The oldest Homo sapiens remains discovered to date were recovered from the Bouri site, in Ethiopia, in strata dated to ~160,000 years ago. But, as far as we have been able to recognize, the general physical build of Homo sapiens didn't carry with it any of the cultural, social, and behavioral characteristics we have today.
The point at which human beings became human beings—-that is to say, the point at which the physical frame of Homo sapiens was accompanied by modern behaviors—-was traditionally pegged as the end of the Middle Paleolithic and the beginning of the Upper Paleolithic, about 45,000 years ago. But research over the last twenty years has shown that the transition to what archaeologists and paleoanthropologists call "behavioral modernity" was not a point in time, but rather a process extending over many tens of thousands of years.
One of the key pieces of evidence for that transition to modernity is shell beads. Perforated shell beads have been identified at Middle Stone Age sites in Africa and the near east, dated to between 70,000 and 130,000 ago. Those discoveries are part of the growing evidence that human behavioral modernity is much older than what was formerly believed.
This photo essay of shell beads recovered from ancient Homo sapiens sites addresses some of the issues of behavioral modernity, and what it means to be human.
Sources and Further Information
Bouzouggar, A., et al. 2007 82,000-year-old shell beads from North Africa and implications for the origins of modern human behavior. Proceedings of the National Academy of Sciences 104(24):9964-9969.
Vanhaeren, Marian, et al. 2006 Middle Paleolithic Shell Beads in Israel and Algeria. Science 312:1785-1788.