I am standing on a dune looking out to sea. It’s 2024, but I’m thinking about a very different time. Hundreds of thousands of years ago this 350km stretch of southern African coast looked very different. It was home to giant zebra, bird species that are now extinct, giant tortoises and crocodiles. Our hominin ancestors roamed the area.
We know some of these facts because of body fossils. But South Africa’s Cape south coast is also home to another rich source of information, which our research team from the African Centre for Coastal Palaeoscience at Nelson Mandela University has documented over the past 15 years: fossilised tracksites. These trace fossils date to the Pleistocene epoch, with ages ranging from 400,000 years to 35,000 years. Most of them are preserved in a rock type known as aeolianite (cemented dune surfaces).
The tracksites are an example of what’s known as geoheritage, which the Geological Society of South Africa calls a “descriptive term applied to sites (geosites) or areas of geologic features with significant scientific, educational, cultural, or aesthetic value”. The importance of geoheritage is becoming increasingly recognised at a global level; for example, it is relevant to the United Nations’ 2030 Agenda Sustainable Development goals, and Unesco’s Global Geoparks “celebrate the links between geological heritage and all other types of heritage”.
