structural:expansion
Cognitive archaeology

Artisans living in the MSA must have been able to think in abstract terms about properties of plant gums and natural iron products, even though they lacked empirical means for gauging them. Qualities of gum, such as wet, sticky, and viscous, were mentally abstracted, and these meanings counterpoised against ochre properties, such as dry, loose, and dehydrating. Simultaneously, the artisan had to think about the correct position for placing stone inserts on the shafts.... Although fully modern behaviour is recognisable relatively late in the MSA, the circumstantial evidence provided here implies that people who made compound adhesives in the MSA shared at least some advanced behaviours with their modern successors.