NEW YORK — It looks a bit like a hashtag, but it’s 73,000 years old. And scientists say this tiny sketch found in a South African cave is the oldest known drawing. It’s not the earliest deliberate ...

Archaeologists who excavated a seaside cave in South Africa have discovered what they say is the world's oldest drawing. It is an abstract pattern, a crosshatch of red lines, like a hashtag, on a rock ...

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American Hashtags have become a standard in ...