Developing radiocarbon dating of bone amino acids: refining chronology and resolving dietary and reservoir effects.

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Note that this is a common summary for the linked proposals The carbon isotopes in protein that survives in archaeological human bone come from the food that was eaten, and so they record a basic vital aspect of our past struggle for existence. One isotope, radiocarbon, also enables us to measure the time since the food was eaten. An interesting complication arises when the food is from the sea, or from rivers or lakes. In such cases, radiocarbon dates are often erroneously old due to 'radiocarbon reservoirs' arising from geochemical effects between the atmosphere and the organisms being eaten. We have developed a method which is able to dissect this complication, and use it to unravel both the error in the dating, and to estimate the extent to which such aquatic resources were being consumed. Our method is able to measure individual components (amino acids) in the protein, and compare those which are known to have different dietary origins (i.e. the essential and non-essential amino acids). In this research we aim to develop the laboratory method to a fully robust state, and then test it over a range of suitable applications, where dates or diets are in question. This new method will enable the radiocarbon dating of human remains to be made more accurately, since the effects of radiocarbon reservoirs can be detected and avoided. At the same time, it can provide definitive evidence, which can be quantified, for freshwater fish consumption. Our project here builds the foundation for such a study in Europe. The eventual goal is to understand the role of freshwater fish consumption during the transition to farming that swept across Europe some 8000 years ago. Rather little is known about the continuation of fishing, even though rivers were important for migration and settlement, because the evidence has been hard to obtain. It seems that fishing probably ceased in some areas (as also with sea-fishing) but continued in others. This new methodology will sharpen the chronology, and the understanding of subsistence, of how rapidly the Neolithic way of life took root across Europe. We make a start by addressing the best studied area of the Danube Basin.