The Work

Specialist Report 2005 - The Mammal Bone Assemblage (Butchery at High Pasture Cave)

Posted by steven on 13/02/2006 at 04:15 PM

REFUSE OR RITUAL? - THE MAMMAL BONES FROM HIGH PASTURE CAVE, SKYE

Carrie Drew - University of Durham

Chapter 6: Butchery at High Pasture Cave

At High Pasture Cave a large percentage (c.40%) of the bones have marks from working, and a consideration of these may determine whether this processing was for meat, marrow or other purposes and allow a reconstruction of butchery techniques (Egeland, 2003:39).

All of the cut/ chop marks in the assemblage have a regular profile and appear cleanly cut, consequently they have been interpreted as of metal origin. This is supported by the evidence of metalworking on site, in the form of slag deposits, copper-alloy fragments and hammer-scale from within Trench 1 and surface excavations (Birch, 2005: Web reference 2). When available, as they apparently were at High Pasture Cave, metal tools would have been preferred, being stronger and retaining a cutting edge far longer than stone (Greenfield, 2000:97). The working on the bones appears to be of two types; predominantly cutmarks, both fine and deep, but also with instances of deep chops made with a larger “cleaver” type instrument. The working on the Zone 3 pig bones exhibit no evidence of the “cleaver” tool being used, with only cutmarks visible, while the Zone 2 and Zone 5 cows exhibit working of both types.

One of the particular problems in studying archaeological faunal assemblages is when bones are heavily damaged through gnawing by animals (Payne and Munson, 1985:31). At High Pasture Cave this appears to be a limited problem, with very few of the bones from Zone 3, Zone 2 and Zone 5 (the “unusual” deposits) exhibiting any evidence of animal damage at all. Any that is present is very limited and does not obscure bone detail. With domestic assemblages gnawing is the norm and the lack of gnawing at High Pasture Cave is unusual in itself, suggesting collection and swift deposition into the cave before animals could access the remains. There are slightly higher instances of gnawing throughout the other “normal” deposits within the cave, which may suggest more of a delay before disposal as might be expected in usual domestic use, although gnawing in general is very limited.

Section 1: Butchery of the Zone 3 Pigs

To determine patterns of working on the pig bones, diagrams have been created of the position of the working on the bones, as advocated by Guilday (1962) and commonly used in examinations of butchery marks (for example, Binford, 1981; Luff, 1994 and Farello, 1995). Butchery marks represent the remains of man “taking an animal apart to suit his purposes” (Binford, 1981:91) and so some understanding of the process may illuminate the intention behind the treatment of the skeleton. The diagrams demonstrate regularity in the patterns of working on the bones suggesting that the whole Zone 3 assemblage was worked in a similar way and with a similar knife type. This may suggest a singular event, or at least a consistency of intention behind the disposal.

The majority of working on the Zone 3 pigs reflects dismemberment and filleting suggesting that the Zone 3 pigs were worked for meat. The evidence for filleting is relatively limited, with the majority of the working marks being defined as due to dismemberment. All groups within examinations of butchery among ethnographic societies (such as in Binford, 1981) practise dismemberment to gain meat. This involves separating the front leg from the axial skeleton and further partitioning between the radio-ulna distal end and carpals (at High Pasture Cave the leg division appears to have been below the carpals), also separating the rear leg from the vertebrae, either by removing part of the pelvis with the leg, when using large tools, or separating the femur from the pelvis (Binford, 1981:91). It appears in this case that the latter form of dismemberment of the hind legs was practiced, with there being no major large toolmarks, instead similar cutmarks to those found on the rest of the body. As all skeletal elements are present within the assemblage the suggestion is that butchery was occurring on site.

Unlike the vast majority of ethnographic and archaeological assemblages the Zone 3 pig bones show no evidence of having been broken to access the marrow. The fat contained in the medullary cavities, known as marrow, is of far higher calorific value than anything else in the diet of prehistoric people (Outram, 2001:401). The exploitation of bone fats is almost ubiquitous in the past either as a source of food, or as grease or fuel (Grigsom, 1999:226). The only way of accessing such resources is to smash the bones, either by removing the articular ends (Outram, 2001:402) or smashing the bones mid shaft both methods creating many shaft splinters (Outram, 2001:402).  Indeed, in archaeology “pig post-cranial bones are frequently relatively scarce or fragmented” (Albarella and Payne, 2005:589) because of this use.

On Skye in the Iron Age food resources would have been poor and from domestic settlements nearby marrow consumption has been found to be the norm, for example at Dun Ardtreck (Mackie, 2000). One suggestion for this is that the assemblage may represent a pig feast, particularly considering the predominantly single season kill evidence which may suggest a single, or closely-related, kill. If all individuals were killed at the same time there may have been such a surplus of meat for inhabitants that there was no desire to extract extra food from the bones. However, the other suggested “unusual” deposits in the cave, the two cows, both show evidence of marrow consumption and although these may have been deposited at a different time, it does suggest a difference in utilisation which is not easily explainable.

Figure 37: Diagram illustrating the points of disarticulation on the Zone 3 pigs as identified from working

From the location of cutmarks visible at the proximal and distal ends of the humerus, butchery appears to have occurred whilst the joints was still flexible and easy to disarticulate (Binford, 1981:94), suggesting the meat was fresh at the time of processing and providing further evidence for a close kill site.

It was recognised in the MNI analysis of the assemblage that the number of heads do not match the number of skeletons. The separation of head from body is common with pigs, giving access to the massive collar of meat and fat on the neck (Rowley-Conwy et al., 2002:80).  With the Zone 3 pigs the skulls have not only been removed, they have also been split sagitally down the medial line. This practice is highly unusual in archaeological assemblages, with no similar examples from contemporary Scottish sites, although Van Wijngaarden-Bakker (1990:171) and Binford (1981:109) do describe its occurrence in modern butchery techniques when processing hanging animals. This technique suggests the need for more substantial tools however than are evident from the cutmarks visible on the surviving High Pasture Cave bones (Binford, 1981:109) and there is little evidence of it having been used in antiquity (Smith, 1994:150).

At High Pasture Cave work on the mandibles shows a clear group of cutmarks around the Mandibluar hinge, to disarticulate the jaw from the cranium (Noe-Nygaard and Richter, 1990:181). There are no cutmarks suggesting the tongue was removed and there is no breakage of the tooth row to expose the large fat-filled cavity under the molars, which suggests that similar to the post-cranial bones there was no attempt to access the marrow of the pigs. The pig mandibles have however been deliberately separated into left/right sides, evidently by chopping on the lingual side to separate the jaws. The division of the skull and jaws of pigs while unusual for domestic assemblages is recognised in ritual assemblages across time and interpreted as a symbolic division into left and right of animals. It is unlikely in this assemblage to represent the splitting of the skulls to access brains and marrow, as there is no further evidence from the jaws to suggest marrow was desired.

Supporting the evidence for the pattern to represent symbolic division into sides is the division of the pig vertebrae into left and right parts down the saggital line.  This pattern cannot be explained by any butchery technique known from the past and there is little logical explanation for it. There are also numerous cutmarks on the ribs, not only on the expected lateral side, but also in the middle of ribs on the medial side. Why such a high amount of working was needed on this side of the ribs is unclear.

The symbolic division of animal carcasses into left and right sides has been noted from many societies, including Ancient Greece, where it is noted within Greek animal Sacrifices (Vernant, 1989:27) as representing symbolic division separating sacrifice parts for man and Gods. Within the Iron Age there are no other examples of this butchery technique in Britain, although in Europe similar splitting has been identified within a few funerary deposits, for example seen at the cemeteries of Allonville and Tartigny (Green, 1992:117-118) where it is thought to represent part of a symbolic funerary ritual.

There are few indications of burning on the bone. This lack of burning does not necessarily mean that the bones were not cooked, but that the bones were not roasted as might have been expected from a feast (Grigson, 1999:177), and may suggest alternative cooking methods such as boiling.

Section 2: Butchery in the other features of High Pasture Cave

1.  Zone 2 F.001 Cow

The Zone 2 cow consists of 158 cow bones, 81 of which have evidence for working (51.27%). There is no evidence for gnawing or burning on the bones, apart for some indication of heating on one astragali. The lack of gnawing or evidence of animal disturbance suggests that any breakage of the bones is due to human modification rather than post-depositional damage. With the excellent preservation of the animal and the presence of the vast majority of the skeletal elements, it is probable that the whole cow was deposited in the cave, including those bones which would usually be discarded for waste. This suggests that the cow was killed relatively close to the site of deposition similar to the pigs.

The Zone 2 cow is heavily fragmented, with each major bone being in multiple pieces, although the majority of the bones are present and can be refit to almost complete elements.  The form of these pieces suggests breakage to access marrow (Outram, 2001:402). The pieces have helical fractures and appear to have been struck with a substantial tool such as a cleaver. Often bones struck while fresh, as opposed to cooked, display this spiral and smooth morphology, whereas cooked bones display transverse fractures with rough edges (Alhaique, 1997:50), and it may be that these fragment shapes thus suggest that the bones were struck whilst fresh and uncooked (Alhaique, 1997:54).

The patterns of working on the Zone 2 cow confirm that the skeleton seems to have been divided by dismemberment before the animal was filleted to remove meat. The long bones then appear to have been shattered to access the marrow post-dismemberment. Many of them have been chopped at the epiphyses, for example the proximal epiphysis of the left Humerus has been completely removed and the shaft smashed.

Figure 41: Diagram of the points of dismemberment of the Zone 2 cow, determined from the working.

As well as the fracturing of the long bones to access marrow, the skull of the Zone 2 cow also exhibits working having been cleaved although whether this was to access the brain for nutrients is unclear.  This working is reminiscent of the Zone 3 pig skulls, where all the skulls, mandibles and vertebrae have been apparently deliberately divided into sides. There appears to be little mundane explanation for such large scale deliberate division within the pigs, although in cows the splitting of the skull alone may just illustrate processing to gain the brain for nutrients. In Iron Age Scotland however there are few examples of this practice or evidence that this was a common technique, and combined with the unusual division of the Zone 3 pigs it may be that the cows are also exhibiting this unusual working pattern.

The spine provides evidence that the head and neck were removed from the body with dismemberment at the 7th cervical vertebrae. This probably occurred in primary butchery (Binford 1981:110) and again suggests that the cow was not transported over a large distance as the head would have been discarded. The Pelvis shows evidence of deep chops close to the acetabulum and these are presumed to have been created when removing the femur in dismemberment. For the left Scapula only the joint remains and this may have been chopped from the blade in a similar process.

The Zone 2 cow pelvis shows clear working around the acetabulum of the pelvis. Similarly, on the Zone 5 cow the acetabulum are missing and it is possible that they were both removed in very similar processes to disarticulate the femur. The chopmarks on the pelvis of the Zone 2 cow are deep, suggesting a large cleaver-type instrument used on the bones, as well as fine cutmarks from a knife-like blade. The butchery evidence from the Zone 2 cow therefore suggests dismemberment for consumption, with consumption so complete that the marrow was utilised from the bone shafts. There appear to have been two types of tool used; a heavy “cleaver” and a finer “knife”. The most unusual feature of the working of the Zone 2 cow is the division of the skull along the medial line.

2.  Zone 5 Cow

The Zone 5 cow has evidence of working in the form of cutmarks and chopmarks on 75 of the 100 identifiable bones. The Zone 5 cow is heavily fragmented with each major element being broken into numerous pieces. The form of the breakage is suggestive of marrow access (Outram, 2001:402). The pieces have helical fractures and appear to have been struck with a substantial tool such as a cleaver. The radius also appears to have been broken mid-shaft, another common technique to access marrow (Bonnichsen in Binford, 1981:148). 

In contrast to the Zone 2 cow not all the elements of the Zone 5 cow skeleton are present. Many of the vertebrae appear to be missing along with the head and phalanges. This may indicate that the waste bones have been removed and discarded separately with only the meat-rich parts of the skeleton being deposited in the cave after the meat and marrow has been utilised. Particularly noticeable is the absence of the femur bones. It is unlikely that taphonomy could explain this pattern, with the femur being one of the larger and more robust bones. The top of the hind leg is one of the most meat-rich joints (Albarella and Serjeantson, 200:36) and this suggests that this prime joint may have been deliberately consumed and discarded elsewhere. From the pelvic evidence it is clear that much effort has gone into removing this joint, with major chopmarks removing the acetabulum, rather than dislocating the femur from the joint as is typical for femur removal (Binford, 1981:115).

From the working evidence, the bones appear to have been disarticulated before being smashed for marrow. This is shown, for example by the Tibia and Humeri, where chopmarks are clear in their proximal ends.  The cutmarks disarticulating the skeleton suggest disarticulation of all major bones. This is standard for a skeleton being utilised for meat, with the marrow access also indicating all resources were used.

Figure 48: Diagram illustrating the points of disarticulation on the Zone 5 cow

The Zone 5 cow appears to reflect the standard butchery of the Iron Age, i.e. butchered for consumption with the marrow also used. The absence of feet and head elements suggests that the waste products were disposed of separately, in contrast to the Zone 2 cow. The most unusual feature of the cow is the absence of the meat-rich femur elements, which suggests deliberate disposal of this most valued meat element elsewhere. The butchery appears similar to that of the Zone 2 cow, with the marrow access present as in the Zone 2 deposit, but not in the Zone 3 pigs. What vertebral evidence there is shows heavy working and sagittal splitting, similar to that seen in the Zone 3 pigs, the purpose of which remains unclear.

Section 3: Butchery in Contexts 002-010:

All faunal remains from Trench 1 contain working typical with butchery for domestic consumption. The greater fragmentation and burning suggests that they represent more normal domestic working than the context 001 unusual deposits, with heavy utilisation of the bones for marrow probably causing the greater fragmentation.

SUMMARY OF THE FEATURES OF HIGH PASTURE CAVE WARRANTING FURTHER INVESTIGATION

From the analysis of the High Pasture Cave bones it is apparent that there are features within the Context 001 faunal assemblage which suggests that it is more than simply the remnants of domestic consumption.

The Zone 3 Pig-Rich Assemblage

1. The c.90% dominance of pig in the assemblage is atypical compared to usual domestic assemblages where pig is the third most dominant species.

2. The bones are not smashed for marrow as is the norm for domestic assemblages and there is no evidence of burning.

3. There appears to have been deliberate division of all the skeletons into left and right parts, with division down the spine and skull centres, an unusual butchery technique.

4. There is a dichotomy between the number of skulls and number of post-cranial elements, suggesting a number of skulls were placed into the cave along with whole skeletons.

5. The ageing and biometry of the pigs suggests a predominantly Winter season of deposition, potentially indicating a single-deposit, or deposit at a similar time of year.

6. The pigs are probably domestic rather than wild and considering the environment in Skye at the time, this suggests a large amount of energy expended in keeping them.

7. The butchery evidence suggests they were killed fresh and so killed nearby.

The Two Individual Cow Deposits

1. Two individual cows have been deliberately placed into the cave; one in Bone Passage, one on a ledge high above the main streamway. Their bones have been smashed for marrow, but also one cow exhibits splitting of the skull similar to the Zone 3 pigs. There is no evidence of burning.

2. The cows differ in skeletal elements present. One is complete, the other is missing head and feet suggesting the waste from this may have been discarded elsewhere.

3. The butchery evidence suggests they were processed fresh and so killed nearby.

The Location

1. As well as the unusual aspects of the faunal assemblage, it must be remembered that the location is unique in itself. Few cave faunal assemblages have been excavated from Scotland and there are no parallels, particularly considering the evidence for access and deliberate sealing of the cave, rather than the cave just being used as an area of refuse disposal.

There is an apparent change from the earlier “domestic” deposits found within Trench 1 which may represent the use of the cave as a refuse area, to a deposit containing 3 very structured and unusual elements. Considering the location of the faunal remains within High Pasture Cave as well as these highly unusual deposits, it is impossible to conclude that the final deposit(s) at High Pasture Cave represent a typical domestic assemblage.

It is therefore important to consider further two aspects of the assemblage to attempt to interpret the archaeological context into which High Pasture Cave fits:

1. How the deposit relates to other Scottish assemblages, in particular whether there are any comparable sites.
2. The possible reasons behind the deposition, as suggested by other “unusual” deposits elsewhere.

The next section of this report will investigate these two research questions in depth, to try to understand more clearly the place of High Pasture Cave within British Archaeology.


Next entry: Specialist Report 2005 - Mammal Bone Assemblage (Interpretation & Comparison with other Assemblages)

Previous entry: Specialist Report 2005 - The Mammal Bone Assemblage (Methodology and Analysis of Bone by Context)