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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

An Idea Is Born

2011-03SheaF2.jpgClick to Enlarge ImageArchaeology’s concept of archaic versus modern humans developed as prehistoric archaeological research spread from Europe to other regions. The study of prehistoric people began in Europe during the 19th century in scientific societies, museums and universities. By the 1920s, discoveries made at a number of European archaeological sites had prompted a consensus about the Paleolithic Period, which is now dated from 12,000 to nearly 2.6 million years ago. Archaeologists divided this period into Lower (oldest), Middle, and Upper (youngest) Paleolithic phases. Distinctive stone-tool assemblages—or “industries”—characterized each phase. Archaeologists identified these industries by the presence of diagnostic artifact types, such as Acheulian hand axes (Lower Paleolithic), Mousterian scrapers made on Levallois flakes (Middle Paleolithic), and Aurignacian prismatic blades and carved antler points (Upper Paleolithic). The fact that tools from more recent industries were lighter, smaller and more heavily modified suggested there was a trend toward greater technological and cultural sophistication in the Paleolithic sequence. European Upper Paleolithic industries were associated exclusively with Homo sapiens fossils and Lower and Middle Paleolithic industries were associated with earlier hominins (Homo heidelbergensis and Homo neanderthalensis). This supported the idea that there were important evolutionary differences between modern Homo sapiens and earlier archaic hominins.

Early Upper Paleolithic contexts in Europe preserve evidence for prismatic blade production, carved bone tools, projectile weaponry, complex hearths, personal adornments, art, long-distance trade, mortuary rituals, architecture, food storage and specialized big-game hunting, as well as systematic exploitation of smaller prey and aquatic resources. Furthermore, the variability of these behaviors within the Upper Paleolithic is much greater than that seen in earlier periods. In much the same way that anthropologists have documented cultural variability among recent humans, archaeologists can easily tell whether a particular carved bone point or bone bead is from a site in Spain, France or Germany. Not surprisingly, most prehistorians accept that the archaeology of the Upper Paleolithic is, in effect, “the archaeology of us.”

Lower and Middle Paleolithic stone tools and other artifacts found in Europe and elsewhere vary within a narrow range of simple forms. Properly equipped and motivated modern-day flintknappers (people who make stone tools) can turn out replicas of any of these tools in minutes, if not seconds. Many of the differences among Lower and Middle Paleolithic artifacts simply reflect variation in rock types and the extent to which tools were resharpened. Geographic and chronological differences among Middle and Lower Paleolithic tools mostly involve differences in relative frequencies of these simple tool types. Nearly the same range of Lower and Middle Paleolithic stone tool types are found throughout much of Europe, Africa and Asia.

The differences between the Lower/Middle and Upper Paleolithic records in Europe are so pronounced that from the 1970s onward prehistorians have described the transition between them as “The Upper Paleolithic Revolution.” This regional phenomenon went global in the late 1980s after a conference at Cambridge University entitled “The Human Revolution.” This revolution was portrayed as a watershed event that set recent modern humans apart from their archaic predecessors and from other hominins, such as Homo neanderthalensis. The causes of this assumed transformation were hotly debated. Scientists such as Richard Klein attributed the changes to the FOXP2 polymorphism, the so-called language gene. But the polymorphism was eventually discovered in Neanderthal DNA too. Many researchers—such as Christopher Henshilwood of the University of Witwatersrand, Curtis Marean of Arizona State University, Paul Mellars of the University of Cambridge, April Nowell of the University of Victoria and Phil Chase of the University of Pennsylvania—continue to see symbolic behavior as a crucial component of behavioral modernity. Yet as João Zilhão of the University of Bristol and Francesco d’Errico of the University of Bordeaux have argued, finds of mineral pigments, perforated beads, burials and artifact-style variation associated with Neanderthals challenge the hypothesis that symbol use, or anything else for that matter, was responsible for a quality of behavioral modernity unique to Homo sapiens.




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