The Southern African Stone Age covers the longest period in human history, that is, the last three million years of human evolution and adaptation in a region south of the 18th parallel south. The region includes the countries of Botswana, Lesotho, Mozambique, Namibia, South Africa, Swaziland, and Zimbabwe, with a northern border marked by the Kunene River between Angola and Namibia, the Cuando River on the borders of Angola, Namibia, and Botswana, and the Zambezi River. It is divided into three main phases, known as Early, Middle, and Later Stone Age. The Early Stone Age had its beginning about three million years ago with the development of Australopithecus, found in South Africa in the region called the Cradle of Humankind. The earliest stone tools in the region were discovered in the cave of Sterkfontein and are dated to around two million years ago. These first stone tools, which include choppers, polyhedrons, and subspheroids, among other artifacts, are part of an industrial complex known as the Oldowan, which lasted for a few hundred thousand of years. It was followed by the Acheulean, known by its unique large cutting tools, the handaxes, cleavers, and picks, starting about 1.8 million years ago. During this period, species such as Homo habilis and Homo erectus/ergaster walked over southern Africa. The Middle Stone Age, starting about three hundred thousand years ago, seems to be directly associated with the emergence of a new species, Homo sapiens. This phase shows a wide cultural diversity in the region, and in fact across the whole African continent, both in time and space. This is a phase drastically marked by technological and cultural innovations, such as the use of bow and arrow, hafting, bone tools, lithic heat treatment, use of pigments, production of body ornaments such as beads, art in the form of engravings, and, finally, the systematic inclusion of shellfish and plants in the human diet. These innovations, however, were not used all in the same location. This congregation of techniques and innovations took place only during the next phase, the Later Stone Age, which started around thirty-five thousand years ago. It is likely the result of an important demographic change that occurred as a response to climatic oscillations that took place at the world level. Like the Middle Stone Age, the Later Stone Age saw an incredible range of cultural diversity in the large region of southern Africa. Traditionally, it was believed that the main differences between the Middle and Later Stone Ages were based on a dichotomy where, on one side, points and flake industries resulting from prepared cores such as Levallois were present, and on the other, simple cores producing microlithic assemblages, sometimes geometric, together with art, and beads and organic tools were present. Today, however, that simplistic contrast is known to be wrong, and the differences in cultural complexity are more a matter of concentration than innovation. The Later Stone Age hunter-gatherers were finally slowly replaced by farmers and herders and later by Iron Age populations, between twenty-five hundred years ago and the recent historical present.