Sunday, 30 October 2011

Mwahahaha...You're Going to Watch This Grow Into a Fully Fledged Refereed Article


All the Better to Track You With, My Dear
by Robert H. Gargett
Hominin morphology says nothing on its own about its adaptive underpinning. Instead, we human palaeontologists must interpret evolutionary significance as best we can. The Neanderthal face is an enduring example of the difficulty that confronts us when trying to infer the selective advantage that gave rise to a structure or a set of related structures. 


Forbes Quarry Homo neanderthalensis and a recent Homo sapiens (illustration from Rae, et al 2011)
Much to the frustration of palaeoanthropologists, when looking for reasons for morphological change, we are limited to just those possibilities that are imaginable in our worldview, and not, necessarily, what is possible in biological reality.

In the spirit of widening the range of possibilities for the selective pressures that gave rise to the Neanderthal face, in this paper I use as a jumping-off point the isotopic analyses of Bocherens and his colleagues (e.g. 1999). Bocherens has shown us that the Neanderthal's bone chemistry is almost identical with that of carnivores and not at all like that of herbivores or other great apes. Using that knowledge as a springboard, I argue that the face of H. neanderthalensis took on its distinctive morphology in response to a phyletic transition from ominvory to carnivory. Indeed, I propose that the distinctive morphology and size of the Neanderthal nasal aperture, the orbits, the infraorbital foramina, and the infraorbital portion of the maxillae came about in support of a reassertion of the olfactory sense when compared with the trend in Primate evolution and the state of olfaction in the other great apes, extant and extinct. In lay terms, the Neanderthals and their predecessors (or antecessors, as the case may be) were growing an ever-larger snout—to enable them to succeed at a trophic level quite different from that of earlier, contemporary, and later members of Hominina. 


Background
The size and evolutionary significance of the mid-facial region in the Neanderthals has been the subject of scholarly discourse almost from the earliest discoveries a century and a half ago. When viewed in norma frontalis the salient facial features are the orbits and the nasal aperture, which are gargantuan openings when compared to the measly recent-human exponent. In large part I think the eye sockets have been overlooked, but for generations the Neanderthal's nasal aperture has been viewed as an adaptation to the cold air of the periglacial environment. To others it is the result of a rigorous ecological niche and the combination of biomechanical factors imposed by anterior dental loading (suggested by the distinctive wear patterns on Neanderthal incisors, among others). Neither explanation is satisfactory, and never has been. The cold adaptation thesis never had empirical support, as is correctly pointed out in a recent paper by Rae, Koppe, and Stringer (2011). As for the biomechanical hypothesis, there is hardly a bony or chitinous structure in the animal realm that is not present as a result of biomechanical necessity. It's a proximate explanation that begs for an ultimate explanation.

The "Old Man" from La Chapelle-aux-Saints (illustration found on web...if you know the correct attribution, please let me know) 

Household Archaeology, continued (tip of the hat to Emerita Professor Ruth Tringham for the title concept)

I'm into the Pliocene dishes now. Almost to bedrock. Unfortunately the uniformitarian principle let me down earlier today. The new towels 'ran' and turned the white things faintly rouge. Maybe if the colour 'ran' once, it'll run right back out again the next time I wash the whites. Is that what they call wishful thinking?

Saturday, 29 October 2011

Archaeology at Home...

Others may be able to multi-task in such situations. However, SA is  a mere mortal and is having to take a break from illuminating the dark underside of archaeology. I'm the PI on a long-overdue project to investigate the deeply stratified site that comprises the kitchen sink and laundry hamper. From the look of it, I'll need to use shoring, which as you all know will almost certainly prolong the excavation. Be back soon.

Friday, 28 October 2011

Almost Forgot! All the better to eat you with, my Dear...

In my haste to enlighten you regarding the Neanderthal face I completely forgot about the teeth. If you were doing all that you could to remove everything edible from an animal carcass, would you not treat the shaft of a long bone like a cob of corn? And wouldn't that create anterior wear like that exhibited by the Neanderthals?
     Too easy? Why make the solution hard. It fits. Doesn't it?

Thursday, 27 October 2011

Can You Say "Extreme Survey"?

Alas, once again you've caught SA staring at the newsfeed (now in four languages). Those high-school French classes sure come in handy! 


Every once in a while an archaeological project comes along that sets new standards for spatial and temporal integrity. This project is staggering in its scope.

Bottom centre, archaeologists work simultaneously on 30 kyr-old and 50 kyr-old sites, 6 and 7 metres beneath the surface, traces of modern humans and Neanderthals, respectively (Denis Gliksman photo, INRAP).

In the extreme north of France work progresses on a portion of the canal Seine-Nord de l'Europe, an immense excavation project is enabling what must be the largest 3-dimensional archaeological survey in human history. The scale can only be fathomed pictorially, and INRAP (l'Institut National de Recherches Archéologiques Préventives) has kindly provided us with an up-to-the-minute birds-eye view of the undertaking, complete with rare glimpses of Late-Middle and Early Upper Palaeolithic archaeology that are truly boggling—extensive archaeological sites on the order of 1,000 to 4,000 sq. m. These are not encampments, but places where paleo-people left their mark, just the same. From yesterday to the Mousterian and everything in between. Flint artifacts and well-preserved animal bone are the predominant traces, and while numerous, the artifact scatters are by no means dense. Yet, they tell a story that would not otherwise have been told: what life was like for Neanderthals and modern humans in periglacial Europe.

Wednesday, 26 October 2011

The Neanderthal Face: All the Better to Smell You With!

Ambitious anthropologists take note: 
I'm in no position to flesh out [cough] the points that I make in this thesis. I'll gladly grant anyone leave to investigate this further as long as the energetic (and fearless) anthropologist who does so is careful to acknowledge from whom they acquired the skeleton of the argument—moi.
The Answer Was Right Under Our Noses All Along...
In all the time I've spent in and around archaeology and palaeoanthropology I've never heard a satisfying explanation for three features of the Neanderthal skull that make them distinct from ours: mid-facial prognathism, an enlarged nasal aperture, and a large infraorbital foramen. I want to suggest that the answer lies in the sense of smell needed to succeed as a carnivore, which arose in the European Homininan lineage, of which the Neanderthals were almost certainly the final expression. These Ice-Age Europeans were in all likelihood growing a snout.


Biological anthropologists have trouble deciding whether or not the large nasal aperture and mid-facial prognathism is the result of anterior dental loading, or something biomechanically and behaviorally independant. For years it was argued that they needed more nasal real estate to warm the cold air that they would have encountered in Ice-Age Europe and western Asia, where they lived. 
     To say the least, the jury is still out on these matters of the Neanderthal face. In this post I want to posit a new explanation, one that I imagine hasn't occurred to any Very Serious Anthropologists because they imagine the Neanderthals to be a lot like us. As you'll see, this has probably blinkered them from recognizing the possibility that Neanderthals had evolved specialized structures for enhancing their sense of smell. In other words, they grew a snout like others in the carnivore guild, because the olfactory sense is of prime importance at that trophic level. 
     As you'll recall, Herve Bocherens and his colleagues have determined isotopically that the Neanderthals were probably obligate carnivores—their stable isotope signature is on a par with the big cats and a far cry from that of, say, cows and horses. My understanding of evolution means that I can't ignore the trophic level occupied by a species in trying to understand its skeletal evolution. What Neanderthals ate and how they acquired their food would have been reflected in their skeleton, no less and no more than that of any other animal species, including our own. 
     It's also likely that the Neanderthal's trophic habits didn't evolve overnight. Given that we think earlier Hominina were seed eaters or omnivores, a shift to carnivory in a homininan lineage would have taken a very long time, perhaps stretching back to the early Pleistocene, at a time when our ancestors emerged from Africa for the first time.
     So, we must hypothesize a long, mosaic evolutionary process from omnivory to carnivory in the Neanderthal lineage. And, from what we know of other species' evolution, such a huge behavioral transformation would have been accompanied by biomechanical and concomitant skeletal changes, which I would argue worked together to produce the distinctive face of Homo neanderthalensis.
     The swing from omnivory to carnivory, it seems to me, would have necessitated a major realignment of the priority of the senses, with the sense of smell asserting itself. Because of this, the soft- and hard-tissue structures supporting the olfactory sense could not help but have changed, too. Change would have been necessary because homininans had inherited a much-reduced olfactory sense compared with their Primate forbears. Remember that one of the major trends in Primate evolution has been the progressive reduction in dependence on the olfactory sense, with concommitant changes in the facial skeleton—including reduced prognathism. The Primate nose took up less and less facial real estate as time passed in the Cenozoic. So, what's a homininan carnivore wannabe with a small nasal aperture and terminally impaired sense of smell to do? Grow a snout!
     Look a little closer at the Neanderthal face and you'll see that the nasal aperture is one of the most prominent structures of the Neanderthal face when viewed in norma frontalis, as in the La Ferrassie specimen shown above. It's significantly larger than that of Homo sapiens. The same is true of the infraorbital foramen, another outsized landmark when compared with that of modern humans. 
     The infraorbital foramen transmits the infraorbital nerve (ION), which only recently has revealed its anatomy to interested facial surgeons Kyung-Seok Hu et al. The ION is a ramified structure that supplies the skin and mucous membranes of the middle portion of the face, including the inside of the nose, and is therefore critical to the sense of smell and therefore of great importance in this discussion of Neanderthal facial skeletal evolution. According to Kyung-Seok Hu et al. the ION has four main branches, of which one, the internal nasal branch, innervates the skin of the philtrum and has a terminal branch that supplies the nasal septum and vestibule. These structures help to support the olfactory sense.
     For those of you who, like me, don't have a clue what the philtrum is, a picture is worth a thousand words. The philtrum is vestigial in humans and higher primates. However it and its related structures are of the utmost importance in most mammals. It is
a medial cleft common to many mammals, extending from the nose to the upper lip, and, together with a glandular rhinarium and slit-like nostrils, is believed to constitute the primitive condition for mammals in general
The Philtrum  (Mikael Häggström photo [Creative Commons])
     I wouldn't suggest that the Neanderthals were re-expressing the rhinarium of the lesser primates. Nonetheless, all of this means that the ION is intimately connected with olfaction. Moreover, in carnivores the ION's size usually tracks that of the overall muzzle size. Dogs, for example, have long snouts and relatively very large IONs, and depend to a high degree on their sense of smell. Same with cats and other meat eaters, but to a lesser degree.
     So, what are we looking at here? Neanderthals exhibit obligate carnivory. They have an oversized nasal aperture, which implies greater surface area inside the nose, along with the potential for enhanced olfactory capacity. A larger infraorbital foramen would have transmitted a larger ION, necessary to support an augmented olfactory sense. The mid face was become overall larger and more prognathic. All of these factors mean that Neanderthals must have had a much better olfactory sense than you or I, and would thus have been more successful as members of the carnivore guild. Nothing says they needed to be top carnivores. They could have done very well as scavengers, or as occasional hunters, like, for example, hyenas.
     Problem solved! Any questions?

Mommy, why is that man always complaining?

It seems that even when I try to make a positive contribution to knowledge I'm doing it in response to something that's amiss in someone else's reasoning (at least to my mind). I once wrote a book about how some animals can create spatial patterning in caves. I intended it as an original contribution to archaeological inference-making. But I undertook the work because I thought that others were reasoning enthymematically in using their understanding of modern human behaviour to guide them in interpreting spatial pattering in pre-modern Homininan archaeological sitesin effect they were arguing that the older material must be the result of modern-like concepts of space held in the minds of the earlier beings, because, after all, moderns leave spatially patterned traces on account of culturally prescribed patterns of behaviour. A rather vicious circle, I thought. 
     I knew that there were all kinds of ways that objects in confined spaces can be moved around unintentionally, which then end up being patterned. It's one of the reasons I've argued for the natural burial of Middle Palaeolithic Homininae. I thought that if I could demonstrate my suspicions about animals and space using the archaeological or fossil record, it'd be useful knowledge. Apparently I was mistaken in my overarching aim. The book, however, was a runaway best-seller on the remainder tables.
     My research, of course, has earned me no lasting friendships. Mostly I imagine it's because no one misses the implications of my work for their work, and, truth be told, my motivation is fairly transparent. But my depauperate social life concerns me far less than the 'chilly climate'* effect that this universal response to criticism has for archaeological practice. I ask you. If we are not free to question the work of others, how can we call archaeology a science? I think we debase the ideals of empirical enquiry when we act as if anyone's inferences are above scrutiny.
     It will be very interesting to see how Sandgathe et al. (whom I mentioned in my very first Subversive Archaeologist post) will get on in the academy after a) presuming to question the inferences of two generations of French archaeologists who worked at Roc de Marsal, and b) getting it right, finally, and (to my way of thinking) showing the archaeological community that there is value in such investigations. 


     I remember hearing somewhere that archaeology has no tradition of criticism such as exists in the humanities and the arts. Perhaps the time is ripe. I hope to live long enough to see a generation of archaeologists for whom being critical isn't deemed anti-social. 


* I want to acknowledge feminist philosophers for this termit's equally apt for the social circumstances of archaeological practice that I'm describing.

Tuesday, 25 October 2011

I won't mince words: This is Shameful

This building might look really good, but perching it atop an Arab cemetery and destroying the burial ground in the process looks really bad...
Proposed Museum of Tolerance, Jerusalem
Moreover, the irony in the name is too palpable for words. This is one of those cases, I think, where despite the realitythat the area has been a parking lot, and the cemetery declared disused by the Muslim descendants of those buried theresuch a high-profile project, funded by the Simon Wiesenthal Center, might have found a less symbolic plot of land on which to site the building. Simon might well be squirming in his grave.
     Three cheers for the 84 international archaeologists who're decrying the project and begging for it to be relocated.

Monday, 24 October 2011

A Corporate-Culture Anthropologist Speaks Out Against Anthropology

This is truly wrong-headed. Anthropologist J. Harper has decided that Florida's governor, Rick Scott (pictured below) is fundamentally correct when he avers that in Florida anthropologists are superfluous and educational expenditures to support their tutelage is a waste. Dr. Harper sees the discipline in the way of a dysfunctional family, and the prospects for gainful employment as less than hope-inspiring. 
     I believe that anthropologist Harper is being ruled by the belief that an education is a means to an end—i.e. a jobalthough she does allow that anthropology is intrinsically valuable as a course of study.  I'm very concerned by her frank assessment, since it means that the university is once more becoming the 'playground' of the elite, and that not only can't the rest of us afford to continue to attend, but also that at the end of the day it's throwing good money after bad, since the jobs aren't there when we come out.
     For all sorts of reasons I have a suspicion that this day and age will be looked back on as a watershed moment in the history of the Middle Class. I see the current situation in education, of which Dr. Harper writes so bluntly, as evidence of a return to a kind of feudalisminvolving the widespread occurrence of indentured servitudeas one after another of today's Middle-Class university students are forced to work for years after their degrees to repay their feudal lords, the banks. 
Governor Scott of Florida

There's a Hole in The Bucket...

There's a hole in a wall in old Pompeii, due to torrential rains in recent days. 
The Italian police are looking into it


Sunday, 23 October 2011

Astronomy is Archaeology or It Is Nothing!

I've worked in conjunction with astronomers and astrophysicists for the past seven years and more. I'm struck by the naiveté among astronomers about the way they make knowledge of the universe. For the most part, they are physicists first and astronomers second. So, they're used to thinking of what they do as a 'hard' science (as opposed to, say, archaeology, which I'm sure they'd say was fairly squishy in the science department). And, although they believe their science to be an exact one, they are always amazed, confused or delighted when their expectations drawn from what they know of physics can't be reconciled with what they've newly observed.
     I wonder if they don't intuitively (a dirty word to most 'hard' scientists) understand the ambiguity inherent in making knowledge of the past. When I talk to them, they seem puzzled when I suggest that their 'data' are presently occurring phenomena, and that everything they think they know is based on well-understood physical phenomena that they can observe only in the present. However, rather like evolutionary biologists, who understand a great deal about what life is all about in the here and now, but who are at a loss to explain how life began, astronomers are, if not at a loss, taxed to the limit when it comes to understanding the early days of the universe with only present knowledge to guide them. 
     The similarities don't end there. I find in astronomy the same dichotomy of aims that I and others have seen in archaeology, and which Kent Flannery so famously and humorously depicted in the Golden Marshalltown. In astronomy there are 'observers' and 'cosmologists' just as in archaeology there are the 'Old Timers' who collect data and the theorists who profit from it. Neither can live without the other, yet both have little but disdain for the other's predeliction.
     The truly galling reality for me is that, for two disciplines that make knowledge of the past in identical ways, the disparity in funding is obscene. And that, my archaeological friends, is where the rubber hits the road for me. In truth, the findings of early universe physicists and the findings of archaeologists are equally tenuous, and, at the end of the day equally unlikely to change the life circumstances of a single human being, but only the archaeologists seem capable of seeing it that way (and more than a few are, I think rightly, convinced that they can indeed alter the lives of oppressed people and cultures in danger of assimilation or passive genocide).
    I'll rest for the moment. But I fear that I'll be forced to revisit this curious disparity between archaeology and astronomy at some point in the future. (Was that an oxymoron?)

Saturday, 22 October 2011

Minor Update: 14 kyr Old Mastodon Rib

Wow! I'm gonna go out on a limb and say that Gary Haynes might have a thought or two about yesterday's news in Science, the publication of the American Association for the Advancement of Science, which trumpets [ouch] the claim that a tiny sliver of mastodon bone imbedded in another mastodon's rib head was the work of human hunters. I don't dispute the fact that humans were in the Americas that long ago. I don't dispute the likelihood that they hunted these beasts. However, the authors have failed to rule out natural causes and that leaves me skeptical. Here is one of the official images from the Science article. Look at the scale. It's an impressively small fragment of bone. More on this in a later post. I'm hoping Gary'll chime in. Better him than me, simply because he's the one that literally wrote the book about present-day elephant behaviour and how it informs us about the fossil record. 

Gin and Tonics All 'round, Then?

Friday. End of the week for those of us in the Western Hemisphere. A squeeze of lime to anyone who can tell me where the title quote comes from. Shhhhh. Here's a hint.

Testing, One, Two, Three

This is a test of the new mobile version of SA. Someone please leave a comment if you think it's easier to view than previous posts using the same template as you see on your PC.
Thank you.
The Management

Friday, 21 October 2011

Xiaoze Xie: Resistant Archeology

This is happening a few hundred metres away from my office. Even if you can't make it to the exhibition, you ought still to know that this artist thinks archaeology is a profound enterprise.
Detail from April–December 2008, G.Z.R.B. (Guangzhou Ri Bao), 2011
Xiaoze Xie: Resistant Archeology
Curated by Shelby Graham and Joyce Brodsky
October 12 – November 23, 2011

Xiaoze Xie was born in China in 1966 at the start of the Cultural Revolution and is currently the Paul L. and Phyllis Wattis Professor in Art at Stanford University.

This stunning exhibition of new larger-than-life paintings, prints and provocative video installation, showcases Xiaoze Xie’s use of books and newspapers to symbolize the fragile nature of compressed history and memory. His works are in the collections of the Museum of Fine Arts, Houston, the Scottsdale Museum of Contemporary Art, several distinguished private collections and are currently featured in a traveling exhibition from Bucknell University "Xiaoze Xie: Amplified Moments (1993–2008)."
Detail from Transience, 2011
Closed Nov. 11 for Veteran’s Day  
Gallery hours:
Tuesday–Saturday, 12–5 p.m.
Wednesday 128 p.m.
831-459-3606

"Alas!! Poor Aurochs. I Knew Him Well."

Whoever it was that said archaeologists had fantastic imaginations should probably get the Nobel Prize for Character Judgement! SA was, sad to say, once again mindlessly reading the news ticker, and found this...
     Apparently, somewhere near Stonehenge, archaeologist David Jacques of England's Open University unearthed these little beauties. 800 B.C.E. The archaeologist has interpreted them as ducks. I think they look more like doll-house versions of milk jugs. Who's right? David Jacques, of course, because he found 'em. Them as finds 'em names 'em in archaeology, and the rest of us have to live with the consequences. Even if they're not milk jugs, nothing about these carvings shouts "Duck!" either. Or am I missing something. Move over Berekhat Ram!
     What do you think these look like? SA wants to know.
Aren't they just ducky?
And in the "Deer Caught in the Headlights" department, this beauty of David Jacques accompanies the milk jug duck carving article. Sorry, David. SA couldn't resist a comment... You all know how SA would caption this. Give it a try! 15 minutes of fame go to the best caption suggested by a bone [cough] fide SA reader.
Caption Candidate #2: This Ax is a funny shape. Cowabunga!
Caption Candidate #1: Mmmm! Tastes like chicken!
SA's Caption: Alas! poor Yorick. I knew him, Horatio; a fellow of infinite jest, of most excellent fancy; he hath borne me on his back a thousand times; and now, how abhorred in my imagination it is! my gorge rises at it. Here hung those lips that I have kissed I know not how oft. Where be your gibes now? your gambols? your songs? your flashes of merriment, that were wont to set the table on a roar? Not one now, to mock your own grinning? quite chap-fallen? Now get you to my lady's chamber, and tell her, let her paint an inch thick, to this favour she must come; make her laugh at that. (Hamlet V:i)

SA Helps You Keep Up With Anthropology and Archaeology Media News

Don't forget the media news ticker that greets you when you visit The Subversive Archaeologist. If it's happening in anthropology or archaeology it's simultaneously posted here. Now I have no excuse to say "I must have missed that." From Xinhua to the Chicago Tribune. Radio and TV, too. 

How Many More?

What do you think? If a poll were taken today, how many more people, compared with this time last week, know what anthropology is? I hope it's not just wishful thinking. Maybe Rick Scott's done us a favour, and we'll see a fluorescence of interest in what we do and how we think. It would serve him right! Wouldn't it? It might even be ... ironic.

Thursday, 20 October 2011

There Are No Human Races: Final Part of The Evolutionary Biology of Race

I’d like to wind up this series on the evolutionary biology of 'race' by summarizing a few points.
First, there are no races in the biological sense in humansHomo sapiens is a widely distributed, polytypic species, exhibiting considerable genetic diversity within and between the historically defined 'races'.
Second, only a very few heritable traits have been used to construct the racial categories that most of us grow up with.
Third, it's virtually impossible to come up with a racial classification that bears any relation to reality—as soon as one begins to take account of more than a few relatively unimportant traits, the whole idea of racial classification falls flat on its face.
Fourth, unless one is prepared to argue that each and every one of us is a distinct race, the notion of human races has no basis in biology.
As such, we must conclude that the notion of human races is grounded not in biology, but in the bigotry inherent in the racial worldview—'races' are part of a masking ideology that perpetuates the social and economic dominance of the ruling strata of society.

All people ought to be given the respect they deserve as members of the unitary human species, and never judged according to the colour of their skin or the culture of their kin.

What's It Got in Its Genes Pocketses?

I'm already in danger of overworking this rhetorical refrain, but, is it just me? Neanderthal genome got sequenced. Great! Not long, really, after the first gene map of us. So, evolutionary biologists of the world, if I sequence the Neanderthal genome and it shares a novel nucleotide sequence with modern humans, what's the first thing that comes to your mind? NO! It's not that the Neanderthals must have bred with humans. And it's not that they didn't. It's just that on the evidence the only thing we can say is that, in all likelihood, the common ancestor of Neanderthals and modern humans carried the same novel sequence. It's possible that we got it from the Neanderthals, and the genetic evidence could be seen to support that hypothesis. However, an untestable hypothesis it will remain. To say otherwise is to be, at best, mistaken, and at worst, disingenuous.

Wednesday, 19 October 2011

Archaeological Aphorism #1

To say that the Middle Palaeolithic inhabitants of Qesem Cave were engaged in 'systematic blade production' is akin to calling a kid playing with Lincoln Logs (or TinkerToys or Meccano) an architect.

I Know This Isn't Fair. Time for a Reality Check.

I owe a big thanks to archaeologist Anja Roth Niemi, Department of Archaeology and Social Anthropology, University of Tromsö, whom I've never met, but on whose web page I found these lovely illustrations of 8,000 year old blade cores and blades from Norway (after less than a minute searching Google Images). 
     I know it's not really fair to compare these objects made by people like you and me with finds such as those from Qesem Cave (see previous post). But since this is at heart a discipline that relies on comparison and analogy for its inferences, I thought the SA readers deserved to see what real blade technology looks like.



In the arrangement above, have a look at the plan view of the deliberately and beautifully prepared platforms that are used to remove blade after blade with unmistakably blade-like proportions and characteristics (unlike those from Qesem Cave). These cores are designed to be used all around the circumference. Look at the flake scars--repetitive, parallel-sided, top-to-bottom in a single stroke. Moreover, not a sign of cortex. This is what 'systematic blade production' really looks like! And these are (almost certainly) NOT just the best specimens, chosen to showcase what the archaeologist thinks demonstrates the makers' maximal skill. (Click on the picture below to enlarge.)


Like I said already. This isn't fair to Shimelmitz, Barkai and Gopher. But it is does have the advantage of being real.

"I am not *sschlick* a Flint-knapper... I'm *sschlick* an archaeologist!

At the outset, I must confess that I'm not a flint-knapper. I know! I know! Then I shouldn't try to comment on a lithic analysis. But wait! I don't intend to tread on the toes of those whose métier it is to break rocks into smaller pieces. Rather, this is intended as an intellectual exercise--one that applies to the way in which archaeologists classify things in the first place (i.e. typology), the way those types can become reified categories (the 'finished artifact fallacy'), and the whole question of pre-modern human cognition versus that of us, the most recent Hominina. (By the way, for what it's worth, some of my best friends are flint-knappers.)
     Before I can begin to lay out my reasons for being suspicious of claims for 'true' blade manufacturing in the Middle Palaeolithic, there is some necessary background to be given. Blade is the term given to 
... flakes that are at least twice as long as they are wide and that have parallel or subparallel sides and at least two ridges on the dorsal (outer) side. Additionally, a tool must be part of an intentional blade industry in order to properly be considered a blade; tools which show the characteristics of blades through variation but are not intentionally produced with those characteristics are not considered true blades.
Thus, the term blade also connotes modern human behaviour, and as such to have discovered an intentional blade industry as far back as 200 to 300 kya would indeed be extraordinary. And that's why I'm immediately sceptical about the claims made yesterday in "Systematic blade production at late Lower Paleolithic (400–200 kyr) Qesem Cave, Israel," by Shimelmitz, Barkai, and Gopher.  Their argument, in brief, is that the predominant flake type in Qesem Cave is of the long, narrow type, which they choose to see as blades, and thus indicative of modern human abilities.
     Here's how the story goes. At some time in the Middle Palaeolithic Hominina began deliberately preparing largish lumps of rock by removing numerous flakes in just the right places with the aim of producing a final flake of a predetermined shape. This technique bears the name Levallois. Usually the final flake is referred to as a generic 'Levallois flake,' a Levallois 'point,' or a Levallois 'blade,' because archaeologists recognize these shapes as shapes that Hominina have used for about the past 40 to 50 kyr.  
     The following animation demonstrates an idealized version of the Levallois technique. Just click on the pic and press escape to get back to my elegant prose.
José-Manuel Benito Álvarez
The problem with such idealized illustrations is that they tend to blur, if not obscure, the true nature of variability 'in the wild.' In addition to the flakes, François Bordes, whose work defined the Middle Palaeolithic for decades, recognized 14 (!) different 'types' of Levallois cores--which is what's left after the desired flake is removed--each based on what he decided were mutually exclusive and distinctive flake products. Of the 14 only a few are generally employed by archaeologists as descriptive categories: the 'flake,' the 'point,' and the 'blade' tend to be the focus of attention. 
     My friends, Iain Davidson and Bill Noble have previously attempted to convince the lithic analysts of the world that there may be something wrong with the way they're looking at the Levallois technique. First of all, they argue, there's no good reason to think that the core or the flake were the desired end product. They call this the 'finished artifact fallacy.' They might well have called it the finished artifact fantasy! So, since they didn't, I will.
     The finished artifact fantasy presumes that because similarly worked pieces of stone come to rest in archaeological sites this must be evidence that they were an important, if not the most important part of the process. Try claiming the same for the discarded pop top from an aluminum beer can! The plausible reason for the broad similarities among the so-called Levallois cores, say Davidson and Noble, is that they represent a failed attempt to rejuvenate the core. If they'd succeeded, as they must have done often enough to make it a part of their repertoire for at least a quarter of a million years, there'd be nothing left to resemble the Levallois core that we do find here and there. 
     A similar theoretical stance underpins the work of Harold Dibble, who showed us that Bordes's 50+ Middle Palaeolithic artifact types are merely arbitrary points along a continuum of lithic reduction. This leaves the MP with a core and flake technology which, but for the addition of retouch, began at least two million years earlier.
     Of course, if one persists in believing that the final flake was the object from the start, the Levallois core becomes de facto evidence of what the French refer to as très pensées, the thoroughly-thought-out sequence of numerous flake removals that is undertaken to achieve the pinnacle of Middle Palaeolithic flint-knapping--the Flake. And, if you're sensible, and realize that the Levallois 'technique' is nothing more than a flake-tool-oriented continuous reduction process... Well, you get where I'm going with this. Aside from its being a senseless waste of precious raw material, there's nothing admirable or artful about the flakes we see when we are shown more than the 'typical' examples usually portrayed in publications. 
     Before I get to the Qesem Cave claims, I need to prime you by showing you how specious is the claim that Levallois cores are in any way typeable. But you don't have to simply take my word for it! Believe your own eyes. In the following I use numerous examples of the Levallois cores excavated from Douara Cave in Syria. I've collected like-named specimens from a variety of the published figures showing examples of cores, with the aim of showing you the variability WITHIN something called a 'type' of Levallois core.
     

Tuesday, 18 October 2011

Come, Watson, come! The game is afoot. Not a word! Into your clothes and come!

Who am I to question the best minds of the chronometric dating community? I guess we might find out the answer to what would otherwise be just a rhetoricalad hominem response to my intuitive grasp of the issues surrounding the dating of Blombos Cave. Not one, but two honest-to-goodness Physicists have come forward to help yours truly with his 100 kyr old math problem (Fermat's got nothin' on me!): Watch this space. And I'll tackle the lately resurrected claim of blade production in the Middle Palaeolithic of Europe.

Way too much laundry!

Sad to say my evening's been taken up with cooking, straightening my head, and laundry. So much for the promise of revelatory archaeological insight.

Monday, 17 October 2011

Here We Go Again!

It's lunchtime and I'm transfixed, watching the newsfeed going through today's round of essential archaeology news. Then this pops up... Archaeologists find blade production earlier than originally thought
Click to go to the Journal of Human Evolution site to download
Coming, as it were, hot on the heels of the report of 100 kyr old artist's studio at Blombos Cave, indications for modern human style blade production at Qesem Cave some 200 to 400 kya was another kick in the pants. 
     Where do I begin? Well, I'll begin by saying that lunch is now over and I'll return to fill you up with more cogent criticism later today.
     SA, over and out.

Marooned!

They say networking is close to not working. In my case it's not working at all! Where is my rescuer? Where are all the savvy archaeologists when you need them? Or physicists for that matter. My earlier request for help was serious.  I'm lost in the land of OSL special pleading, mathematics style. 
     This is no joke. It's only my intuition mind you, but I'm just a little curious about a chronometric age determination that requires 23 separate equations to arrive at an estimate of equivalent dose. Let's face it: TL and OSL rely on the easiest equation of them all! When did 'equivalent dose divided by annual dose = years in the ground' become so hard?
     Go ahead. I dare you! Read this snippet from page 359 of Galbraith et al. that includes equations 22 and 23. Doesn't it strike you as troubling? Maybe just a bit?

A physicist! A physicist! My kingdom...well, ok my rented studio for a Physicist!

     Thank you, and good night, and good luck to us all.

Sunday, 16 October 2011

Calling All Physicists: This Means You, Rhys Davies!

Be gentle with SA. This post contains an embarrassing confession of (one of) my intellectual shortcomings.

     Alas and alack! My dinosaur-sized brain is hopelessly incapable of understanding the labyrinth of mathematical and statistical calculations contained in this (what I must believe is a) foundation argument for dealing with the (very real) likelihood that sediments samples used for OSL dating

1) may not be of uniform age, or
2) may not have been uniformly 'bleached' (and trapped electrons thereby effectively 'zeroed') by solar radiation or heat prior to burial. 

The article:

R.F. GALBRAITH, R.G. ROBERTS, G.M. LASLETT, H. YOSHIDA, J.M. OLLEY. 
"OPTICAL DATING OF SINGLE AND MULTIPLE GRAINS OF QUARTZ FROM JINMIUM ROCK SHELTER, NORTHERN AUSTRALIA: PART I, EXPERIMENTAL DESIGN AND STATISTICAL MODELS."
Archaeometry 41, 339–364, 1999. 

I know that the scientists who wrote this were sincere, and were trying seriously to overcome some pesky obstacles with which they'd been confronted.  
     Nevertheless, I believe that in their endeavour (and that of those that rely on it for their OSL age determinations) lies the soft theoretical underbelly of all claims for the temporally anomalous antiquity of modern human behaviour at Blombas Cave (if not for others of their ilk).
     So, I'm asking any of you who are, or who know a physicist, mathematician, or statistician, to please come to the rescue of this hapless archaeologist, and the discipline of archaeology, which from my perspective, is and always has been more or less at the mercy of numerical wizardry.
     What we really need is a plain English account of what's going on. Thank you.

Saturday, 15 October 2011

Chi-Squared over t times r = Yes?

The People have spoken...well, fifteen of them. 15/15 is good enough for me! Thanks everyone. Poll coming down.

Friday, 14 October 2011

Just a Tickle...

Thanks to the baker's dozen who've already responded. This is just a reminder to the rest of you that I'm canvassing the vast readership of SA as to whether or not I should continue posting posting notifications to facebook. 

100 kyr Old "Tool Kits?" Terminus Post Quem vs. The Law of Averages

Introductory Archaeology Exam Question...

     Archaeological consultant Professor E. Steemed has been asked to date a cache of Roman coins in Jerusalem. In the cache is an example of every coin ever minted by the Roman Empire. There are no dates on the coins. Instead, they bear the face of the Roman ruler during whose reign the coin was minted. The coins span the time from about 300 B.C.E. to about 300 C.E. What date did E. Steemed arrive at? Pick the best answer.

A) around 1 C.E.
B) no later than 300 B.C.E.
C) no earlier than 300 C.E.
D) none of the above.

Easy peasy! Right? Wrong!
Prof Steemed averaged the mid-points of each ruler's reign and arrived at about 1 C.E. Lost? Me, too. I was similarly lost when I took a look at the background information regarding the Optically Stimulated Luminescence* dates from Blombos Cave, South Africa, published yesterday in Science. Henshilwood et al. have discovered more evidence of modern human behaviour, after previously reporting on shell beads and decorated ochre. This time they have evidence of ochre processing, and two virtually identical 'toolkits' comprising Haliotis shell and traces of dessicated paste or liquid pigment.
Henshilwood et al.
This discovery wouldn't even have made the South African Journal of Science if not for the claim that these items are 100,000 years old--at least 50,000 years older than the oldest securely dated evidence of this kind from elsewhere in the world!
     And how do they know this? 
     As you might imagine, the Subversive Archaeologist is highly sceptical of claims for the antiquity of modern behaviour that stands out as a temporal anomaly. South Africa seems to be a Bermuda Triangle of temporal anomalies. Modern human skeletal material from Klasies River Mouth is claimed to be about 100 kyr old, along with the modern-looking Howiesons Poort lithic industry that accompanied the remains. And, as I said before, previous claims from Blombos are along the same lines. But until now I haven't bothered to look further into the claims. This seems like as good a time as any.
     I had a look at the Supplementary Online Material that goes along with yesterday's Science article. In it Henshilwood et al. illuminate the reasoning behind the OSL age determinations. I think you'll have to agree that the data presentation and interpretation are, at best, intriguing, and at worst inscrutable.


So, what do we have here? It looks very sophisticated, and in the classical sense, it really resembles sophistry.
Henshilwood et al.
     The above diagram is a tri-axial plot of the data derived from a sample of sand grains taken from the vicinity of the Haliotis shells. The X axis is a standardized estimate of the statistical error of the actual luminescence measurement of this sample, which comprises a large number of single grains of quartz sand assayed individually. The Y axis is another estimate of error, and its inverse, which is taken to be an estimate of the precision of each datum in the sample. Each dot represents a single grain of sand that was subjected to the luminescence measurement process. The curved scale at the right is the total dose of radiation that is estimated to have been responsible for the degree of luminscence measured for each grain--the greater the luminescence, the older the sand grain is. Note that the scale is in Grays, a measure of absorbed radiation, and that it's not a uniform scale--the intervals of the upper estimates are much smaller than those toward the opposite end. The actual calendar year age estimates are derived by dividing the estimated total dose by the annual dose rate, itself an estimate of the amount of radiation that a sand grain is exposed to during the course of a year for the duration of its time in the deposit, which has been measured using a portable gamma-ray spectrometer. 
     Estimates piled upon estimates multiplied by error margins. Even though the diagram above is just a representation of the mathematics involved in an OSL age determination, it gives an impression of the potential for error inherent in calculating an OSL age in calendar years. 
     Now that I've opened this can of worms, I won't be able to rest until I'm able definitively to critique the claims from Blombas Cave. This means I'll have to read and digest all of the literature referred to in Henshliwood et al., until I'm sure that I understand all of their reasoning, statistical and otherwise. Dang, this is going to be worse than Statistics in Archaeology with Jack Nance!
TTFN.


* developed at my alma mater, Simon Fraser University!

100,000 kyr Old Pigment/Ochre Tool Kits! As if.

I'll have something to say about this. So, watch this space...

Archaeologists find 100 000-year-old ‘toolkits’ near Cape Town

Thursday, 13 October 2011

Tongue roll, please...: Part Four of The Evolutionary Biology of Race

In my last post on the evolutionary biology of 'race' I spent considerable time on skin colour and its variability. I hope it's obvious that I chose skin colour to begin this part of the discussion because of its long history of use as a 'racial' determinant. I'm also hoping I was thorough enough to have persuaded you that, at least as far as skin colour goes, 'racial' categories are specious.
     There's a very large number of heritable traits, like skin colour, that are the product of more than one gene, resulting in continuously variable characteristics. Height is a good example. Look deeper and you see that there's no single superficial trait, such as hair type, skin colour, nose shape, stature, ear shapeyou name itthat distinguishes one so-called race from another. Moreover, looking at the superficial qualities of people’s skin, hair, and noses ignores the very large numbers of other genetically determined traits that you can’t see, or may not be aware of even if you can see them. 
     Here are a few examples. How many of you can roll your tongue lengthwise in your mouth? You might be surprised, as I was, to learn that some people can't. The ability to roll the tongue is genetically determined, and variable across the human species, within and between the traditional 'racial' categories. 
     Did you also know that there are two types of ear wax? About 98 percent of northern Chinese have dry ear wax, while about 84 percent of pale-skinned Americans have a waxy substance in their ears? My partner from the United States didn’t even know that the waxy stuff existed, because her entire family has dry ear wax. It's a recessive gene variant, and it requires one copy from each parent. If two such persons have babies, all of the babies will have dry ear wax. 
     If you used ear wax to define your races instead of skin colour think of the consequences! Instead of racialist-inspired studies purporting to show the link between skin colour and IQ, you might find studies showing a link between dry ear wax and lower IQ.
     But these are all examples of 'neutral' traits, that probably don’t contribute to an individual's survival. Is there any more or less variability in potentially lethal genes or gene combinations? The relationship between the disease malaria and one known as sickle-cell anemia is one well-known example. 
     Malaria is a deadly disease that's prevalent in the warmer latitudes. It's caused by a very hardy parasite that destroys healthy red blood cells, those that transport oxygen throughout the body. Sickle-cell anemia is caused by a gene variant that directs the body to make abnormal, sickle-shaped, red blood cells.
A 'sickled' red blood cell

     Carrying one normal and one sickling gene variant means that, when infected with malaria, the parasite is unable to find enough normal red blood cells to allow it to flourish and debilitate the host. Carriers display no symptoms of anemia, and they are not significantly debilitated. In a malaria area, having one copy of the sickling variant is  advantageous. For offspring to develop sickle-cell anemia, they must inherit one copy of the sickling variant from each parent. The odds of this happening are about 1 in 4.
     In areas where malaria is common, the sickling variant occurs in a high proportion of the population because those without it tend to die before they're able to produce offspring, leaving more carriers to pass on their sickling genes. Where malaria has little or no effect on populations, that sickling variant settles in the population at a very low frequency, perhaps as a commonly recurring, usually non-lethal mutation.
Piel, et al. Nature Communications, 1:104, 2010 (DOI: 10.1038/ncomms1104)
     Map b, above, illustrates the percentage of people in the population who have at least one copy of the sickling variant. Map c shows the level of malaria occurrence. Central equatorial Africa has the highest incidence. Compare the two distributions, and notice how the areas of high gene frequency 'map' on to the pattern of malaria prevalence. 
     The further away you get from the areas of highest incidence, the lower the frequency of the sickling variant in the population. Note, also, that this sickling gene variant is present, in small proportions, across the traditionally defined races. And it even occurs, in very small numbers of people, in areas where malaria is not endemic. It is only seen in higher frequencies in the presence of malaria. 
     The take-home message here is that there's much more variability in the human genome than can be accounted for by racial classifications. Genetic traits just won’t behave according to the prescriptions of a racial worldview.