Each indicator of Neolithic subsistence discussed above addresses a different aspect of diet or dietary behaviour on differing scales, thus each has inherent biases and weaknesses. Furthermore, each is dependent, to some degree, on the state of preservation of the material to be analysed. This situation can make it difficult to compare two or more proxies in a valid way and it is impossible, in most cases, for one proxy to be used as an independent check on another one. Bearing these issues in mind, it is still possible to make a number of conclusions based on these data.
Central to the question of Neolithic subsistence is the question of cereal cultivation. Cereals are known from a wide range of different type throughout the Neolithic period in Scotland, and continue to be discovered regularly. Their importance as a food is also suggested by dental work, and corroborative evidence exists in the form of field systems, indicators of soil tillage, and quern stones. Known examples of which tend to date to the later part of the Neolithic, introducing the possibility that cultivation practices were forced to respond to the centuries of damage caused by intensive agriculture and erosion in the earlier phases of the Neolithic. This may be stretching the available evidence to a considerable degree, but it highlights the central fact that cereal cultivation cannot be dismissed as a marginal activity, rather it probably played a pivotal role in the structure of society and economy, from the beginning of the Neolithic onwards-an hypothesis that future work will continue to test with AMS dating of the cereals themselves and stable isotope studies of manuring practices and midden material.
The absence of formal field boundaries in mainland Scotland suggests that although cereal cultivation was relatively commonplace, it probably took place in ‘garden-plots’ and / or woodland clearances rather than within formalised fields. And patterns of cereal agriculture and domestic animal exploitation are markedly similar. Evidence for each is both as geographically widespread as the available data allows and occurs throughout the period of interest. Sheep and cattle were the most important animals in Neolithic Scotland (or rather Orkney and Harris, as data from elsewhere are largely unavailable), especially cattle when meat weight rather than bone frequency is considered. Pigs were apparently relatively unimportant, in contrast to sites in Southern Britain, perhaps reflecting the environment and lack of forest cover in the Northern and Western Isles. Unlike sheep and cattle, pig farming does not involve the production of secondary products, so perhaps animal husbandry practices were deliberately structured in this way.
The patterns of cereal agriculture and domestic animal exploitation are markedly similar. Evidence for each is both as geographically widespread as the available data allows and occurs throughout the period of interest. Sheep and cattle were the most important animals in Neolithic Scotland (or rather Orkney and Harris, as data from elsewhere are largely unavailable), especially cattle when meat weight rather than bone frequency is considered. Pigs were apparently relatively unimportant, in contrast to sites in Southern Britain, perhaps reflecting the environment and lack of forest cover. Unlike sheep and cattle, pig farming does not involve the production of secondary products, so perhaps animal husbandry practices were deliberately structured in this way. As Parks (2009) suggests, the lack of seasonality in Orcadian Neolithic fishing may be due to the fact that certain species are only abundant in the autumn, hence conflicting with the labour requirement of the cereal harvest. The potential for marine resources to have been ‘taboo’ amongst early farmers has also been suggested (Schulting & Richards 2002).
It is clear that much of the above discussion is heavily geographically biased, especially towards Orkney. This is perhaps unavoidable at present. Future work with lipids and plant macrofossils has the potential to address this issue and provide a space-time model of subsistence practices in Neolithic Scotland that is not as geographically imbalanced. Indeed, a recently-completed major research project at the University of Bristol, 'Changing patterns of marine product exploitation in human prehistory via biomarker proxies in archaeological pottery' (NERC-funded), has been doing just that with its lipid analysis of a considerable number of samples of Neolithic (and later) pottery in various parts of Scotland.
Outstanding research questions
While understanding of Neolithic diet and farming practices has increased significantly over the last two decades - especially through the application (over the last decade) of isotopic and lipid analysis - there nevertheless remain fundamental gaps, as follows:
- Very little is known about the specific cultivation practices and herding strategies of these farming groups, and our list of cultivated plant materials may well be incomplete.
- Flax has been noted at Balbridie, but to what extent was it cultivated, and was it principally a food crop (as opposed to a source of fibres for fabric manufacture and cordage)?
- How typical or atypical is the Orcadian evidence for subsistence strategies?
- How do deer fit into the equation? It has been suggested that they may have been deliberately introduced to the Orkney Islands, just as they had been introduced to Ireland, but do they constitute a partly-managed, partly-wild resource? How is the enigmatic evidence from the Links of Noltland - where a pile of deer carcases had been left, unscavenged and with a large fish on the top of the heap (Sharples 2000) - to be explained?
- To what extent were marine resources used as foodstuffs at different times and in different parts of Scotland?
- Is the elevated nitrogen isotope level that has been found in human remains in Orkney an indicator of the practice of manuring?