There were even “cave galleries” where only respected artists would be allowed to paint on the wall. Like the Chauvet Cave in France. https://en.m.wikipedia.org/wiki/Chauvet_Cave
Some really advanced techniques were used to create these drawings too, for example using the unique shape of the walls to create interesting effects of perspective.
Researchers couldn’t figure out why many of the animals seemed to have more then 4 legs, some with 6 or 7. It was then suggested that if viewed by a flickering firelight it would create a visual illusion of movement
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