[divbzero]

Yes, and “long enough for us to see them” actually comprises two independent factors: (1) survivorship bias, in that red ochre on rock can last a long time, and (2) “discoverability” bias, in that red ochre on rock is relatively easy to spot.

[throwaway894345]

Additionally perhaps people (would-be discoverers) ignore art in remote places that is not a hand print or otherwise pictographic as probably a natural anomaly and not human-made?