The Work

Specialist Report 2004 - Animal Bone

Posted by steven on 11/04/2005 at 02:12 PM

ANIMAL BONES FROM UAMH AN ARD ACHADH (HIGH PASTURE CAVE), SKYE: INTERMEDIATE REPORT

Carrie Drew - University of Durham

A preliminary analysis of the animal bones from Uamh An Ard Achadh was undertaken on 16th March 2003 by Peter Rowley-Conwy of the University of Durham, who highlighted features of the assemblage which indicated that a full analysis of the bones would be beneficial (Rowley-Conwy, 2003).

Unusual features of the assemblage identified:

· That the majority (c.80-90%) of the bones are pig (Sus Scrofa). This is unexpected as the present climate of Skye is unsuited to pig rearing and there is no indication that the climate would have been dramatically different in the past, meaning that while pigs could have survived their role as a food animal would have been limited.

· There is a large frequency of cut-marks on the bones, confirming processing by humans.

· Despite the evidence of processing a large proportion of the pig long bones are complete. This is unusual, as the marrow in bones is an important source of nutrition and we would normally expect to find long bones fragmented to obtain this. This may suggest a ritual context for the Uamh an Ard Achadh bones similar to at the major late Neolithic ritual site at Durrington Walls where a large sample of pig bones had clearly been processed but were also largely unbroken (Albarella and Serjeantson).

· The pigs appear to be of small stature, which seems to indicate domesticated pigs rather than wild boar as wild boar in North-West Europe are generally larger than domestic pigs (Rowley-Conwy, 2003) .

· Most of the pigs were killed at a young age, prior to dental maturation and around the age of 8-11 months old, although two of the mandibles were older- around 18-22 months old. These ages are approximate, but may suggest that both age classes were killed at the same time, in winter (if a seasonal April birth date is assumed).


Figure 1.  The cleaved skull and mandible fragments of pig from Bone Passage.

Following the recognition of the significance of this assemblage it was decided that a University of Durham Archaeology master’s student would undertake a full analysis of the bone assemblage under the supervision of Peter Rowley-Conwy, with analysis and write-up to be completed by September 2005. This analysis is on-going and at an early stage, so firm conclusions can not yet be drawn from the further study of the assemblage. From the beginnings of this analysis however, several additional areas of interest have already been identified for further examination.

· Upon examining the assemblage as a whole it is clear that the top layer (context 1) is of very different composition from the layers excavated from trench 1 within the cave. On a preliminary examination the trench material appears to represent a far more usual “domestic” assemblage of material, and the contrast between this and context 1 may be significant and emphasise the unusual nature of the assemblage in context 1. The bones from context 1 consist predominantly of pig (Sus Scrofa) (c.90% of the assemblage), whereas the trench material contains a more usual distribution of those species we would expect to find in domestic material of the late prehistoric period. This may suggest a changing or differing usage for the cave in relation to deposition of material and indeed the later deposit (context 1) may reflect a “special” deposit, whereas the earlier deposition does not.

· The assemblage within context 1, which is dominated by pig remains appears to comprise sufficient remains to represent the larger part of at least 7 or 8 pigs. It can not be confirmed whether these remains represent whole individuals or bones from many individuals, but it is clear that some of the bones are of suitably similar age (through fusion data) to be from the same individual or individuals at very similar stages of development. This may suggest a single deposition event, or deposition at particular times of year, an aspect to be explored further within the study.

· The large amount of chop and cut-marks on many of the bones appear to have been largely created by metal tools. This may reinforce the idea of ritual significance, especially if evidence of metal-working on site is found to be present, as Iron working is often associated with ritual contexts in Scotland (Hingley, 1998).


Figure 2.  Rib bones of pig showing butchery marks made using a metal blade.

· It is apparent that the pig bones are more complete than those of other species (for example cattle, sheep/goat) with the other species showing far more frequent evidence of deliberate breakage. While it is possible that this is due to the difference between the context 1 and trench deposits, further examination will elucidate whether this further represents different treatment of the pig remains.

It is clear that further analysis is necessary to understand the nature of this assemblage, and to investigate the unusual aspects of the pig-rich context 1 contrasted to the depositions found from within the other contexts. The unusual composition of the bone assemblage leads us to believe that its investigation may prove diagnostic in understanding the nature of the site at Uamh An Ard Achadh, and may shed light on the use of the animals at this location. The particularly good preservation of the assemblage also allows us to investigate the husbandry of pigs on Skye, an important opportunity for investigation as preservation of animal remains is generally so poor in the Hebrides.

Work to be completed within the analysis of the assemblage:

· Firstly to identify all of the species included in the assemblage and investigate whether the remains represent complete animals, or whether there are patterns in the parts deposited suggesting differential deposition. For example, do the bones represent high-quality cuts? This is particularly important on a site where there is a suggestion of ritual deposition, as it can be seen from other sites in Scotland that deposition of articulated joints in ritual contexts is a common pattern (Mulville et al., 2003).


Figure 3.  Long bones recovered from the cave showing breakage to aid the extraction of marrow.  This was only found on animal bones other than pig from the upper contexts identified in Bone Passage.

· Tooth eruption, epiphysial fusion and wear of teeth will be recorded and analysed to confirm the age of animals present, and to provide evidence for seasonality within the deposition. This will also allow us to explore the evidence for whether the “unusual” context 1 assemblage could have been deposited within a single event (or a yearly event held at the same time each year) or whether there were multiple depositions over various times of year.

· The processing evidence will be recorded and investigated to study how the remains have been treated before deposition. It is planned that a comparison of the uniformity and frequency of the working will be undertaken, and a consideration of what butchery strategies these suggest.

· This site, with its unique deposits, offers not only an opportunity to learn about husbandry in Skye at this period but a comparison with the faunal assemblages across Scotland. This may increase understanding of how unusual (or not) the assemblage is, particularly in relation to other cave or souterrain deposits of similar date and it is important to determine where the assemblage fits into a wider consideration of the significance of the use of pigs in Scotland.

Summary of strategy proposed for full examination of the Uamh An Ard Achadh bone assemblage to be completed by September 2005:

· Identification and recording of the bones present in the assemblage.

· A consideration of the contrast between context 1 bone assemblage and the assemblages of the other layers.

· A consideration of the distribution of the bones from individuals, studying age indicators (epiphysial fusion and tooth eruption/ wear) to assess what portions of animals are present and the minimum number of individuals present. Analysis of the patterns gained from this as to whether it suggests selective deposition, butchery on-site or movement of animal portions, and the information it gives about herd structures.


Figure 4.  A wide range of animal teeth were recovered from Trench 1.

· A consideration of the cut-marks and other working evidence to determine the uniformity of butchery techniques and to consider the strategies used in processing the animals as well as to examine the relationship between species and the amount of processing. In particular a study of the evidence for the apparent deliberate lack of breakage of pig long bones in comparison to the other species and a consideration of possible reasons for this.

· A study of seasonality and age indicators, in particular evidence from epiphysial fusion and tooth eruption as well as linear enamel hypoplasia, to consider evidence for seasonal deposition of the assemblage- whether it could represent a singular or yearly event or deposition throughout the year.

· Comparison to other sites of similar type, such as Durrington Walls (Albarella and Serjeantson, 2002), which appear to exhibit similar patterns of pig processing and a comparison to other sites of unusual nature in Scotland such as A’Cheardach Mhor, South Uist and Sollas, North Uist (Finlay, 1984) to attempt to understand where this site fits into Scottish Archaeology.

· A study of microwear upon the teeth to determine the diet of the pigs and to consider evidence for husbandry techniques, especially considering the extreme conditions of Skye and the implications for the unusually high amount of pigs present and the strategies which may have been employed to enable the survival of this species.

The High Pasture Cave site from preliminary examination appears of unique nature, with few parallels across Scotland or Britain. This importance emphasises the contribution that the faunal assemblage is anticipated to make to understanding of the use of animals in Scotland in the later prehistoric period, and a greater study of the assemblage is hoped to elucidate both the composition of the assemblage, and whether the assemblage represents a “special” or routine deposit, as well as aiding the greater understanding of the link between the underlying cave and the surface features at Uamh An Ard Achadh.


Figure 5.  The canine of a juvenile brown bear recovered from Trench 1, Context 9.

Bibliography:
· Albarella, U. and Serjeantson, D. 2002. “A passion for pork: meat consumption at the British Late Neolithic site of Durrington Walls”. P.33-49 in Miracle, P. and Milner, N. (eds.) Consuming Passions and Patterns of Consumption. Cambridge: McDonald Institute for Archaeological Research.
· Finlay, J. 1984. Faunal evidence for prehistoric economy and settlement in the Outer Hebrides. Edinburgh, University of Edinburgh Unpublished PhD thesis.
· Hingley, R. 1998. Settlement and sacrifice: The later prehistoric people of Scotland. Edinburgh, Historic Scotland.
· Mulville, J. Pearson, M. Sharples, N. Smith, J. and Chamberlain, A. 2003. “Quarters, Arcs and Squares: human and animal remains in the later Hebridean Iron Age”. P. 21-34 in Downes, J. and Ritchie, A. (eds.) Sea Change: Orkney and Northern Europe in the Later Iron Age, AD 300-800. Angus, The Pinkfoot Press.
· Rowley-Conwy, P. 2003. “Early domestic animals in Europe: imported or locally domesticated?” In Ammerman, A.J. and Biagi, P. (eds.) The widening harvest: the Neolithic transition in Europe. Boston, Archaeological Institute of America.
· Rowley-Conwy, P. 2003. “Pig bones from Uamh an Ard Achadh, Skye: Preliminary report”. P.36-37 in Birch, S. Wildgoose, M. and Kozikowska, G. (eds) Uamh an Ard Achadh (High Pasture Cave) Kilbride, Skye: A preliminary report- July 2003. West Coast Archaeological Services.


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