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HOME > PAST ISSUE > March-April 2011 > Article Detail

FEATURE ARTICLE

Refuting a Myth About Human Origins

Homo sapiens emerged once, not as modern-looking people first and as modern-behaving people later

John J. Shea

Abandoning a Myth

2011-03SheaF7.jpgClick to Enlarge ImageOne could view these findings as just another case of precocious modern behavior by early Homo sapiens in Africa, but I think they have a larger lesson to teach us. After all, something is only precocious if it is unexpected. The hypothesis that there were skeletally modern-looking humans whose behavioral capacities differed significantly from our own is not supported by uniformitarian principles (explanations of the past based on studies of the present), by evolutionary theory or by archaeological evidence. There are no known populations of Homo sapiens with biologically constrained capacities for behavioral variability. Generations of anthropologists have sought in vain for such primitive people in every corner of the world and have consistently failed to find them. The parsimonious interpretation of this failure is that such humans do not exist.

Nor is there any reason to believe that behaviorally archaic Homo sapiens ever did exist. If there ever were significant numbers of Homo sapiens individuals with cognitive limitations on their capacity for behavioral variability, natural selection by intraspecific competition and predation would have quickly and ruthlessly winnowed them out. In the unforgiving Pleistocene environments in which our species evolved, reproductive isolation was the penalty for stupidity, and lions and wolves were its cure. In other words: No villages, no village idiots. If any such cognitive “winner take all” wipeout event ever happened, it was probably among earlier hominins (Homo ergaster/erectus or Homo heidelbergensis) or during the evolutionary differentiation of our species from these hominin ancestors.

Dividing Homo sapiens into modern and archaic or premodern categories and invoking the evolution of behavioral modernity to explain the difference has never been a good idea. Like the now-discredited scientific concept of race, it reflects hierarchical and typological thinking about human variability that has no place in a truly scientific anthropology. Indeed, the concept of behavioral modernity can be said to be worse than wrong, because it is an obstacle to understanding. Time, energy and research funds that could have been spent investigating the sources of variability in particular behavioral strategies and testing hypotheses about them have been wasted arguing about behavioral modernity.

Anthropology has already faced this error. Writing in the early 20th century, the American ethnologist Franz Boas railed against evolutionary anthropologists who ranked living human societies along an evolutionary scale from primitive to advanced. His arguments found an enthusiastic reception among his colleagues, and they remain basic principles of anthropology to this day. A similar change is needed in the archaeology of human origins. We need to stop looking at artifacts as expressions of evolutionary states and start looking at them as byproducts of behavioral strategies.

2011-03SheaF8.jpgClick to Enlarge ImageThe differences we discover among those strategies will lead us to new and very different kinds of questions than those we have asked thus far. For instance, do similar environmental circumstances elicit different ranges of behavioral variability? Are there differences in the stability of particular behavioral strategies? Are certain strategies uniquely associated with particular hominin species, and if so, why? By focusing on behavioral variability, archaeologists will move toward a more scientific approach to human-origins research. The concept of behavioral modernity, in contrast, gets us nowhere.

Even today, a caveman remains the popular image of what a prehistoric person looked like. This individual usually is shown with enlarged eyebrows, a projecting face, long hair and a beard. The stereotypical caveman is inarticulate and dim-witted, and possesses a limited capacity for innovation. In 2006, GEICO commercials put an ironic twist on this image. Their cavemen were more intelligent, articulate, creative and culturally sophisticated than many “modern” people. In a striking case of life imitating art, recent archaeological discoveries are overturning long-standing misconceptions about early human behavior.

Bibliography

  • Bar-Yosef, O. 2002. The Upper Paleolithic revolution. Annual Review of Anthropology 31:363–393.
  • Clark, G. 1969. World Prehistory: A New Synthesis. Cambridge: Cambridge University Press.
  • Klein, R. G. 2009. The Human Career, third edition. Chicago: University of Chicago Press.
  • Landau, M. L. 1984. Human evolution as narrative. American Scientist 72:262–268.
  • 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., and C. Stringer. 1989. The Human Revolution: Behavioural and Biological Perspectives on the Origins of Modern Humans. Edinburgh: Edinburgh University Press.
  • Nowell, A. 2010. Defining behavioral modernity in the context of Neandertal and anatomically modern human populations. Annual Review of Anthropology 39:437–452.
  • Potts, R. 1998. Variability selection and hominid evolution. Evolutionary Anthropology 7(3):81–96.
  • Shea, J. J. 2008. The Middle Stone Age archaeology of the Lower Omo Valley Kibish Formation: Excavations, lithic assemblages, and inferred patterns of early Homo sapiens behavior. Journal of Human Evolution 55 (3):448–485.
  • Shea, J. J. 2011. Homo sapiens is as Homo sapiens was: Behavioral variability versus “behavioral modernity” in Paleolithic archaeology. Current Anthropology 52(1):1–35.








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