Modern-day surface and heat treatment specialists might be interested or, indeed, bemused to learn that their particular branch of engineering had its roots in Africa, possibly more than a hundred thousand years ago. A group of international researchers working at a cave site in South Africa has unearthed evidence of early human engineering endeavour in which people were heat-treating stone to make it easier to fashion into tools and weapons at least 70,000 years ago and possibly as early as 164,000 years ago.
The team, led by Professor Curtis Marean of Arizona State University (ASU) claims that the ‘technology’ required a novel association between fire, its heat and a structural change in stone that made it easier to work. The findings, according to an ASU spokesperson, conjure up the notion of “complex cognition in these early engineers”. Hitherto, it was thought that primitive forms of heat treatment emerged in Europe much later than these findings.
Kyle Brown, a team member from the University of Cape Town and a lead author of the paper, had been trying to recreate the silcrete tools the team had discovered, but was unable to get quite the same result. He concluded that early humans living in what is now Pinnacle Point on the southern tip of the continent, were using controlled hearths in a complex process to heat the silcrete (a silica-rich rock similar to flint) and change its properties.
Indeed, further experiments revealed that it took 20 to 40kg of hardwood and almost 30 hours to create the temperature needed to promote the flaky surface structure that enabled the silcrete to be worked into fine blades.
According to Professor Marean, this expression of cognitive complexity in technology by these early modern humans on the south coast of South Africa provides further evidence that this locality may have been the origin location for the lineage that leads to all humans. There is no consensus as to when modern human behaviour appears, but by 70,000 years ago there is good evidence for symbolic behaviour.
“Many researchers are looking for technological proxies for complex cognition,” says Professor Marean. “Heat treatment is likely one such proxy.”
Silly season survey
Meanwhile, back in the 21st century there are other, less momentous, issues to exercise our minds. According to research released last week by Kwik-Fit, some 6.7 million (20%) British motorists had a heated row with their partner while driving in the last 12 months. And with 8% of motorists claiming a warm car interior as the catalyst for such arguments, Kwik-Fit fears the overall number could rise further as the country experiences peak seasonal temperatures.
Notwithstanding the fact that Kwik-Fit has some interest in re-charging automotive air conditioning systems, there is a serious point in all this. According to the ubiquitous car repair operator, motorists should take note: it is not just their relationships at risk from bickering, as 2% of all road accidents are caused by in-car distractions.
There is nothing new in all this, of course. Disagreements over driving technique (43%), choice of music or radio station (11%), and grumbles over traffic jams (10%) are perennial gripes. And while, many clashes are inevitable, others are easily avoided, say the researchers. Not surprisingly, a fully charged air conditioning system is one preventative measure that comes high up on the recommendation list.
Perhaps those motorists of greener hue will hesitate when it comes to pressing the ‘A/C’ button and just open their windows. Better still, leave the car parked at home, if the option presents itself, and instead swelter on a bus or train. It’s pretty likely the air conditioning (if it exists at all) will not be working, but at least someone else is in the driving seat.
Les Hunt
Editor