TAKE a forked stick and plant one of the prongs in sand. Turn it like a compass and you will etch a perfect circle, as demonstrated (above) on a South African beach by Charles Helm of the African Centre for Coastal Palaeoscience in Gqeberha.
It is a natural human impulse to draw in the sand, and it seems our ancestors were feeling the same drive at least 136,000 years ago. In 2018, Helm discovered a perfect circle with a central depression on a slab of sandstone (pictured above) in the Garden Route National Park. This area is known for traces of early Homo sapiens, including rock art and the oldest footprint found (pictured below), which dates back about 150,000 years.
The slab was once the surface of a coastal sand flat that has since solidified into rock. Helm has discovered other patterns in the same outcrop that could have been made by people, including grooves, cross-hatches, parallel lines and a perfect triangle (pictured below). The coloured images represent the depth of the impressions.
Helm ruled out natural causes such as wind, water, non-human animals or vegetation, and was left with one possibility – they were made intentionally by people, though they probably didn’t mean much. “I like to think it’s kids playing around,” says Helm.
He says these sand drawings should be classed as a fifth type of palaeoart, after cave paintings (pictographs), rock engravings (petroglyphs), images carved on trees (dendroglyphs) and arrangements of rocks or earth (geoglyphs). The name he proposes is ammoglyphs, after ammos, the Greek word for sand.