The work is at least 30,000 years older than the earliest previously known abstract and figurative drawings. What is a symbol ... Tribology is the science of friction and wear.

Scientists use symbols to represent the different components in a circuit. Symbols are simplified drawings. We use symbols because they are easier to draw and they act as a universal language ...

Blombos Cave drawing with ochre pencil on silcrete stone ... But trying to understand what the ancient symbols meant may be an inscrutable puzzle. “There, I think we’re stumped,” Henshilwood ...

Homo sapiens created the world's first known drawing on this stone about 73,000 ... and Life's Little Mysteries editor at Live Science. She also reports on general science, including paleontology.