Arid regions of South Africa were once home to ancient lakes

Written on 05/20/2023
Mark Milligan


Recently discovered evidence supporting the existence of ancient lakes in remarkably dry areas of South Africa indicates that Stone Age humans may have inhabited a more extensive range across the continent than initially believed.

A study led by the University of Leicester proposes that conducting further archaeological investigations in the inland regions of South Africa, a nation known for its exceptionally significant archaeological heritage, could unveil additional insights into the behaviours and migrations of our ancient predecessors.

Considerable efforts have been devoted to investigating the Stone Age archaeological evidence in South Africa, particularly within the last 150,000 years. The emphasis has mainly been on studying the extraordinary records found in coastal caves and rock shelters. However, our knowledge of human habitation and the resources accessible in the vast inland areas of the country has remained largely unknown until recently.

A recent study conducted by a multinational team of researchers from South Africa, the United Kingdom, the United States, and France has unveiled compelling evidence indicating the existence of several large bodies of water in the presently arid interior of South Africa during the last Ice Age.

Specifically, these water bodies were sustained approximately 50,000-40,000 years ago and again 31,000 years ago. The researchers were able to accurately estimate the volume of water required to fill these ancient lakes, enabling them to reconstruct the climatic changes necessary for their formation and the subsequent impact on the region's hydrology, flora, and fauna.

Their findings paint a picture of a diverse and fertile region that would have been capable of supporting hunter-gatherer communities of the time.

Team member Dr Andrew Carr from the University of Leicester School of Geography, Geology and the Environment said: “This is currently the best evidence for when these lakes existed. This region has been something of a gap on the map, climatically and archaeologically. We know humans were present at times during the last ice age, as archaeological materials are scattered across the landscape surface. This new work hints at when and why humans used this landscape.

“These areas look inhospitable today but were seemingly much less so at times in the past, and this has implications for when and how groups of people used the landscape and potentially how they were connected and exchanged ideas.

“It also tells us something about the sensitivity of ecosystems and environments to global climatic change. You can see how these desert landscapes can respond in quite significant ways to global climate changes and understand how the human species responded and how adaptable it would have been.”

The team of scientists conducted an investigation of three lakes located in the arid western interior of South Africa, extending eastward to Kimberley.

By utilising computer models of regional hydrology, they discovered that the environmental conditions required for the formation of these studied lakes would have resulted in significant alterations to the numerous rivers and lakes in the region, which are presently ephemeral, as the water table rose.

Dr Carr added: “The next step is to start to look for sites where we can do more direct dating of the occurrence of stone tools in this region. The work shows that at times the region offered a range of resources, and the archaeological ‘gap on the map’ is much more likely to reflect the lack of sites preserving deep archaeological deposits.

“The region is quite challenging for archaeology as most materials lie in the open on the desert surface with no stratigraphic context - hence it's very difficult to know how long it's been there.”

UNIVERSITY OF LEICESTER