Local historian Big Old Goofy World tells us all about it:
This mural on the side of the Bernal Heights library is a remake of an older more elaborate one, from a time when Black-Brown unity was the big issue in the neighborhood. The original also featured a Mayan pyramid next to an Egyptian pyramid — all beneath the Transamerica Pyramid.
Lol ancient black folk + ancient brown folk + …contemporary investment bankers???
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Well, nothing is funny about black and brown unity.