A team of bio-archaeologists from York were able to provide the final piece of scientific evidence which confirmed that primitive stone tools discovered in East Anglia dated back around 700,000 years 200,000 years earlier than any other traces of human colonisation of northern latitudes.
Dr Kirsty Penkman and Dr Matthew Collins were part of an international team, headed by the Ancient Human Occupation of Britain (AHOB) project, which studied the worked flint flakes discovered two years ago in a cliff at Pakefield near Lowestoft, Suffolk.
After members of the international team used stratigraphy to indicate the likely age of the flints, the York scientists were called in to confirm the antiquity of the artefacts using a newly-refined technique of amino acid analysis. The technique measures the extent of deterioration of proteins in fossils found close to the flints - in this case, opercula, the tiny trap-doors that close a snail's shell.
The results of the research are published in the latest edition of Nature today (Thursday 15 December 2005).
Dr Penkman, an Associate member of AHOB, said: "The amino acids were very securely contained in enclosed crystals of the opercula, unchanged by environmental factors other than normal internal protein degradation. In effect, they are a protein time capsule, enabling us to confirm the Pakefield opercula were significantly older than 500,000 years, the previous earliest date for humans north of the Alps."
Dr Collins said: "The method relies upon measuring the products of decomposition, so we had to isolate a protein sample that was well protected and did not leak the products of decay."
Dr Penkman added: "Helping to demonstrate the antiquity of the Pakefield site has been very exciting, and we are now trying to apply the same technique to
Contact: David Garner
University of York