Long before humans painted caves or made colorful necklaces out of snail shells, they manufactured beautifully symmetrical, teardrop-shaped stone tools that archaeologists call hand axes, such as the ones shown at left from Atapuerca, Spain. At least, hand axes seem beautiful to us today, even if their exact function and meaning are a matter of debate. Most archaeologists think that hand axes, which begin showing up at archaeological sites about 1.7 million years ago, were used to cut plants and butcher animals. And many assume that making such a symmetrical object required a mental template and the ability to impose a predetermined form on a piece of stone. As I discuss in this month’s Origins essay in Science, these talents could be considered proxies for symbolic capacities. And some researchers—as I discuss in a Random Sample in this week’s issue of Science—have suggested that hand axes were also the result of Darwinian “sexual selection.” According to this controversial idea, a well-made hand ax was a sign that its maker, presumed to be a guy, had good genes and would be a suitable mate for any gal lucky enough to have him.
So hand axes have been considered to be handy tools, courting devices, and signs of symbolic smarts. But what if they were none of these things? Since the early 1990s, one archaeologist has argued that there is no evidence early humans actually intended to make hand axes. Iain Davidson, now a professor emeritus at the University of New England (UNE) in Armidale, Australia, contends that the hand ax might have been what was left over when toolmakers were done striking sharp flakes from a stone core.
Davidson first argued for what he calls the finished-artifact fallacy in 1993, together with UNE psychologist William Noble, and he has elaborated on the idea in more recent publications. I caught up with him late last year at Harvard University, where he is currently a visiting professor. Over a long and pleasant lunch in Harvard Square, he made it clear that he has not changed his mind on the issue.
For one thing, Davidson says, archaeologists tend to focus their studies on the most symmetrical hand axes, thus introducing a bias into their analyses. They see more patterning than really exists on average and then interpret that patterning as evidence that early humans intended to create tools that look that way. And because hand axes were probably made by striking flakes from a core with a second stone—indeed, the marks where the flakes were taken off are clearly visible on the hand ax—archaeologists are making unproven assumptions when they conclude that the hand ax rather than the flakes were the most important product, Davidson contends. At the 500,000-year-old site of Boxgrove in England, for example, where hundreds of hand axes have been found, there are also signs that the flakes taken from them were used as tools by early humans.
“I can imagine a situation at Boxgrove where [early humans] were walking around with a core, striking off flakes when they needed them, and then abandoning the core when it was no longer useful,” Davidson told me. As for why the core would have that characteristic teardrop shape, Davidson explained that it would be easier to hold in the hand if you only took flakes off of one end.
Davidson’s view is definitely a minority one. “The form of [hand axes] clearly reflects the intention of the toolmakers,” says archaeologist Dietrich Stout of University College London. But few archaeologists argue that the flakes could not also have been used as tools, and Davidson’s idea does appeal to some. Anthropologist April Nowell of the University of Victoria in Canada, who challenges the sexual-selection hypothesis, told me that she is “sympathetic” to Davidson’s notion. “People get hung up on the symmetrical form that some [hand axes] have,” Nowell said. “We have exaggerated what a typical hand ax looks like, and we don’t think about the less refined ones. There is a variation from tools that just look like cores to those that look like hand axes.”
PHOTO CREDIT: José-Manuel Benito Álvarez