Archaeology and the natural environment

Dr Mike Allen has an unusual expertise: snails. Snails are important to archaeologists because they can tell us a lot about the past – snail shells from thousands of years ago still survive and can tell us about the natural environment at the time we are interested in.

For instance, some types of snails prefer open countryside, some prefer woodland. If we find the shells of the former types and none of the latter around a find, we know that at that time the landscape would have been open countryside, however much it has changed since.

“When carrying out an analysis of shells found at an archaeological site, I will typically take away small bags of soil and examine the shells found there," said Dr Allen.

“Some species will only exist in certain types of habitat, so we can start to recreate the environment at the time they existed from their presence.”

During his career, Dr Allen has examined thousands of snail shells. At one site in Dorset, for example, he looked at 135,000 shells in 350 samples from 17 sites weighing almost half a tonne. By examining snail shells and pollen at the site at Cranbourne Chase, Dr Allen was able to show how dense deciduous woodland was gradually cleared by Stone Age farmers from around 4,500 BC, and by 2,000BC all the land was used for dairy and crop farming.