Our research uses DNA sequence analysis to answer archaeological questions. The projects involve analysis of both modern and preserved specimens, the latter studied by ancient DNA techniques, many of which have been developed at Manchester.
ADAPT – Life in a cold climate: the adaptation of cereals to new environments and the establishment of agriculture in Europe
This ERC project explores the concept of agricultural spread as analogous to enforced climate change and asks how cereals adapted to the new environments to which they were exposed when agriculture was introduced into Europe during the period 7000–4000 BC. The study material is a large collection of barley and wheat landraces (historic varieties) collected from different parts of Europe. The project combines genome sequencing and transcriptome profiling with ecological niche modelling to identify regions of Europe where early crops underwent evolutionary adaptation in response to local environmental conditions. We then compare these data with archaeological information, in order to understand whether pauses in the advance of agriculture were caused by the need for crops to undergo genetic adaptation to the new environments into which they were being taken, and whether further genetic adaptation was needed before crops became productive enough to support long term population growth. As well as providing a new dimension to our understanding of early European agriculture, the project also informs work on the impact that future environmental change could have on the sustainability of modern cereal cultivation.
EOA – Evolutionary origins of agriculture
We are partners in a second ERC project with the University of Sheffield. The overall aim is to improve understanding of the selective pressures acting on early crop domestication in Western Asia, combining elements of experimental plant ecology, molecular biology, archaeobotany and GIS analysis. In the Manchester part of the project we are using computer simulations to determine if the patterns of genetic diversity seen in landraces can reveal the order in which individual traits were selected by early farmers. In particular, we are investigating if the increase in seed size that accompanied domestication was to due to direct selection for this trait, or resulted from farmers selecting plants with a more vigorous growth habit.
Ancient DNA is an important tool in the study of disease in the past. Some pathogenic bacteria invade the bones and teeth, leaving traces of their DNA in the skeleton after death. By extracting and sequencing the bacterial DNA, it is possible to confirm the presence of a disease, and to study changes in the genetic features of the pathogenic bacteria. We are using next generation sequencing methods to obtain detailed genotypes and complete genome sequences of Mycobacterium tuberculosis strains responsible for tuberculosis in the past. We are particularly interested in linking strain variations to changes in TB virulence during the medieval period, when Britain became increasingly urbanised.
Genetic profiling of archaeological skeletons
Ancient DNA has considerable potential as a source of genetic data relating to the kinship affiliations of human skeletal remains, information that would enable archaeologists to make more accurate interpretations of social organisation at individual sites and across communities. Kinship data are impossible to obtain by conventional osteology but is attainable by genetic profiling. We are currently using ancient DNA to obtain information on kinship between groups of human burials from various sites in Britain and the rest of Europe.