Philippa Ryan, Scientist, British Museum
Archaeobotany is the study of ancient plant remains, and I joined the field team at Amara West in Sudan earlier this year to collect samples for archaeobotanical analysis. Charred plant materials were retrieved on-site from sediments through dry-sieving and flotation. These samples were subsequently brought back to the British Museum for further sorting and identification.
At the moment I am analysing the charred seeds and fruits with Caroline Cartwright, who is also analysing the wood charcoal. The macroscopic plant remains are analysed using both a stereo microscope and a SEM (scanning electron microscope). Charred remains found so far include cereal grains (wheat and barley) and crop-processing waste, fruits such as figs and a wide range of wild plants.
I am also processing sediment samples to extract phytoliths (microscopic plant remains), which are formed when soluble silica taken up in groundwater by plants is deposited within and between certain plant cells. These silicified cells are found within many different plant families such as grasses (which include cereals), sedges and palms.
Phytoliths are difficult to identify, but have the advantage of surviving in both charred and non-charred contexts, so we can learn about the presence and use of plants in areas where seeds and grains don’t survive.
At the moment, I am processing sediments to extract phytoliths, which includes the removal of carbonates, clays, organics, other remaining non-siliceous material through heavy liquid flotation, and finally mounting dried phytoliths onto slides. Phytoliths are then identified and counted using an optical (light) microscope.
Analysis of these different types of plant remains helps us learn about the past uses of plants at Amara West in day-to-day life, such as for food, fuel and animal fodder. I am also looking at the distributions of seeds and phytoliths across the site to examine locations of plant based activities such as food processing, as well as whether there are any differences in diet between poorer and richer households, or across the history of the site.
Plant remains can also help to provide information about the nearby vegetation, for instance the types of grasses, wetland plants and trees that grew near the ancient town.