what a rollercoaster of emotions: "please just have a video- oh they do! great. oh hold on that's a terrible video that shows absolutely nothing and just gives me a headache with its 5 frames per second, why did they even bother?"

I appreciate that you stated it in a way that the fun fact is there's a theory, and not that the theory was definitive fact. But it definitely seems plausible.

Lol, now I'm imagining 200 feet from this cave is the Cave of Initial Sketches.

I wonder if they did a lot of drawings in dirt to get practice.

Yes, this is that one.

I think it also has a lot to do with the humidity of human breath.

I've known about Chauvet cave for years, and I'm still in awe every time I see a picture of it. To think most images in this cave are around 35,000 years old. Human history (written history) is maybe 6,000 years old. This is more than 5 times older than that. Humans existed, and were creating things like this, for 30,000 years before the written word.

Pablo Picasso visited the Lascaux Cave (also in France, but much younger), and said the following:

“We have learned nothing in twelve thousand years.”
― Pablo Picasso

I linked this above, but check out Cave of Forgotten Dreams documentary on this cave.