1 Introduction
The changes in lifestyle during the Mesolithic-Neolithic transition have been studied extensively by many scholars. They address themes like subsistence and settlement strategies, mortuary variability, demographic composition, health, and lately especially migration and diet.
For decades the relation between the health status and living circumstances has been studied and debated (e.g. Cohen & Armelagos 1984). Major topics in these discussions are the changes in demography and health brought on by the agricultural transition on a worldwide basis. These studies include ethnographic groups and archaeological populations based on skeletal series. Angel (1975) analysed the skeletal evidence from Eastern Mediterranean populations and pioneer work was performed by Acsádi & Nemeskéri (1970), who established the mortality profiles of Hungarian groups from the Palaeolithic period onwards. While the introduction of agriculture holds advantages associated with a sedentary way of life and food production leading to population growth (e.g. Bocquet-Appel & Dubouloz 2004), disadvantages existed as well in respect to crop failures, a less variable diet and the spread of all kinds of infectious diseases. An overall view emerged from these studies that anticipated a decline in health with regard to nutritional stress, physical workload, stature and life expectancy for the early Neolithic period (e.g. Cohen & Armelagos 1984; Roosevelt 1984; Wittwer-Backofen & Tomo 2008).
An important aspect in the study of past populations has always been the debate on their local origins, large-scale or small-scale migration. The question is of special interest in the debate on the process of ‘Neolithisation’, the spread of agriculture. For long it was attempted to answer these questions on the basis of artefact typology and/or metrical anthropological evidence, but both approaches appeared to be untenable. The solution to this dilemma has come within reach with the development of isotopic research and its application to archaeological bone material, human as well as animal. The ratio of strontium isotopes especially appeared to be highly significant for geological formations and as such to provide a tool to discriminate between locally grown and non-local individuals. The application to Bandkeramik cemeteries in south-western Germany, especially the analysis of tooth enamel, showed that the communities had a heterogeneous composition. Quite a number of native people from the upland, especially young women, were integrated into the loess-bound Bandkeramik communities (Bentley 2007).
The change in diet, defined by the introduction of domestication and cultivation, is a crucial element in the Neolithisation process. One of the aspects is the consumption of fish, which is supposed to decline throughout the transitional period in favour of terrestrial food sources like domesticated animals and plants. Several trajectories of the Neolithisation process are observed in northwestern Europe. In some areas – like Britain and Denmark – a rapid shift in subsistence is attested (Richards et al. 2003a, 2003b). More recent research has revealed however that a sharp shift cannot be observed in the whole of Denmark: both, Mesolithic and Neolithic, populations had a diet with a substantial aquatic component (Fischer et al. 2007a, 2007b). In Southern Sweden the coastal populations held onto their own traditions longer and changes in diet were subtle and gradual (Lidén et al. 2004). In other areas, Brittany and the Meuse valley, comparisons between Mesolithic and Neolithic sites are difficult and no clear view emerges on the nature of the transition (Schulting 1998; Schulting & Richards 2001; Bocherens et al. 2007). Apparently evidence and views differ on the progression in the adoption of new subsistence strategies and changes in diet. This is understandable as the Mesolithic and Neolithic sites are often situated in different ecological settings and cultural traditions concerning the exploitation of the local surroundings may have been of influence on this progress. Comparisons are moreover hindered by the fact that Mesolithic and Neolithic sites often are situated in different (sub)regions. Even if Mesolithic sites were present in the immediate neighbourhood of Neolithic ones, the exploitation of a variety of habitats would result in an isotopic blend of seasonal food sources, with for instance an alternating regime of a more aquatic and a more terrestrial diet during the year.
A series of sites in the wetlands of the Lower Rhine Basin, dating from the Late Mesolithic and Middle Neolithic, have been excavated and produced a considerable number of burials and consequently human skeletal remains. This material offers the opportunity to present a Dutch contribution to the study of these themes. Archaeological, physical anthropological and stable isotope analyses are integrated to investigate these changes in the way of life during the transitional period. An overview of the relevant sites is presented here based on the publications by various scholars. The information on the mortuary variability and physical anthropological data are derived from these publications. New is the application of stable isotope analysis to the research on migration and diet.
An earlier stable isotope study (Smits et al. 2008) concentrated on material from the Schipluiden and the Swifterbant sites. This investigation was performed in cooperation with the University of Durham, and enabled us to identify some immigrants in the two Middle Neolithic populations of Swifterbant and Schipluiden. The results of that study will be integrated here. That research has been extended with cooking residues from Schipluiden pottery and samples from human and animal bones from both Hardinxveld sites (Polderweg and De Bruin).