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Vindolanda's location, 3 km (2 mi) south of Hadrian's Wall, within the United Kingdom and the county of Northumberland.
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The Roman-era fort-village complex at Vindolanda in northern England, occupied from about A.D. 50 to A.D. 415, has yielded extensive well-preserved remains of the domestic dog, Canis familiaris. Herein, utilizing a novel combination of biostatistical techniques to identify parameters that best differentiate canids, we test the hypothesis that the i...
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... is a fort-village complex situated 3 km south of Hadrian's Wall in northern England (Figure 1). It was occupied almost continuously from about A.D. 50 to the fall of the Roman Empire toda vez que parece incorporan individuos que manifiestan una diversificación incipiente a partir de antecesores con aspecto de dingo. ...
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... simplest analytical technique we employed consists of selected ratios, called indexes (Harcourt, 1974) (Figure 9). We utilized Principal Component Analyses (PCA's; Figures 10, 11) primarily to predict parameters that best differentiate canid skulls and jaws, and then constructed De Grossi Mazzorin-Tagliacozzo Analyses (MTA's, see discussion below; Figures 12-20) which effectively display them. Harcourt's (1974) work, De Grossi Mazzorin & Tagliacozzo (2000) hit upon the very useful idea of plotting limb stoutness index against projected withers height. ...
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... the linear measurement is representative of other measures of size, and the ratio represents a readily-interpretable aspect of body shape or conformation. The MTA technique can thus be generalized, for example to produce easily-interpreted graphical representations of selected skull parameters (Figures 12-15). ...
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... use Harcourt's (1974) stoutness index (with MSD as numerator) for humerus, radius, and femur, but not for tibias or ulnas because the point selected for measurement of MSD on a bone with a continuously tapering shaft seems rather arbitrary. Therefore, for tibias we use a "stoutness index" (calculated as width across the proximal articular surface, Bp × 100) / bone length) ( Figure 17), while for ulnas we use the breadth across the base of the humeral articulation (Bpc × 100/ bone length) ( Figure 20). Utilizing a different numerator in calculating the tibia and ulna ratios yields different vertical scales, but the overall picture as shown by the MTA's is consistent with results for humerus, radius, and femur (Figures 16-20). ...
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... for tibias we use a "stoutness index" (calculated as width across the proximal articular surface, Bp × 100) / bone length) ( Figure 17), while for ulnas we use the breadth across the base of the humeral articulation (Bpc × 100/ bone length) ( Figure 20). Utilizing a different numerator in calculating the tibia and ulna ratios yields different vertical scales, but the overall picture as shown by the MTA's is consistent with results for humerus, radius, and femur (Figures 16-20). ...
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... the number of parameters measured on postcranial bones was small and were known beforehand to be diagnostic, MTA's were constructed without the use of PCA in the analyses of limb bones ( Figures 16-20 and see visual key, Figure 21). The very large dataset of modern domestic Raw size of skulls. ...
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... Index (Figure 9): The range represented by Vindolanda cranial and limb bone indexes is much less than those pertaining to domestic dogs (limb bone indexes are represented on the "y" axis in our MTA analyses, Figures 12-20). The range of skull indexes equals that of dingoes. ...
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... Components Analysis (PCA): The first principal component of the PCA on the four jaw parameters accounts for the great majority of the variation in the data (96.6%), and all the loadings are positive (all the biplot rays on Figure 10A are positive for PC1), making PC1 a rough allometric size measure for these canid types. Mandible depth (DP) is a good proxy for size, having a significant loading for PC1 but near-zero loading for PC2. ...
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... PC2 and PC3 accounted for comparable amounts of the remaining variation (1.6% and 1.1%, respectively). The biplot of PC2 and PC3 ( Figure 10B) shows a considerable contrast between jaw length (TL) and condyle size (CW) (their biplot rays point in nearly opposite directions). The average positions for the canid types (the centers of their 95% confidence ellipses) were reasonably well-separated along this "axis of contrast", even the two types of wolf (which were not distinguished on Fig- ure 10A). ...
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... biplot of PC2 and PC3 ( Figure 10B) shows a considerable contrast between jaw length (TL) and condyle size (CW) (their biplot rays point in nearly opposite directions). The average positions for the canid types (the centers of their 95% confidence ellipses) were reasonably well-separated along this "axis of contrast", even the two types of wolf (which were not distinguished on Fig- ure 10A). A jaw "shape" variation that contrasts between canid types is therefore likely to be expressed by a ratio of CW/TL. ...
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... jaw "shape" variation that contrasts between canid types is therefore likely to be expressed by a ratio of CW/TL. Since size is principally related to jaw depth, we use DP in an MTA plot with this ratio to discriminate canid types ( Figure 12). ...
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... first principal component of the PCA on 10 skull parameters accounts for the great majority of the variation (93.7%), and all the loadings are positive (all the biplot rays on Figure 11A are positive for PC1), making PC1 a rough allometric skull-size measure for these canid types generally. Zygomatic width (ZW) and palate length (PL) are the main measures of size, having significant loadings for PC1 but near-zero loadings for PC2; carnassial length (P4) might also be a workable general size measure, although its PC2 loading was somewhat larger. ...
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... width (ZW) and palate length (PL) are the main measures of size, having significant loadings for PC1 but near-zero loadings for PC2; carnassial length (P4) might also be a workable general size measure, although its PC2 loading was somewhat larger. The biplot ( Figure 11A) is similar to that for the jaws ( Figure 10A): foxes are smallskulled, dingoes about average, wolves large, and Vindolanda dogs much more morphologically diverse than natural wild-type canids. ...
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... width (ZW) and palate length (PL) are the main measures of size, having significant loadings for PC1 but near-zero loadings for PC2; carnassial length (P4) might also be a workable general size measure, although its PC2 loading was somewhat larger. The biplot ( Figure 11A) is similar to that for the jaws ( Figure 10A): foxes are smallskulled, dingoes about average, wolves large, and Vindolanda dogs much more morphologically diverse than natural wild-type canids. ...
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... 2 accounted for considerably more of the remaining variation (2.9% of the total) than PC3 (0.9%); it is possible that PC3 principally represents natural variation (differences in skull size and shape expected between twins, for example) or measurement error ( Figure 11B). The loadings of PC2 tend to be positive for parameters of the back of the skull (B, BP, RA) and negative for mouth parameters (PW, SW, perhaps P4) suggesting that brain-case shape contrasts with mouth shape. ...
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... conclusion that the fore-part and hind-part of the skull are fairly free to grow in different ways within domestic dogs (Drake & Klingenberg, 2010) may thus also be true for other canids. The biplot of PC2 and PC3 ( Figure 11B) shows a close relationship between palate width (PW) and snout width (SW); the greater loading of PW suggests that palate length tends to increase much faster than snout width. These two dimensions contrast with braincase dimensions, especially spine-articulation width (RA) (their biplot rays point in nearly opposite directions). ...
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... skull "shape" variation that contrasts between canid types is therefore likely to be expressed by a ratio of RA/PW. Since palate length is the better preserved of the two comparable measures of "size", we used PL in an MTA plot with this ratio to discriminate canids with differing relative neck strength ( Figure 13). The considerable contrast in allometry between SW and PW suggests that mouth shape may also alter significantly with mouth size; a ratio expressing the "pointedness" of the snout (SW/PW) was therefore plotted with mouth size (PL) as an MTA (Figure 14). ...
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... palate length is the better preserved of the two comparable measures of "size", we used PL in an MTA plot with this ratio to discriminate canids with differing relative neck strength ( Figure 13). The considerable contrast in allometry between SW and PW suggests that mouth shape may also alter significantly with mouth size; a ratio expressing the "pointedness" of the snout (SW/PW) was therefore plotted with mouth size (PL) as an MTA (Figure 14). De Grossi Mazzorin-Tagliacozzo Analysis (MTA): The bones of wolves are clearly differentiated by MTA from those of dogs, and the analysis suggests that wolf bones are generally rare or absent from Roman-era archaeological sites across Europe. ...
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... elements of foxes, however, are more problematic. The postcranial elements of dogs most likely to be confused with red fox are the tibia and femur; indeed, there is no guarantee that some bones reported in the literature as dogs, and treated as such in our analyses, do not actually belong to foxes (particularly likely in the case of Romano-British tibias, Figure 17). Forelimb elements overlap much less (Figures 18-20). ...
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... postcranial elements of dogs most likely to be confused with red fox are the tibia and femur; indeed, there is no guarantee that some bones reported in the literature as dogs, and treated as such in our analyses, do not actually belong to foxes (particularly likely in the case of Romano-British tibias, Figure 17). Forelimb elements overlap much less (Figures 18-20). Limb bones of foxes can be differentiated on the basis of detailed morphology from those of small dogs, and in a forthcoming paper we contrast fox postcranials from Vindolanda with small dogs of modern times and the Roman era. ...
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... plot for relative neck strength. Abbreviations as in Figure 2; symbol key as in Figure 12. ...
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... Vindolanda dogs are klinorhynchic ("down-snouted"), with a few falling into the 0 to 10º range. The MTA plot ( Figure 15) of cranial index vs. SA (called "β" by Nuss- baumer, 1982 and shows that the range in Vindolanda dog skulls is greater than in modern wolves, Pleistocene wolves, red foxes, or Australian dingoes; and that the range in modern dogs is in turn much greater than in the Vindolanda collection of skulls. ...
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... Grossi Mazzorin & Tagliacozzo (2000) built upon Harcourt's work by creating bivariate plots of limb stoutness index against projected withers height ("MT" analyses or MTA's). The resulting charts are easy to interpret and allow quick visual differentiation of long-bone material pertaining to dwarf, miniature, normal, gracile, and massive dogs (Figures 16-21). MTA shifts the emphasis away from heavy reliance upon skulls and jaws and is useful because archaeological cranial material is sometimes unavailable and often fragmentary, whereas limb bones often survive whole and in large numbers (Churcher, 1963;Bökönyi, 1984;Johnstone & Albarella, 2002;Grimm, 2007;Ayton, 2011). ...
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... stoutness computed as GL × 100/Bpc. Key to symbols as in Figure 16; anatomical abbreviations Figure 2. colleagues Phillips et al., 2009). Possibly because the results it produces are easier to interpret, Harcourt's (1974) indexing technique by contrast became standard. ...
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... measurements demonstrate this to be true 65% of the time, with modern domestic dogs, Australian dingoes, modern wolves, and some of the Vindolanda dogs all presenting exceptions. However, PCA led us to realize that P4 length alone correctly identifies dog vs. wolf over 90% of the time (Fig- ure 11; i.e., P4 length > 22 mm likely indicates a wolf). ...
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... technique for measuring klinorhynchy-airorhynchy in dog skulls is both novel and useful, and applied it to a dog from Iron Age Britain. We find airorhynchy ("up-snoutedness") to be an excellent character which occurs only in certain types of modern dogs (Figure 15). No wild or feral dog we have so far examined is airorhynchic, Visual key for the interpretation of Figures 15-19. ...
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... The index of width between the retro-articular processes (RA) vs. palate width (PW). We term this comparison "neck strength" ( Figure 13). (2) The index of snout width (SW) vs. palate length (PL), which we term "mouth shape" (Figure 14). ...
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... term this comparison "neck strength" ( Figure 13). (2) The index of snout width (SW) vs. palate length (PL), which we term "mouth shape" (Figure 14). The width between the retro-articular processes on the occiput is a measure of the strength of the attachment of the head to the neck and of the overall strength of the neck (Radinsky, 1981;Ellis et al., 2009). ...
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... width between the retro-articular processes on the occiput is a measure of the strength of the attachment of the head to the neck and of the overall strength of the neck (Radinsky, 1981;Ellis et al., 2009). In our MTA analysis (Figure 13), the small sample of Late Pleistocene wolves stands apart. They have long, wide palates -big "maws" (Fig- ure 14)-but necks that are noticeably weaker than modern wolves or many Vindolanda dogs, which may imply that they were primarily scavengers (carcasses don't wriggle). ...
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... our MTA analysis (Figure 13), the small sample of Late Pleistocene wolves stands apart. They have long, wide palates -big "maws" (Fig- ure 14)-but necks that are noticeably weaker than modern wolves or many Vindolanda dogs, which may imply that they were primarily scavengers (carcasses don't wriggle). At the opposite extreme, red foxes are the most likely of the groups studied to have neck attachments wider than their palates, not necessarily because their necks are strong but because their skulls are very narrow. ...
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... is more overlap in mouth shape ( Figure 14), with some Vindolanda dogs having rather foxlike mouths. The Vindolanda population and the Australian dingo overlap almost completely, so that in this character also the Vindolanda population appears to be a development out of a dingo-like ancestral morphology. ...
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... the same time, depth of jaw below the carnassial is a direct measure of the strength of the ramus, analogous to MSD for limb bones. MTA (Figure 12) separates wolves and foxes from dingoes and the Vindolanda dog population, which broadly overlap. Both of the latter trend toward broader condyles on jaws of only moderate stoutness. ...
