Thursday, June 15, 2006

The origins of bow and arrow technology

The Mellars (2006) paper discussed in my last post is generating some discussion on the blogoshpere (see John Hawks’ blog, and Gene Expression) and on online forums (see the Palanth discussion forum), mainly on the case for bow and arrow technology, and its potential antiquity.

Let’s keep in mind exactly what Mellars actually says about this in his paper. Speaking about the new lithic forms that apparently characterize the Howiesoons’ Poort and Still Bay industries, he claims that:

"The possibility has been suggested that some of these forms could well have served as the tips and barbs of wooden arrows, based on comparisons with similar artifacts recovered from both later African Stone Age sites and much later Mesolithic contexts in Europe (McBrearty and Brooks 2000; Mellars 2002)." (Mellars 2006:9383).

Now, McBrearty and Brooks have certainly said in that paper (2000: 497, 503, 530) that some of these stone tools might represent barbs or arrowheads but they conclude only that “Whatever the details of their design, the Mumba and Howiesons Poort microliths support the presence of composite projectiles in Africa by 65 ka…” (2000:503). This is far from a demonstration that we are, in fact, dealing with arowheads at that time, and nowhere in that paper do they back that idea with any hard data.

In his earlier paper, Mellars (2002:37, 40) also definitely suggests formal similarities between some Middle Stone Age microliths and barbs from Mesolithic contexts at Star Carr. Again, however, beyond a general feeling that there exists a similarity, no empirical data are given to support this important contention.

The issue of bow and arrow technology is an important one in the debate over modern human origins and their alleged expansion out of Africa and colonization of the rest of the Old World. This is because if this technology is what gave modern human an edge however defined over the ‘archaic’ populations they would have encountered during their invasion of Eurasia, we would expect the evidence for it to be not only abundant, but also long-lasting. The bow and arrow are such a useful technological innovation that it is highly unlikely that they would have been forgotten at any point over the course of the Late Pleistocene. This is partly because of the great advantage they provide in hunting tasks and killing fellow humans, by enabling lethal wounds to be delivered from a great distance. This makes hunting of prey large and small much safer for the hunter and permits the hunters to get at prey from beyond their habitual flight distance for humans. Also, think about how versatile bows and arrows are: You have long, heavy compound bows in use by mounted warriors and hunters in the Central Asian plains and small, light bows used by foragers in tropical settings. In other words, bow and arrow technology can be made to fit the ecological context in which it is used without fundamentally altering its nature; this makes it an extremely polyvalent weapon system, so much so that it seems hard to believe that, if invented once and so crucial to the expansion of modern humans out of their African homeland, it would be forgotten or discarded.

Archaeologically, we have no unambiguous evidence for bows or arrows predating the latest Upper Paleolithic or even the Mesolithic. However, we also have no spearthrowers older than the one from the Solutrean occupation of Combe-Saunière (France), which dates to ca. 21,000 BP. This is in spite of now having abundant evidence that suggests that some pointed stone tools likely were used as dart tips much earlier than that date (Shea 2006). Thus, not having found remains of bows or arrows prior to the latest Upper Paleolithic does not de facto preclude their existence before that time.

So far, the best empirical study of the development of projectile technology in Africa and Eurasia is an excellent paper recently published in the Journal of Archaeological Science by John J. Shea of Stony Brook University. Shea uses measurements on the lithic components of known arrows, darts and spear to infer the most likely function(s) of various forms of pointed stone implements from Middle Stone Age, Middle Paleolithic and Early Upper Paleolithic assemblages from Africa, the Levant and Europe. Using Tip Cross-Sectional Area (TCSA) as the basis of his analysis, Shea shows rather convincingly that projectile weapons of the sort hinted at by Mellars and others do not appear to have been in use in the Old World prior to ca. 50,000 BP. And after that date, measurements align all Early Upper Paleolithic pointed stone implements with values for darts rather than arrowheads. Admittedly, the case for backed implements is less certain in that paper, but what data are available do not disagree with Shea’s conclusions. Therefore, the available evidence argues strongly against the case for bow and arrow technology having been an intrinsic component of the behavioral package that would have permitted the expansion of the original modern human populations.

So, while impressions are always useful in highlighting research questions to be tested empirically, they cannot be taken at face value as true statements, especially not in paleoanthropology. For some unfortunate reason, this habit of stating something and subsequently assuming that it is true continues unabated in Paleolithic archaeology while almost no Pleistocene human paleontological studies manage to get through peer-review without solid empirical data and meaningful statistical tests to support them.


McBrearty, S., and A. S. Brooks. 2000. The revolution that wasn’t: a new interpretation of the origin of modern human behavior. Journal of Human Evolution 39:453–563.

Mellars, P. 2002. Archaeology and the origins of modern humans: European and African perspectives. In The Speciation of Modern Homo Sapiens (T. Crow, ed.), pp. 31-48. Proceedings the British Academy, no. 106. London, UK, British Academy.

Mellars, P. 2006. Why did modern human populations disperse from Africa ca. 60,000 years ago? A new model. Proceedings of the National Academy of Sciences 103:9381-9386.

Shea, J. J. 2006. The origins of lithic projectile point technology: evidence from Africa, the Levant, and Europe. Journal of Archaeological Science 33:823-846.

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