Nefud For Thought: Scerri et al.'s Arabian Levallois Artifacts Give Us Pause To Reconsider Middle Paleolithic Typology

Far be it for me to downplay discoveries that have the potential to overturn long-standing misunderstandings about what went on in the past. On the other hand, I can't help but be excited when I see images of artifacts such as these, for what they imply about the bipedal apes that made 'em.

From Scerri et al. "Middle to Late Pleistocene human habitation in the western Nefud Desert, Saudi Arabia," Quaternary International, available online 8 October 2014.

I call your attention to object number 1. As you can see, it's described as a "Centripetally prepared preferential Levallois core," as is object 2. Object 3 is a "recurrent centripetal Levallois core," 4 is a "Single platform core," 5 a "bidirectional Levallois point core, 6 and 7 "discoidal cores," 8 another "single platform core," 9 a "multiple platform core," 10 and 11 are "bifaces." [BT dub, gotta give the authors credit for not referring to 10 and 11 as hand axes, since that's what they, evidently, are, and would normally be called that in run-of-the-mill Middle Paleolithic scholarship. O' course, they do identify similar objects as hand axes elsewhere in their paper—I guess maybe these two weren't sufficiently 'well made' or pointy enough to make it into that category. In that case, one wonders why they weren't treated as hand axe 'rough-outs' as others have done. Somebody stop me!]

What I'm seeing here could imply much more than what Scerri et al. are reporting—that these Arabian Peninsula Middle Pleistocene assemblages are evidence for multiple demes spanning tens of thousands of years in MIS 5, the last interglacial—including anatomically modern Homo sapiens from northeastern Africa and Homo neanderthalensis from southwestern Asia.

I think the authors are missing something about the size of these artifacts. Here's a close-up of number 1, with some everyday objects for comparison. Yep. Those are a One Pound coin, a Tooney, a Sacagawea dollar, and a 2 Euro coin.

Yet, despite its size, Scerri et al. describe this fragment of rock—barely larger than pocket change—as a "Centripetally prepared preferential Levallois core." It sounds impressive! It is impressive! If it's what the authors' claim, this little beauty could be evidence for a group of bipedal apes with hands smaller than a five-year-old's! Either that, or this so-called Levallois industry is just that, a three dressed up as a nine. After all, could any of these pieces actually be Levallois cores [which, forgive me, perhaps I've missed something all along, but, I thought a Levallois core was something that was being prepared for the final removal of a flake of predetermined shape]? Give me a break!


Object number 3 is an even more impressive piece when you consider that it's a "recurrent centripetal Levallois core." As so many of you already know, I'm not a lithic analyst. But I think that means—unlike number 1, this has more than one flake scar, implying more than one flake removal in preparation for that magical, mystical flake of predetermined shape, which, equally mysteriously, was never removed. So. When is a Levallois core not a Levallois core? And why were all of these not taken to the next stage, according to [the conventionally wise construct of the] plan?

For my part, I don't know why we just can't use the old Bordesian typology, illustrated below. In that case number 1 wouldn't even make it as a Levallois core, and, at best, number 3 would be a "Classic." A classic it be, for sure! Either way, given their size, any flake of predetermined shape that a bipedal ape hoped to remove at this point in the reduction sequence would either be doomed to failure, or so small as to have been useless for any function more adaptive than cleaning one's fingernails. The same goes for the rest of 'em. And for any inferences that they can milk out of these bit of rock, however they want to describe 'em, and regardless of how many others in our field accept their inferences. [But then, that's why I'm here, in my metaphorical pajamas in my metaphorical (dead) mother's basement, bashing out this piece of uninformed criticism.]

Nevertheless, if these little bits of stone can be described in this fashion, and yet be, to all intents and purposes, useless as Levallois cores—in the original sense of the type—what does it say about all of the grown-up 'cores' that we're told were being shaped for the purpose of removing a flake of predetermined shape?

Let's face it, it's easy to recognize a Levallois core after that flake's been removed. Number 5, above, is one such example—mostly because the central flake had a point. It takes a real expert to recognize one that never got that far! Unless, of course, those final flake removals weren't, after all, the predetermined end product of the presumed process.

Many times before I've trotted out the Levallois cores from Douara Cave as evidence for the fallaciousness of the presumed Levallois technology. But it won't hurt to do it again.

Levallois cores from Douara Cave (Credit Akazawa in Suzuki and Takai 1974).

I've outlined in red the final flake removal on these Levallois cores. Can we not agree that if their final shape was 'predetermined' there's nothing here that would fit, without considerable massaging of reality, in Bordes's original—and highly idealized—classification of Levallois flakes, which you see above.

I'd be very happy to throw out the whole Levallois technique baby with this Arabian Peninsula bath water.

I'll say it again, I'm not a lithic analyst. If I were, and if these rocks from the Arabian Peninsula were what the authors said they were, and if I believed them, I'd consider jumping on their bandwagon of desert archaeology and riding it as far as I could on the road to academic fame and fortune. But I'm not. And I don't. And I won't be joining them on their—obviously very prestigious considering the number of papers they're publishing and in what august scholarly journals they're publishing them—bandwagon.

I'm outa here.

Taxi!

Well, Duh! The Phrase, "Goes Without Saying," Comes to Mind Upon Reading Brown et al. (2013), "Site Distribution at the Edge of the Palaeolithic World: A Nutritional Niche Approach" [Where Else But In PLoS ONE?]

Major. Major news emerging from PLoS ONE this week! Get a load of this.

Brown AG, Basell LS, Robinson S, Burdge GC (2013) Site Distribution at the Edge of the Palaeolithic World: A Nutritional Niche Approach. PLoS ONE 8(12): e81476. doi:10.1371/journal.pone.0081476

Unlike so many papers that have been 'reviewed' at The Subversive Archaeologist, this one doesn't involve the authors taking a logical pratfall. Instead, Brown et al. offer us a statement of the obvious—you know, something along the lines of 

“Who shot him? I asked.
The grey man scratched the back of his neck and said: Somebody with a gun.”
― Dashiell Hammett, Red Harvest

Don't worry, guffawing is an appropriate response—both to the Hammett quote and to Brown et al.'s game[not]changing research findings. And, I'm not the only one who felt like mocking Brown et al.,  or feigning horror when I encountered the paper this morning—just look at what greeted me as the article was loading on Safari. 

[Just look at the photo, Dear. The photo! Not the rest of the ad!]

My analysis of this latest palaeoanthropological revelation from PLoS ONE will be very brief. So, before I proceed to expose yet another PLoS ONE howler, I'm gonna take a few minutes of your time to share an instant classic, courtesy of YouTube. [Apologies to my friends who might not be so fluent in English that this performance is an auditory blur—never mind, I think the parody is just as good without the sound.]  



Thanks to ID for thinking of me when he espied this gem.

Now, back to today's episode of "The Subversive Archaeologist Show."

See if you agree with me. It's PLoS ONE—open source, free—so there's no excuse for not looking at the paper with your own critical eye. I can't help but conclude that there's no "original contribution" here, unless you consider coining a new phrase reason enough to accept a paper for publication. [To be fair, the authors do introduce a novel analytical term—nutriscape—but I'm not sure it rescues this paper from the oblivion it truly deserves.]

Forgive me if what I'm giving you is oversimplified. Regardless of the hard work that went into the paper, the conclusions don't repay the effort. So, let's have a look at what the paper says of itself. Direct quotes will do nicely to illustrate the nature of this PLoS ONE article. First

During the last four interglacials the . . . richest Palaeolithic sites in terms of biface densities is [sic] strongly biased to the lower reaches of river valleys and sites which were above [Natural Tidal Limit] but in proximity to tidal rivers and estuaries. 

Let's see . . . In the real world [as opposed to the Bizarro world the authors apparently inhabit] those sites couldn't have been anywhere else BUT above the Natural Tidal Limit! That's this paper's first instance of stating the obvious. It's not the last. OK. What about their idea to use the ecological circumstances of Middle Pleistocene sites to say something general about the behaviour of the bipedal apes that left their traces at those sites? 

First you and I must invoke the usual caveats having to do with visibility and the preferential choices that palaeoanthropologist make as to where they will undertake their research. You know. The sites we choose to work should be comfortably close to a bar or public house, not too far from centres of culture, and not so remote or inaccessible that we spend all our research funding just getting to and from the site. It's well known that what palaeoanthropologists have to-date observed could be biased in untold numbers of ways, in turn biasing the authors' 'dataset' and thus their analysis. Even if you ignore those two sources of bias, in the quote above the authors are inadvertently proclaiming their own biases [or the blinders/blinkers that they are wearing] when they say that their 'data' are strong. 

Glacial geomorphology provides a perfect example of the possible biases at work in patterning the 'data' that Brown et al. rely on. During interglacials, global temperatures are warm, arctic and antarctic ice sheets melt, and sea levels rise. During glacials, more of the Earth's water ends up trapped in the ice sheets, and sea levels fall. In each of the interglacials covered in Brown et al.'s paper, sea levels would have been as high as, or higher than the present day. Okay, SA. What's your point?


Okay, smarty-pants, what happens to rivers as the world's oceans regress? South of the ice sheets, all things being equal, rivers begin to downcut and continue to do so until sea levels reach their lowstand. This is a time-transgressive process that, in more northerly latitudes,  proximity to the expanding ice sheets determines how deep and for how long a river will continue to downcut, or, for that matter, continue to flow. Brown et al.'s site sample is derived from the major river valleys of what's now southern England and northern France, which would have been equally affected by climate. So, to the extent that these northern rivers could downcut, they would have done so, in equal measure, all things being equal [once again] [geomorphically speaking]. 

What of it? Who cares? We do, of course! Because, in the study area during glacial maxima, much of whatever bipedal apes left behind on or near a river's floodplain would very probably have been disturbed or eroded completely, either by the downcutting stream or by mass wasting of the new valley's sides due to the river downcutting in unstable, unconsolidated sediments. Have a look at the two diagrams I've just spent about four hours crafting. [A pitiful performance, I'll admit. But at least this time I didn't breach copyright!] 

Sure. Sure. I know. I know! Each river is unique, sacred in its oneness. But, in general, these are the two sedimentary regimes that help me to think about the Middle Pleistocene archaeological record in the area that Brown et al. have dealt with—what part of the record was [and wasn't] or might have been 'lost' to glacial geomorphic processes. As you can see from the two cartoons, we palaeoanthropologists of northwestern Eurasia are mightily lucky that the most recent glacial maximum was less severe than the previous. Otherwise we might never have discovered the presence of Middle Pleistocene bipedal apes in areas near the great ice sheets.

'Kay. So. What now? Now that we've dealt with the problematic 'database' that these authors use to 'analyze' some sites and niches, let's have some fun.

Getting back to where we started. Remember that the authors have identified some salient points about Middle Pleistocene archaeological sites.

Location and topography of a bunch of Middle Pleistocene bipedal ape sites in southern England (top land mass), and northern France (bottom land mass). From Brown et al. (2013).

In their own words

[These places afford] access to water, safety from predators, lowest river crossing points (natural rivers are shallow and frequently anastomose in these reaches facilitating crossing)

River crossing points? Have they ever sashayed sur la Seine? Ventured to cross the Volga? Tip-toed across the Thames? They're joking, right? I know some have claimed that Homo erectus could make a boat. Likewise the Neanderthals. Really, though, there's not a scrap of evidence to support such arm-waving. But a boat would have been needed to ford most of streams in their analysis. [And they never explain the whole predator thing.]

and food resources. 

Mustn't forget food resources. Well, duh! Why would they expect to find bipedal apes somewhere there wasn't any food? Never mind. Brown et al. go to great lengths [no doubt at much expense of time and treasure] to classify the ecosystems in which these sites are found, and to judge them on their ecological merits.

In the above image, you see an encapsulation of Brown et al.'s ecological analysis. It emphasizes that, for Middle Pleistocene two-leggers, most of life's necessities were to be found near the rivers, and not the uplands. There's really nothing new, or even elegant about this inference. It's been the same story since time immemorial. Or, to use a less hackneyed expression, for effing ever! The key is "Location, location, location."

ecological classification . . . shows a marked potential locational advantage for floodplain zones as opposed to the forested slopes, plateaus and even clearings.

Sorry. I'm having trouble making sense of this phrase. I guess it means that, ecologically speaking, the sites used for their analysis were where the food was. Should this surprise us?

It is argued that this advantage may have included access to plants and animals which provided both essential energy and macronutrients but also critical micronutrients which maintained population health and maximised reproductive success and may have increased cultural complexity . . . .

Wow. There's a mouthful. *cough* Are we to imagine that the two-leggers chose to hang out where they could score the best micronutrients? Whether or not they did, they certainly didn't know they were increasing reproductive fitness by getting sustenance where it occured, instead of having to hike from a barren hilltop down to the river whenever the need to find food arose.

The upshot, according to Brown et al.? 

Such Palaeolithic diets . . . have been implicated in ‘healthy aging’, an emerging concept in evolutionary nutrition which has as its mantra ‘we are what we eat, but we should be what we ate.’ 

I'm thinking "Paleo Diet." They're joking. Right? Loren Cordain's Paleo Diet?

It is possible these locations were perceived as ‘healthy/good places’ to which hominins returned on a regular, and prolonged basis,

Like I said: whether or not these critters 'knew' what they were doing, as good mammals they would've figured out where the food is. Wouldn't they therefore tend to frequent such places [the way I used to frequent Joe's winery until the cash ran out]?

and may have been ‘marked’ by their assemblage of artefacts . . . .

Am I hearing right? Are Brown et al. suggesting that 'hand axes' were left strewn about for the same reason that a dog pisses on fire hydrants? And, while I'm at it. If the 'hand axes' were 'left' where the good food was, why would the two-leggers ever have left? At this point in the paper I'm starting to lose patience. But it gets even better.

A possible symbiotic interaction through niche creation on floodplains is postulated between hominins, horses, freshwater fish (particularly eels) and beavers. 

Wow! Brown et al. have discovered that bipedal apes were part of an ecosystem. It included horses and beavers, and eels [mustn't forget the eels, 'cause they're important for the Paleo Diet.] The authors imagine that these four life forms lived in symbiotic relations with one another. They don't say so, but surely they must be thinking of ‘mutualistic symbiosis’ as opposed to the other types of ‘symbiosis.’ Parasites, after all, have a symbiotic relationship with their host. Lichen is the result of a symbiotic relationship: it's an organism made of a fungus and a blue-green alga living off each other. The ecological relationships Brown et al. discuss are just that—ecological relationships—which don't need to be puffed up by calling them symbiotic. If the four organisms discussed in this paper are in symbiotic relationships, then so is every other organism on the planet!

[T]hese . . . important and revisited locations . . . support the contention that river valleys provided the nutrient-rich route-ways of exploration and utilization of Palaeolithic landscapes. 

I'm wondering if the beavers and horses knew they were living the good life in the best place on earth [the way Brown et al. propose was the case for the two-footed neighbours with their sharp rocks]. And what possible benefit could an eel secure by being eaten by a bipedal ape. I'm really lost, here.

Despite their best analytical efforts—and they're nothing to sneeze at, believe me—the conclusions that the authors make are of the "goes without saying" sort. It's a variant of "stating the obvious." Even though they did a lot of work to arrive there, I'm not sure the journey was worth it, for us, or for them. At best Brown et al. give you a good idea of what happens to a person's mind when they're brought up on a steady diet of palaeoanthropological myth. When they reach disciplinary adulthood, they're incapable of doing anything but re- re- re- reifying someone else's myth. You've heard of the expression 'standing on the shoulders of giants,' often used to express how science has a cumulative dimension? I think it's time for a new one. 

Whaddayathink of this? Instead of 'Standing on the shoulders of giants,' try 'Pissing into the wind while scaling the newly clothed emperor, trying to get to the top of the beanstalk to meet Grandma, only to find that you've been swallowed whole by the nefarious wolf.'

It's your turn. Meet me at Facebook and leave your suggestions. I'm off to tidy my micronutrient processing area.

Thanks for coming in today.
Sincerely,
W. Olf

SA announces new posts on the Subversive Archaeologist's facebook page (mirrored on Rob Gargett's news feed), on Robert H. Gargett's Academia.edu page, Rob Gargett's twitter account, and his Google+ page. A few of you have already signed up to receive email when I post. Others have subscribed to the blog's RSS feeds. You can also become a 'member' of the blog through Google Friend Connect. Thank you for your continued patronage. You're the reason I do this.

Absence of Evidence. Evidence of Absence?

At any point does absence of evidence stand as evidence of absence? This question has bothered me since the first time I heard it used in relation to the archaeology of former times. Well, the answer, realistically, is that there is a point. There is a point beyond which this aphorism no longer applies, in practical terms as much as in scientific terms! Furthermore, never accepting absence of evidence as evidence of absence, has, I believe, led many, many scholars to accept what amount to myths about past people and our hominid relatives and progenitors.
     First consider the Sasquatch. Ignoring the hoaxes and attempted hoaxes, most reasonable people consider the absence of evidence to be as good as evidence of absence. Likewise the Loch Ness monster. Likewise the allegedly dead Paul. Likewise Russell's teapot. The great 20th century philosopher Bertrand Russell once attempted to explain his atheism with a similar argument:

Many orthodox people speak as though it were the business of sceptics to disprove received dogmas rather than of dogmatists to prove them. This is, of course, a mistake. If I were to suggest that between the Earth and Mars there is a china teapot revolving about the sun in an elliptical orbit, nobody would be able to disprove my assertion provided I were careful to add that the teapot is too small to be revealed even by our most powerful telescopes. But if I were to go on to say that, since my assertion cannot be disproved, it is intolerable presumption on the part of human reason to doubt it, I should rightly be thought to be talking nonsense. 

Despite Russell's confidence, it's still the case that, with capable investigative techniques it may well be possible to confirm the absence of the teapot. So, I much prefer the following crystalization, because it not only illustrates my point, but also goes beyond the informal logic to the place we get to IF we persist in rejecting the absence of evidence as evidence of absence.

It's one of the reasons we can pretty much make the assertion, "There Is No Santa Claus" with quite a high degree of reliability, despite it being a negative. For it to be otherwise leads to a whole host of rather unlikely conclusions about the real world. --Wikipedia

And that's my point. When we believe, for example, that purposeful burial occurred in the Middle Palaeolithic, instead of treating it like the open empirical question is truly is, it almost always leads to 'a whole host' of ampliative inferences about the belief systems and cognitive abilities of the hominids that were putatively responsible. Belief in that activity among the Neanderthals almost certainly emboldened the excavators of the Sima de los Huesos to claim, blithely, that the deadfall trap in which they found Homo antecessor was a place of ritual disposal of that hominds' dead--hundreds of thousands of years before the emergence of H. neanderthalensis and the Mousterian archaeological record.     

     Sure, in purely objective terms, purely logical terms, it's impossible to say that absence of evidence will ALWAYS be evidence of absence. But in the real world, highly probable usually suits us as enough to conclude that something either exists or doesn't. For gawd's sake the sun just might not rise tomorrow! Who's to say? But, to all intents and purposes, it's a fairly safe bet. Why is it never the case in archaeology? When I ask, 'Where are the Middle Palaeolithic cave paintings? Where are the pre-Clovis sites?' I might as well be asking 'Where are the Leprechaun remains? Where the Fairy cities?' And yet, someone will always repeat the mantra: absence of evidence is not evidence of absence. 

     I hope I've managed to puncture, or at least to create a slow leak, in that argumentative balloon. Now you know that the absence of evidence is often taken as proof of absence. To persist in believing otherwise can easily lead to fanciful constructions of past reality, something I would hope we'd all prefer to avoid.
     

Iain Davidson Guest Comment: Seafaring Neanderthals?

I'm very pleased on this Friday to introduce the Subversive Archaeologist's good friend, Iain Davidson. He has a few words to say about the just-announced claim that Neanderthals were paddling around the Ionian islands in boats even before boats were invented. 
     But before I turn you over to Professor Davidson, I think it only host-worthy of me to give you a little bit of his background and, I suppose, his credentials for commenting on Ferentinos, et al.'s 'Early seafaring activity in the southern Ionian Islands, Mediterranean Sea', the latest bit of real archaeological science from the Journal of Archaeological Science's Very Serious Referees and Editors.
     Since before he and I became acquainted in about 1988, Iain and I have shared what I facetiously refer to as an 'intellectual pathology.' We both think that a lot of the claims for modern-human behaviour in the Middle Palaeolithic are misguided at best, misinterpretations for the most part, and, at worst, mythical.

Iain Davidson

     Iain has recently retired from his Professorial duties at the University of New England, in Armidale, New South Wales, where he plied his trade for several decades. His research and fieldwork have spanned the length and breadth of Australia, from the dream time to the European occupation. He has expertise in, among other fields, animal bone archaeology, taphonomy, lithic replication and lithic analysis (including having to do with the Near Eastern Middle Palaeolithic). He has published a good number of books, including a ground-breaking treatment of cooperative ties with Aboriginal groups. But the ones that are most closely connected with our favorite subject are one on the evolution of cognition and language and another on the relationship between lithic 'technology' and how we became human. [By the way, Iain, I had to put technology in inverted commas, because technology is a word that implies mindedness, and as you know, it's still an open question whether it existed throughout the history of stone artifact production.] If you check out the Subversive Archaeologist's Emporium, you'll see Stone Tools and the Evolution of Human Cognition, and a 'little' volume titled Human Evolution, Language, and Mind, which has been virtually ignored by all the wrong people, who seem disposed only to listen to Very Serious linguists like Steve Mithen. Iain and co-author William Noble got it right--I won't say the same for the competition. So, as you read Iain's comments, keep in mind that he's seen more lithics in situ, and studied the archaeology of Europe and Australia for more years than you and I've had hot dinners [that last bit might have been a slight hyperbole]. 


I received this from Iain this afternoon, after what was surprisingly little prodding. 

This is a very careful study of the bathymetry by a team well qualified to do that. I am less certain that the authors are on top of the issues about archaeology. But we are used to that by now. What can possibly be difficult about archaeology? So let us ask some questions.

Where are the artefacts? One of the island sites is said to be Lower Palaeolithic. My antennae immediately send me a signal. How are these artefacts being attributed? It is, by now, well established that it is not as straightforward as it once seemed to attribute surface finds to any of the subdivisions of the palaeolithic. What is needed is well-stratified finds from well-dated strata before we can go from 'There are some flakes here which do not look like Upper Palaeolithic blades' to 'These are Mousterian artefacts' to 'These artefacts date to the same date as Mousterian artefacts on the mainland' to 'These artefacts were made by Neandertals.'  In each case there is an inferential leap that is not substantiated. 

My question would be 'Are there no artefacts that look like these in any of the Upper Palaeolithic assemblages?' My guess is that there are, but that, as elsewhere, they have been ignored because of the dominant expectation that Upper Palaeolithic industries consist of blades. In the absence of even one illustration of artefacts it is impossible for anyone to know whether the attribution is reasonable. Even if the authors are qualified to be wedded to the inevitability of the Lower, Middle, Upper Paleolithic sequence, they need to establish the veracity of their claim that the occupation was genuinely a) Mousterian and b) of the same date as the Mousterian on the mainland and c) that only Neandertals made Mousterian assemblages (well, at least we know the answer to that--skeletally modern humans made Mousterian assemblages at Qafzeh in the east Mediterranean).

Finally, because this has been an exhausting week for silly claims about archaeology by people unqualified to make them, the maps are disturbing.    Figure 8 looks as if the short crossing between Lefkada and Kefallinia when sea-level was -120m was in the order of 2-3km.

Fig. 8. Palaeoshoreline reconstruction when the sea level was at —80 and
–120 m showing the most likely used short range route crossings to the islands from Middle Palaeolithic to Mesolithic. P: Peloponnesos, AA: Aetolo-Akarnania, IZ: Zakynthos Island, IK: Kefallinia Island, IL: Lefkada Island. [From Ferentinos, G., et al., 'Early seafaring activity in the southern Ionian Islands, Mediterranean Sea,' Journal of Archaeological Science (2012), doi:10.1016/j.jas.2012.01.032]

 The question we need to be asking is: what sorts of water crossing were possible for hominins at different times. I have always championed the importance of the sea-crossings that brought people to Australia. (And forgive me a moment's rage--there are some quite good sources about this published by people who actually know something about Australia. Why do European scholars think that the only good source is a European one?) But the point is that to make those crossings, watercraft did need to be constructed, because to get to Australia several crossings were needed and one of them was more than 70km. But the point I have tended to neglect is that there were also rivers to be crossed on the way: at very least the Nile, the Euphrates/Tigris and the Ganges. How wide were these crossings and how were they made? If we accept all of the other unsubstantiated assumptions involved in this paper, we may simply be looking at crossings that must have been commonplace at the time modern humans were moving out of Africa.

Iain Davidson, March 3, 2012.

He's wired into the comments, so fire away. And may the best paradigm win!

Journal of Archaeological Pseudo-science: Middle Pleistocene Mythopoeism from Kathu Pan 1

J. Wilkins, M. Chazan / Journal of Archaeological Science xxx (2012) 1-18

I don't know whether to scream or pull my hair out. So I guess I'll do both. 

Jayne Wilkins and Michael Chazan, Blade production ~500 thousand years ago at Kathu Pan 1, South Africa: support for a multiple origins hypothesis for early Middle Pleistocene blade technologies, Journal of Archaeological Science  39, 1883-1900, 2012.

The authors seem to think that they have indisputable evidence of a blade industry at give-or-take 500 kya (i.e. the product of Homo beforeneanderthalensis, no less). But when I went looking for their empirical basis I came up, well, virtually empty-handed. I won't go into the details of what they see as the implications of their findings, but I'm gonna reveal their findings for what they are--air and angels. In brief, my finding is that their findings are going to founder on the rocks of the Sea of Reality. Here's why.

     Wilkins and Chazan looked at 3,786 pieces of rock (out of the more-than 2 metric tonnes of lithics culled from the site!). Of the 3,786 bits, 955 were categorized as complete flakes and 972 were called blades. A 50:50 ratio of 'flakes' to 'blades' will be important later in this discussion. So, keep 1/2 and 1/2 in mind.

     The average length-to-width ratio for the blades is 2.5 (s.d. = 0.4). Therefore, approximately half of the blades are in the upper part of the range (i.e. 2.5:1 to 2.9:1) of length to width. The other 50% of the blades would just make it into the 'blade' category (i.e. between 2.0:1 and 2.49:1). Given that a) the minimum ratio to qualify as a blade is 2.0:1, b) the mean is 2.5:1 and c) the standard deviation is 0.4:1, it's impossible to say on the basis of the date presented whether the distribution of 'blade' length to width is uniform, platykurtic, normal, or leptokurtic. That's a crucial datum, as you'll see in a moment. Nevertheless, it is apparent that the distribution is somewhat skewed toward the upper end, given that the actual range of 'blade' length-to-width ratio goes from 2.0:1 to 4.5:1, strongly suggesting that it's more platykurtic than not. 
     You see, a mystery as to the shape of distribution for 'blade' length to width casts a deep, dark cloud over Wilkins and Chazan's whole argument, because it's quite possible that the length-to-width ratio for the entire assemblage (i.e. flakes + blades) is uniform or unimodal, with a mean closer to 2.0:1 than 2.5:1. That would call into question the wisdom of creating the flake/blade cutoff in the first place. Actually, it would make it seem silly.

Once more, an example of how well-meaning archaeologists cherry-pick (never disingenuously) their assemblages for specimens that put their claims in the best light. And, correct me if I'm wrong, but isn't N technically a Levallois point and not a blade? I really, really like M. That must have been one fine flint-knapper to have prepared a core to take off that one at the end of the sequence!

     What of the complete flakes? Alas, Wilkins and Chazan provide no metrics for those flakes that had a length-to-width ratio of less than 2:1. However, I'll take my usual place on a limb. I think it's safe to say that the vast majority of complete flakes in any assemblage are at least as long as they are wide (i.e. >1:1). That would mean that most of the non-blade flakes in the Kathu Pan 1 sample are between 1:1 and 2:1 in a comparison of length to width. Therefore, when compared with the entire collection of 'flakes' and 'blades' the authors examined for this study, nearly 1/2 are just on the shy side of being blades. 

    On that basis alone, I'm willing to bet the farm that, were it not for the arbitrary 2:1 cutoff between flakes and blades, the complete flakes and blades would more than likely form a continuous and uniform distribution of length to width from near 1:1 up to 2.9:1 (with the rest of the range scattered with outliers). If that be the case (and neither you nor I have any reason to think otherwise in the absence of sufficient descriptive metrics in Wilkins and Chazan's article) it would be very difficult for the authors to sustain their inference that the blades they find at 500 kya, and in such abundance, are anything other than artifacts of the arbitrary line drawn between a 'flake' and a 'blade.' 
     If the authors had so much as a shred of evidence that there was preferential blade manufacturing going on at Kathu Pan 1, I'd very much like to see it. In fact, this observer wonders at some of the data presentation decisions the authors have made, such as presenting a histogram of the widths of their 'blades' rather than their lengths, and leaving out the metrics for the non-blade flakes altogether. [It was unfair of me to say this, but I didn't want to revise history by expunging the record. So, I'll leave it in as a sort of persistent mortification of the flesh The lacunae are mysterious, to say the least.]
     If my criticism has any merit, all of the additional analyses contained in their paper (i.e. core analyses and comparisons with other MSA assemblages) would add up to nothing. Chalk up another big miss for the Journal of Archaeological Pseudo-Science and its referees. Is it possible that they didn't ask to see the overall distribution of length to width for the entire sample to make certain that this article wasn't all about how many angels can dance on the head of a pin? Way. To. Go!
     At the outset I promised I wasn't going to say anything about the implications of a paper like this. What the Hell! I can't forbear saying something. Because, once a story like this gets into a refereed journal there are many impressionable minds that'll just consume it without looking closely, and the myth will just continue to grow. There are also those very serious archaeologists out there who're predisposed to expecting stories like this one. Any chance they're gonna be critical? Hardly likely. The referees who gave this paper a thumbs-up ought, truly, to be ashamed of themselves. The Editors of the Journal of Archaeological Science oughta be ashamed of themselves, too. One of them is Robin Torrence, who should know better. Elsevier, the publisher, ought to be asking why this paper was accepted when, presumably, the vast majority of submissions are rejected for better reasons. And then there's me. I'm certainly not ashamed to call a three dressed up as a nine just that. It's so hard to keep an open mind [as my well-meaning colleagues often counsel] when there's so much seriously specious argument about, so much patently silly empirical observation spread around. Whatever happened to critical thinking? Whatever happened to common sense? Oh, yeah, well, it's never been all than common.

Let Me 'splain Somethin' to You 'bout John Hawks, Svante Pääbo, and You, Lucy

I suppose I should just come out and say it, since there's no point in being coy. The now-irrefutable evidence that you and I share varying amounts of apomorphic genetic material with the Neanderthals does nothing to settle the question of whether or not the Neanderthals and we might have, could have, would have, or should have had offspring together. 
     No good. 
     Whatsoever. 
     And here's why.
     For a moment, put aside whatever 'feelings' you may have about the Neanderthals' cognitive abilities compared with those of you and me. 
     About 100,000 years ago, at Qafzeh Cave, there are skeletally modern humans. A geological minute later there are Neanderthals a few km down the road at Kebara Cave. These two morphotypes may never have set eyes on one another. But the overlap in their territories, whatever the reason, means that there's at least a good chance they bumped into one another. Which means that if they recognized each other as potential mates the strong likelihood is that they did the wild thing and had families.
     You can slice it and dice it, split hairs, and argue 'til you're blue in the face, but the archaeological traces associated with each of these two species leads to the  robust inference that they behaved in the same manner. They produced Mousterian assemblages at each site, with a Levallois facies. If we had never found the skeletal remains at Kebara or Qafzeh, we archaeologists would no doubt have reached the same consensus--that those traces were left by hominids that were, more or less, behaviorally and cognitively identical.
     As you're no doubt painfully aware by now, I have strong reservations as to the abilities of the Neanderthals, based on my 'reading' of the archaeological record. And, those of you familiar with my three (Yep, 3) solo publications will know that, when I speak of the cognitive abilities of the Neanderthals I'm also speaking of morphologically modern, but archaeologically identical, penecontemporaneous hominids such as those at Qafzeh. What many of you don't know is that, if asked, I would also include Homo sapiens idaltu, at 160,000 kya and any other shape of hominid that left a similar archaeological record, regardless of their epoch. 
     I'm an archaeologist with a deep knowledge of evolution, human and otherwise. I'm also equipped with a modicum of knowledge in comparative vertebrate paleontology, geomorphology, pedology, animal bone identification, interpreting animal bone from archaeological sites, vertebrate taphonomy, site formation processes, lithic analysis, and informal logic. But I'm still just an archaeologist when it comes to the Middle Palaeolithic. 
     And, until such time as it's possible to say that Broca's Area unequivocally demonstrates that the owner possesses the ability to read this blog, or that we're able to say that the FOXP2 gene unequivocally demonstrates that its owner possesses a similar ability, all that remains for anyone to use in understanding the abilities of those ancient hominids is the archaeological record. 
     Archaeologists are uniquely placed to interpret ancient behaviours from archaeological traces. Anatomists cannot. Vertebrate palaeontologists cannot. Geomorphologists cannot. Sometimes I really wonder if lithic analysts can. I am profoundly aware that my expectations and presuppositions of Neanderthal behaviour can clutter and colour my perceptions. That's why I concentrate so heavily on the physical evidence and its context, because that's the only way to move past my expectations in understanding the cognitive abilities of Middle Palaeolithic hominids.
     Along the way, if I find knowledge claims that don't stand up, or represent, merely, one alternative explanation for the archaeological traces under examination, I'm compelled to point that out. There are so many extraordinary claims in the literature of the Middle Palaeolithic that it would takes decades of work like mine to really put the feet to the fire of those who've come before. I simply can't stand by while the real howlers are allowed to remain in the archaeological corpus. 
     And you're here to observe me at it. 
     So, to get back to the genome data. I'm in awe of the biochemical wizardry that John Hawks, Svante Pääbo, and their extremely adept colleagues are demonstrating. Yet, their documentation of the degree of relatedness between modern humans and the Neanderthals, or the Denisovans, means only that we share a common ancestor with the ancestors of those groups. 
     I'm very proud to say that it's still up to the archaeologists, and they alone, to decide which Middle to Late-Pleistocene hominid morphotype or population gave rise to people like us, and when that occurred. As it was before the 1000 genome data became available, when it comes to Middle Palaeolithic hominid behaviour we have a lot of work to do before we've investigated every alternative explanation for each and every extraordinary claim that's made about that distant time.
     I'm gonna go back to that task now.

Of Birch-Tar Hafts and Caribou-Tibia Fleshers: Campitello Quarry and Old Crow Flats

All would-be subversives take note, regardless of your area or epoch of specialization. This article is about sedimentary context--association--and only nominally about the Middle Palaeolithic. Even if you're not someone who gets a kick out of interpreting site sediments, and prefers to leave that to the 'experts,' you'd be far better off sticking with this post because one day, sure as shootin', you'll need to have these skills under your belt lest you fall for the oldest geomorphological trick in Mother Nature's book.

     In 2001 Mazza et al. (2004) discovered some very interesting lithic artifacts in a galaxy far, far away the Campitello sand and gravel quarry, near Bucine, in Italy. One was half encased in birch tar, and bore the unmistakable negative impressions of the haft. Cool enough, you might say. Trouble is, the claim is that it's Middle to early-Late Pleistocene in age. More Neanderthal chemical engineering? Wait and see. 

[May I say that Marco Langbroek has been very kind in directing my attention to this find. The trouble with my having been inactive for so many years is that I've been unable to keep up with the primary literature. It means, simply, that I am reliant on my friends and friendly acquaintances to bring such material to my attention. In this case, Marco has set me something of a challenge, and has goaded me into trying to, as he puts it, 'explain this one away.' All I can say in response is, 'With pleasure!']

A tip of the hat to Marco Langbroek for making this image available to us.

Thus, the gauntlet is thrown down (a lot like the gloves in a hockey game, in actual fact, which is, as you know, the national sport of my home and native land, but which I never played). This'll be most difficult trial in the short tenure of the Subversive Archaeologist. 

     After sowing the seeds of doubt with respect to claims of Middle- to Late-Pleistocene birch tar from Inden-Altdorf, Germany (Pawlik and Thissen 2011), I should say at the outset that I've no quarrel whatsoever with the chemical characterization of the Campitello Quarry mastic as being that of birch tar. Mostly it's because the same chemist that organized the real chemical characterization of birch tar is a co-author on the Campitello Quarry paper. So, where does that leave the subversive? If ya can't fault the evidence, you might be able ta find fault with the context.

[In fact, the contrast between this claim from Italy and the one from Inden-Altdorf has made me realize that there are really only two primary ways that archaeologists can 'get it wrong.' First is in the interpretation of their observations, as I've argued was the case at Inden-Altdorf. The other is the context of the evidence. In the Campitello case, it's the context--the association of the artifacts with the surrounding sediments--with which I have a problem.] 

     I think the Italians were expecting a little flak on the matter of context. In the following quote from their introduction, you'll notice that they are quick to point out their biostratigraphic evidence, which they aver will corroborate the putative age of these objects.  

Elephant and rodent remains were exposed in November 2001 in a clay pit, Campitello Quarry, in the outskirts of Bucine, a small village in the southern part of the Upper Valdarno basin, on the left hydrographic side of the Arno River. … The bones were entombed in fluvial gravels and sands stratigraphically dated to the Middle Pleistocene. A more clear-cut chronological indication is given by the rodents which prove that the finds date back to a moment of the late Middle Pleistocene [emphasis added].

As I was reading along, as I'm sure you will, too, I noticed that the artifacts and Elephas remains were found in sediments first described as a 'clay pit,' then as 'fluvial gravels and sands,' and finally as the fluviatile, 'massive, grey-green sand' of the latest stratigraphic unit, the Monticello Succession of the Valdarno Basin. Here's a schematic cross-section of the Arno River Valley from the article.

I want to go here. Look at the name of the mountain range in the south!

This sedimentary context is one in which chronostratigraphic 'mixing' is not just possible, but likely. In this case, the most recent sediments are identified as 'flood-plain' and these form a terrace, capping the older sediments in a recently formed, deeply dissected valley system. These recent erosional features are illustrated by the narrow U-shaped voids that have exposed the stratigraphic sequence to varying depths across the Valdarno Basin.

     Such erosional gulleys and valleys are notorious in  archaeological lore because they're places where younger clasts can easily be introduced into older sediments, and be unrecognized as such by the excavators. In this case, the excavators arrived after some of the Elephas bones were discovered (presumably by workers quarrying for sand and gravel--a common enough occurrence in such geological formations), which means that, at least for those objects discovered during quarrying, ALL of the overburden had already been removed. The authors do not say whether or not the portion they actually excavated was taken from beneath 15 or so metres of more recent sediments. But you'd think they might have mentioned it if they did. 

     So, there's at least a possibility that the sand in which they excavated was not the sand that had lain undisturbed for upwards of several hundreds of thousands of years. Take a closer look at the Valdarno cross-section, which I've pumped up in the illustration below. Here you can see these U-shaped erosional gulleys, and you don't need much of an imagination to see how it's possible for items of any age to be introduced into what are much older sediments as these features evolve. Couple that possibility with the absence of any real contextual evidence (or published description) for what lay stratigraphically superior to the bone and stone remains, and you have a recipe for, at a minimum, serious questions about their true provenience(s).

By the way. The notation with respect to the Acheulean is only meant to convey the presumed age of the oldest artifacts found terrace-top. Everything up to and including yesterday is up there, too. 

     Luckily for us, the Mazza et al. article provides several clues that the bones and lithics were indeed introduced from younger sediments. The first of these is the grain size of the enclosing sediments, which is described as fluviatile sand in a point bar context. Any stream that is depositing nothing but sand at some point in its journey has long since lost the energy to transport larger and heavier clasts, such as Elephas bones and the relatively massive lumps of stone and tar. That said, a river laying down sand at a point bar still has considerable speed and transport capacity, even if it's bedload is well-sorted sand, which leads me to the second observation.

     The second clue that the tar-wrapped artifact may have been introduced from more-recent times involves its   preservation condition. According to Mazza et al. the bones and stones do not appear to have been entrained for long (i.e. no signs of rounding that would rapidly occur in an ongoing point bar context). How is it possible, then, that they were buried without any signs of having been entrained in such a fluvial context? Not very possible is the definitive answer. [I would hasten to add that it's just possible that they were purposefully buried in a river point bar by some obsessive-compulsive Mid- to Late-Pleistocene hominid. But I doubt it.]

     The third clue given in Mazza et al. is that the lithic artifacts are patinated. This implies a considerable time spent in the open (ask anyone). Again, this isn't what you'd expect on a point bar.

     The fourth clue that all is not as it should be is the context of the microtine fauna, described in this way.

[the microfauna were found] in a layer of fine sand, silty clay and thin laminae of organic debris, that coated the sand bed which contained the stone implements and the elephant skeleton [emphasis added].

Such sediments could NOT have been deposited in a point bar. Full stop. Unless, that is, the river suddenly turned into a basin in which water stood still long enough for the fines (i.e. clay and silt-sized particles) to settle out. Something just isn't right about the archaeologists' interpretation of the sedimentary context of these objects. There can be no doubt of that.

     Notwithstanding the fine work done by the faunal specialists in identifying the Mid-Pleistocene microfauna, or the chemical characterization of the birch tar, or the taphonomic study of the Elephas bones, there is nothing coherent about the archaeological context of these finds. Every aspect of the archaeologists' description contributes to the strong suspicion that the substantive finds are not all from the same time.

     To give you an example of how easy it is to get fooled by the complex depositional processes in geomorphic contexts like the Valdarno Basin, one need only recall the famous 'Old Crow Flats caribou flesher' that caused a big stir amongst Paleo-Indian archaeologists in North America and abroad in the late 1960s and on into the 80s. Discovered in a point bar of the Old Crow River, this caribou bone artifact was found associated with 25,000 year old animal bones. 

The same type of caribou tibia artifact as that found at Old Crow Flats (Illustration credit).

The following is a snippet of a synopsis of North American archaeology that appeared in Archaeology magazine in 1999.

In the summer of 1966, a paleontologist collecting fossils from along the Old Crow River in arctic Canada found amidst a jumble of bones from now-extinct Pleistocene animals a caribou tibia, its end carved into a toothed spatula. The mammoth remains found with the flesher appeared to have been flaked and fractured, like artifacts. The specimens were more than 25,000 years old, far older than anything then known from the western hemisphere. ...redated in the 1980s the caribou tibia flesher proved to be only 1,350 years old.

from David J. Meltzer, 'North America's Vast Legacy,' Archaeology 52(1), January/February 1999.

Those with long enough memories will bear me out on this matter.

     In closing, I'd like to offer a challenge of my own: that Mazza et al. subject a minute sample of the birch tar for radiometric dating--specifically radiocarbon. I'll bet my well-worn Marshalltown that it doesn't exceed the limit of radiocarbon dating, which, as most of you know, is (at the extreme end of extreme) not above 75,000 years, and is normally cited as give or take 50,000. Definitely not Middle Pleistocene, but could be Late. My guess is that it's no more than terminal Pleistocene or Holocene in age.

     *puff of smoke*