Anthropogeny: The Perspective from Africa

Australopithecus is a genus of hominins whose evolutionary evidence is confined to the African continent. The genus evolved in eastern and/or southern Africa around 4 million years ago, eventually becoming extinct slightly less than two million years ago. Australopithecus is scientifically accepted as the common ancestor of the Paranthropus and Homo. Scientists recognize five species of Australopithecines; Australopithecus anamensis, A. afarensis, A. africanus, A. garhi, and A. sediba. Their relationship to each other and the earliest form of Homo, Homo habilis, remains controversial due to the sparse fossil record in Africa. There are 2 main ways of expressing evolutionary relationships: phylogenetic trees and cladograms. This presentation will explore current fossil evidence regarding members of the genus Australopithecus and their phylogenetic and cladistic relationships.

Early Pleistocene archaeological sites of East Africa have provided us with a wealth of data that is unparalleled anywhere else. The earliest Oldowan and Acheulean industries have been respectively dated to circum 2.6 Ma and 1.75 Ma. The “transition” between the Oldowan and Acheulean technologies and the dynamics that are associated with it are addressed through paleontological and paleoecological studies. At Konso, both Homo erectus and Australopithecus boisei remains are found at the circum 1.4 Ma level, suggesting divergent adaptive strategies of the two species lineages.

The shift from the simple core-flake technology called the Oldowan to the knapping of large flake blanks off from large boulders is evidenced at least at two sites, notably at Konso-Gardula in south Ethiopia and at Kokiselei, west of Lake Turkana, Kenya. At Konso-Gardula, it was demonstrated that the knapping of large flakes from mega-cores and shaping of large cutting tools (LCT) had started by 1.75 Ma and showed important technological changes thereafter. This is seen at various localities until 0.8 Ma, spanning the crudest forms of LCT shaping to the finely made 3D symmetric bifaces.

Acheulean assemblages were recovered from four major time periods at Konso, demonstrating considerable technological changes across time. At 1.75 Ma, the earliest LCTs are represented by large flakes, picks, unifacial handaxes and cleavers; a more typical early Acheulean first occurs at 1.6 Ma and diversifies by circum 1.4 Ma; finally, classical Acheulean assemblages with finely made bifaces emerge by 0.8 Ma. Excavations made in the earlier Konso succession (1.75 – 1.4 Ma) have resulted in the discovery of both Mode I and Mode II assemblages suggesting the coexistence of both technologies at Konso, while, at the same time, development of the Acheulean technology was in full action.

People are interested in knowing their family origins. However, very few people know their family history, and even those who can access genealogical information, usually trace their family history to a few generations. In South Africa, tracing one’s ancestry is even more problematic due to poor family record keeping, the way surnames were given to people who were enslaved, cultural practices of how surnames are transmitted, among other issues. My research on the genetic prehistory of the peoples of sub-Saharan Africa provided many opportunities for engagement with various audiences, including the general public, which led to requests from the public for genetic ancestry testing. Initially there were a few media requests, and then the demands necessitated engagement with my department and the National Health Laboratory Service to provide a service for genetic ancestry testing. The genetic heritage of living people in southern Africa is complex and carries information from the indigenous San and Khoe populations and migrants from other parts of Africa, sea-borne immigrants from Europe dated back to the latter part of the 1600s, slaves from Madagascar, Indonesia and other parts in Africa, indentured laborer’s from India and more recent migrants from around the globe. Genetic markers such as mitochondrial DNA (mtDNA) and Y-chromosome DNA, and more recently whole genome data, have been used to reconstruct the genetic history of populations around the globe.

This presentation will highlight some of the interesting links between the historical and genetic narrative of populations in southern Africa, and address the question asked by many “So, where do we come from?”

Klasies River main site was a favored home base for southern Cape humans between 120 000 and 2300 years ago, leading to the build-up of more than 21 meters of superimposed shell middens. The fossils of early modern humans preserved within the deposits provide a unique glimpse into the appearance of human ancestors from the southern Cape coast and on aspects of their behavior. The extensive midden deposits show that hunter-gatherer-fisher groups visited the site throughout the climatic and environmental fluctuations of the last 120 000 years. They responded dynamically and flexibly to such changes by adapting their subsistence behavior and technologies.  Similar plasticity and complexity are evidenced in their stone tools and the utilization of pigments. The extent of the well-preserved archaeological remains, evidence for the early utilization of marine resources, dynamic responses to changing contexts and cultural ingenuity, bear testament to early human ancestors’ expert abilities to thrive in the Stone Age. The Klasies River archive highlights the achievements of early African populations and the role that they played in the development of humankind.

Coastlines offer rich resources for hunter-gatherers: abundant food, raw materials for making artefacts, possible routes for dispersal and much more. Were coastal areas therefore important in human evolution?  Opinions have gone back and forth over the years. In the second half of the twentieth century, most researchers thought that aquatic resources became important late in prehistory, once populations had grown so that additional sources of food were needed. Today, different perspectives are being offered, with some researchers suggesting that coastal adaptations may have played a role in the emergence of modern humans. Coastal food resources are relatively abundant, but spatially restricted. Did foraging in this landscape promote the high level of social interaction characteristic of our species? Did early modern humans use seafoods only occasionally, or did they focus on them intensively, like many recent coastal populations? One of the difficulties in answering these questions is that coastal sites are rarely well preserved over very long timespans, due to changes in sea level and tectonic activity. The southern African coastline has, however, remained unusually stable over the last several hundred thousand years, with many well-preserved coastal sites. We find more evidence of seafood in recent sites, but is this due to greater consumption or better preservation? From the isotopic composition of archaeological bones and teeth, we can reconstruct aspects of peoples’ diets and how they used the landscape, and infer some features of the way societies were organized. We cannot yet answer all these questions, but we are making progress!