[Jerusalem Post] Researchers from the University of Cape Town, South Africa, found evidence that contradicts the hypothesis that humans only lived in the region during wetter periods.Researchers found evidence that the dry plateau of Kalahari in South Africa once had abundant sources of water, including streams, pools and waterfalls.
In a peer-reviewed study published in PLOS ONE, researchers conducted data sequencing on samples from deposits of tufa, a porous sedimentary rock made of calcium carbonate that is formed by the evaporation of fresh groundwater as springs.
The researchers, led by Jessica von der Meden, a PhD candidate at the University of Cape Town's (UCT) Department of Geological Sciences and Human Evolution Research Institute, used low-impact sampling in order to preserve the surrounding tufa deposits.
The team used a geological hammer, mallet and chisel to collect 18 of the tufa samples, and then, using a modified drill with a water swivel and a custom diamond-tipped barrel, they collected eleven small cores from the deposits.
The researchers then encased the cores in epoxy and then cut in half with a diamond rock saw and polished before making thin sections to study using a polarizing light microscope.