The people who lived in these caves were modern humans who lived by recognizably human methods, hunting game and gathering plant foods. Evidence for our other hominid ancestors--Homo erectus and Homo ergaster, for example--suggests that they primarily scavenged other animal's kills; the Homo sapiens of Klasies River caves knew how to hunt. The Klasies River people dined on shellfish, antelope, seals, penguins, and some unidentified plant foods, roasting them in hearths built for the purpose. The caves were not permanent residences for the humans who inhabited them, as best as we can tell; they only stayed for a few weeks, then moved along to the next hunting stand. Stone tools and flakes made from beach cobbles were recovered from the earliest levels of the site.
Klasies River and Howieson's PoortApart from the debris of living, researchers have also found fragmentary evidence in these earliest levels of the earliest of ritual behavior--cannibalism. Fossil human remains were found in several layers of the Klasies River occupations, fire-blackened fragments of skulls and other bones showing cut marks. While this alone would not convince researchers that cannibalism had taken place, the pieces were mixed with the rubble of kitchen debris--thrown out with the shells and bones of the remainder of the meal. These bones were unequivocally modern human; at a time when no other modern humans are known--only Neanderthals and early modern Homo existed outside of Africa.
By 70,000 years ago, when the layers called by archaeologists Howieson's Poort were laid down, these same caves were used by the descendents with a more sophisticated stone tool technology, backed tools from thin stone blades, and perhaps projectile points. The raw material from these tools came not from the beach, but from rough mines some 20 kilometers away. The Middle Stone Age Howieson's Poort lithic technology is nearly unique for its time; similar tool types are not found anywhere else until the much later Late Stone Age assemblages.
While archaeologists and paleontologists continue to debate whether modern humans are descended only from the Homo sapiens populations from Africa, or from a combination of Homo sapiens and Neanderthal, the Klasies River cave populations are still our ancestors, and are still representatives of the earliest known modern humans on the planet.
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