The most recent Current Anthropology contains a paper by K. Szabó and colleagues (2007) about the behavioral implications of shell working dating back to 28-32 ky bp at Golo Cave, on Gebe Island (E. Indonesia). Here's the abstract:
"The evolution of anatomical and behavioural modernity in Homo sapiens has been one of the key focus areas in both archaeology and palaeoanthropology since their inception. Traditionally, interpretations have drawn mainly on evidence from the many large and well-known sites in Europe, but archaeological research in Africa and the Levant is increasingly altering and elaborating upon our understanding of later human evolution. Despite the presence of a number of important early modern human and other hominin sites in Southeast Asia, evidence from this region has not contributed to the global picture in any significant way. Indeed, the acknowledged simplicity of lithic assemblages has led generations of scholars to assume that Southeast Asia was far from the cutting edge of behavioural evolution. Comparison of sophisticated shell tools fromlevels dated to 32,000–28,000 b.p. in eastern Indonesia with lithic artefacts recovered from the same levels and an assessment of raw material procurement suggest that using lithic technologies as markers of behavioural complexity may be misleading in a Southeast Asian context and, indeed, may be hampering our efforts to assess behavioural complexity in global and comparative frameworks."
The paper contains a very good description of the distinct technological pathways followed by the Golo Cave hominins to fashion implements out of shell and stone. While their discussion is somewhat limited by the small sample sizes with which they had to deal (51 lithic artifacts, 14 shell artifacts), they do make a strong case that the two kinds of materials were worked in different manners. Further, they adequately emphasize that the worked shell material (i.e., the opercula of Turbo marmoratus, a marine snail) was collected through targeted procurement in subtidal or lagoonal waters - not opportunistically as an expedient alternative to stone. And this, they argue, represents evidence of "behavioral modernity" because materials that were not immediately available were not worked in the same way as stone, which was worked at Golo Cave in an essentially expedient manner. That is, material that was more difficult to obtain was worked more carefully than that which was easier to procure.
They present, in my view, a solid discussion about how different this kind of shell working is from that documented in the Mousterian of Grotta dei Moscerini (Italy), where shells appear to have been collected opportunistically and worked in much the same way as stone flakes. That said, I disagree with their implication that the shell working documented at Golo Cave really is evidence of "modern behavior", at least as they seem to be conceiving it. This is a point made well in I. Davidson's comment on the paper: Szabó et al. don't clearly define what they mean by "modern behavior" which makes it difficult to situate their argument in the broader debate about this issue. From the paper, I gather that they see modern human behavior as being qualitatively different from that of non-modern hominins such as, for instance, Neanderthals. This is why they discuss the differences between their case study and the Moscerini shell artifacts. Now, as I've said, there's no question that shell working at Golo and Moscerini are very different in nature. However, the subsequent implication is that this is proof-positive that Neanderthals were not behaviorally modern, at least not in the same way as the Golo Cave foragers.
This is where I disagree with them: their argument basically boils down to claiming the fact that the Golo Cave toolmakers treated hard-to-procure material in a different, more elaborate way than more easily accessible stone is evidence of modernity (and perhaps even of symbolic behavior, though this is simply stated and not discussed in any depth in this paper). In light of this, I just want to point out that there is plenty of evidence that Neanderthals managed (i.e., knapped) different kinds of raw materials in very different manners, even within single assemblages. Talking about what I know best, in the Mousterian (and Uluzzian) of the Salento peninsula, "formal tools" were much more often made on flint, chert and quartzite, which are not available locally (i.e., were most likely procured 100+ km away). Likewise, the whole operational sequence of production is usually not documented in those sites, implying careful management and transport of these prized mineral resources. Locally available limestones, in contrast, were frequently worked, by and large in very expedient manners. A similar, though not identical, situation is documented at other Mousterian sites where long-distance raw material procurement is documented, for instance at Champ Grand, in France (which I discussed previously here), where exotic materials are found mainly as heavily retouched tools that likely doubled as portable cores (Slimak and Giraud 2007).
All in all, Szabó et al.'s study is an interesting presentation of the different technological responses of Pleistocene foragers to different kinds of raw materials. As well, their desire to transcend the essentialism of the usual 'trait list approach' to the definition and archaeological recognition of "behavioral modernity" is laudable and one with which I am in fundamental agreement. However, if their argument for behavioral modernity at Golo Cave is accepted at face value, the implication is that Neanderthals were also behaviorally modern, in at least some (important) respects...
Slimak L., and Y. Giraud. 2007. Circulations sur plusieurs centaines de kilomètres durant le Paléolithique moyen. Contribution à la connaissance des sociétés néandertaliennes. Comptes Rendus Palevol 6:359-368.
Szabó, K. , A. Brumm, and P. Bellwood. 2007. Shell Artefact Production at 32,000–28,000 BP in Island Southeast Asia. Thinking across Media? Current Anthropology 48:701-723.