Warm-adapted Neanderthals in northern France

In posts published today, Alex Steenhuyse and John Hawks both link to this short article in The Independent about a new Mousterian site at Caours, France, near the shore of the Channel.

The interesting features of this specific site are its age, its geographical location and its contents. As concerns its age, it is reported to be about 125,000 years old, which puts it at the warmest moment of the last glacial cycle. As concerns its geography, it is located relatively far north, implying that Neanderthals were able to exploit northerly regions at least during those times when climate was favorable (also a conclusion of various paper in Van Andel and Davies [2003]). As concerns its contents, the site contains the bones of elephant, rhino, aurochs, wild boar, and various kinds of deer, and those apparently "show signs of having been sawn through, crushed or stripped of their meat by flint tools." This suggests that Neanderthals successfully acquired and processed these animals very early on.

The key word here is "acquired." To the "Neanderthal good" camp, this will be taken as evidence of hunting, which in turn - given the size of some of those beasties - strongly implies cooperative hunting and considerable planning depth. To the "Neanderthal bad" camp, this evidence (especially since it comes from a riverine context) will be taken as merely one more instance of Neanderthal opportunistic scavenging, with dead animals being washed down the river after dying of natural, non-human causes and the more-or-less putrefied corpses being butchered by grunting cavemen. I suspect that when the actual report for this site comes out, it will contain a detailed zooarchaeological analysis of the remains that will be used to support one or the other scenario. In the meantime, I just want to point out that the Independent article mentions specifically that the remains "include a small fragment of elephant bone, several rhinoceros teeth, and many remnants of aurochs, wild boar and several kinds of deer" (my emphasis). Maybe this will turn out to be primarily a hunting camp, with some scavenging of the largest animals? Then again, since it's unlikely folks (Neanderthal or modern) would drag a whole elephant carcass back to camp, maybe not... This is another example of people with different perspectives taking the same evidence to make it agree with what they believe. However, in this case as in any other, the empirical burden usually does agree better with some perspectives.

Another interesting feature of this article: the way it portrays Neanderthals. Contra popular tendencies, Neanderthals are not described as "evolutionary dead-ends". On the contrary, they're described as "our tough and resourceful, near-human, European predecessors" who were "known to be squat, powerful people, who had language and fire and buried their dead." That's a relatively far-cry from the descriptions of Neanderthals in the popular press over the past several years... hey, maybe reporters are finally starting to get it?

References:

Van Andel, T. H., and W. Davies (eds.). 2003. Neanderthals and modern humans in the European landscape during the last glaciation: archaeological results of the Stage 3 Project. McDonald Institute for Archaeological Research, Cambridge (UK).

La bataille aurignacienne continue... encore et toujours!

The Palanth Forum has a post that presents the contents of the 45th volume of the Trabalhos de Arqueologia monograph series of the Instituto Português de Arqueologia. The reason I bring this up in this blog is that the title of the volume (edited by O. Bar-Yosef [Harvard] and J. Zilhão [Bristol]) is Towards a Definition of the Aurignacian. It's based on a small conference that was held in Lisbon in 2002, organized by the editors of the volume, one assumes to clarify what is meant by the term "Aurignacian," a cultural label/period/technocomplex/what-have-you. This is an important issue because the Aurignacian has, perhaps aptly, been described as the "promiscuous handmaiden of Paleolithic archaeology" by one prominent researcher, because of the tendency of many people to make the Aurignacian be whatever the hell they want to support their view of the Middle-Upper Paleolithic transition.

I've read some of the papers in this volume, and most are quite interesting. However, one can well wonder whether this book will, in the end, really end the bataille aurignacienne that started in the early years of the 20th Century with the work of the Abbé Breuil, among others. One of the reasons behind this question is that most of the authors who contribute chapters to the effort already have well-known stances on what the Aurignacian is, how and where it originated, and what its relation to previous European industries was. Then, there's also those researchers who seem to consider that the Aurignacian is unproblematic to identify anyway and who just talk about it without even addressing the issue that is central to the volume. I think that it's emblematic that some of the most thought-provoking papers in the lot that I've had the chance to read so far come from the youngest researchers. There's also a heavy emphasis on continental European perspectives, with only two papers coming from researchers espousing an explicitly anthropological archaeological perspective. That's not necessarily a bad thing, to be sure, but given that many of the interpretive divergences concerning the Aurignacian appear to get somehow amplified over the Atlantic, a more even balance of viewpoints might have yielded different insights into the question.

In the end, I think that this volume will be very useful in highlighting what, in 2006, different people think the Aurignacian is, but perhaps not so much in terms of coming up with a widely shared definition of that phenomenon. Regardless, it should be very useful reading for anyone interested in the topic of the Middle-Upper Paleolithic transition and/or the emergence of behavioral modernity outside Africa.

Incidentally, the Palanth Forum is an interesting discussion board where a lot of interesting material gets posted or publicized. Well worth checking out, although the action there has unfortunately been kind of slow lately.

New online thesis database

I just downloaded a full-length thesis as a pdf from the "thèses-en-ligne" website, which is maintained by the French CNRS as a host for doctoral theses based on multidisciplinary research. There are over 5,000 theses available, including a number having to do with, among other things, prehistory and paleoenvironments.

I think this is a brilliant initiative that should serve as a model for other countries. First, it gives doctoral research a wider diffusion than it might otherwise get, especially given the difficulties of procuring theses from overseas for the Interlibrary Loan services of many North American universities. Second, it actually gives publicly-funded research entities an actual, concrete output which citizens can freely access. Lastly, it also forces some transparency in research results (i.e., people can finally check and see whether a PhD thesis really contains a meaningful discussion of certain issues), and it responsabilizes up-and-coming researchers by ensuring that they give back to the funding agencies that financed their work.

I think that, in the US, the NSF should start something like this, and that any public funding for doctoral research should be awarded only if the researcher agrees to provide NSF with a copy of the finished thesis. The same should also be true for the Canadian SSHRC and NSERC.

In any case, the CNRS initiative joins those of a number of other groups that wish to provide access to theses having to do with specific kinds of research. The Paleoanthropology Society's Dissertation Distribution Service is a good example. It is to be hoped that more research societies begin similar efforts

The oldest child...

The National Geographic web site has a story about a 3.3 million-year-old infant skeleton found in the Dikika region of Ethiopia by a team of researchers led by Zeresenay Alemseged of the Max Planck Institute of Evolutionary Anthropology's Department of Human Evolution, in Germany. The site features some video and additional photographs, as well as a link to a much more detailed report about the find, and its implications for understanding development at that period of our past. Here's a shot of the skeleton which, unlike Lucy, has an almost complete cranium!

(Copyright: National Geographic Society;
source: http://www9.nationalgeographic.com/ngm/dikikababy/gallery7.html.)

This story has been a long time coming, since the first remains were originally found about five years ago, so it's nice to finally have a relatively detailed and well-illustrated report on the finds!

Added 20/09/2006, 15:03: The remains are also the subject of two new papers in Nature. Both can be accessed from this webpage which provides additional information.

More on Finlayson et al. (2006)

Just a brief note to point out that Alex Steenhuyse also has posted some interesting comments on his blog about the Finlayson et al. (2006) paper on late Neanderthal dates at Gorham's Cave. He draws some interesting parallels between this paper and the Gravina et al. (2005) paper on new dates for the site of Grotte des Fées de Châtelperron that was published last year. BTW, you might also want to check out Alex's website (Anthrosite), which contains info on his research on the Middle-Upper Paleolithic Transition in France, and some of his publications and ongoing research. Good stuff, good stuff.

It's also interesting to note that all of the in-depth comments on the Finlayson et al. (2006) paper that I've seen on the blogosphere (yikes, I just used that word!) so far have been rather skeptical...

References:

Finlayson, C., et al. 2006. Late survival of Neanderthals at the southernmost extreme of Europe. Nature: in press. doi : 10.1038/nature05195

Gravina, B., P. Mellars, and C. B. Ramsey. 2005. Radiocarbon dating of interstratified Neanderthal and early modern human occupations at the Chatelperronian type-site. Nature 438:51-56.

Bonn Conference Pre-Prints

2006 marks the 150th anniversary of the original Neanderthal type-specimen discovery at Feldhofer Cave, in the Neander Valley, in Germany. To commemorate the discovery that set the stage for much of today's paleoanthropological research, a major international conference was held in Bonn, Germany earlier this year, where some of the most prominent researchers in the field of "Neanderthal studies" presented reviews and new discoveries.

The full program, complete with extensive abstracts (each several pages long), have been made available as a pdf file on the Istituto Italiano di Preistoria e Protostoria's web site. It's a pretty big file, but well worth the hassle to get an idea of the currently dominant stances and perspectives about Neanderthals today.

The scientific method...

Courtesy of PhD Comics by Jorge Cham (which I warmly recommend reading).

Should I be concerned that I found this comic so damn funny...?

Tragedy in Montreal

The tragic shooting spree that happened yesterday in Montreal took place at my sister's school. She was outside the building when it happened, and escaped uninjured although she is badly shaken. I'm so relieved she's safe, you have no idea. This is a tragedy, nothing less, and I feel overwhelmed right now. My thoughts go out to the injured and the families of the deceased student and the nineteen other people that were injured, some critically. It's a dark day.

The latest of the last?

Through the magic of the information superhighway, I managed to get a copy of Finlayson et al.'s (2006) paper that I mentioned in my last post. It's pretty short, and I've had time to go through it in depth.

At its most basic, this is a schematic site report focused on chronology as derived from AMS 14C dates, of which the authors present fully 30. There's unfortunately little to no discussion of the lithic or faunal assemblages (presumably because that information will be included in the project's final report/publication), so there is almost no information about the patterns of mollusk and sea mammal exploitation in the Mousterian levels of Gorham's Cave, which I was originally so excited about, based on comments by Finlayson on the Nature news report.

The main of the paper is an argument for an age of ca. 28,000 radiocarbon years (that is, uncalibrated) for the Late Mousterian at Gorham's, and that there is no evidence for infiltration from the overlying Upper Paleolithic (Solutrean and Magdalenian) level III into Mousterian level IV. That these two form discrete and well separated depositional units is well demonstrated by a combination of two measurements of “geochemical detrital ratios”, in this case K/Al and Mg/Al, which indicate radically different depositional contexts for levels III and IV (Finlayson et al. 2006: Figure 1c). So, the late MP and UP levels are clearly distinct, no argument there, and this is further suggested by a photograph (Figure 1d) of a section at the site which leaves little doubt as to the dramatically distinct sediment color in each.

As for the dates themselves, the 22 that concern the Late MP level (samples 9-30) are a bit hard to make sense of at first glance, especially since the authors present doubled, rather than single error ranges. Now there's absolutely nothing wrong with doing this; in fact, given their large corpus of dates, it's probably better to do so, since it means that all the radiocarbon determinations thus presented are ca. 95% likely to correspond to the range within which an individual sample's actual age falls. However, it does lead to a bit of confusion since dates are usually presented with single error ranges.

Regardless, even at second glance, the chronological data are very messy, and as a whole they display no obvious logical stratigraphic coherence, although they all fall somewhere between ca. 24-32,500 uncal. BP, distibuted over about 50 cm of sediment. Finlayson et al. explain this general lack of coherence as resulting from

“repeated use [of the site] confirmed by the stratigraphic distribution of the dates within level IV that indicate localized alterations due to use and reuse (for example trampling and cleaning) in the area around the position of the hearths but dates in stratigraphic sequence within the location of the hearths themselves. Thus, three samples (16, 17 and 20; Fig. 1) came from Mousterian superimposed hearths. These three dates provide a stratigraphic sequence from 24,0106320 to 30,5606720 yr BP. Taken together, all the dates show that Neanderthals occupied the site until 28 kyr BP and possibly as recently as 24 kyr BP.” (2006:p.1).

In other words, they explain away 19 of their dates that are not in coherent stratigraphic order by focusing on only three of them that are coehrent and suggest a very young age for the Mousterian deposits. Their argument for this (i.e., focus at the center of the heart which remained in a fixed position throughout the Mousterian at the site), while certainly valid is also somewhat problematic. For one thing, the majority of the bottommost dates (i.e., samples 24-27 and 30) display a coherent age of roughly 31-32.5 kya uncal for the base of the deposit, and this even well away (i.e., roughly 4 meters) from the hearth which is supposed to be the epicenter of disturbance. Embedded between them are samples 28-29, which date to (ironically) 28 and 29 kya. If anything, given that these two samples come from immediately next to each other (as best as can be gauged from Figure 1c), their unexpected recent ages are perhaps best explained by some unspecified localized form of contamination. So, overall, the very base of the hearth would seem to date to somewhere between 31-32.5 kya, thus providing a terminus post quem (or ante quem, depenging on your take) for the age of overlying samples. The four stratigraphically highest samples (9-12) give ages ranging from 26-30 kya (with an average of around 28.5 kya), which is coherent with the minimum age of the Late MP deposits just outlined. I think that this is basically where the data presented leaves us at this point, however. And what is known so far should, in the absence of evidence to the contrary encourage us to lean towards an older age for the top of the Mousterian (i.e., closer to 30 kya than 26 kya).

I think that the argument that the dates should all be considered valid but in secondary context because people continued using the site for prolonged periods and moved stuff around is not very good for two main reasons: First, this is likely to have been the norm at many cave/rockshelter sites whose physical characteristics (e.g., the presence of a high vault, or ceiling openings to enable smoke to clear out) would have constrained the positioning of certain features such as hearths. This is certainly something I've observed in my own field work, where Mousterian and Aurignacian hearths were located at the same spot in the rockshelter. Should we suppose that Italian Pleistocene hominins were more mindful about kicking stuff around and/or digging around than those from Gibraltar? Or that they operated with more of a concern for future archaeologists? I don't think so. This being the case, the argument that people lived in sites and must have disturbed sediments and the position of dating samples is unconvincing and basically a post hoc argument that has little inherent merit. There are ways to demonstrate the integrity (or lack thereof) of given layers within archaeological sites (e.g., micromorphology) and in their absence, it is simply impossible to accept the argument for anthropogenic (or any other source) sedimentary disturbance at face value. Maybe this information will be provided in the final report, but at the moment, it's lacking.

The second line of evidence against the explanation for mixing has to do with the intensity of occupation at the site. The authors report a total of 103 lithics for level IV, which was excavated over an area of 29 square meters. The site stratigraphy presented in the paper indicates a thickness of about 1m for level IV, which means that we're dealing with a density of about 3.55 lithic artifacts per cubic meter of excavated sediment! Even if we take only the top half of the deposits (ca. 50 cm thick), that still only gives about 7 lithics per cubic meter. Practically, that means that, digging a 1x1m unit in 10 cm spits, one would encounter one lithic per spit, 7 times out 10! In my view at least, this is hardly the kind of evidence of very intensive use and reuse of an area, especially around a hearth, where lithic concentrations tend to be relatively dense in general. So the argument for heavy human action on the sediment is, as a result, severely weakened. A caveat to this argument, however, is that it is unclear from this paper what is considered an artifact. Are we only talking about retouched tools here? Or are we (as I assume) including debitage as well? What's the frequency of retouched pieces relative to the total? This is information that could significantly clarify the discussion about site occupation intensity. Again, I suppose we'll have to wait for the final report to be sure.

So, in the end, is this site really 28 ky or even 24 ky old? As is usually the case in paleoanthropology, it's not impossible. However, in light of the reasoning just outlined, I think that the possibility of sample contamination should be dealt with in a more thorough fashion before being discarded out of hand. At the moment, I'm not unwilling to consider that the top of the sequence may be as old as 28.5 ky old, but my money's still on a slightly older age, probably along the lines of 30 kya. What would have considerably clarified the issue here would have been the presentation of the results of complementary dating methods (e.g., TL, OSL, ESR). This would have enabled an objective discussion of whether or not the sediments were really disturbed or if the charcoal samples might have been contaminated by younger material at some point.

Check out also John Hawks' blog for some additional comments on the paper.

References:

Finlaysn, C. L., et al. 2006. Late survival of Neanderthals at the southernmost extreme of Europe. Nature: in press. doi:10.1038/nature05195

The end of the Neanderthal world... geographically!!

It's all over the web!
There's an article in the New York Times
about a soon-to-be-published report by Clive Finlayson's team on new radiocarbon dates from Gorham's Cave, Gibraltar, that seem to indicate that some Mousterian tools at the site date to 28,000 BP. The NYT piece is based on a paper that should come out soon in Nature, but so far, all that's available is this news report by David Brill, titled "Neanderthal's last stand." The NYT piece also refers to a commentary by Eric Delson and Katarina Harvati to be published along with the Nature paper, in which they stress caution, but nonetheless suggest that the date seems convincing.

The news report doesn't have much more detail, except a mention that the assemblage (or is it the retouched tools?) is composed of 103 artifacts, and that the site has yielded evidence for extensive exploitation of sea resources (shellfish and mammals!). There's a comment in the news report by Paul Mellars, who rightly mentions (yes, yes... I just wrote "rightly"!) that we must be somewhat wary of the dates because minute amounts of contamination might have affected the resulting dates. However, there's no way to tell before reading the piece whether this is an issue (I suspect it's not... they probably have multiple AMS dates can be done on extremely small samples).

A few comments:
1) These are only tools that are dated; there's no associated fossils, although only Neanderthals are known t have manufactured Mousterian industries in Europe.

2) The evidence for sea mammal harvesting (in the form of scavenging) is some of the first of its kind for a Mousterian site; that, to me, is perhaps the neatest aspect of this news so far!

3) Purely coincidentally, I finished reading Finlayson's Neanderthals and Modern Humans (2004) volume today. Overall, I liked it quite a bit, especially because it takes such a refreshingly different perspective from most research on Neanderthals and modern humans (he actually formulates test hypotheses and contrasts them to the known record, as oppose to just describing the record!). It's a bit environmental deterministic, but it's very well done... too bad people don't seem to have picked up on it too much yet... hopefully this new paper will change that!

More thoughts after I've found the paper itself!

New posts soon!

Apologies for the recent lack of updates, and expect some new posts in the extremely near future. Got back from te UISPP meetings in Lisbon where a grand time was had. I'll be writing more about that (and other topics) very soon, so check back in a few!

New PaleoAnthropology papers

PaleoAnthropology,, the official publication of the Paleoanthropology Society, has a number of new reviews and papers out, as of yesterday (methinks). The papers are available for free in pdf format. Look for some thoughts on the piece entitled "Eco-Cultural Niche Modeling: New Tools for Reconstructing the Geography and Ecology of Past Human Populations " in the near future. Time has been kind of tight lately, but I'll be posting more very soon, so keep posted!

Update on Creswell Crags

There's a short online report detailing the results of recent excavations at the British rock art site of Creswell Crags. Given that the team was digging up the spoil heap of 19th Century excavations that took place at the site, it's perhaps not surprising they didn't find too much. What they did find, however, covers the range from the Middle Ages all the way to the Gravettian. The exact nature of all Pleistocene chronological attributions is unclear.

Not terribly informative as to exactly what was found, tool-wise, aside from a potential Pleistocene awl, though the report includes this tentalizing if vague excerpt:

"There was one possible find of Ice Age art, which researchers will be examining further, and the excavation will provide the archaeologists with enough information to plan a further major dig at the site next year."

The report does include a neat image showing the outline of some of the engraved stags identified in 2003 and 2004.

Study break of sorts

I'm in Genoa until mid-September, studying Paleolithic lithic collections from Riparo Bombrini with my colleague Fabio Negrino, but I have web access so I should keep posting relatively regularly.

While in Europe, I'll also take a week off to attend the quinquennal UISPP meetings in Lisbon, Portugal, where I'm presenting papers on aspects of my doctoral research. The full program of the 2006 meetings is now available online in pdf format on the conference website and, for anyone with an interest in prehistoric research in the broadest sense, it's sure to be a treasure trove of information, since the abstracts are included as well. Individual sessions, such as Setting the Record Straight: Toward a Systematic Chronological Understanding of the Middle to Upper Palaeolithic Boundary in Eurasia also have individual web pages, or more detailed information in pdf format. Should be a great conference, and Lisbon, well, is Lisbon!

Henri de Monfreid, archaeologist

Reading through a paper by David Pleurdeau "in press" in the African Archaeological Review, I stumbled upon a reference to the original discoverers of Porc-Epic Cave, a Middle Stone Age (MSA) site in Ethiopia. Almost everyone interested in the MSA of East Africa knows that P. Theillard de Chardin (1930) was one of them (see also Pleurdeau 2005); fewer know that Henri de Monfreid was the other. Fewer still probably know about Henri de Monfreid, a French expat (mainly) who lived an adventurous life on and along the coast of the Red Sea, trafficking in weapons and other things, and doing a number of things often not completely within the bounds of the law. As it happens, Monfreid was also a very talented and prolific writer who captured a number of his experiences in written form. The first Monfreid book I had the pleasure to read back in 1994 was La croisière du Hachich, translated into English under the title Hashish (a fantastic read!), and I've been hooked ever since, reading compulsively anything of his I've come across over the years. A good overview of Monfreid's life and artistic output (he was also a painter) is provided by P. Baraduc in his Henri de Monfreid: Flibustier de la Mer Rouge (1998).

He is, hands down, one of my favorite writers, and it was a small pleasure to learn that he had, on top of all else he did over his lifetime, done paleoanthropological and ethnological work.

References

Baraduc, P. 1998. Henri de Monfreid: Flibustier de la Mer Rouge. Collection "Grandes aventures." Arthaud, Paris.

Monfreid, H. de. 1933. La croisière du Hachich. Grasset, Paris.

Pleurdeau, D. 2005. Le Middle Stone Age de la grotte du Porc-Épic (Dire Dawa, Éthiopie) : gestion des matières premières et comportements techniques: Porc-Epic cave (Dire Dawa, Ethiopia). L'Anthropologie 107:15-48.

Pleurdeau, D. 2006. Huma technical behavior in the African Middle Stone Age: the lithic assemblage from Porc-Epic Cave (Dire Dawa, Ethiopia). African Archaeological Review 22: in press. (DOI: 10.1007/s10437-006-9000-7)

All Mellars, all the time

Paul Mellars is enjoying a rather prolific year, as far as publishing review papers in high-profile journals is concerned. The latest one can be found in Science and concerns the archaeological evidence from southern Asia between 50 and 30,000 BP. Unsurprisingly, Mellars argues that these artifacts provide indisputable evidence for the dispersal of (not to say the colonization of the Old World by) anatomically and behaviorally modern humans. Now, there's things I like about this papers, and things I dislike.

On the “like” side, Mellars present evidence from an area that is largely unknown (and therefore undiscussed) by most researchers concerning themselves with modern human origins research. This therefore exposes the rest of the discipline to data that offer the potential to confirm or contradict current ideas and models. This is done in his usual concise and engaging style, which is not something that is given to all paleoanthropologists to be able to do.

On the “dislike” side, Mellars once again (see Mellars 2006a) implicitly presents archaeology as simply an ancillary line of evidence to be at worst fitted to or at best compared to the conclusions reached by seemingly serious disciplines like evolutionary genetics and human paleontology (see discussion in Marks 2003). This, in my view, seriously demeans archaeology as an independent field of study which has a lot to offer. I think part of why Mellars perhaps unwittingly depicts archaeology in such a way has to do with his approach to archaeology. For him, archaeology is largely a culture-historical exercise, meaning that the goal of archaeology is to track the extant and duration of given “cultures.” From this perspective, artifacts are not so much objects that were used by prehistoric hominins to achieve given ends but signals of group identity. In this sense, a Dufour bladelet, say, becomes simply the Paleolithic equivalent of a coin of a given age and provenience in numismatics.

As I've said before, this is not inherently wrong, and some artifacts unquestionably have restricted temporal and geographical distributions. However, this perspective stands in stark contrast to the goals of anthropological archaeology and evolutionary ecology, which are to understand how people acted in the past and why. For anyone interested in evolutionary processes in the deep past, these are the questions that should matter. To simply plot the distribution of culture groups does nothing to explain the evolutionary storyline to which they belong, it merely sets the stage. It's like stating that a book comprises X number of chapters without explaining how the chapters are related and why one chapter comes to a close when and how it does. To me at least, this is very unsatisying.

Getting back to the paper itself, however, there are some more serious issues with some of Mellars' assertions. As concerns the genetic evidence for a single population diffusing from Africa, he brushes aside known problems with studies of mitochondrial and Y-chromosome DNA that potentially support the existence of two separate populations despite citing fully eight such critiques, which is no small number considering that he cites only seven studies in support of his argument. This is not necessarily critical, since studies are liable to criticisms even if they are not thoroughly flawed, but these numbers do give pause.

As far as the archaeology is concerned, Mellars makes his case for a direct link between Africa and southern Asia by presenting evidence that a handful of sites dated to between 30-34 kya (calibrated, which means roughly 27-31 kya uncal, which corresponds to the beginning of the Gravettian and not the Aurignacian in Europe!!) yielded “crescentic” forms and ostrich eggshell beads similar to a handful of African Howiesons' Poort (and Howiesons' Poort-like) assemblages dating to at most 65 kya. In passing, Mellars once again repeats his assertion that such lithics may have been parts of arrows, something which I have shown to be unsupported by any hard evidence in two previous posts (the first, the second). As concerns the lithics, the argument for analogy is unconvincing on two levels. On a purely empirical level, a casual inspection of the drawings of them presented by Mellars suggests that the majority of the southern Asian artifacts were made on flake blanks, which is a very different way to manufacture crescentic forms than the backing of blade segments that characterizes the African material. Further, Mellars presents no data whatsoever about the rest of the lithic assemblages to which these crescents belong. In the Howiesons' Poort of Klasies River Mouth, Wurz (2002) has shown “crescents” are present in the hundreds! They thus represent a central part of the assemblage. Unless the lithic assemblages from southern Asia can be shown to display a similar dependence on crescent technology, any argument about whether they represent the same “culture” or even more simply the same “way of doing things” is unsupported. Otherwise, one would have to say that the Uluzzian of southern Italy, which Mellars himself has repeatedly and unwaveringly assigned to Neanderthals (e.g., Mellars 1996, 2004, 2005), would have to be taken as proof positive of modern human expansion in that part of the world as well.

On a conceptual level, it is also very interesting to take a look at how Mellars attempts to present the case for a cultural connection between Africa and southern Asia. Rather than presenting any contextual data about the assemblages which he mentions, he limits himself to presenting composite pictures of “representative” artifacts from, on one side, southern Asia and, on the other, Africa. It doesn't matter that in both instances the assemblages invoked are separated by hundreds if not thousands of years and kilometers. A telling analogous argument is that put forward by Bradley and Stanford (2004) which alleges that the Clovis Paleoindian culture of North America derives from the influence of western European Solutrean migrants who would have crossed the Atlantic to settle the Americas. This argument has been debunked in press by a number of paleoanthropologists (e.g., Sellet 1998, Straus 2000, Clark 2004) and does not appear – to the best of my knowledge – to enjoy widespread credence among the archaeological community as a whole. Interestingly in the context of this discussion of Mellars' latest paper, however, in their latest paper Bradley and Stanford's discussion of actual artifacts is illustrated only by a set of three figures (2004:466, 467, 468) in which they present, on the one side, select Clovis artifacts and, on the other, Solutrean artifacts. Here too, there are no detailed discussions of the broader context in which these lithics are found, and no solid empirical data presented in tables to back up their argument. Rather, the similarities between the composite pictures are, in this case as well, argued to represent indisputable evidence of a direct link between the two. Except that in this case, nobody else no seems to be convinced, beyond perhaps the popular press which is always so eager to present “both sides of the debate.”

As Clark (2004:110-111) argues:

“Their scenario is an example of post hoc accomodative argument, wherein explanations are developed after an analysis has been completed (in this case, a very superficial one) to account for patterns detected in a data set. Post hoc accomodation is a weak form of inference because the research designs that incorporate it lack a deductive component... Post hoc accomodative argument sets the agenda for future research, rather than constituting a set of conclusions that can stand or fall on their own.”

I think that this relatively fairly describes the gist of Mellars' approach as well. Now, I'm not saying that post hoc accomodative arguments cannot be a good source of ideas, some of which may even be amenable to empirical testing. However, in this case, there is very little analytical depth to this and Mellars' other recent papers (2006a, 2006c), and no critical take on the data. Rather, Mellars repeats the same argument over and over again, incorporating only the data that fits his ideas. The problem is that such papers are then taken as gospel by other researchers who cite it as proof for a single-origin colonizing population of modern humans that blazed an ochre-stained trail out of their African homeland as they marched ineluctably to conquer the rest of the world. Contemporary archaeology can – and most importantly should – do more than this, and develop its own set of conclusions that can then be confronted to the human paleontological and genetic records rather than vice-versa.

References

Bradley, D., and D. Stanford. 2004. The North Atlantic ice-edge corridor: a possible Palaeolithic route to the New World. World Archaeology:459-478,

Clark, G. A. 2004. Deconstructing the North Atlantic connection. In The Settlement of the American Continent (C.M. Barton, G.A. Clark, D.R, Yesner, and G.A. Pearson, eds.), pp. 103-122. The University of Arizona Press, Tucson.

Marks, A. E., 2003. Reflections on Levantine Upper Palaeolithic studies: past and present. In More than Meets the Eye: Studies on Upper Palaeolithic Diversity in the Near East (A. N. Goring-Morris & A. Belfer-Cohen, eds.), pp. 249-264. Oxbow Press, Oxford.

Mellars, P. 1996. The Neanderthal Legacy. Princeton University Press, Princeton.

Mellars, P. 2004. Neanderthals and the modern human colonization of Europe. Nature 432:461–465.

Mellars, P., 2005. The impossible coincidence. A single-species model for the origins of modern human behaviour in Europe. Evolutionary Anthropology 14, 12–27.

Mellars, P. 2006a. Why did modern human populations disperse from Africa ca. 60000 years ago? A new model. Proceedings of the National Academy of Sciences 103:9381-9386.

Mellars, P. 2006b. Going east: new genetic and archaeological perspectives on the modern human colonization of Eurasia. Science 313:796-800.

Mellars, P. 2006c. A new radiocarbon revolution and the dispersal of modern humans in Eurasia. Nature 439:931-5.

Sellet, F. 1998. The French connection: investigating a possible Clovis-Solutrean link. Current Research on the Pleistocene 15:67-68.

Straus, L.G. 2000. Solutrean settlement of North America? A review of reality. American Antiquity 65:219-226.

Wurz, S. 2002. Variability in the Middle Stone Age lithic sequence, 115,000–60,000 years ago at Klasies River, South Africa. Journal of Archaeological Science 29:1001–1015.

More on interstratifications

There's a new paper in PNAS by J. Zilhão and colleagues which casts serious doubts on the empirical validity of claims by Gravina et al. (2005) for the presence of a Châtelperronian-Aurignacian interstratification at the site of Grotte des Fées de Châtelperron. This is the final version of a paper which was presented at the Paleoanthropology Society meetings in San Juan, Puerto Rico this past April, and John Hawks already has some good comments on it.

Empirically, there is little to argue with here, and the authors thoroughly and painstakingly debunk the evidence used by Gravina et al. (2005) in support of the alleged interstratification. They conclude that, by and large, the sequence at Grotte des Fées de Châtelperron appears to have been extensively disturbed postdepositionally and that its stratigraphy is too severely compromised for it to be used to reliably talk about the succession of Upper Paleolithic "cultures" in the area. The most damning evidence they bring to bear is the presence of typological diagnostics belonging to various technocomplexes in the layers that are at the center of the dispute. As well, there is indisputable evidence that carnivores accumulated the vast majority of the faunal assemblages of the site's levels germane to the debate, which given the dubious context of the lithics largely precludes their unambiguous association with human occupations at the site.

As concerns the lithic assemblages, they conclude that the scant number of retouched pieces relative to debitage (34.5% of the assemblage - a figure which is in actuality not all that low, but one that is consistent with the occupation of the site by residentially-mobile foragers or those on task-specific forays) and the extremely small number of Aurignacian diagnostics argue against interstratification. Most important, however, is the taphonomic study of the site's stone tools which clearly demonstrates that levels B1-3 are significantly disturbed, while levels B4 and B5 might be largely in place. Given this situation, it is more than likely, according to the authors, that the rare Aurignacian pieces (i.e., 5 pieces out of 237 total) are intrusive into B4. This is an excellent example of how taphonomic study of lithics can yield precious information about site formation processes and a further incentive for analysts to perform such studies in all contexts.

Overall, I like this paper a lot, and not only because it agrees with my colleagues and I's conclusions that Gravina et al.'s (2005) case is thoroughly unconvincing (Riel-Salvatore et al. 2006). This is the kind of critical evaluation of artifactual material that should go into any analysis of Paleolithic material, especially when dealing with such "hot button" topics as the Neanderthals' disappearance and/or their cognitve capacities. That said, as discussed in a previous post, I don't necessarily agree with Zilhão, d'Errico and their colleagues that these findings argues only for the 'indigenist' scenario of modern human origins. Considered in the broader context of Eurasia and of other kinds of interstratifications, the implications are much less straightforward than claimed in this paper. Specifically, with all the respect I have for the rigor of Zilhão and d'Errico's work and the important rejuvenation it has brought to 'Transition studies' so to speak, their perspective remains fundamentally a very culture-historical one where given artifact types can be equated directly with given "cultural" and even biological groups. While not inherently incorrect, this perspective largely discounts the fact that Pleistocene hominins made artifacts first and foremost to ensure their survival and maximize their reproductive fitness through the acquisition of the resources necessary to support them. I think that considering the transition from such an angle offers new, stimulating perspectives on the Transition that enable us to approach this evolutionary problem from the behavioral perspective necessary to cast it in the appropriate theroretical - and methodological - light.

References

Gravina, B., P. Mellars, C. Bronk Ramsey, 2005. Radiocarbon dating of interstratified Neanderthal and early modern human occupations at the Châtelperronian type-site. Nature 438:51-6.

Riel-Salvatore, J., A. E. Miller, and G. A. Clark. 2006. On the reality of a claimed Châtelperronian-Aurignacian interstratification at Grotte des Fées de Châtelperron (Allier, France). Paper presented at the 2006 Annual Meetings of the Paleoanthropology Society, San Juan, Puerto Rico.

Zilhão, J., F. d’Errico, J.-G. Bordes, A. Lenoble, J.-P. Texier, and J.-P. Rigaud. 2006. Analysis of Aurignacian interstratification at the Chaˆ telperronian-type site and implications for the behavioral modernity of Neandertals. Proceedings of the National Academy of Sciences 103:12643-12648.

New Predmosti finds

A recent report details the discovery, by Becky Farbstein of Cambdige University, of two small pieces of bone bearing incised lines at the site of Predmosti, in Moravia. Here's the only image of the finds I've been able to locate so far.

Accoridng to the timeline provided by the report (25-30 kya - no mention of whether this is in calibrated years BP), the finds would belong to the Gravettian (or Pavlovian, in East-Central Europe), an industry for which a rich body of artistic behavior is documented, especially in Moravia, where figurines, dolls, ornaments and rich burials are well-documented. Thus, two "thumbnail-sized" pieces of incised bone hardly represent a revolutionary find, though little new in the way of decorated artifacts had been found at Predmosti since the original excavations, about a century ago. Every little bit helps, though, when trying to understand the complexity of artistic behavior in the deep past. It'd be interesting to see if a similar find would have been published without additional expert commentary had it been made in Mousterian or even Aurignacian context...

The ongoing Kansas shuffle...

So, the Kansas board of education got a makeover again yesterday, as related in this story in the NY Times.

Seems like a good thing, at least for the short term... it'd be better if we could ultimately enact a more lasting solution than the current political see-saw between moderates and advocates of non-scientific approaches, however. Carl Zimmer has a good, interesting post on the ruling.

Be back soon!

Hey folks.
Sorry for the lack of updates. I'm back in AZ and currently in the throes of moving to a new place, which is monopolizing my time. I should be back posting regularly within a week or so.