If we look at the relatively detailed archaeological record of the last 100 000 years, there is good evidence for substantial population expansion and contraction. It is difficult to know what sparked these processes, but we can reconstruct some aspects of the far-reaching changes that occurred in hunter-gatherer societies. Can we then use these insights to try to understand what happened many tens of thousands of years earlier, in the Middle Stone Age? Archaeologists have divergent ideas about this period. Judy Sealy will examine some of the conflicting interpretations of research on Still Bay, Howieson's Poort and the emergence of modern humans in the light of archaeological evidence from more recent times.

Judith Sealy is Professor and Head of the Department of Archaeology at the University of Cape Town and also holds overall academic responsibility for the Stable Light Isotope laboratory. She obtained her undergraduate and postgraduate degrees at UCT, helping to develop chemical analytical approaches now widely used in archaeology. Her research focuses on hunter-gatherer communities on the Cape coast, especially the reconstruction of the diets and environments of ancient societies. Her work specifically aims to combine different approaches (usually separated into different subfields of archaeology) into a more holistic picture of the past. She is a Fellow of the Royal Society of South Africa and of the University of Cape Town. Judy currently serves on the editorial boards of the Journal of Archaeological Science, Azania and Southern African Humanities, and is a former Editor of the South African Archaeological Bulletin and Associate Editor of Archaeometry. She is President of the South African Archaeological Society.