It must of been aliens.

“Anthropomorphic,” the figures of men with exaggerated torsos and strange headdresses.  Two teenage girls were viewing petroglyphs, similar to these.  One turned to the other and said, “It must have been aliens.”  Although the experts can mostly guess at the meaning of petroglyphs, aliens seem unlikely.  I wonder what meaning people attribute to our art generations from  now in the absence of a written record.  From petroglyphs, to cliff dwellings, to sandy riverside beaches and towering dunes, the sandstone of the western United States creates a land of wonders.