Was the English medieval goat genuinely rare? A new morphometric approach provides the answer

Salvagno, Lenny; Albarella, Umberto

doi:10.1007/s12520-019-00843-2

Was the English medieval goat genuinely rare? A new morphometric approach provides the answer

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Published: 01 June 2019

Volume 11, pages 5095–5132, (2019)
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Was the English medieval goat genuinely rare? A new morphometric approach provides the answer

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A Correction to this article was published on 15 August 2019

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Abstract

There are important gaps in the historical and archaeological evidence that have, so far, precluded us from reliably assessing the role of the goat in the English Middle Ages. This, in part, is the direct consequence of the absence of a methodology allowing the confident identification of sheep and goat bones. On the other hand, the fact that the goat has always been perceived as rare has led us to think that medieval goats did not deserve much attention. Thanks to a recently developed new morphometric approach, which allows taxonomic identifications to be based on more objective criteria and results to be scrutinised, we are provided with a new tool to re-assess the role that this species played in English medieval husbandry. This paper presents the results of the application of this new methodology on three archaeological medieval sheep/goat assemblages. Previous research suggested that the goat was not abundant in medieval England, but has also raised the possibility that this may be a consequence of an under-estimation by zooarchaeologists, due to identification difficulties. The basic outcome of our paper is to provide, for the first time, unambiguous evidence that the goat was genuinely uncommon. In the medieval archaeological record, sheep remains are overwhelmingly better represented than goat remains—all three case studies confirmed the pattern. Although these examples cannot be taken to represent the situation everywhere in the country, they provide clear-cut indication that the zoorchaeological interpretation of caprine remains from English medieval sites has so far been largely reliable. The three sites offer the opportunity to investigate different dimensions of the problem and to discuss the role of the goat in different contexts.

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Introduction

The goat has largely been neglected in British archaeology. This is partially due to the fact that this species appears to have been rare throughout the British history: finds of goat bones have always been numerically scanty compared to those of other main food domesticates (cattle, sheep and pig), and this situation has led us to think that this species did not deserve much attention. On the other hand, the methodological problems which affect our ability to distinguish between the bones of goat (Capra hircus) and sheep (Ovis aries) have also contributed to this attitude.^{Footnote 1}

With the availability of new data coming from recent urban archaeological investigations and the completion of some comprehensive reviews of the zooarchaeological records for medieval England (Albarella 2019; Holmes 2018; Stallibrass 1995)—which can be integrated with the written resources available for the period—a more comprehensive account of the English medieval goat has emerged.

The impression that one gains from the written sources for the Middle Ages is that the goat was mainly valued as a milk producer. As Fitzherbert (1534, p. 20) writes in his Book of Husbandry, “In the British Islands… it is chiefly for the supply of the domestic dairy that the goat can be regarded as of economic value”. Clearly, goat dairy products and, to a lesser extent, meat must have represented a useful additional contribution to the family economy; milk, cheese and butter surplus, along with (occasional) kids, would have been sold at the market. The meat of older goats was more likely to be consumed by the lower echelons of society, while kid meat was consumed by the wealthy, as evidenced by the accounts of several monasteries and noble households (Dyer 2004, 2006; Noddle 1994; Wilson 1973) as well as the archaeological evidence (Albarella and Davis 1996; Sykes 2006; Thomas 2005).

The Domesday Book, completed in 1086 (Darby 1977), contains details about the numbers of goats present in some English counties (Cambridgeshire, Cornwall, Devon, Dorset, Essex, Norfolk, Somerset and Suffolk). The impression gained is that goats, though far less common than sheep, were present in fairly high numbers (Albarella 1999; Dyer 1991, 2004; Hallam 1988). After the eleventh century, a drop in goat numbers is attested by manorial accounts and archival documents: goats become so scarcely mentioned that this species seems to have become almost completely absent (Dyer 2004; Woolgar 2006). Nevertheless, this situation does not reflect the complete reality, and in the western and northern regions of England, the goat continues to be present, though possibly in small numbers (Berkeley Castle accounts 1346 AD; Alkington accounts 1311–12 AD). From the written records, it is clear that in the late Middle Ages, goats were uncommon and were mainly confined to specific localities, to the west and north of the country (Dyer 2004).

The zooarchaeological records seem to agree—to a certain extent—with the written resources. Despite medieval archaeological sites in which goat bones have been found are scattered over many parts of the country, the number of remains belonging to goat is always extremely low compared to other domestic animals, and it is particularly low when compared to the most commonly found sheep bones. Whenever sheep and goat are mentioned in the same report, sheep is almost invariably and overwhelmingly the most common species (Albarella and Davis 1996). In addition, in continuity with the Roman period, goat remains in the Saxon period (fifth to eleventh centuries AD) appear to be more common in urban than rural sites (Albarella 2019). This is mainly due to accumulations of goat horncores in towns, which have been interpreted as the result of industrial activities, probably reflecting an interest in horn-working. In the later Middle Ages (eleventh to fifteenth centuries), the number of goat remains decreases further (Albarella 1997, 2003; Dyer 1991). Consistently with what was observed in previous periods, goat horncore deposits have mainly been found at urban sites located on the East Coast. Specific assemblages indicating the use of goat skins and horns are scantier in the southern and northern regions of England, where deposits of cattle horncores are more frequently reported (Holmes 2018; Stallibrass 1995).

Since horncores bear very clear morphological traits, allowing sheep and goat to be easily distinguished, the possibility needs to be considered that identification bias may have caused an over-representation of these elements. However, this bias would not explain why other fairly easily identifiable anatomical elements, such as metapodials, are almost completely absent from the English medieval archaeological record (Albarella 2003). In the post-Saxon period, the tanning industry had become predominant and the horn trade declined (Albarella 2003), which means that goats were more likely used for their skins than horns. According to Prummel (1978, 1982) and Schmid (1969), when the skins were prepared for further treatments, which eventually led to the final transformation of skin into leather, foot bones were retained. This raises the question of why these goat elements are usually missing from the archaeological record in England. The absence/under-representation of goat post-cranial bones points towards the hypothesis of a trade in goat skins with southern Europe, where this species was more abundant (Albarella 1999, 2003; Noddle 1994). With this in mind, the body part distribution anomaly reinforces the theory of long-distance trade, for which it would have been useful to eliminate as much weight as possible in order for the goods to be more easily stored and traded. It follows that the parts of the skin most suitable to be discarded were indeed the foot bones, which were not considered as valuable a source of working material as the horncores (Albarella 2003; Noddle 1994). A similar situation has been identified in other countries (Albarella 1999; Noddle 1994), such as the Netherlands (Prummel 1982), Germany (Anschutz 1966; Kühnhold 1971; Reichstein and Tiessen 1974; Schatz 1963) and Norway (Lie 1988).

The situation discussed above in relation to urban industrial sites cannot be applied to rural sites (or to urban sites outside industrialised areas), for which no evidence of goat horncore accumulations exists. Goat remains have been recorded at a few rural sites such as the twelfth- to early thirteenth-century Boteler’s Castle, Oversley, Warwickshire (Pinter-Bellows 1997) and the twelfth-century site of Walton, Aylesbury, Buckinghamshire (Noddle 1976). At both, a small number of goat bones were unearthed and concentrations of goat horncores were not found, suggesting that goat was only occasionally used and was husbanded rather than used in industrial activities. Unfortunately, the western and more rural areas of the country remain, to this day, insufficiently documented (Albarella 2019) preventing us from undertaking an in-depth study of regional patterns.

Through an exploration of the zooarchaeological literature, a further problem arises. Due to the perceived rarity of the goat and the well-known difficulty of distinguishing between sheep and goat bones, an attempt to separate these two taxa has not always been made by zooarchaeologists. In the cases in which discrimination is carried out, the numbers related to the goat are so low that raw data are often omitted and further information excluded from the report. In many cases, attempts to differentiate have not been carried out at all, so that the two taxa appear combined in the joint category of ‘sheep/goat’. Sometimes, zooarchaeologists take for granted the absence of the goat and all remains are attributed to sheep. Such an attitude limits the possibility of accurately assessing the presence of the goat and to quantify the relative proportions of sheep and goat.

To sum up, there are still important gaps in the historical and archaeological evidence that preclude us from reliably assessing the role of the goat in the English Middle Ages. These gaps are in part a consequence of the absence of a transparent methodology, which allows to scrutinise the reliability of the identification of sheep and goat bones. Morphological criteria have existed in the literature for several decades (e.g. Boessneck 1969; Cornevin and Lesbre 1891; Hildebrand 1955; Kratochvíl 1969), but they tend to rely on the skill, experience and attitude of the analyst and are, therefore, rather subjective. Thanks to a recently developed new methodology (Salvagno and Albarella 2017)—which combines biometrical and morphological approaches—a step towards solving the sheep and goat identification issue has been made. Such methodology, which is based on measurements, thus allowing taxonomic identifications to be based on more objective criteria, represents the ideal tool to use in order to start a re-assessment of the role of the goat in English medieval husbandry.

Given these premises, this paper intends to:

1.
Test the extent to which the new methodology, designed on modern comparative material (Salvagno and Albarella 2017), can be effectively applied to archaeological material.
2.
Present the results from the study of three sheep and goat medieval assemblages. These assemblages have the potential to:
1. (a)
  Clarify if the scarcity of goat remains is due to an under-estimation of this species by zooarchaeologists, or is, indeed, genuine.
2. (b)
  Verify whether goats were mainly represented by horncores or if other anatomical elements were present.
3.
Lay the basis for a more objective re-assessment of the role that the goat played in medieval English husbandry.

Materials and methods

Three medieval sheep and goat assemblages from King’s Lynn (Norfolk), Flaxengate (Lincoln) and Woolmonger/Kingswell Street (Northampton) were selected as the most suitable and were re-analysed for the purpose of this study (Fig. 1).

King’s Lynn (KL) (1050–1800 AD)

Situated in the county of Norfolk in the east of England, this port site is located on an important area of convergence of roads, rivers and sea routes. From the thirteenth century onwards, it reached its peak as a centre of trade, maintaining contacts with France, the Low Countries and Scandinavia along with a lively inland commerce (Parker 1971). The archaeological investigations, carried out between 1963 and 1970, revealed a long time span of occupation which goes from the Late Saxon (c. 1050) to the post-medieval period (c. 1800) (Clarke and Carter 1977). The animal bone assemblage (Noddle 1976, 1977) is unusual because of the reported goat abundance. Noddle (Noddle 1977, p. 397) emphasises that “the considerable population of goats in King’s Lynn is by no means unique”—a surprising statement in view of the evidence from other sites (Albarella 1999).

Flaxengate in Lincoln (FL) (late eleventh; late fourteen to middle sixteenth century AD)

Located in the county of Lincolnshire, Lincoln was first occupied in the Iron Age, then by the Romans, and became a nucleated village in the ninth century. After the Norman Conquest (1066 AD), the city became one of the largest urban centres in the East Midlands (Jones 2003). The excavations (1945–1948 and 1972–1976) revealed a chronology ranging from the Late Saxon period (c. 870/80–900) to the post-medieval period (late seventeenth/early eighteenth to nineteenth century) (O’Connor 1982). The analysis of the animal bones, originally carried out by O’Connor (1982), revealed a complete absence of goat remains. Only contexts representatives of the medieval and early post-medieval periods (from the eleventh to early–middle sixteenth century) were selected.

Woolmonger/Kingswell Street in Northampton (WKS) (1000–1550 AD)

This site is located in central-eastern England and has always played an important strategic role. Its history goes as far back as the Iron Age. It then became a Roman settlement and then probably an Anglo-Saxon centre. Further growth of the town occurred in the following period (Brown 2008; Williams 1979). Northampton reached its peak in the second half of the twelfth century, when it is reported as the sixth most prosperous town in the kingdom (Brown 2008; Williams 1979). The decline began in the thirteenth century and became evident by the fourteenth century. The archaeological investigations (1972–1974; 1981–1987; 1994 and 2005) revealed a chronology which spans from the Late Saxon (AD 1000–1100) to the late medieval/early post-medieval period (AD 1400–1550). Armitage (1998–1999, 2008), who initially studied the animal bones, published the results in the form of very concise reports where all caprine remains are reported as sheep, with no goat or sheep/goat categories mentioned.

More specifically, these sites were selected because:

In the case of KL, the results of the zooarchaeological analysis represent an anomaly, which called for verification.
The other two sites are also urban, but located inland and in different regions from KL; thus, they represent different geographic scenarios, which are worth comparing.
All three assemblages provided substantial bone material of reasonably refined chronologies, for which the status of the goat had not been fully clarified given the cursory nature of the methodological explanation concerning the approach to sheep/goat distinction.

All the animal bone assemblages included in this study are publicly deposited and accessible by other researchers. Permission to study the material was given by the institutions mentioned below, through a loan for research agreement. The animal bone material from King’s Lynn is currently held at the Lynn Museum storage at Gressenhall Farm and Workhouse Museum in Norfolk. The assemblage from Flaxengate is currently stored at The Collection: Art and Archaeology in Lincolnshire in Lincoln, while the assemblage from Woolmonger/Kingswell Street is stored at the Northampton Museum and Art Gallery in Northampton.

As the main aim of this study is to re-examine these medieval sheep/goat assemblages in order to assess with a more objective methodology the presence of goat remains, the data for each individual site have been considered in toto, regardless of their chronology.

The methodology used is based on a combination of the traditional macro-morphological approach with a new morphometric approach. First, identification to species level was undertaken using selected morphological traits from previous literature on the topic (Supplementary material 1). The categories used for the morphological identification were as follows:

Sheep—classified as such if more than 50% of the morphological traits pointed towards sheep
Goat—classified as such if more than 50% of the morphological traits pointed towards goat
Sheep/goat—classified as such if only a minority of traits could be attributed to one of the two species

The morphometric approach has been developed by the authors (Salvagno and Albarella 2017), and it is based on the use of biometrical indices (BI) and linear discriminant analysis (LDA) in order to describe metrically the morphology of selected bones. Measurements, approximated to the tenth of a millimetre, were taken whenever possible with digital callipers.

The analysis was carried out in this order:

A quantification according to body parts, so that the number of morphologically identified specimens and body parts represented at each archaeological site could be better evaluated
A shape analysis through the use of BI in order to verify whether the morphological identification could be confirmed by biometry
LDA in order to:
- Gain further insight into the possible presence of goats in the samples
- Verify whether the identifications carried out through the use of the morphological traits could be confirmed or rejected by the LDA
- See if some of the sheep/goat specimens (i.e. those which could not be attributed to one of the two species because of the lack of strong morphological diagnostic traits) could be attributed on the basis of a larger set of measurements than used for BI

LDA or direct option (Tabachnick and Fidell 2007, p. 395) was preferred to the stepwise method (Tabachnick and Fidell 2007, p. 396) because all the variables are included together at once during the analysis; with the stepwise method, they are inserted by the program which chooses, according to different statistical criteria, which variables are the most effective (Tabachnick and Fidell 2007, pp. 395–396). The problem with this kind of approach is that the order of entry of the variables may be dependent on differences in the relationship among predictors that are irrelevant, so that they do not reflect population differences (Tabachnick and Fidell 2007, p. 395). In addition, there is no control over the variable selection process. As the methodology used in this study has been designed for the analysis of archaeological material, there are some measurements that are chosen because they are more likely to be taken on fragmented specimens than others (i.e. GL is rarely taken, unless you have a complete bone). For these reasons, a ‘manual’ control of the variables has been preferred (LDA).

As the main aim of the study is to look at the morphology of the bones without taking into consideration size, which can sometimes cloud the results, a method of standardisation, following the protocol used by Davis (1983), was applied to the raw data. This method consists of expressing each measurement of each bone as a fraction of the whole (i.e. individual measurements were divided by the total for that bone and multiplied by 100; Davis 1983, p. 523). The same standardisation method has been applied to both the modern and archaeological data presented in this study. To have a framework of reference for the expected distribution patterns of both species, data from modern sheep and goat reference collections (Salvagno and Albarella 2017) have been used as a baseline for the biometrical analyses (BI and LDA). All the statistical analyses were conducted with SPSS statistics program.

Results

Quantification according to body parts

Table 1 shows the number of morphologically identified sheep and goat specimens for each archaeological assemblage. At all three sites, some goat remains have been identified, but sheep is far more numerous. While for the sheep all body parts are present, the goat is mainly represented by horncores, and post-cranial bones are rare. KL represents a very clear example of this pattern: horncores are the only anatomical elements in which goat outnumbers sheep. If the horncores are included in the count, the sheep:goat ratio at the sites are 11:1 at KL, 283:1 at FL and 51:1 at WKS. The sheep and goat ratio drastically changes if the horncores are excluded: 163:1 at KL, 819:0 at FL and 76:1 at WKS. Clearly, horncores heavily influence the sheep:goat ratio. This preliminary morphological evidence therefore confirms the known patterns for sheep and goat during the medieval and early post-medieval periods: sheep remains are far more numerous than goat remains and, when the goat is present, it is mainly represented by horncores. The problem, however, remains that this evidence is based on trust—namely the correctness of our identifications, relying on rather subjective criteria.

Table 1 NISP (number of identified specimens) for each of the three analysed sites

Full size table

Shape analysis: biometrical indices

Horncores

Figure 2 shows the combinations of measurements taken on the horncores for all three sites. On the horizontal axis, there is the ratio between E and F (length of the horncore = E; the length of its outer curvature = F), and on the vertical axis, the ratio between A and F (maximum diameter = A). At all sites, the separation between sheep and goat horncores is clearly visible with a minimum amount of overlap: archaeological sheep tend to plot among the modern sheep group, while the archaeological goat falls among modern goats. The fact that the E/F ratio is higher in goats while the A/F ratio is higher in sheep mirrors the differences in shape of this element between the two species (Clutton-Brock et al. 1990; Schmid 1972). No extreme outliers are present. However, a morphological identified sheep specimen (in KL) falls clearly among the archaeological and modern goat group: this could indeed represent a morphological misidentification. The specimens falling in the small area of overlap are not too far from the other archaeological specimens attributed to the same species and they are consistent with the distribution patterns of the modern material (polygons); thus, the morphological identification looks to be largely reliable. Overall, in the case of the horncores, biometrical data support morphological identifications.

Scapula

Figure 3 shows the ratios of measurements taken on the archaeological scapulae, which are meant to describe the difference in shape of the processus articularis in the two species. On the horizontal axis, there is the ratio between GLP (greatest length of the processus articularis) and LG (length of the glenoid cavity), while on the vertical axis, GLP/BG is plotted (BG being the breadth of the glenoid cavity).

The archaeological goats (despite their small number, only two from KL) have a lower score on the vertical axis, reflecting the more circular shape of the glenoid cavity in this species (Boessneck 1969; Prummel and Friesch 1986). One of the goat specimens falls in the area of overlap between the modern sheep and goat groups. The other goat specimen falls outside the range of the modern goats but follows the same distribution pattern, showing very strong goat traits. The identification as goat of these two archaeological specimens is further confirmed by the fact that, when other measurements are used (Fig. 4), both specimens fall among the modern goat group or in the area of overlap between modern sheep and goats. All archaeological sheep fall either among the sheep modern group or in the area of overlap, supporting their identification. Some, despite following the same distribution pattern of the modern sheep group, fall outside the sheep polygon showing strong sheep traits.

A number of undefined sheep/goat specimens are present. At KL as well as at FL and WKS, the sheep/goat specimens largely fall either in the area of overlap between the modern sheep and goat groups, or in the area where the modern sheep gather. Since they seem to plot more towards the centre of the sheep distribution, they are likely to be sheep. The only exception is the sheep/goat specimen falling at the bottom of the plot at WKS (Fig. 3). This specimen is substantially distinct from the sheep archaeological specimens, and it seems to be more consistent with the goat pattern of distribution.

In Fig. 4 , different ratios are presented: on the horizontal axis, there is the ratio between ASG (shortest distance from the base of the spine to the edge of the glenoid cavity) and SLC (smallest length of the collum scapulae), while on the vertical axis, GLP is divided by BG. These combinations should be able to describe the difference in the shape of the glenoid cavity and the collum scapulae between the two species. On the graph, the thinner, more slender collum scapulae of the goat demonstrates a greater distance between the glenoid cavity and the base of the spine (lower GLP/BG scores and higher ASG/SLC), while for sheep, the distance between the glenoid cavity and the base of the spine is shorter and the collum scapulae is thicker and stouter (Boessneck 1969).

The only archaeological goats identified are from KL, and as Fig. 4 shows, their morphological identification is consistent with the biometric values. Archaeological sheep at all three sites largely fall in the area of the graph with their modern counterparts. Since they follow the distribution of the modern sheep, their morphological identification should not be questioned. A few archaeological sheep specimens at KL and WKS fall outside the modern sheep group showing strong sheep traits.

Unidentified sheep/goat specimens at all three sites fall either in the modern sheep group or in the area of overlap. With the exception of the WKS specimen mentioned above, these specimens are likely to be sheep rather than goats as they plot more towards the centre of the sheep distribution. Their weakly expressed morphological characteristics—which have led to their identification as sheep/goat—are mirrored by the biometrical data.

Humerus

Figure 5 compares BE/HTC (BE = breadth of the capitulum; HTC = minimum diameter of the trochlea constriction) and BE/BT (BT = medio-lateral breadth of the trochlea) ratios, which describe the differences in the distal trochlea of the humerus. Goats have an overall more medio-laterally elongated trochlea than sheep (Boessneck 1969), resulting in higher scores for both indices. Only one goat distal humerus has been found at KL, and this specimen is borderline between the goat and the sheep modern groups; as such, its identification is retained. The archaeological sheep all fall either in the area of overlap of the modern groups or among the modern sheep; as such, they are consistent with their morphological identifications. Some sheep specimens at WKS show strong sheep traits, as they still follow the modern sheep distribution but plot away from the core of the modern cluster (see lower part of the distribution).

Several sheep/goat specimens are present at the three sites, and they mostly fall in the area of overlap between the two modern groups. As the amount of overlap is significant—preventing us from clearly identifying the centres of distribution for the two species—biometry in this case cannot assist in assigning them to species level. The only exception is one of the sheep/goat specimens at KL as it clearly plots among the modern sheep, and as such, it is more likely to be from a sheep.

Figure 6 shows BEI/BT plotted against BEI/Bd (BEl = breadth of the epicondyle lateralis; Bd = breadth of the distal end). This combination describes the different shapes in the epicondyle lateralis in the two species (Boessneck 1969; Helmer and Rocheteau 1994; Prummel and Friesch 1986). The only identified goat at KL plots in the area of overlap, which is not inconsistent with its morphological identification. The sheep at all sites either occupy the area of overlap of the two modern samples or fall among the modern sheep group. At all sites, some sheep specimens present strong sheep traits, plotting outside the sheep cluster (upper part of the distribution).

One sheep/goat specimen from FL falls in the area of overlap and another from WKS just outside it, in the modern sheep group. However, since the overlap is significant and centres of distributions are hard to identify, the identification of both remains uncertain. Two sheep/goat specimens at KL fall very clearly among the modern goat group, but considering the distribution pattern of the archaeological sample, and the fact that these two specimens fall among the sheep in Fig. 5, the evidence is not strong enough to justify a re-attribution.

Radius

Figure 7 shows the ratio between BFp/Bp (BFp = breadth of the facies articularis proximalis; Bp = greatest breadth of the proximal end) on the horizontal axis and Dp (depth of the proximal end) on the vertical axis. This combination describes the overall differences in the shape of the proximal articulation of the radius (Boessneck 1969; Prummel and Friesch 1986; Zeder and Lapham 2010).

Only one goat radius has been identified at KL and it falls indeed within the goat group. Most of the archaeological sheep gather in the area where only modern sheep plot or in the area of overlap. Nevertheless, some archaeological sheep at KL plot clearly among the modern goat group. This phenomenon was not observed on the modern material, and the inconsistency of distribution between modern and archaeological sample could be due to the fact that the proximal radius is known to change with age as, through time, it undergoes post-fusional growth (cf. Payne and Bull 1988 for pigs). In the modern sample, the age factor was controlled, while in the archaeological material, the same factor is unknown. As a consequence, different age classes—compared to the modern material—could potentially be present in the archaeological material, causing inconsistency. Thus, the use of these measurements to distinguish the two species in an archaeological assemblage needs to be taken with caution as the effectiveness of the BI may vary according to the population under study. Potentially, they can still be useful, as they were very successful in the separation of sheep and goats in the modern material, but they may not help in all cases, as shown for our three sites.

The sheep/goat specimens fall mainly in the area of overlap, so that they cannot be attributed to one of the two species. One sheep/goat specimen from FL, however, plots clearly among the goat modern group far from the archaeological sheep cluster; for this specimen, an identification as ‘goat’ appears to be reasonable, as it represents a clear outlier to the sheep cluster, but we must consider the caveat mentioned above.

Ulna

Figure 8 shows biometrical indices (BPC = breadth of the coronoid process; DPA = depth of the processus anconaeus; SDO = smallest depth of the olecranon) which describe the shape of the lateral coronoid process in the ulna; this is in fact more laterally elongated in goats than in sheep which is why goats have higher values in both ratios (Boessneck 1969; Prummel and Friesch 1986). No goat ulnae have been identified. Most of the archaeological sheep fall in the area of overlap or among the modern sheep group. This is potentially consistent with their morphological identifications. Several archaeological sheep specimens fall in the bottom left corner of the graph showing very strong sheep traits.

If the sheep/goat specimens are considered, it can be seen that some fall in the area of overlap between the two modern groups; thus, biometry cannot determine their identification even though they seem closer to the sheep centre of distribution than the goat centre. Several other sheep/goat specimens fall clearly among the sheep group or even outside it, showing very strong sheep traits (see FL).

Metapodials

Figure 9 presents the ratios taken on the distal articulation of the metacarpals. On the horizontal axis, there is the ratio between measurement 1 (1 = diameter of the medial trochlea) and a (a = width of the medial condyle), while on the vertical axis, there is a ratio between measurements 1 and 2 (2 = verticillus of the medial condyle). These combinations describe the morphological difference between the peripheral part of the trochlear condyles which is larger in sheep than goat (Boessneck 1969; Zeder and Lapham 2010). No goat archaeological metacarpals have been identified. Most of the archaeological sheep fall in the area occupied by the modern sheep with only a few borderline specimens. These archaeological sheep (at FL and WKS) fall very close to the modern sheep cluster and seem to be consistent with the sheep distribution pattern.

Two morphologically unidentified sheep/goat specimens from FL fall among the modern sheep cluster and seem to gather around the modern sheep centre of distribution; thus, they are likely to be sheep.

Figure 10 shows a different combination of measurements: BFd and GL (BFd = greatest breadth of the distal end; GL = greatest length) on the horizontal axis and SD (SD = smallest width of the shaft) and GL on the vertical. These indices describe the overall aspect of the bone which is slender in sheep and stouter in goat (Boessneck 1969). No archaeological goat metacarpals have been found. All the archaeological sheep, identified as such on the basis of their morphological features, fall among the modern sheep cluster or in the area of overlap between the two modern groups. As a consequence, their identification seems to be sound.

The same combination of measurements used for the metacarpals were adopted for the metatarsals. Figure 11 describes, as Fig. 9 does for the metacarpals, the morphological differences between the peripheral part of the trochlear condyles (Boessneck 1969; Helmer and Rocheteau 1994). There is much more overlap between the modern groups, indicating that the metatarsals are less effective than the metacarpals for separating between sheep and goat, as already suggested by Payne (1969). Only two goat metatarsals are present and both come from WKS. Both specimens fall in the area of overlap, and therefore, there is no reason to question their identifications. At all sites, most of the archaeological sheep fall in the modern sheep cluster, confirming their identification. A few archaeological sheep are borderline (at both KL and FL): they fall among the modern goat cluster but not far from the sheep group; for these specimens, further verification is required. Other archaeological sheep from FL show very marked sheep traits as they fall outside the modern sheep group but follow the same pattern.

Two unidentified sheep/goat specimens are present at FL: one falls in the area of overlap and the other outside both modern groups. In this case, biometry cannot assist in their identifications.

Figure 12 (BFd and GL plotted against SD and GL) describes the overall difference in shape of the metatarsal (Boessneck 1969). Only one archaeological goat has been morphologically identified, from WKS; it plots in the area of overlap between the two modern groups and is therefore potentially consistent with the original identification. At all three sites, the archaeological sheep mostly fall in the area where the modern sheep are or in the area of overlap, consistently with their morphological identifications. At KL, a specimen identified as sheep plots as an outlier, showing pronounced goat characters. However, in Fig. 11, the specimen does not appear as an outlier. Given the inconsistency of the evidence, it is safer to regard that specimen of uncertain attribution.

Only one sheep/goat specimen is present (at FL); this specimen plots in the area of overlap, but since it stands very close to the archaeological (and modern) sheep centre of distribution, it is likely to be a sheep.

Tibia

Figure 13 shows the ratios taken on the distal articulation of the tibia (Bd = breadth of distal end; Dda = depth of the medial side; Ddb = depth of the lateral side) which are supposed to describe the overall shape of the distal end of this bone (trapezium-like shape in sheep and rectangular-like shape in goats) (Kratochvíl 1969). Only one archaeological goat has been identified at WKS: this specimen falls in the area of overlap between the two modern groups and there is thus no reason to question its identification. At all sites, the archaeological sheep fall among the modern sheep or in the area of overlap. A few archaeological sheep fall among the modern goat group, but as they are not too far from the archaeological sheep cluster and they seem to follow the sheep centre of distribution, the evidence is not strong enough to re-consider their identification. However, identification must be questioned for two sheep specimens—one from KL and the other from WKS—that fall more distantly from the archaeological sheep cluster (low on the vertical axis).

Sheep/goat specimens are present at all three sites: most fall clearly among the modern sheep; thus, they are likely to belong to this species. Some are in the area of overlap, though they seem to be more consistent with the sheep distribution pattern. Two specimens from WKS, however, look dubious: they fall far from the modern sheep cluster and more towards the modern goat group. One even falls outside the goat cluster, showing very marked goat traits. For these specimens, identification must be reconsidered.

Astragalus

Figure 14 shows the ratio between H (height of the central constriction) and Dl (greatest depth of the lateral half) on the horizontal axis and between Bd (breadth of the distal end) and GLl (greatest length of the lateral half) on the vertical axis for the astragalus. These combinations should be able to translate: (A) the depth of the sulcus at the middle of the trochlea which is usually deeper in sheep than in goat (Boessneck 1969); (B) the presence of an articular ridge which projects more in goat than in sheep (expressed by measurement Dl) (Boessneck 1969; Zeder and Lapham 2010); and (C) the ratio Bd/GLl also reflects the overall shape of the bone which is more robust in sheep than in goat (Boessneck 1969).

No archaeological goat astragali have been identified. Most of the archaeological sheep fall either among the modern sheep or in the area of overlap. There are a few archaeological sheep specimens that can be considered borderline (at KL and FL): they fall among the modern goats, but they are quite close to the other archaeological sheep; thus, the evidence is not strong enough for their morphological identification to be questioned. An archaeological sheep at KL falls well outside the modern sheep cluster showing strong sheep traits. The only sheep/goat specimens (FL) fall in the area of overlap, therefore remaining ambiguous.

Figure 15 presents the ratio between Bd and Dl on the horizontal axis and the ratio between Dl and GLl on the vertical axis. The separation between the two species is mainly determined by Dl/GLl. The higher Dl/GLl scores in sheep mirror the more robust shape (wider in relation to the height) of the bone of this species compared to the goat. No archaeological goats have been identified. Archaeological sheep all fall among the modern sheep or in the area of overlap, confirming their morphological identification. Two sheep specimens at KL and FL show very strong sheep traits.

Two sheep/goat specimens are present at FL: they both fall in the area of overlap; thus, their identification cannot be established. Nevertheless, it must be said that they seem more consistent with the sheep distribution pattern.

Calcaneum

Figure 16 shows measurements c (length of the articular facet of the os malleolare) and d (length taken from the articular facet of the os malleolare to the end of the articulation-free part of the process) plotted against ratio between c and the B (the breath of the articular facet of the os malleolare). These combinations mirror (A) the fact that the length of the articular facet for the os malleolare on the lateral process is greater than half of the entire process in sheep while in goat it is smaller (Boessneck 1969; Zeder and Lapham 2010); and (B) the difference between the articular facet of the os malleolare which in sheep is longer and narrower, whereas the same articular facet in goat is wider and shorter (Boessneck 1969; Zeder and Lapham 2010). Once again, no archaeological goat astragali have been identified. Most of the archaeological sheep fall among the modern sheep cluster or in the area of overlap, as such there is no ground to question their morphological identifications. At all sites, there are some archaeological sheep which follow the sheep pattern but plot outside the modern sheep cluster; these specimens have very strong sheep traits.

Very few specimens have been identified as sheep/goat, and they fall in the area of overlap between the two modern groups; as a consequence, biometry cannot help with the identification, even though they seem more consistent with the sheep pattern than the goat.

Figure 17 shows a different combination of measurements: DS (depth of the substentaculum tali) is plotted against c on the horizontal axis, while on the vertical axis, there is the ratio between c and d. The outcome is consistent with what shown in Fig. 16. All the archaeological sheep fall among the modern sheep or in the area of overlap, confirming their identification. One archaeological sheep at KL shows strong sheep traits, plotting outside the sheep group but following the same pattern.

The few sheep/goat specimens fall in the area of overlap between the two modern species. They seem to be consistent with the sheep group, and as such, they are very likely to be sheep.

Results are confirmed also when using a different ratio (DS/c and c/B; Fig. 18): the archaeological sheep plot among the modern sheep cluster or in the area of overlap. Some specimens plot outside the sheep group showing strong sheep traits.

The sheep/goat specimens are very few and they mainly fall in the overlapping area. Nevertheless, they seem to be more consistent with the sheep distribution than the goat pattern.

Third phalanx

Figure 19 shows a combination of measurements (MBS and DLS) which mirrors the difference in the shape of the sole in the two species (Boessneck 1969). Despite the sample size being very small, the archaeological sheep convincingly follow the modern sheep pattern falling, either among the modern sheep group or in the area of overlap.

Linear discriminant analysis

LDA has been applied to the archaeological assemblages in order to have further insights into the distinction between sheep and goat and also to test if the same successful outcome we had with the modern material (Salvagno and Albarella 2017) could be obtained on fragmented archaeological assemblages. In this instance, LDA is used as a predicting tool. The program attributes an individual score to each of the new archaeological cases. This score represents the distance of that individual specimen from the group centroid value (i.e. group means of the predictor variables; Field 2009, p. 620) calculated for each modern group. As a consequence, the program itself attributes to species level (prediction) the archaeological specimens on the basis of their individual scores; the group to which the new cases will be attributed is the one from which their distance is smallest (Burns and Burns 2008).

LDA, as it evaluates all metric variables at the same time, has the potential to support or contradict the identifications based on the morphological approach, and it represents an additional aid for attributing the unidentified specimens to species level.

Results for all three sites are presented on an element by element basis. The diagrams show, on the horizontal axis, the individual discriminant score attributed by the LDA to each archaeological specimen and, on the vertical axis, the species attributions assigned by the program. The only possible attributions were goat, identified by the number 1, and sheep identified by number 2 (vertical axis). The vertical lines on the graph represent the group centroids for each species.