A publication of the Archaeological Institute of America
Early shell beads from recent and old excavations push back the date for human culture
(Courtesy Marian Vanhaeren) [LARGER IMAGE]
A report in the journal Science this past June noted the discovery of Middle Paleolithic shell beads in collections made during excavation of sites in Israel and Algeria many decades ago. The evidence, combined with recent finds from South Africa of 75,000-year-old shell beads, is the earliest indication of "cultural modernity" among anatomically modern humans--with an origin in Africa of about 200,000 years ago. Before now, the earliest evidence for cultural modernity was from Europe and dated to around 40,000 years ago. ARCHAEOLOGY spoke with Marian Vanhaeren of the French Centre National de la Recherche Scientifique and a co-author of the Science report about this discovery.
In 2004, you reported finding 75,000-year-old shell beads at Blombos Cave in South Africa. Why did you go looking for similar evidence elsewhere?
There is a heated debate on when did we become culturally modern, that is when did we develop language, symbolic thinking, religion, etc. Personal ornaments, along with art, are unanimously seen as archaeological proof of the acquisition of those abilities. We thought until recently that personal ornaments were invented in Europe 40,000 years ago when people like us colonized this region of the world and replaced Neanderthals.
Two years ago, we discovered that the oldest beads came in fact from Africa where our species originated. They consist of 41 shell beads found at the South African site of Blombos Cave dated to 75,000 years ago. We published these finds in Science and a long article in Journal of Human Evolution with Francesco d'Errico, researcher at the French Centre National de la Recherche Scientifique, Chris Henshilwood, the Blombos site excavator, and Karen van Niekerk, University Cape Town, South Africa.
This finding however met the criticism that a single site was not evidence for a general capacity. It was for this reason crucial to work on other potential evidence for the use of personal ornaments both from old and new excavations.
You ended up looking at old collections from Israel and Algeria. Why those sites? Did you look at shells from other sites as well?
Modern examples of the N. gibbosulus shells (Courtesy Marian Vanhaeren) [LARGER IMAGE]
Chris Stringer, the well-known British paleoanthropologist, contacted Francesco d'Errico and suggested we should give a look at Skhul collection kept at the Natural History Museum (London) to see whether shells mentioned by the excavators Garrod and Bate in their 1937 report were still there and assess their anthropogenic/symbolic nature. In the monograph there is a table that mentions the presence of some shell species at Skhul but without specifying their quantity or provenance. Chris Stringer located the shells with the help of Jonathan Todd (curator of the malacology collection of the Natural History Museum). Francesco d'Errico and I went to the museum in December 2004 and identified the two Nassarius gibbosulus, one shell had a hole, the other was covered with concretions. Only after we cleaned it under the microscope--a long job, with demineralised water and a wooden tooth pick--could we see the concretion was in fact hiding a perforation similar to that on the other specimen. This was a moment of great excitement with all four of us together. As for the shell bead from Oued Djebbana, belonging to the same species as the ones from Skhul, I found the reference in the literature. Asking colleagues we found out that the collections from this site were hosted at the Musee de l'Homme in Paris. We visited the museum with little hope to find the shell considering its small size and the fact the site was excavated long ago. Almost miraculously the assistant curator in charge was able to locate the shell in the basements of the museum. At present we are working on material from North and South Africa that confirms our recent findings: beads are used in Africa and the Near East well before the Upper Paleolithic of Europe.
Since these beads were excavated in the 1930s at Skhul and the 1940s at Oued Djebbana, how can you confidently determine their dates?
We have much better evidence on the dating of Skhul than of Oued Djebbana. For Skhul, the chemical analysis, carried out by Sarah James (Natural History Museum) of the sediment adhering to one of the shells demonstrates that it comes from the layer that yielded the skeletons of anatomically modern humans and that is dated to between 100,000 and 135,000 years with three different methods (electron spin resonance, Uranium series, and thermoluminiscence).
For Oued Djebbana we only have an "infinite" radiocarbon date, which indicates the site is older than 35,000 years ago, but we don't know how much older. The dates obtained on other sites with similar stone tools (Aterian) suggest the site may be between 60,000 and 90,000 years old. We have also found by comparing the shells to modern representatives of this species, that they are significantly bigger, which supports their attribution to the last interglacial. This implies that they are al least 75,000 years ago.
The shell bead from Oued Djebbana, Algeria (Courtesy Marian Vanhaeren) [LARGER IMAGE]
Do you think there were many more shells that were just missed during excavation?
Probably yes, we know that the excavation methods at the time of the discovery of the Skhul and Oued Djebbana shells were not as precise as they are today and it is highly probable that more shell beads were simply not collected or broken considering the extreme hardness of the sediment at the Skhul site.
Sifting through dusty museum collections doesn't sound glamorous, but your finds illustrate how valuable this work can be. How important is it to maintain museum collections?
It is crucial! Keeping the archaeological collections and the accompanying contextual information in the best possible way offer to future generations of archaeologists the possibility to verify our interpretations and address new questions, and this with better analytical methods.
Why is the date and location of the shells so important?
The date and location of the findings are important because we would like to know when and how cultural modernity emerged. Was it a continuous or a discontinuous process? Are the large gaps in time and space that, for example, we find in Africa indicative of a discontinuous process or do they just reflect the present state of our knowledge?
What evidence is there that these shells were used for jewelry? Are there any other explanations?
First of all, the sites are far from the sea, in the case of Oued Djebbana up to 200 km, which means that they were taken there by humans. And secondly, we have studied hundreds of modern dead shells of the same species and the way they are modified by natural agents. We found out that similar perforations are rare and that the probability to pick up two shells as those from Skhul by chance is less than one out of a thousand. So either humans selected shells with this perforation on the beach or, more probable, they perforated them by punching the center of the shells' dorsal side.
In the case of Blombos we found clear traces of use on the shell beads. Unfortunately the state of preservation of the Skhul and Oued Djebbana shells is such that we cannot reach a definite conclusion as to the human origin of the wear. In other words our argument for their symbolic use is based on the remoteness from the sea, their low nutritional value, and the presence of unusual perforations.
You mention in the study that you experimented with making perforations in shells yourself. How do you know how the perforations were made in the past and how did you go about re-creating the process? What did you learn from the experiment?
We repeatedly produced the perforations observed on the archaeological beads by testing two techniques and using three types of tools: punching the body whorl [the largest section of the shell] through the aperture and from the outer dorsal side with retouched stone points, bone awls, and pincer claws of a small crab. In each case, we recorded the location, morphology, size and microscopic features of the resulting perforations. These experiments revealed that a number of combinations of the above techniques and tool types are rather ineffective (pincer claw or bone tool from the outside break the tool, stone tool through the aperture breaks the shell lip) and that the holes we produced by piercing the shells through the aperture with a bone tool were morphologically, morphometrically, and microscopically (microchipping of the outer shell layer around the perforation) compatible with those observed on the Nassarius from Blombos Cave, while those from Skhul and Oued Djebbana closely resemble the ones we produced by punching the outside of the body whorl with a stone tool.
Shell beads from Skhul, Israel (Courtesy Marian Vanhaeren) [LARGER IMAGE]
What does the wide distribution--from South Africa to Israel--of similar shell beads tell us?
It indicates that anatomically modern humans from Africa and the Near East created beadwork traditions well before their arrival in Europe and that there were modern human cultures in Africa quite early in time. Although it is a difficult issue to discriminate the social function of prehistoric beads, the fact that the same shell species and only a single bead type was used at Skhul and Oued Djebbana suggests in our view that their main, though certainly not exclusive, function was, as for known San societies, that of exchange media used in gift-giving systems to reinforcing reciprocity networks and ensure the survival of hunter-gatherer groups in times of stress.
In the context of the "big picture," human evolution, the fossil record, and archaeology, where do you see these shell beads fitting in and what is their significance?
Personal ornamentation seems to have emerged around the world at different times and perhaps for different reasons. Their presence attests the modern character of the human cultures involved; but their absence perhaps does not necessarily imply a different cognition.
What has the reaction been to this article?
As far as I know very positive and widely reported in the press. I think only a minority of people seem to remain sceptical.
What initially attracted you to archaeology? How did your career develop?
As far as I can remember I have always been attracted by archaeology, I guess it was the appeal of foreign worlds or the quest of our origins. At the end of high school I thought hard sciences were too "hard" and "humanities" a bit too "soft." Prehistoric archaeology and paleoanthropology are among the few disciplines that effectively combine hard science and humanities. I studied archaeology at the University of Leuven (Belgium) and specialised in prehistory, took additional master courses in social and cultural anthropology. Then I moved to Bordeaux were I became fascinated by the potential of personal ornaments, a category of the archaeological record that in my opinion had a lot to offer. I finished my Ph.D. in 2002 and continued my research on prehistoric personal ornaments in the frame of two years postdoctoral fellowship in Paris and a one-year fellowship in London. Finally, I joined the French Centre National de la Recherche Scientifique as a researcher in prehistoric archaeology in 2006.
Do you think being a woman in this field is an advantage or disadvantage?
In western societies women wear more personal ornaments than men. We are perhaps more sensitive to the plurality of meanings and values involved in bead making and use. Therefore in my particular field of study it is perhaps more advantageous to be a woman.
What's next? Searching for more beads, or something else?
Undoubtedly, each new discovery of ancient beads has important implications for testing the unique versus multiple emergence(s) of symbolic thought. Also, the ability to produce and use beads is not peculiar of modern humans. Late Neanderthals also made and used beads. Are Neanderthal beads different in some way from those of modern humans? Were they used for the same purpose? These are the topics I wish to investigate in the near future.
But I think that beads may even offer more. They play different functions in different societies (e.g. they may be used to beautify the body, function as "love letters" in courtship, or as amulets, exchange media, expressions of individual and group identity, markers of age, class, gender, wealth, or social status). It may well be that the identification of these functions and the way they evolved to address specific needs is what is relevant for the debate on the emergence of cultural modernity more then the fact of finding or not beads. In other words when the time of the discovery will be over and a clear pattern appears we will need to refine our questions and find the real answers. I feel that they will have more to do with social processes than to human evolution.