(CNN) – Scientists have found the oldest known drawing in history — and it looks #familiar.
The 73,000-year-old red cross-hatch pattern looks just like a hashtag, also recognizable as the US pound sign, the number sign or the hash symbol. The six-by-three-line pattern was drawn on a flake of silicrete, which forms when sand and gravel cement together.
The discovery could change how researchers perceive early humans, because the drawing predates other art found in Africa, Europe and Southeast Asia by 30,000 years.
The flake was found in Blombos Cave, east of Cape Town on the southern coast of South Africa. This cave is a well-known site for archaeologists where some of the oldest evidence for early human activity has included artifacts between 70,000 and 100,000 years old, including shell beads and stone tools. Excavations began at the cave in 1991 and are ongoing.
Details of the flake and its design were published Wednesday in the journal Nature. The researchers ran microscopic and chemical analyses of the flake and its design.
The red color of the drawing is actually ocher. Engraved, cross-hatched pieces of ocher have also been found in the cave. The flake itself is smooth and was probably part of a grindstone before it was used for this purpose.
Though it resembles a hashtag, the researchers say the abrupt halt of the lines on the flake’s edge suggest that the pattern was part of something on a larger surface. The original drawing may have been more complex, as well.
It was discovered in 2011. Researchers carefully washed the flake with water when it was found and didn’t realize the design on it until afterward.
The researchers later attempted to re-create the drawing in various ways and determined that an ocher crayon bearing a 1- to 3-millimeter pointed tip was used. Some of the lines were made with a single stroke of the crayon, while other, more defined lines are due to multiple strokes. Some lines even suggest that the object was turned while the drawing was being done.
Although there are older findings of art, they mainly include engravings on shell, bone, ocher, eggshells and bedrock, as well as ocher markings in caves. But examples of drawing techniques, especially abstract and figurative drawing, are much younger.
Drawings suggest insight into the culture, behavior and cognition of early humans. This drawing shows that early Homo sapiens in southern Africa were able to create designs using different techniques on varied surfaces, according to the study. It also suggests that there may be more drawings and paintings from this time period to be found.