|Six ways in which segments can be rotated for use as|
tools and weapons. The stippled areas represent adhesive.
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."
In order to better understand your own mental architecture,
Make, fix and create...