Carbon and nitrogen stable isotopes as tracers of change in diet breadth during Middle and Upper Palaeolithic in Europe

Carbon and nitrogen stable isotope ratios in fossil bone collagen have been used as evidence for an increase of diet breadth between Middle Palaeolithic Neanderthals and Early Upper Palaeolithic anatomically modern humans. In this paper, we revisit the rules of palaeodietary reconstruction using collagen stable isotopes and reassess the possible isotopic signatures of potential protein resources available to prehistoric humans. It appears that the interpretation of the human's isotopic signature does not necessarily imply a significant proportion of aquatic-derived protein in the diet neither for Neandertal nor for first anatomically modern humans in Europe. Exploitation of aquatic ecosystems by humans needs to be supported by further zooarchaeological evidence. Nevertheless, isotopic biogeochemistry of fossil human collagen can be very useful in palaeodietary reconstructions provided that basic rules are followed while selecting samples of coeval fauna, in order to establish the end members of different food resources. Significant progress investigating the evolution of subsistence strategies in fossil hominids is expected from a combination of zooarchaeological and isotopic data. Copyright (C) 2004 John Wiley Sons, Ltd.