Then about 50,000 to 30,000 years ago, something happened to produce what paleoanthropologists call "behaviorally modern humans" (Bar-Yosef 2002; Hill et al. 2009; Klein 2009). Their anatomy was the same as earlier humans, but their behavior showed a stunning increase in their mental complexity and abstraction. They were able to migrate out of Africa, and by about 20,000 years ago, they had migrated throughout Eurasia, Australia, North America, and South America. This began the human dominance of the whole planet. Their tools become more complex and sophisticated. Their ornaments became more abstract and esthetically evocative. Their art showed a distinctly human sense of beauty, as in this cave art:
An atlatl amplifies the human throwing motion so that the bolt (or dart) is launched to greater distances, higher velocities, and more penetrating power than thrown stones or hand thrown spears. Originally, the atlatl was invented by humans to be a weapon for hunting wild game, but then it could be used as a weapon against other humans in war or to punish cheaters and free riders, and thus to coercively enforce a larger scale of cooperation. Bingham estimates that while thrown stones and javelins could enforce cooperation among up to 90 individuals, atlatls could expand this tenfold up to 900 individuals.
Bingham argues that this expanded the range of cooperation because this new weapon allowed law enforcement to encompass a larger group of people, which then increased the scale of information sharing. This increase in cultural information sharing could then cause all of the other increases in inventiveness and complexity that characterize the behaviorally human revolution--including more complex tools, abstract art, and more intricate human artifacts.
Bingham's theory makes falsifiable predictions that can be tested against the archaeological evidence. For example, it predicts that the appearance of atlatls in the archaeological record precedes the appearance of the many traits of behavioral modernity.
The throwing stick and the bolt shaft of the atlatl are normally made mostly of wood and therefore likely to perish over thousands of years. But some apparently atlatl fragments made of bone, antler, or ivory have been dated to around 16-17 thousand years ago--such as the fragment from El Miron Cave pictured above (O'Driscoll and Thompson 2018; Morales and Straus 2008).
The oldest indirect evidence of atlatls come from the sharp stone points that have the shape and size that identify them as atlatl bolt points rather than thrusting spear points or arrow points. Thrusting spear points are larger and heavier than bolt points, which are larger than arrow points. Some of the oldest bolt points have been dated at 50 to 40 thousand years ago (O'Driscoll and Thompson 2018; Shea 2006; Shea and Sisk 2010).
John Shea--Bingham's colleague at Stony Brook University--sees some evidence of bolt points in sub-Saharan Africa as early as 100,000 years ago, although they become more common after 50,000 years ago. Shea admits, however, that he is baffled by the fact that historic hunter-gatherers in Africa have not used the atlatl. It's perplexing if atlatls were used in prehistoric Africa but not later.
Shea thinks Bingham has part of the puzzle for human evolution, but not all. Shea thinks the technology of the atlatl is not enough to explain human complexity, and that spoken language is a crucial factor. By contrast, Bingham thinks the evolution of human non-kin cooperation supported by coercive weaponry to manage the problem of conflicts of interest created the conditions for the evolution of language: non-kin cooperation was the cause, language was the effect (Bingham and Souza 2009, 240-76). I am inclined to agree with Shea that while the technology of projectile weapons is one critical factor in shaping human evolution--for the reasons indicated by Bingham--it cannot be the only prime cause.
Here's a video of John Shea showing how ancient atlatls were made and used:
One of the most conspicuous signs of behaviorally modern humans is the construction of huge earthen mounds that apparently were used for local gatherings, perhaps seasonally. Here is one of the Hopewell mounds in Ohio:
Hopewell burial mounds often have symbolic artifacts.
These symbolic artifacts were clearly traded over vast distances, and so they probably functioned as currency for exchange. Symbolic objects can serve as a form of money because they are precious and difficult to counterfeit. They can also be worn as ornaments or be signs of status, just as gold, silver, and diamonds can be both currency and valuable ornaments in our culture.
The economic trade in such valuable objects would have been impossible without some coercive law enforcement with weapons like the atlatl to punish thieves and cheaters and thus securing the rights of property and contract.
The evidence for such trade over 100,000 years or more refutes Friedrich Hayek's claim that market exchange is a recent invention in human history. On the contrary, we might conclude that Adam Smith was right in seeing that human beings are economic animals who naturally strive to "truck, barter, and exchange."
Some of my posts responding to Hayek and defending the idea that the extended order of liberal capitalism appeals to our evolved human nature can be found here, here, and here.
Bar-Yosef, Ofer. 2002. "The Upper Paleolithic Revolution." Annual Review of Anthropology 31: 363-93.
Bingham, Paul, and Joanne Souza. 2009. Death from a Distance and the Birth of a Humane Universe. Charleston, SC: BookSurge.
Hill, Kim, Michael Barton, and A. Magdalena Hurtado. 2009. "The Emergence of Human Uniqueness: Characters Underlying Behavioral Modernity." Evolutionary Anthropology 18: 187-200.
Klein, Richard G. 2009. The Human Career: Human Biological and Cultural Origins. 3rd ed. Chicago: University of Chicago Press.
Morales, Manuel R. Gonzalez, and Lawrence Guy Strauss. 2009. "Extraordinary Early Magdalenian Finds from El Miron Cave, Cantabria (Spain)." Antiquity 83: 267-81.
O'Driscoll, Corey A., and Jessica C. Thompson. 2018. "The Origins and Early Elaboration of Projectile Technology." Evolutionary Anthropology 27: 30-45.
Shea, John J. 2006. "The Origins of Lithic Projectile Point Technology: Evidence from Africa, the Levant, and Europe." Journal of Archaeological Science 33: 823-46.
Shea, John J., and Matthew L. Sisk. 2010. "Complex Projectile Technology and Homo sapiens Dispersal into Western Eurasia." PaleoAnthropology 2010: 100-22.