δ13C-values of dog bones reveal the nature of changes in man's food resources at the mesolithic-neolithic transition, Denmark

Abstract

Carbon isotope ratios of bone collagen yield important information on the nature of the main diet utilized by man. Non-marine food is characterized by significantly lower δ 13C-values than food of marine origin. Isotopic analysis of prehistoric dog bones may give important data supplementary to those obtained from the rare prehistoric human skeletons provided the dogs utilized the same basic food as man at the same site, and that the resulting isotope ratios are the same. This hypothesis is supported by analysis of skeletal material from two late Mesolithic and one early Neolithic site, where the same carbon isotope ratios are found for both dog and man. Isotopic analysis of the available Mesolithic dog material clearly indicates that dogs from inland sites chiefly thrived on a non-marine diet, whereas the food of dogs from coastal sites was of marine origin. The same pattern also seems to apply to human beings from the two types of sites. The measured difference in isotopic values of bone collagen at the coastal sites between Mesolithic hunter-gatherers and early Neolithic farmers is ∼6%o. This value confirms the mixed hunting-gathering food sources of man from the early Neolithic coastal sites, and shows that the agricultural food plants and animals constituted ∼ 70% or more of the total diet. This pattern in the transition from hunting-gathering to agriculture can be traced in many parts of the world.