Introduction

[PK: to do: search #expansion and #article: evolution of vai: bilerian]
For over a century, psychologists have designed experiments in which participants are required to draw and reproduce a series of graphic images [footnote Philippe 1897; PK perhaps also Balfour 1893: The evolution of decorative art]. In the simplest versions of these tasks an individual draws a picture to be copied by a second individual, and this output becomes the input for a third, and so on. The first to examine the theoretical implications of such semiotic transmission experiments was F. C. Bartlett who developed simple pencil-and-paper tasks to test the dynamics of human memory \cite{RN1844}. Noticing that the figurative images tended to become simpler and more conventionalised over successive "generations", Bartlett perceived a real-world parallel in the historical evolution of writing systems whereby "realistic pictures" eventually became "non-representational conventional signs" (p95). So taken was he by this observed correspondence that he was inspired to use Native American (p97) pictograms and Egyptian hieroglyphics (p180) as the primary input for a number of his tasks. As the field of experimental semiotics began to develop, such graphic communication tasks became much more sophisticated but scholars continued to suppose that the bias towards abstraction must have relevance to the history of writing systems. In a recent example, Simon Garrod et al \cite{Garrod_2007} developed Pictionary-style graphic tasks that detected a transition towards non-iconic simplicity (Figure 1) leading them to speculate that similar processes must have underpinned the loss of iconicity in the cuneiform and Chinese writing systems over deep time-scales (Figure 2).