|Six ways in which segments can be rotated for use as|
tools and weapons. The stippled areas represent adhesive.
It was thought until recently that man began use of the handle to extend the power and reach of his arm 30,000 years ago. I was astounded to learn that the handle was such a recent invention, and in response to a request for more current information, Mary Marzke at the University of Arizona sent me links to an article by Lyn Wadley on the use of adhesives to attach stone to wood in the making of shafted tools, weapons and instruments.
Wadley's work was published in Current Anthropology, and illustrates the intellect and environmental acuity involved as early man crafted tools to enable his survival. Evidently, there was enough adhesive remaining on some crafted pieces of stone from 70,000 years ago to analyze reformulate the means through which they were attached. This work pushes forward by 40,000 years, the earlier speculation by V.G. Childe and others that the handle came as late as 30,000 years ago.
Compound adhesives were made in southern Africa at least 70,000 years ago, where they were used to attach similarly shaped stone segments to hafts. Mental rotation, a capacity implying advanced working‐memory capacity, was required to place the segments in various positions to create novel weapons and tools. The compound glues used to fix the segments to shafts are made from disparate ingredients, using an irreversible process. The steps required for compound‐adhesive manufacture demonstrate multitasking and the use of abstraction and recursion. As is the case in recursive language, the artisan needed to hold in mind what was previously done in order to carry out what was still needed. Cognitive fluidity enabled people to do and think several things at the same time, for example, mix glue from disparate ingredients, mentally rotate segments, talk, and maintain fire temperature. Thus, there is a case for attributing advanced mental abilities to people who lived 70,000 years ago in Africa without necessarily invoking symbolic behavior.There is no concrete evidence that man's development came as a result of language alone, but there is evidence that the making of things took a leading role in the development of man. There is a growing body of evidence that making the tools for our survival and the increased size of the human frontal lobe were parallel developments. You can find Lyn Wadley's article Compound‐Adhesive Manufacture as a Behavioral Proxy for Complex Cognition in the Middle Stone Age here. In order to understand all this and write this paper, Wadley had to make the adhesive from materials found in the natural environment and then replicate the methods for attachment, demonstrating again that you won't really learn all that much about real things by just yakking. "Her main research interest is ancient cognition and her experimental archaeology is geared towards understanding the mental architecture required for various behaviors."
Over the weekend, A+ Fellows went through a dance routine requiring physical rotation described on what the teacher called a "magic square." The exercise was a means of applying spatial sense in problem solving, very much like the process used in making the adhesive as described above.
In order to better understand your own mental architecture,
Make, fix, create, thus extending your reach that others may learn likewise.