Resolving the timescale of south-central African palaeoenvironments and their impact on human behaviour and evolution

Timing is everything: accurate dating of the geological record is essential to understand our planet's history, but beyond the limit of radiocarbon dating (~50,000 years) material becomes difficult to date. The Quaternary period (the last ~2.6 million years) provides a rich palaeoenvironmental record vital for testing the usefulness of climate models to predict future climate change. However it is severely underused because of a lack of chronology; recent advances in amino acid dating can overcome this impasse.

Amino acid geochronology uses the time-dependent breakdown of proteins in biominerals (e.g. shells, teeth). Our recent breakthrough has been to isolate entrapped proteins, which behave as a closed system, neither losing products nor gaining reactants over >30 million years. This provides an extremely powerful dating tool for terrestrial deposits. By focusing on a range of different biominerals (molluscs, ostracods, enamel etc.), this PhD will exploit these advances to develop a chronology for southern Africa, a region with a rich but understudied Pleistocene palaeoclimate record and a critical area for a full understanding of human evolution. Stretching beyond the range of the other dating methods available, this will enable the palaeoenvironmental record to be constrained, also allowing us to study the interactions between humans and the changing environment.

Objectives
1) Test biominerals for intra-crystalline protein degradation (IcPD) through high temperature kinetic experiments.
2) Test fossils in deposits of well-constrained age.
3) Develop an IcPD dating framework for southern-central Africa.
4) Using this, develop a regional palaeoenvironmental record for the Pleistocene, providing the context for faunal evolution and behavioural changes in this region.

The project (based in the NERC-recognised amino acid facility at the University of York) will involve multidisciplinary training; the student will gain hands-on expertise in state-of-the-art techniques for analytical method development as well as experience of fieldwork and sampling approaches. The supervisory team combines expertise in geochronology and analytical chemistry (Penkman; York), southern African Palaeolithic archaeology and palaeoenvironments (Barham; Liverpool) & palaeoecological reconstructions using multiple fossil proxies (White, Natural History Museum). Training in techniques will include chromatography, dating methods, palaeoclimate, malacology and Palaeolithic archaeology.