From an article in New Scientist titled “The writing on the cave wall”, this infographic shows that many symbols and figures used in cave-wall paintings have similar forms.
What emerged was startling: 26 signs, all drawn in the same style, appeared again and again at numerous sites (see illustration). Admittedly, some of the symbols are pretty basic, like straight lines, circles and triangles, but the fact that many of the more complex designs also appeared in several places hinted to von Petzinger and Nowell that they were meaningful - perhaps even the seeds of written communication.
A group of 26 symbols crops up at Stone Age sites throughout the world – are these the origin of the written word?
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