BOSTON--Humans living in the eastern Mediterranean first began wearing beads just when their populations apparently began to expand. The finding, reported here today at the annual meeting of the American Association for the Advancement of Science, publisher of ScienceNOW, suggests to the researcher that modern behaviors such as dolling up with jewelry may have originated from a need to communicate rather than a fundamental change in the human brain.
Humans started wearing beads around 42,000 years ago, according to archaeological sites in Bulgaria and Kenya. New excavations have now uncovered evidence of a third independent invention of ornamental beads. Pierced seashells start to appear in Turkey and Lebanon between 41,000 and 43,000 years ago, reported Mary Stiner of the University of Arizona in Tucson. At the same time, Stiner and her colleagues found, the locals started eating fewer tortoises and mollusks and more hares, as evidenced by the bones found at human settlements. To Stiner, the fact that hunters were forced to seek swifter quarry implies that the human population was growing. (The tortoise may have won one highly publicized contest, but the hare won the race to escape the hungry caveman.)
This population growth may have prodded an explosion of bead use as a means of more efficient communication, Stiner says. Although other scholars suggest that ornamentation and other "modern" use of symbols was prompted by a so-called cognitive revolution in brain wiring, decorations may be a response to more frequent social encounters and the need to convey more information about oneself to strangers. "Rather than saying it's a new brand of human being, we're saying it's a new rate of social contact," she says. Furthermore, a sudden biological change most likely would have occurred in only one place, Stiner says, whereas ornamentation arose independently in at least three.
The theory is plausible and intriguing, says Frank Hole, an archaeologist from Yale University, but he notes that the finding is only a correlation. "There are other cases where people are living close together and not doing anything like this," he says.