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Author: Natasha Joseph, Commissioning Editor
Original article: https://theconversation.com/fossil-tracks-paint-a-picture-of-south-africas-ancient-coastal-landscape-five-essential-reads-244680
Fossils may look to the untrained eye like an unremarkable set of sandy bones. But those bones can deepen or even rewrite our understanding of ancient history – and South Africa is a fossil treasure trove. Some of the country’s “treasures” have changed our own species’ family tree. These include the 1924 discovery of a juvenile skull dubbed the Taung Child and ascribed to a new hominin species called Australopithecus africanus, and the announcement in 2015 of a previously unknown hominin species, Homo naledi. Researchers have also learned a tremendous amount about the plants, animals and insects that populated ancient landscapes in what is today South Africa.
Then there’s ichnology: the study of ancient tracks and traces. The steps our human ancestors took; the paths forged by long-extinct elephant species; the patterns made on ancient dune surfaces – many of these are preserved today in those surfaces, known as aeolianites. South Africa’s Cape south coast has emerged as a global hotspot for all kinds of fossil tracks and traces.
Charles Helm, Jan Carlo De Vynck, Alan Whitfield and Hayley Cawthra are among those researching a 350km stretch of the country’s south coast who have, over the past 15 years, identified more than 350 vertebrate tracks. These date back anywhere from tens of thousands to hundreds of thousands of years ago. Here are just a few of the articles they’ve written for The Conversation Africa outlining their discoveries.
Where our ancestors walked
If you’ve ever laced up your sneakers for a walk on the beach (or forgone them entirely because you prefer to feel the sand under your feet), you may be following in our hominin ancestors’ footsteps.
Read more:
Fossil finds: footprints on South Africa’s coast offer a glimpse into our ancestors’ lives
Some on the Cape south coast strolled, some jogged – and some even wore what may be the oldest footwear ever donned by humans.
Read more:
Ancient shoes: tracks on a South African beach offer oldest evidence yet of human footwear
The art of the matter
Our ancestors left their mark on the landscape in other ways, too.
For instance, they created scratch circles. These structures are formed when the end of a tethered object is passively rotated into the surrounding sediment, such as when a blade of grass that’s rooted to the ground blows in the wind, so that its loose end inscribes a perfect circle or arc. The same effect can be achieved with a forked stick and a little patience. The researchers suggest this may be precisely what some hominins did on the Cape south coast – and that those markings may amount to some of the earliest examples of really ancient, early forms of art.
Read more:
Fossilised circles in the sand on South Africa’s coast may be artwork by our early ancestors
Ancient humans may also have been experimenting with different mediums. Take the unusually symmetrical rock, shaped uncannily like a stingray without a tail, discovered along the coast in 2018. The researchers believe it represents a sand-sculpture of a blue stingray (Dasyatis chrysonata) and that it may have begun with tracing a specimen in the sand.
Slithering and stamping
Of course, our ancestors were not alone in this landscape. They shared it with many creatures, large and small. One of the more dangerous inhabitants was what researchers are certain was a puff adder (Bitis arietans), a specimen of which left its indelible, slithering mark somewhere between 93,000 and 83,000 years ago.
Read more:
Fossil snake traces: another world-first find on South Africa’s Cape south coast
On the other end of the size spectrum, researchers have discovered the tracks of the giant Cape zebra, a species that went extinct 10,000 years ago.
Read more:
New discovery: fossilised giant zebra tracks found in South Africa