Introduction

NeoMilk: The milking revolution in temperate Neolithic Europe.

The NeoMilk project explores the introduction and spread of cattle-based agriculture by early Neolithic Linearbandkeramik (LBK) farmers and its implications for modelling the Mesolithic-Neolithic transition in Northern and Central Europe during the 6th millennium BC.

  • Lipid biomarker and stable isotope compositions of food residues from LBK pottery containers will provide qualitative and quantitative assessments of the major animal products acquired and processed in LBK pottery (Theme 1, R.P. Evershed and M. Roffet-Salque).
  • The study of domesticated animals during the LBK (herd management, meat production and milking) will be led by A. Bentley, J.-D. Vigne, A. Outram and J. Smyth (Theme 2).
  • Patterns of animal management and milk use will be chronicled, mapped and correlated to environmental as part of Theme 3 (V. Heyd, A. Marciniak and M. Thomas).

The project is funded by an ERC Advanced Grant (2013-2018) accorded to Richard P. Evershed.Figure 1. Distribution of LBK sites.

The LBK is characterised archaeologically by a consistent material culture comprising distinctive pottery, stone technology and characteristic house and settlement forms. The consistency of the material cultures belies a greater diversity in social, cultural and economic activities; this is becoming evident through more multi-discipline assessments of the available archaeological information and, critically, the application of new scientific methodologies.

Crucially, faunal remains from LBK sites point to considerable regional variation in the extent to which local hunting-gathering traditions were abandoned or subsumed by a pastoral system(s). Cattle are generally thought of as the ubiquitous LBK domesticate, but closer examination of available data suggest considerable geographical, temporal, regional and sub-regional variation, with a cattle-based economy only becoming a consistent feature of the LBK after the end of its first phase of spread.

There is also new evidence, at the settlement level, of subsistence specialisation (Bogaard et al. 2011), while recent pilot work on organic residues from LBK ceramics has revealed specialisation in the use of different vessels forms to process different animal products, with evidence of diachronic and regional variations (Salque et al., 2013).

Hence, this project will focus on one of the most profound dimensions of the lives of these early farming communities, namely the emergent role of domesticated animals in their evolving subsistence economies and settlement cultures, particularly the factors that underlie cattle becoming the domesticate of choice amongst temperate European Neolithic farmers. Central to this investigation is the typologically distinctive pottery that defines the LBK culture and opportunities offered by the organic residues they preserve as a major new source of bioarchaeological, radiocarbon dating and environmental information. These residues hold the key to understanding the changing role(s) of animals in the diets, economies and evolutionary genetics of LBK people.

New research dimensions in bioarchaeology and the organic residue revolution: lipid-based proxies of vessel use, diet and agriculture

Figure 2. Use of stable carbon isotope values of fatty acids from pottery vessels to identify milk use in SE Europe and the Near East (each  point on the plots represents a residue from an individual pottery vessel). The red shaded box shows the region of most intensive milk use at sites dating to 6.5 ky BC.

A paradigm shift over the past twenty years allows entirely new archaeological questions to be addressed through new scientific methodologies. Arguably, the most significant has been the characterisation of a wide range of biochemicals that survive in the archaeological record, e.g. lipids, DNA, proteins, etc., derived from human and animal remains related human activity in the past. The study of ancient DNA has benefitted from the development of polymerase chain reaction, and more recently through the latest generation of high-throughput sequence techniques, providing information from human remains of value in investigating kinship, evolution, and population movements. The structural protein collagen obtained from skeletal remains routinely provides 14C dates, while its carbon and nitrogen isotope composition can provide information on ancient diet based on the ‘you are what you eat’ principle to reveal dietary shifts in prehistory. In domesticated animals stable isotopes provide important information relating to foraging behaviour and management strategies.

Pottery as a cultural and economic archive

Pottery has been shown to possess the remarkable capacity to preserve cultural and economic information in the form of biochemical remains of the commodities processed or stored therein, allowing determination of the specific uses of pottery vessels (Evershed 2008a,b).

Significantly, the widespread occurrence of animal fats in Neolithic cooking pottery reveals previously unknown aspects of the acquisition and processing of animal products.

Identification of dairy residues in pottery

Our direct identification of dairy residues, using a fatty acid-based stable carbon isotope proxy (Dudd & Evershed 1998), has allowed extensive testing of the Secondary Products Revolution hypothesis (Sherratt 1983). These investigations confirm that dairying was an established component of the agricultural package when it arrived in Britain in the late 5th/early 4th millennium BC (Copley et al. 2003, 2005), and has provided the earliest evidence for the milk use in NW Anatolia in the 7th millennium BC (Evershed et al. 2008).

A consistent observation we have made from studies at more than 50 sites in the UK and the Near East is the remarkable frequency with which milk fat residues occur in pottery, especially when cattle are strongly represented in faunal assemblages (e.g. Fig. 2). This has led us to the hypothesis that intensive milk use by Neolithic people was the direct consequence of the adoption of cattle as part of their farming economies (Copley et al., 2005; Evershed et al. 2008; Cramp et al. unpublished data).

The fundamental research problem: When, where and why did the transition to full domestic animal-based farming occur in the LBK?

Our pilot organic residue studies of pottery from a handful of LBK sites, performed as part of LeCHE, show an absence of milk fat residues at 2 early German LBK sites (where wild fauna were prominent) and a clear milk fat signal at a late LBK Polish site (where cattle were dominant; see below). These preliminary organic residue analyses highlight the critical question, namely: where and when did dairying arise in temperate Neolithic Europe?

This question centres on the spatiotemporal patterning of domestic animal use amongst the first temperate farmers of Europe, traditionally addressed through zooarchaeological analyses of faunal assemblages. At the early stages of domestication interpretations are based upon the gradient between wild and domestic fauna, through the following three phases of the assemblages:

(i) a dominance of wild fauna indicating hunters or hunting sites;

(ii) a balanced mixture of domestic and wild fauna, indicating Neolithic subsistence but with a hunting component;

and (iii) a dominance of domestic sheep/goat, pig and cattle, which constitute specialised Neolithic subsistence (Tresset & Vigne 2007).

Statistical analyses of these assemblages have shed light on exploitation patterns, species representations and herd structures. Meat utility indices provide important economic information, which underpin settlement population estimates, since protein underpins subsistence. Morphological investigation of animal bones provides evidence of butchery practices, marrow extraction and fat recovery.

Our focus on milk use is because of its special importance in sustainable subsistence strategies based on domesticated ruminants, due to its exceptional nutritional density, i.e. high calorific value and protein content and source of vitamin D, calcium and other micro-nutrients. Sustainable milk production also avoids the need to slaughter precious stock (Sherratt 1983) and thus provides greater constancy of nutrient supply than the ‘boom-and-bust’ of seasonal harvests.Figure 3. Approximate posterior density of region of LP/dairying co-evolution.

Regular consumption of whole fresh milk requires a Lactase Persistent (LP) gene variant, which is now widespread amongst modern northern Europeans (Itan et al. 2010). Expression of the LP gene results in continued production of the enzyme lactase into adulthood, such that lactose could be digested and hence whole milk consumed. The absence of the enzyme gives rise to the condition known as lactose intolerance, whereby the consumption of moderate quantities of milk can result in discomfort and diarrhoea. Thus, perhaps more than any other, this genetic change so prevalent in Europeans underpins the economic importance of dairying, driven by the decisions of ancestral farmers to harness milk as a sustainable dietary staple.

Recent spatially explicit gene-culture co-evolution modelling suggests the LBK underlies the evolution and distribution of the main European LP-associated gene variant (-13.910*T). The origin of this gene is inferred to be between the Balkans and central Europe around 7,500 y ago (Fig. 3; Itan et al. 2009). Interestingly, investigations of ancient DNA from the skeletal remains of Neolithic farmers from the region have so far failed to detect the -13.910*T variant (Burger et al. 2007). This is consistent with the modelling results as both dairying and the LP allele are unlikely to have spread uniformly over Europe and would initially have been rare, making the early use of milk unlikely to be detected genetically (Burger et al. 2007). This brings us back to our central question where and when (and indeed why) did dairying arise in temperate Neolithic Europe?