Saturday 31 December 2011

New Year's Eve in Surf City

Anybody else have to wait until the 3rd of January to get paid? I'm broke! I'm having to scrape day-old chicken fat off the cutting board, gently sautée it so as not to lose any of the goodness, and pair it with the reconstituted sauce from a long-empty can of baked beans that I bought on sale last week with what I could find in the piggy bank. Sheesh! 
     But, I'm goin' shopping on Tuesday night after work! My pockets'll be full of thin pieces of plastic, which I'll use with abandon. Don't read on if you can't stand the thought of good food just now. [I'm getting psyched.]

     Presenting: The Subversive Archaeologist's clickable dinner menu for Jan. 3rd through 7th.
Speargrass is too 'spensive this time of year, so it'll prolly haveta be broccoli, with pan-roasted fingerling potatoes.

Chili-Spiced Chicken Soup with Stoplight Peppers and Avocado Relish
This is a one size fits all soup. All it needs is a little corn bread!

Pasta Fagioli
Arthur Fonzarelli. Where are you now? I'll admit, Asiago is one of the more pungent toppers in the 'fridge. But it's soooo good.

Huevos Rancheros with Queso Fresco

The queso fresco makes this a meal. Bon apetit!

Lastly, a recipe of my own.
Smoky Slumgullion
Feel free to substitute at will, as long as it's fired or smoked.
     Champagne time. [Paid for it weeks ago, knowing I'd be stoney broke by tonight!]

Have a safe and pleasurable evening.
See you next year!

Friday 30 December 2011

Busy, Busy...

I'm very busy Holy Daying, which means I'm writing less. But I'm thinking more to make up for it! I'm looking forward to a new year of subverting conventional wisdom and pointing out the archaeological howlers as they come down the pike. In that vein, I've some New Year's resolutions. They'll take concerted research to bootstrap myself in a couple of empirical domains with which I'm unfamiliar. Sometimes I feel like Toad in The Wind in the Willows. You know, out for a drive in his roadster, drunk with power and careering off every fence post, cenotaph, and mail box in the countryside. Didn't Toad end up in gaol?
     But I digress. Back to the future. 
     I think there's something not right about the record of fire in the Middle Palaeolithic. But I'm neither a chemist nor a geologist, so wish me luck with that! I'm not sure, but we could be dealing with spontaneous combustion. Not the little old lady out shopping, X-files kind of spontaneous combustion! I mean the kind that happens in compost heaps and manure piles. I'm gonna need all the help I can get with that one!
     I'd also like to find someone--anyone--with data on the Neanderthal cribriform plate. I believe that knowing the dimensions of that structure will reveal much about the H. neanderthalensis olfactory sensitivity in comparison to that of modern humans. Iain Davidson put me on to an article published in the December 13, 2011 issue of Nature Communications, in which the authors make the claim that their
[t]hree-dimensional geometric morphometric analyses of endobasicranial shape reveal previously undocumented details of evolutionary changes in Homo sapiens. Larger olfactory bulbs...appear unique to modern humans.
The paper is 'Evolution of the base of the brain in highly encephalized human species,' by M. Bastir, A. Rosas, P. Gunz, A. Peña-Melian, G. Manzi, K. Harvati, R. Kruszynski, C. Stringer & J.-J. Hublin.
     That's a formidable cadré, and I'm probably in over my head, statistically speaking, having mastered everything up to, but not including multi-variate analyses in all their variety. However, the sense that I get from Bastir et al. is that they first 'normed' the data to avoid monitoring allometry, and then compared the derived metrics across hominid species. If so, it's probable that the absolute measurements would reveal a Neanderthal cribriform plate that's larger than ours. And, given the existence of research claiming that it is the absolute size of the cribriform plate that determines olfactory sensitivity in mammals, it might yet be possible to discover if the Neanderthals had a sniffer superior to yours and mine.
     I've written to the corresponding author, hoping to persuade him to pass along any hard numbers they might have acquired. Unfortunately I used my work email and the uni is closed until the 3rd of January.

     So, stick around. 2012 is gonna be interesting! [For me, if for no one else!]

Thursday 29 December 2011

Sibudu Redux: Sedges and Rushes! Oh, my!

[I'm re-posting this under the expanded title, on the assumption that the faithful might think 'Redux' meant 'more of the same.' Since this is a substantive addition to my earlier post, I want to make certain everyone has had a chance to see it. So, ahead to the pasture!]

I think that if I see one more headline screaming 77 kyr old mattresses, whether insecticidal or not, I'll come down with a bad case of hay fever. After I suggested an alternative explanation for the presence of leaf mats at Sibudu 'Cave,' Gerrit Dusseldorp left the following comment on SA: 
'I enjoyed the post, but ... I think you have missed an important part of the argument. Namely, the younger part of the bedding in the sequence ~58 ka consists of sedges (Cladium mariscus according to the paper) characteristic of wetland environments. They would have to have moved up from the river valley to the abri. Hence, your alternative scenario does not hold for these deposits.'
As you might imagine, I beg to differ. It is simply false to claim, as Wadley et al. do in the Science article, that  
Cyperaceae (sedges)...and Juncaceae (rushes)...are normally plants of wet habitats and could not occur naturally within the dry rock shelter.
They should have said 'a dry rock shelter.' That would have been a statement that could endure scrutiny. However, nothing says that the rockshelter has always been a place bereft of ground or surface water. 
     In fact, team archaeobotanist Robyn Pickering is careful to point out (and unable to adequately account for) the rather enigmatic, but nonetheless frequent occurrence and relative abundance of gypsum formation in the Sibudu sediments. According to the excavators, this mineral could not have remained in nodular form in the presence of significant moisture--it would have dissolved. Thus, they say, it's a dry place. True enough. But how did the gypsum form in a place too dry for it to degrade? Pickering suggests that at some time cool coastal mists may have reached as far inland as the rockshelter and produced the circumstances necessary for gypsum to form in the deposits. But really, gypsum needs the prolonged presence of soil moisture to form. It's an empirical question whether or not fog would do the trick. So I'd have to say that the jury is still out. Unfortunately for the defense team, several witnesses for the plaintiff have come forward who can explain the presence of gypsum, as well as the hydrophilic plants that are the cause of so much commotion. 
     I'd hasten to add, however, that although running water can be ruled out as a significant contributor or disturber of the sediments at Sibudu, the possibility of ephemeral ponding can not be so easily dismissed. As I pointed out in my first post on Wadley et al.'s claims, the east to west slope trend is downward toward the rockshelter wall throughout most of the sequence. And, although the north to south trend is also downslope, the lay of the land near the wall would not preclude accumulation of water at certain times, which would explain formation of gypsum and the presence of hydrophilic plants.
     How so? A watercourse flows nearby, the riparian vegetation of which would be a perennial source for seed. Indeed, sedge and rush seeds are found throughout the sequence at Sibudu. Even if standing water were fairly short-lived, you can't rule out germination and growth to maturity of rushes and sedges within the dripline of the shelter. Its aspect is westward--plenty of warmth and sun to nurture the growing plants. The hypothetical standing water would only need to have persisted for a couple of months to play host to a thriving, but spatially limited, community of rushes and sedges. As for these genera being unable to survive in a tenuous hydrological regime such as an ephemeral pond, there is reason to believe that the species involved may not require permanent or even abundant water to survive.
     In fact a quick search of my friend Google gleaned an interesting brochure published in September of this year by the Botanical Society of South Africa's KwaZulu-Natal Coastal Branch, a portion of which is reproduced below. It's a brief description of the Society's outing to the ocean-side sand dunes near Durban's Beachwood Mangroves Nature Reserve.
The beach and dunes revealed more common coastal species eg. ... Juncus kraussii
As an example, have a look at one natural habitat of J. kraussii in the photo reproduced below. J. krausii is found in abundance in the sediments excavated at Sibudu Cave.
Juncus kraussii at home in South Africa. Note the distance that these plants are removed from the nearest source of water. Granted, they may not grow to 1.5 m as their healthier neighbours nearer the water. But they seem to manage allright.
In the same brief web search that yielded information about the tolerance of rushes for less-than favorable moisture regimes, I managed also to discover the following about sedges, published by the South African National Biodiversity Institute.  
Many species [of Cyperaceae] are deciduous, and survive the unfavourable season as rhizomes, corms or tubers. Several species grow in semi-arid areas, and are able to survive periods of drought due to succulent, water-storing leaf sheaths. In arid areas many species have overcome the problem of temporary moisture (such as in pans) by becoming annuals, completing their life cycles in a month or two.
As I am not an archaeobotanist I'm unable to say whether or not the Cyperaceae found at Sibudu fall into the same category as the ones described above. However, I do think I've made it clear that there's evidence for considerable genotypic variation and phenotypic tolerance of less-than perfect growing conditions within the numerous different species of rushes and sedges that grow in the region, including the rush, J. kraussii, that was recovered at Sibudu.
     The question really comes down to one of probabilities. What is the probability that gypsum formed at Sibudu on account of fog? What is the probability that, over the last 77 kyr, ephemeral ponds or moisture catchments formed at times in the low-lying areas of the large rockshelter, and the normally water-loving rushes and sedges, whose seeds accumulated in the shelter in abundance, managed to eke out an existence, like J. kraussi in the Durban dunes? What are the probabilities? What, indeed?
[Addendum 2011 December 30: I've heard from Gerrit Dusseldorp, the worker who prompted me to extend this mattress critique. He says I've convinced him. One down. Untold hundreds to go!]

Touchstone Thursday: Margaret W. Conkey and Janet D. Spector's "Archaeology and the Study of Gender" (1984)

[If this post encourages you to read this article for the first time, the other readers and I would really love to hear what you think of it.] 

Article available online at 
It's difficult to imagine a more courageous and radical treatment of archaeological theory than 'Archaeology and the Study of Gender.' Margaret W. Conkey and Janet D. Spector's 'shot across the bow' of the archaeological establishment has every bit as much to say to the present generation of archaeological big-wigs as it did nearly three decades ago.
     As a male who has practiced archaeology on four continents and through four decades I can claim a certain amount of authority in saying that the message of this week's touchstone still generates venal back-room commentary amongst 'the boys' who have reason to think they set the agenda for 'the gals.' Indeed, the 'No Girlz Aloud' sign still hangs on the clubhouse door. I have trouble believing that it is simple sexism. Instead, I believe that out-and-out misogyny slithers along in the social and political negotiation of power in archaeology, at least in the English-speaking world.
     To say that the cogent empirical argument presented in 'Archaeology and the Study of Gender' met with vilification would be a ludicrous understatement. I've heard Conkey and Spector [and their ilk] referred to in the worst possible ways imaginable. And I have to ask 'Why?'
     Why would a community of literate and self-described 'objective' males find Conkey and Spector's words so despicable? Why would that same group of males greet this thoroughly empirical study of the status quo with base behavior? It's not as if they needed to worry about the study of gender in archaeology. How could it possibly have posed a threat to them? It couldn't. No, I think there's been a fundamentally personal and emotional reaction on the part of each male who ever found fault with or had disdain for 'Archaeology and the Study of Gender.'
     And I think I know the reason. I think I know because I've many times observed the enmity that many male archaeologists have for the females in their midst. Take anything that Conkey and Spector relate about the male stance with respect to women, both within and outside of archaeology and double it. Then double it again. Then you might be getting close to the truth.
     It has nothing to do with research agendas. It has little to do with serious criticism of the promise for an archaeology of gender. Instead, I believe it has everything to do with power and access to power, and how it is meted out. I'm not positing a revolutionary insight. Others have no doubt argued in a similar vein. So, I hope you'll forgive me if I say anything that you may have heard before.
     In 1967 a presidential executive order amended affirmative action legislation in the U.S. to include sex. With academic positions becoming fewer and fewer by the 1980s, males were beginning to speak of the 'pinch' of affirmative action. Even though there had been women in the field for generations, as long as they were a small minority it had always been possible to ensure that they never achieved positions of power, or 'took away the job' of a prospective male academic. 
     And it's not as if affirmative action provided women with instant access to power, or even in the short term. And it certainly never provided direct access to power at any time. Thus, in reality, the 'boys' weren't in any danger of losing their grip on power. Nevertheless, in the 1980s every time a woman was successful in her job search, there was an immediate and visceral response on the part of the males--those who'd competed alongside the woman, and those already safe in their positions as her new colleagues. Their response was simple. It was misguided. It was fundamentally hateful. And it was this: 'There goes another affirmative action hire.'
     I'd like to say that Conkey and Spector's article began a slow erosion of androcentrism in archaeology. I'd like to be able to say that their work is, in the present, a quaint anachronism. Sadly, it is neither.

Wednesday 28 December 2011

Winter's Dearth

With so much to comment on in the last few weeks, I guess it's only natural that there should be a lull at this time of year. No spectacular, media-worthy claims. No ancient thises or thats for The Subversive Archaeologist to pooh-pooh. 
     I'm watching the news ticker go 'round and 'round, and the best I can find is a socialist web-zine that's using all of the recent claims about Neanderthals to argue that for several hundred thousand years we've been less guided by our genes than by our awareness of the (mostly) arbitrarily assigned social meaning of blue jeans. 

By Philip Guelpa 
27 December 2011

I'm guessing that the purpose for putting this on the World Socialist Web Site (published by the International Committee of the Fourth International) is that the social Darwinists (read biological determinists) are still haunting the consciousness of the Darwinian socialists. 
     Go ahead. Have a read. It's good propaganda for the claimed existence of Neanderthal culture (and we all know how truthful propaganda can be).

Tuesday 27 December 2011

Scrooge's Take-Home Message: Everyone is Everyone's Business!

For the 99%, which includes most of us. 
From A Christmas Carol by Charles Dickens
They were portly gentlemen, pleasant to behold, and now stood, with their hats off, in Scrooge's office.  They had books and papers in their hands, and bowed to him.
"Scrooge and Marley's, I believe," said one of the gentlemen, referring to his list.  "Have I the pleasure of addressing Mr. Scrooge, or Mr. Marley?"
"Mr. Marley has been dead these seven years," Scrooge replied.  "He died seven years ago, this very night."
"We have no doubt his liberality is well represented by his surviving partner," said the gentleman, presenting his credentials.
It certainly was; for they had been two kindred spirits.  At the ominous word "liberality," Scrooge frowned, and shook his head, and handed the credentials back.
"At this festive season of the year, Mr. Scrooge," said the gentleman, taking up a pen, "it is more than usually desirable that we should make some slight provision for the Poor and Destitute, who suffer greatly at the present time.  Many thousands are in want of common necessaries; hundreds of thousands are in want of common comforts, sir."
"Are there no prisons?" asked Scrooge.
"Plenty of prisons," said the gentleman, laying down the pen again.
"And the Union workhouses?"  demanded Scrooge.  "Are they still in operation?"
"They are.  Still," returned the gentleman, "I wish I could say they were not."
"The Treadmill and the Poor Law are in full vigour, then?"  said Scrooge.
"Both very busy, sir."
"Oh!  I was afraid, from what you said at first, that something had occurred to stop them in their useful course," said Scrooge.  "I'm very glad to hear it."
"Under the impression that they scarcely furnish Christian cheer of mind or body to the multitude," returned the gentleman, "a few of us are endeavouring to raise a fund to buy the Poor some meat and drink and means of warmth.  We choose this time, because it is a time, of all others, when Want is keenly felt, and Abundance rejoices.  What shall I put you down for?"
"Nothing!" Scrooge replied.
"You wish to be anonymous?"
"I wish to be left alone," said Scrooge.  "Since you ask me what I wish, gentlemen, that is my answer.  I don't make merry myself at Christmas and I can't afford to make idle people merry.  I help to support the establishments I have mentioned -- they cost enough; and those who are badly off must go there."
"Many can't go there; and many would rather die."
"If they would rather die," said Scrooge, "they had better do it, and decrease the surplus population.  Besides -- excuse me -- I don't know that."
"But you might know it," observed the gentleman.
"It's not my business," Scrooge returned.  "It's enough for a man to understand his own business, and not to interfere with other people's.  Mine occupies me constantly.  Good afternoon, gentlemen!"

Deflating Man the Fat Hunter: Brian Switek Saves Me the Trouble

A fellow traveller named Brian Switek, who blogs as LAELAPS, has a thoughtful piece about the extirpation of Homo erectus and elephants in the Levant 200 to 400 kyr ago. He has saved me the trouble! Thanks, Brian!

Saturday 24 December 2011

Posting Over the Holidays...

I expect that most of the ever-faithful readership of The Subversive Archaeologist will be increasingly engaged with family and friends over the next couple of weeks. I hope none of you has to endure unpleasant company in keeping with the spirit of the season. I intend to spend as much time as possible this season enjoying pleasant spirits! For that reason alone I should probably try to limit my posting--wouldn't want to say anything that I'd regret the next morning. Or the next year, for that matter! 
     As a gesture of gratitude for your continued support, I'm giving each and every one of you unfettered access to the SA archives over the holidays! Free. Gratis. 
[Yeah, well, I'm a bit light in the purse this month. So, as much as I'd like to smother you all in seasonal plenty, it's the best I can do. At least my gratitude is plentiful and sincere!]
Happy Holidays, everyone! Merry Christmas! Good Yule! Enjoy the Festival of Lights. Go watch the Alistair Sim version of 'A Christmas Carol' or 'It's a Wonderful Life.' Stare at a picture of Stonehenge. I'm gonna listen to Barbara Streisand singing Christmas songs, and practicing the horizontal handstand on my new Festivus pole!

Thursday 22 December 2011

Touchstone Thursday: Alison Wylie's 'Archaeological Cables and Tacking: The Implications of Practice for Bernstein's Options Beyond Objectivism and Relativism.'

Among the memories of a life spent learning--much of it having to do with archaeology--Alison Wylie's 'Archaeological Cables and Tacking: The Implications of Practice for Bernstein's Options Beyond Objectivism and Relativism' stands apart from all the other papers I've read. I don't mean that it's the best ever (although it's probably in the top 25); just that it, alone, reaffirmed my confidence in the 'scientific project,' and at the same time helped me to avoid the vertiginous feeling of helplessness that I had developed in response to radical post-modern anthropology. 
     In the mid 80s there was much feminist and post-modern criticism of science, because its practitioners, besides being majority male, were believed to be hopelessly mired in their cultural and social worldview, and that 'doing' science didn't privilege a knowledge claim over any others in the realm of knowledge making. The writings of Derrida and Foucault were on everyone's mind, and I was very uncomfortable with the notion that scientific knowledge was no more credible than, say, personal or religious knowledge. I was hearing 'science is dead' more than I could stomach. I wasn't ready for a world in which the phrase 'anything goes' accompanied the question of choosing between competing explanations of past culture change.
     I was very fortunate that my graduate advisor, Meg Conkey, was friends with Alison Wylie, and found some money to bring Alison to Berkeley for a semester in 1989. Wylie's Ph.D. dissertation had been an examination of the tension between the stated goals of processual archaeology and the reliance on an account of science that had its roots in stringent empiricist philosophy of science. Put succinctly, coming to know the archaeological past--i.e. something that literally does not exist--was effectively ruled out by the view of science known as Logical Empiricism (AKA Logical Positivism) and the nomothetic-deductive method championed by Lew Binford and others. In 1989 Alison had published a string of articles that, for me, made sense of many of the debates that had riven archaeology in the 1970s and 80s. They included
An Analogy by Any Other Name is Just as Analogical: A Commentary on the Gould-Watson Dialogue, Journal of Anthropological Archaeology 1 (1982): 382-401. [Which 'reinstated' ethnographic analogy as one path to the past.]
Epistemological Issues Raised by a Structuralist Archaeology, in Symbolic and Structural Archaeology, edited Ian Hodder, Cambridge University Press, Cambridge, 1982, pp. 39-46. [Which calmly extolls the virtues, and underscores the shortcomings, of Structuralism as a methodological framework for doing archaeology.]
The Demystification of the Profession, in The Socio-Politics of Archaeology, edited by Joan M. Gero, David M. Lacy, and Michael L. Blakey, University of Massachusetts, Anthropology Research Report Series #25 (1983): 119-129. 
Between Philosophy and Archaeology, American Antiquity 50 (1985): 478-490.
Putting Shakertown Back Together: Critical Theory in Archaeology, Journal for Anthropological Archaeology 4 (1985): 133-147. [Which took a sensible approach to the search for ideology in archaeology.] 
The Reaction Against Analogy, in Advances in Archaeological Method and Theory, Volume 8, edited by Michael B. Schiffer, Academic Press, New York, (1985): 63-111. [Which elucidates the way that archaeological inferences are really made.]
In seminar, Wylie took us through her thinking about archaeology, its scientific basis, its epistemic limitations, its ultimate goals, and its relation to the latter-day critiques from Marxism, Feminism, and Post-Modernism.
     This Thursday's Touchstone showcases Alison Wylie coming to grips with the radical post-modern critique and, using a traditional empirical approach, illustrates [among other issues] why the post-modern critique can be seen to shoot itself in the foot, leaving room for what's called a 'mitigated' objectivity as the goal of an empirical science.
     I can't recommend this work in strong enough terms. It vanquished my fear of post-modernism, once and for all. And it can do the same for yours [if you're predisposed in that direction].

Wednesday 21 December 2011

One Mammoth Steppe Too Far

     The old bull is thirsty. And even though snow lies everywhere on the ground, there's little to drink. But he knows a place where the water collects--a shallow basin on an otherwise gently sloping hillside. He can smell the rot as he approaches the pan. Others of his kind, young and very old, come down to drink and some never make it out of the gumbo that underlies the water. Likewise many of the other four-footed beasts. 
     It's late summer on the steppe...if you can call freezing night-time temperatures 'summer.' The pool is much shrunken after months of drought, and this year's dead dot the bare earth. A tentative step tells the old bull that the bare ground is firm. His 8 tonnes edge onto the pan toward the remnant pond, shimmering in the raking sunlight. Without warning, the frozen crust gives way. His left front foot sinks to the knee and his bulky torso lurches to the left driving his leg all the way into the cold clay. Every subsequent movement mires him deeper, and soon he's hopelessly trapped. 
     The rest of this dance of death takes many days, while he slowly starves to death. If he's lucky he'll be spared the horror of being butchered alive by hyaenas or those two-legged creatures with hands like knives...

National Geographic photo of a pan in Zambia during a drought. This helpless elephant was fortunately rescued by game wardens. Most aren't so lucky.

I thought that a word painting would help to explain the basis of my critique of Demay, Péan and Patou-Mathis's 'Mammoths used as food and building resources by Neanderthals: Zooarchaeological study applied to layer 4, Molodova I (Ukraine).' Using faunal remains and spatial data, this paper promises to reveal how the two-legged creatures acquired the elephants and how they might have used them. They aim to 'test the hypothesis of a non-food use of mammoth resources by Neanderthals, especially as building materials.'
     Although the authors mention Gary Haynes's work on elephants and the fossil record, they evidently missed the bits about elephants getting mired in clay at water holes, and the taphonomic consequences. 
Click on the diagram to enlarge. Geological section of Molodova I site reproduced in Demay, Péan and Patou-Mathis (from their Fig. 2).

My attempt to make the vertical and horizontal scales equivalent in the schematic geological section of Molodova I site reproduced in Demay, Péan and Patou-Mathis (from their Fig. 2). It just about halves the slope gradient. Remember, too, that this is a schematic, and the reality would in all likelihood be very different.

As can be seen in the schematic representation of the local stratigraphy, shown above, the Moldova I excavations would have been a prime area for the formation of pans. At the toe of a river terrace the gradient is low, allowing basins to form, and the long upslope would be a ready source for the fine particles that create an elephant death trap. 
     The description of the excavated sediments are clear evidence that the site was, for quite some time, a low spot that collected water and fine sediments. I'm not sure what 'scattered soil' is, but it's likely that the authors were trying to say something like 'disturbed sediments.' I'd expect considerable 'disturbance' in such depositional circumstances. Imagine the 'disturbance' that could be wrought by an 8 tonne pachyderm in a quagmire full of the carcasses of newly deceased critters, and the skeletal remains of the long dead. 

Schematic diagram of Moldova I stratification. Layer 4 contains the faunal remains discussed in Demay, Péan and Patou-Mathis (after their Fig. 3).
Apparently clay is in abundance throughout the sequence , as shown in the schematic stratigraphic drawing above. Clay collects in basins of water. Clay, when wet, is gooey. And as you've seen at the beginning of this post, it's common for animals, large and small, to come to grief in such geomorphic features. 
     It's astonishing that the authors wouldn't have considered the geomorphic context before they settled on hunting as the reason for the animal bone accumulation at this locality. And, if they'd been aware of the true nature of the faunal accumulation they would probably never have suggested that the 'circular' area was a structure and not just the natural, expectable result of butchery, in place, of very large, mired animals.
     I think that probably suffices to explain the faunal and stone artifact accumulations in layer 4 at Moldova I. With regard to the claims made based on bone modification, one can only say that the evidence provided in the paper is less than persuasive. Their Figure 12 presents photographs of modified bone and ivory. All are equivocal, on the evidence, and I'd be very surprised if the authors could produce additional observations that would make these claims more believable.

Click on the illustration to enlarge. Text of caption taken from Demay, Péan and Patou-Mathis (their Fig. 12) [italics mine rhg]a) Butchering cutmarks on a mammoth rib; b) Fracture impact on long bone diaphysis of mammoth; c) Reindeer antler probably used as percutor; d) Sharp grooves on a mammoth tusk; e) Series of parallel sharp grooves on the glenoidal cavity of a mammoth scapula; f) Series of parallel sharp grooves on a mammoth innominate (Photo: S. Péan).
The readership can question my authority in all of these matters. It wouldn't bother me and it wouldn't surprise me. However, in the case of the bone modification I'm pretty sure that Gary Haynes and Diane Gifford-Gonzalez will back me up. The two grooves in image 'a' could well be stone tool cut marks. They could also be the result of any hard, sharp object grazing the bone in the dynamic context of the water hole. One would need to examine the 'scar' itself to see the tell-tale marks of a flake of stone or a biface. 
     The semi-circular modification in 'b' might be the result of a hominid trying to enter the diaphysis to extract the marrow. However, this removal lacks the crushing that usually occurs on the diaphysis at the point of percussion, which leads me to conclude that the authors' claim is more wishful thinking. 
     The image in 'c' is so poor that it's impossible to tell why the authors claim that this is a percussor for stone-tool making. 
     The two sub-parallel fine grooves in 'd' might be stone tool cut marks were it not for the bone chip removed alongside the one on the right. This is more than likely a pair of carnivore tooth drags. On the other hand, why would a self-respecting carnivore spend time on a tusk, unless it was the part covered with yummy soft tissue. No help from the authors here. 
     All of the marks in 'e' are as likely as not carnivore tooth mark. They look nothing like stone tool cut marks.   
     Finally, the fine, parallel striations in 'f' are classic trampling damage. At this scale it could well have been the foot of an 8 tonne elephant. That it occurs on a relatively plane portion of a flat bone makes it even more likely that these are scuff marks and not butchery marks.
I think I can wind it up for now. If anyone wishes to refute the empirical claims that I've made in this post, please feel free. However, I think we can safely forget that this paper was ever published, and get back to contributing to knowledge with well-reasoned inferences from the archaeological record, like good scientists.

Tuesday 20 December 2011

Archaeologists Find Neanderthal Dwelling Made from Mammoth Bones

     Published online this very day. 'Mammoths used as food and building resources by Neanderthals: Zooarchaeological study applied to layer 4, Molodova I (Ukraine).'
     Look at the scale! Look at the paucity of remains in the 'Circular accumulation of mammoth bones! Not enough for a foundation, much less an entire building! What sort of pattern would result when a dead elephant is repeatedly scavenged? Prolly quasi-circular! I can almost see the outline of a pachyderm in the lighter area inside the 'Circular accumulation.' When is it going to stop? When will they learn?
     I'll have more to say in the coming days. I can't wait! [Comment added at 8:17 PST on Dec. 20, 2011: this paper should never have been published. It lacks any useful discussion of the geomorphological context, which to me appears to be clay-dominated and therefore a mire. It's a place where very large mammals would naturally end up if unlucky enough to lumber by. I've pointed out the shortcomings of the 'hut' hypothesis. There's plenty more. But it'll have to wait. Since they cite 50, 60, 70, 80-year-old literature it might take a bit of time to be seriously critical of this work. But the signs aren't good.]

Site plan reproduced from Demay, Péan and Patou-Mathis (Quaternary International 2011, doi:10.1016/j.quaint.2011.11.019).

Monday 19 December 2011

Science Magazine and the AAAS Take Note: Sibudu Cave's Fantastical Insecticidal Palaeo-Mattresses

In my last post I laid out a blueprint for the subversive archaeologist--examine every argument's premises to see if they are well warranted or not. I really don't mean every claim. Practically speaking, the vast majority of archaeological inferences are (relatively) straightforward and require little (if any) scrutiny--'this is a rock; this is a flake,' 'that is ash; this is charcoal,' and so forth. These are (usually) inferential statements of such high probability (backed up by innumerable instances of the same kind), that it's reasonable to treat them as 'facts.'

Sibudu Cave is in shadow in this 2011 topographically exaggerated, artificially oblique-ified view looking northeast, remembering that in the southern hemisphere the sun is in the northern sky (Thanks, Google earth!)

In this post I want to provide a case study of an 'argument from want of evident alternatives,' about which I wrote in the previous post. I'll walk you through the problem I've identified in the recent report from Sibudu Cave, South Africa--where archaeologists claim to have discovered evidence of the oldest purposefully constructed vegetation mattresses in human history. 
[I promise not to mention that many animals collect plant material to make 'nests,' and that it's just the Sibudu archaeologists' speciocentric bias that compels them to treat a human 'nest' as something special. Oops! I guess I just broke my promise. Mea culpa.]
Archaeologist Lyn Wadley and others were excavating in a rockshelter with a Middle Palaeolithic (MSA) component when they came across 15 layers of decomposed and oxidized vegetation. While horizontally quite extensive these layers are thin--about 10 mm--and comprise a number of species that still grow in the area. These laminae of vegetation also include small lithic debitage and broken and burnt bone. One of the layers, about 1000 mm by 2000 mm in plan, comprises leaves of just one species. Wadley contends that, with evidence of a number of different plant species in the other layers, an accumulation of a single species seems unlikely--full stop. The remainder of their claims about the 'bedding' follow from this, and depend on the premise that such an accumulation is 'unlikely.' Insecticidal properties of the single species points to an intention to use it in preference to others to keep the work/sleep area free of pesky critters. The inhabitants regularly burned their old bedding to rid them of vermin. These subsidiary claims are totally undermined if the original premise is shown to be in error, and rendered virtually toothless if natural processes could have been responsible.
     I suppose it goes without saying that the Sibudu Cave excavators have not attempted to rule out natural processes in the production and preservation of these vegetation layers. Instead, they simply assert improbability and leave it at that. I'm not accusing them of disingenuousness. Yet, I find it amazing that they didn't take a moment to consider the possibility of other, expectable, natural causes. All I need to do is propose an alternative natural process and down goes the house of cards.
     Sibudu Cave [rockshelter, really] is a large, low, semi-circular escarpment formed in Ordovician sandstone about 40 km north of Durban, South Africa. It's the head scarp of a small valley that extends southwestward from the cliff face. As can be seen in the Google Earth overview above, the present-day natural vegetation is dense. By all accounts it was similarly dense in the archaeological past. 

Sibudu in sunshine. In this view you get an idea of the hollow formed by the escarpment and the surrounding terrain--in other words, a sediment trap (Click here for photo source).

In the site plan (below) you can see that the cave's aspect is due west, and that the talus slope formed by the weathering bedrock slopes sharply downward as you move from north to south along the 'rockshelter wall.' In such circumstances you can expect local sedimentary input from the weathering bedrock, as well as from the surrounding terrain. And because of the sloping rockshelter floor you can anticipate a relatively constant downslope movement of surface sediments due to a number of natural processes, among them short-distance fluvial and colluvial transport.

Sibudu Cave site plan (Villa et al. 2005)

Archaeological sites in such landforms develop in unpredictable ways. At times they can be net depositional, at others, they can be net erosional. They are very prone to flushing out by running water, which creates temporal breaks of unpredictable magnitude, and they are easily and predictably susceptible to what's called 'reverse stratigraphy,' where objects that find their way into low-lying areas can be buried by older sediments transported from upslope. 

In this view it's possible to see the steepness of the north-south slope (If you took this photo or know its ascription, please advise how I should best handle the credit).

Villa et al. (2005) publish a profile of the excavation's north-wall (shown below), which illustrates nearly horizontal layers in the west-to-east direction at the surface. By presenting the site stratification using this profile the authors are [one hopes] inadvertently downplaying the potential for re-entrainment and secondary deposition across the excavation area. 

Excavation profile illustrating the north wall of squares B5 and B6 (Villa et al. 2005). 
To illustrate the potential for downslope transport in the excavated area, I developed a generalized slope diagram from the site plan, seen below, which allows you to see the north-to-south slope perpendicular to the plane of the profile drawing. The slope is fairly steep, and it wouldn't take much surface water or treadage to mobilize small particles on the surface. A downpour would no doubt create a torrent on a slope of this magnitude, capable of transporting sediments up to and probably exceeding small pebbles.

Schematic north-south slope of site sediments based on contours in the site plan above, showing the location of the profile in the excavation profile reproduced below.

 You can also see in the excavation profile that most of the sub-surface layers dip gently toward the bedrock. Regardless of the reason for this west-to-east, downward trend, the resulting low-lying areas would tend to act as sediment traps. This means that, in addition to sediments transported from upslope to the north, those sediments from west of the cave wall would, when mobilized, tend to fill in the lower places, nearer the wall, with older sediments. All in all this is not an archaeological site that lends itself to inferences that depend on fine chronological control, or horizontal spatial integrity for that matter. By contrast, these depositional circumstances mean that it's no surprise that blankets of leaves collected and were preserved at times in this place, because of the more-rapid burial expectable in the lower lying areas near to the wall.
     The excavators claim that the strata of preserved vegetation are the result of deliberate preparation of a comfortable working/sleeping surface. Moreover, they claim that the bed builders regularly burned old vegetation mats, and that in one case they selectively collected the leaves of one species because it conferred an insecticidal property to the area of the leaf mat. In support of these claims the authors employ just a single premise. And it all boils down to this statement: 
'Many woody plants grew near Sibudu during the MSA; thus, single-taxon windborne leaf litter seems improbable.' 
As far as I can tell this is the only reason they concluded that purposeful human/hominid behaviour is the explanation for such a deposit. But, why must we accept that only wind-borne leaves could have contributed to the deposits?  
     I'm mystified as to their reasoning with regard to the source of the vegetation mats. Given the likelihood that, in the MSA, dense vegetation grew everywhere in front of and above the cave (indeed, all but in the drier areas underneath the overhang, much as in the present day photo, above), let's imagine instead a more likely scenario--leaf-fall. A plant grows, loses leaves, and those leaves come to rest beneath or very near to the stalk or trunk. It's the origin of the term leaf litter. Makes sense, doesn't it? We don't need to construct an elaborate scenario whereby the palaeo-humans went about collecting leaves for bedding--they merely had to use what nature would in all likelihood have provided for them. Or, am I missing something?
     And what about the single species mat? No real mystery there. The species in question is Cryptocarya woodii. This is no bush, nor is it a shrub. It's a hulking great tree! Moreover, it's not a mostly leafless, splindly thing like the one in the photo above. It's a tree that can grow to 20 m high, and from the look of the growth habit visible in the photo below, the tree is every bit as wide as it is high, and has an abundance of leaves. Hmmm.

Cryptocarya woodii grows from 5 to 10 m high, but it can grow to 20 m in favourable conditions (Photo credit).

Given the species in question, how unlikely is it [really] to imagine a 1 m by 2 m 'carpet' of leaves accumulating beneath a single individual of the species that would have dominated a 20-m diameter area? Not very, unless I miss my guess. And what about the mat remaining intact while natural processes buried it? Well, in a closed woodland, at the end of a valley, you might not expect too much in the way of air movement that could blow the leaves around once they'd fallen to the ground. Clearly the right circumstances prevailed to have aided preservation, unless we imagine purposeful burial of disused mattresses! What about the follow-on assertion that the vegetation mat was insecticidal? You tell me! Almost all plants produce substances that are toxic to other organisms. Think about it. Deadly nightshade. Oleander. Wormwood. Hemlock. I could go on. Cryptocarya woodii  happens to produce a substance that mosquitos avoid. Whoop-de-do. Given the improbability that the palaeo-humans made this bed of leaves, how likely is it that they chose the Cryptocarya woodii blanket over other accumulations at Sibudu so there wouldn't be clouds of mosquitos buzzing around? I'll leave that up to you to decide.
     I've hope I've said enough about Sibudu Cave to persuade even an antagonistic reader that there are major problems with this article. So, I'm done with Sibudu. 
However, I wouldn't consider my job complete under the circumstances without a word or two to the scholarly society that published Wadley et al.'s 'Middle Stone Age Bedding Construction and Settlement Patterns at Sibudu, South Africa.' Responsibility in this case lies with no-less-august a community than the American Association for the Advancement of Science, publisher of Science, one of the most read journals in the universe. How in the world did Science find such credulous editors and reviewers? You don't have to be an archaeo-botanist or Sir Isaac Newton to know that leaves fall and come to rest underneath trees! A three-year-old knows that! 
     And it's one thing for the media to hang on every fantastic narrative that gets published, but it's another thing entirely for a peerless, peer-reviewed, journal like Science to accept for publication a set of claims based on such an implausible premise and nothing else. Furthermore, even if it were a plausible premise, which it's not, since when does Science publish research that's based on plausibility arguments? Does Science have some sort of social-science quota that they need to satisfy to placate their readers? Are they so hard-up for good original contributions from archaeology that they would lower themselves to publish it? I doubt it. Hey, maybe they have a hidden agenda aimed at portraying the social sciences in a bad light by publishing poorly reasoned submissions! 
     More than likely the scientists who refereed the paper were too enthralled by the cool micromorphological thin sections, and the scanning electron micrographs, and the other science-y stuff included in the Science article to be critical of the argument. Sad. I'm done.

Next up: Qesem Cave and the extirpation of Homo erectus in the Levant: an article entitled 'Man the Fat Hunter.' Another clunker from PLoS ONE
[I think the authors of 'Man the Fat Hunter' should have used a hyphen in the title, unless they wanted to imply that Homo erectus, as a species, was fat! Something tells me that's not the case.] 
[If you find me remiss in not quibbling with the gender-exclusive language in the title, please understand that those of us old enough to remember Sputnik know that the title is an allusion to a pivotal conference in palaeoanthropology--'Man the Hunter'--which took place in the 1960s, and set the terms for the archaeology of human evolution for a generation thereafter.] This is gonna be so. Much. Fun.

Saturday 17 December 2011

Questioning Sibudu Cave's Palaeo-Bedding and Qesem Cave's Dual-Species Extirpation. Part One: The Epistemic Background

One of the reasons I write this stuff is to encourage other archaeologists to exercise their critical 'franchise' by examining the premises of archaeological arguments. You can do it, too! And all you need is a little help from The Subversive Archaeologist. But first you need remember the SA 'mantra'.
     I received my 'archaeological mantra' from Knut Fladmark (Professor Emeritus, Simon Fraser University). It is this: 
When you encounter novel or unusual archaeological deposits (even if they resemble circumstances with which you may be familiar), you must make every effort to rule out natural processes before (tentatively) claiming that your observations are the result of human or hominid agency. 
I received the corollary of my 'archaeological mantra' from Diane Gifford-Gonzalez (Professor, University of California at Santa Cruz). It is this:
When attempting to rule out natural causes for novel or unusual archaeological deposits, you must make every effort to include as broad a range of well-understood processes as possible before (tentatively) claiming to have identified the process or processes that can explain your observations. 
Sounds easy. Evidently it's not.

[Aside: I often use the phrase 'knowledge claim(s).' It's just a convenient way of encapsulating a very broad range of statements that one can make about just about anything, from the mundane to the divine. 'It's nine o'clock in the morning' is a knowledge claim. With very few exceptions, every knowledge claim is an argument, based on observations of some kind that are interpreted using inductive reasoning. As a result claims such as 'This is a bifacial thinning flake' or 'this is palaeo-people-poop' are not  statements of immutable fact, but rather they are statements that are either closer to or further away from an accurate rendering of reality. As Diane Gifford-Gonzalez underscores in a recent Touchstone Thursday article, no matter how authoritative you sound or how strenuously you make your claim you can't get it right if your premises are unwarranted or just wrong. And that is the foundational principle of The Subversive Archaeologist.]

Being a subversive archaeologist begins with the ability to identify fallacious arguments. For example, it's just not good enough to say that such-and-such a circumstance seems (or is) unlikely. Statements about the likelihood of this or that occurring must be accompanied by a well-warranted justification, or you leave yourself open to accusations of charlatanism (i.e. being a 'snake-oil merchant'), because swindlers often use similar assertions to persuade their victims. In informal logic terms, this is a species of fallacious statement known as 'argument from want of evident alternatives'. I don't wish to accuse archaeologists of being charlatans or engaging in a con game. In fact, I believe strongly that very often archaeologists 'con' themselves into accepting their own arguments from want of evident alternatives, either because they really want their claims to be true, or because they truly see no evident alternatives. Neither is sufficient to support an argument for which there are alternative explanations. [Pointing out when archaeologists are making this mistake has, it turns out, been the main contribution of my career.]
     What does it take to become a specialist in picking up on unwarranted or erroneous premises of archaeological knowledge claims? The short answer is that it depends on having a lot of background knowledge drawn from numerous independent domains of enquiry, be they anthropological, ethnoarchaeological, geological, zoological, botanical, cosmic or other. The more, the merrier, in fact. As you will see in what follows, a very little useful knowledge from outside the excavation square can either support or dismantle any interpretation based solely on what's encountered in the spits.

In this series of three posts I want to use two recently published archaeological reports--both widely acclaimed in the media--to illustrate how easy it is for archaeologists to deceive themselves and how readily the media gobble it up like manna. One of my examples comes from Sibudu Cave, in southern Africa, and regards a claim for the earliest bedding in the archaeological record [They're serious!]. Moreover they claim to have evidence for the earliest insecticidal [!] bedding material in human history. [Afterthought posted at 17:39 PST, December 17, 2011. Geez, if they could figger out how to make insecticidal bedding 77 kyr ago, you'd think we'd have whipped the bed-bug problem by now. More reason for skepticism about their claim!] 
     The other example is another problematic claim from the excavations at Qesem Cave in Israel [I'm not singling them out for abuse. I can't help it if they keep making ampliative* inferences that just won't stand up to scrutiny, and the media keep running with it!]. This time the Qesem excavators claim to know the reason for the simultaneous extirpation of elephants and Homo erectus in southwestern Asia between about 200 and 400 kya. It seems that H. erectus depended on elephant fat for its survival, and when the elephants went away, so did H. erectus.
     Please understand that I'm not quibbling with the idea of bedding, or even the first bedding, or even the first insecticidal bedding. I've seen the traces of bedding in southern central British Columbia's archaeological housepits. I know that such traces can be preserved intact. It's entirely possible that the archaeological record contains traces of the earliest bedding. However, one must be careful in making such claims, and the Sibudu Cave archaeologists haven't done their homework. Likewise, something must have occurred to spell the doom of elephants and Homo erectus in southwestern Asia (if indeed it was simultaneous--it's never an easy claim to support). But the Qesem Cave archaeologists haven't adequately justified their assertions. And I feel it necessary to point out where they have it wrong.
     More to come.

* A term you now recognize because like good little neophyte subversive archaeologists you've by now either re-read or read for the first time the Gifford-Gonzalez article that I extolled in the latest Touchstone Thursday post.