I came across this cool infographic yesterday on Twitter, which is taken from a New Scientist article from 2010. Click to go through to the detailed image:
French caves are known for their prehistoric rock art. But also marked on the walls around the paintings are 26 symbols that have appeared again and again at French sites across 25,000 years of prehistory. Early signs suggest that many of these symbols crop up in other parts of the world too, leading some to wonder if symbolic communication arose with early humans.
Funnily enough, the next thing I clicked on was a link to the new trailer for Ridley Scott's Prometheus, which features a plotline in which common symbols are found in prehistoric cultures around the world (an "invitation" from an alien race). I thought I'd include it below, simply for your own enjoyment of my fun little synchronicity.
At least if we decode some ancient pictograms in future from an alien race, we'll be more circumspect about accepting the invitation...