not sure you can do much if you start from the classifications of the fossils.
I should also note that there is a really serious crisis in classification caused by the controversy over H. floresiensis (or whatever you might want to call it). Here is a creature that seems to have been around since earlier than the move on (most) modern humans out of Africa/SWAsia, that has been classified as closest to Australopiths (which are otherwise unknown outside Africa), H. erectus, Homo sapiens but sick, Homo sapiens but small. If Physical anthropology cannot agree on the position in the whole scale of hominins of a creature which is known from an almost complete skeleton, then there is something seriously problematic about the methods of classification. I am not taking sides for this argument, though I have a view. The objective statement of the methodological problem is uncontestable (except by someone who is absolutely committed to one of the classifications). But the methodological problem carries through to all classifications of hominin skeletal remains, most of which is actually less complete than LB1.
As it happens, Mark Moore's analysis of the stone tools is probably one of the best of many good analyses from Liang Bua--but I would say that about my student's work, wouldn't I.
Posted by: Iain | February 10, 2010 8:29 PM
It seems to me that if you have enough chimps, and enough sticks, and enough rocks ... and maybe some M&Ms;
Posted by: Paul | February 10, 2010 8:32 PM
That experiment has been done (without the m&ms;) and it produced chimps. NO cutting--even when the chimps miss nuts on stone anvils and make flakes.
Of course Kanzi and Panbanisha responded extremely well to the m&m; scenario (with onions and potatoes in my experience) and make good stone flakes. But like some people other than archaeologists intent on stone tool classification, the flakes were what they wanted cos they were sharp enough to cut the string to open the box.
Posted by: Iain | February 10, 2010 8:41 PM
Iain: I agree that the taxonomy is not as helpful as one would like. Sts 5 is now a classic object lesson in transgender and transmorphological hominids.
I like to think of there being a regular and robust (toothwise) model head and a chimpy and a homo-y model body, which might or might not come in all possible (four) combinations with sufficient geographic coverage that maybe there are two or more geographic "species" per morphological species, for the period of time from 3-point-something to whenever they end (two or one point something).
I like to think of the robust form (or robust end of the spectrum) as the same as the regular model but with more of whatever it is that is making the teeth big, etc.
And, of course, I like to think of what is making the teeth big, etc. the eating of USOs. Of that I'm more sure now than ever.
The thing is, related to your earlier comment about chimp-human differences being the key framework (and I agree with that), these "classic" australopiths are different from chimps in ways that are not like Homo (as you know, as we all know) thus complicating the matter.
Oh, and let's throw this in for fun: Our work lately has been with root eating adaptations in rodents. So, one of the other major root eating lifestyle to emerge in the savannas and semi arid regions of Africa is, of course, a eusocial creature. Just sayin'
Posted by: Greg Laden | February 10, 2010 8:42 PM
It's not necessary that early hominids broke rocks to obtain sharp edges. They would only have had to bend over and pick them up. Natural fires simultaneously heat treat and flake exposed flint to produce very sharp flakes. I have seen this. The deliberate flaking may have come later.
BS
Posted by: Blind Squirrel | February 10, 2010 8:51 PM
Blind: The quality, consistency, and availability of sharp edges from fire cracked rock vs. flaked stone are quite different. For the most part the kind of rock that is likely to crack from fire is actually different from the kind of rock one wants to flake, and the angles obtained and percentage of sharp edge surface you get from flaking are very different.
However, yes, sharp rocks do exist in nature, and one might well expect their use by a chimp-like (or chimp-minded?) hominid as preceding and/or being different from flaked stone.
Posted by: Greg Laden | February 10, 2010 8:54 PM
Be aware that I specified flint. What I meant to make clear is that developing the idea of using sharp pieces of flint as edges was no more difficult than picking them up off the ground. I was not implying that the sole source of the flints was natural fire cracked rocks. Deliberate flaking would have come later. For one thing, heat treating is not all that ancient.
I am aware of the difference in angles, efficiency etc, Having taught flint knapping for the last 15 years.
BS
Posted by: Blind Squirrel | February 10, 2010 9:13 PM
Ah, sorry, I missed that.
So, what is the context in which you teach flint knapping? Do I know you? (Well, there are a lot of flint knappers out there, I suppose...)
Posted by: Greg Laden | February 10, 2010 9:24 PM
North House Folk School. There are quite a few knappers (but relative to what?), but not all that many teachers. Most teaching is done informally at knapp-ins. John Whittaker sometimes shows up at them.
BS
Posted by: Blind Squirrel | February 10, 2010 9:36 PM
I am way out of my depth on the classification stuff you write of, Greg, but growing a bit of sympathy for USOs. ON classification, my bias would be to be a lumper because I think that is the best way of getting at variation on which selection might have operated. I always remember Peter Brown saying that there were, indeed, two populations of people in the Australian skeletal record, rather as Thorne and Wolpoff claimed, but they were called Males and Females!
I am perfectly happy that there might have been sharp stones to use in the environment (and of course there were the moment after the first knapping event was abandoned). But flint? Am I wrong about there being relatively little flint in Africa?
But then the next question is: can we get any evidence to evaluate the hypothesis that naturally sharp stones might have been used? I would guess that we could sample them and do use-wear or residue analysis on them, but because of the lack of patterning implied by the hyothesis there may be too many to sample meaningfully.
Posted by: Iain | February 10, 2010 9:48 PM
BS
Posted by: Blind Squirrel | February 10, 2010 9:55 PM
Am I wrong about there being relatively little flint in Africa?
Aha, an interesting question. There is approximately zero flint in Africa. I know of none offhand, but it's a big place, so maybe.
A huge region of Africa (well, five or so regions) are cratonic heavily eroded hilly plains with really nothing but quartz and duracrust, and duracrust sucks. Well, so does quartz.
There is chert, here and there.
There is obsidian in a number of places.
There are chert-like metamorphics that are somewhat more common, e.g. jasperite in large areas of South africa (my survey area's main stone of choice).
Basalt and various basalt-like or rhyolite-like (flow volcanics) rocks probably make up the bulk off Acheulean material for no other reason than the 12 or so sites in South Africa and a few in East Africa that make up something like 80 percent of the known lithic record by bulk they are so freakin' big. (And I exaggerate by less than one order of magnitude).
As you know, many people have written off raw material as a factor in technology. I have seen with my own eyes perfectly good "levelois" cores made of quartz and of jasperite (which is physically impossible to knap for a modern human, IMHO, without a geology hammer) so that may be true. But the range of these materials and overall crappiness of much of it and what looks to me like a vague correspondence between lithic "traditions" (or cultures or whatever you want to call them) and some of these raw material provinces makes me wonder.
Posted by: Greg Laden | February 10, 2010 9:59 PM
I have no hope for testing the idea that naturally sharp stones from any distant past were used.
Posted by: Greg Laden | February 10, 2010 10:01 PM
Blind Squirrel, did you see the Walker material?
Posted by: Greg Laden | February 10, 2010 10:03 PM
BS
Posted by: Blind Squirrel | February 10, 2010 10:06 PM
Ok, it has been fun, but I guess that leaves us at a dead end, doesn't it? An untestable hypotheses for which the most plausible conditions do not exist in the place they would need to. I am not one to criticise hypotheses for which there can be no evidence (having been accused of that--wrongly of course) but ... :-)
Posted by: Iain | February 10, 2010 10:06 PM
Indirect percussion could work. But, there are no antlers in Africa, a major factor in the history of later periods of flintnapping. No copper in the region or time period either.
I would assume some kind of special kickass hammerstone one of which I have never found, or mondo strength.
I'm not an expert flintknapper, but I can make a flake come off a rock. But not with this jasperite. Yet, it was done.
Posted by: Greg Laden | February 10, 2010 10:08 PM
BS
Posted by: Blind Squirrel | February 10, 2010 10:09 PM
BS
Posted by: Blind Squirrel | February 10, 2010 10:15 PM
Semantics! Flint and chert are distinctly different in Old World terminology: Flint comes as nodules in limestone deposits. Chert is everything else (that is flint/chert).
In the new world the terms are either used interchangeably or in some cases people have local preferences. In NY it is all chert. In other areas some things are called flint. In some places, if it is shinier it is flint. These are all superficial meaningless differences.
SO, although my initial traiing was NW, I've been mainly OW since 1985, thus I classify the African material (chert) as selected cherts from duracrusts.
Oh, there is flint/chert in some of the South African limestones, I think, but it is not used. I think it comes in tiny pieces. My memory on that is a bit vague.
I have not seen the Northern Minnesota (Walker) material myself. I have no opinion on its age. Everyone I know involved or who has seen is is a respected expert and they seem to differ in their opinions. If anything is going on there this year I'd love to have a look.
Posted by: Greg Laden | February 10, 2010 10:18 PM
BC, do you know what Tiger's Eye is?
The Tiger's Eye is the yellowish, slightly glassier and sightly (very very slightly) harder layers of this jasperite. If I had some chunks I'd give it to you but alas, I don't. But if you ever go to South Africa I can fix you up with my knapper friends there, and they can bring you to the Asbestos Hills to give it a try.
I'd love to know about these pictures of natives using horn.
Posted by: Greg Laden | February 10, 2010 10:21 PM
Oh, the Walker material is from Norther MN. Hehehe. One of my knapping buddies is tight with a couple of the state archeologists. They claim that the only people who are enthusiastic about that material are the people on the dig. It's all unifacial, indistinguishable from high velocity water cracked rocks. Also curiously indifferent to the type of rock used. I don't have the picture of the horn indirect, sorry.
BS
Posted by: Blind Squirrel | February 10, 2010 10:34 PM
Iain, sorry your comment was moderated for a moment there. You said the magic word, I guess.
Which is hopeless, the random sharp edge hypothesis, or the idea of flakes being used for making sharp sticks hypothesis?
I don't think hypotheses that specific are likely to be tested, either way.
Posted by: Greg Laden | February 10, 2010 10:38 PM
The tiger's eye from Mexico is considered unknappable. It lacks any semblance of a concoidal fracture.
Did you really mean to distinguish flint as occurring in limestone? The reason I ask is because the arbitrary definition I am most familiar with has flint occurring in chalk and the limestone product called chert.
BS
Posted by: Blind Squirrel | February 10, 2010 10:44 PM
Yes indeed, chalk is what I mean to say. I was eve thinking chalk as I typed limestone, apparently.
Posted by: Greg Laden | February 11, 2010 12:14 AM
OK you got me back. I was a little worried about the appearance of moderation (should never be in excess, hey). I am pretty sure the most untestable bit is the use of sharp rocks from the environment, my point being that it sounds as if that would be more implausible in an environment where there was little fine-grained siliceous rock such as flint.
The other hypothesis has probably been tested and supported. When I was taken with meat-eating as the big difference, I, like so many others, looked at the Keeley and Toth use-wear analysis and said "see there is use-polish from cutting meat". Now I tend to say, "but there were more flakes used for cutting plant material".
On a slightly different tack, I think that one of the problems of looking at very early stone tool use may be the straightjacket of the classification "Oldowan". It does not make sense to me that the earliest use of stone tools should be expected to come in neat packages that archaeologists could label for the consistencies of flake production (and even sometimes label as a stone "industry"). I think this is a problem caused by the methods of archaeology. In any case, one of the things I enjoyed about writing the paper with Bill McGrew was that we ended up saying that, using the same criteria by which he had tried to evaluate the "cultural" status of the grooming hand clasp, we might not conclude that the earliest stone knapping was "cultural".
So the next question is presumably about the explanatory power of the different (untestable) hypotheses. And, as I say, I am now less interested in all those early apes than in the later stuff which has its own explanatory problems. But let us not get into that now, because I am meant to be writing something else.
Posted by: Iain | February 11, 2010 3:11 PM