Age Determination
The most fundamental measure of adaptation in any human community is survival.  For ancient populations, inferences are made about survival from patterns of morbidity and mortality.  The success of an individual's 'adjustment', both social and biological, is reflected in their ability to survive and reproduce.  An age profile of the St. Stephen's skeletal collection is thus an important component for understanding community composition.

Click on the image of choice to learn more about each age determination method (under construction).

L-R:   Top row - pubic symphysis morphology, auricular surface morphology, age-related size distribution, tooth wear, epiphyseal closure, dental eruption patterns.

INTRODUCTION:  During the period of growth and development, age estimation is usually quite precise; however, with the cessation of growth and eruption of the permanent dentition, assessment of age becomes more difficult, relying on evidence of degenerative processes.  Nevertheless, with multiple sites of analysis available for a single individual, determination of age-at-death using intersecting lines of evidence can be highly accurate for adults (1).   For this collection, an age profile was established using two aspects of pelvic morphology and consistency of results compared across the group.

Pubic Symphysis:   Morphological changes of the articular surfaces of the innominate provided the best postcranial age indicators for the St. Stephen's adults.  Variation in the face of the pubic symphysis, the anterior-most point of articulation between the two innominates in the pelvic girdle, is a common region analyzed for age determination. Todd outlined a 10-stage method for assessing this surface, based on a large sample of male innominates (2).  Changes in the symphyseal surface over time proceed in a predictable pattern from a heavily contoured face, to one delimited by a rim in the mid 30s, to a surface marked by increasing porosity after 40 years.  Analysis by Meindl and coworkers has shown the Todd method to be the most accurate of the pubic symphyseal methods available (3).

Pubic symphysis ages for all specimens (n=54) are listed in Table 1, with the specific Todd age categories expanded to decades in the final column of the table (4).   Several authors have argued the importance of using broad age categories in paleodemographic contexts, stating the increased accuracy in analysis given the limits of adult age estimation (5).

No significant difference was found between the left and right pubic symphyses (p=0.51) using the Kolmogorov- Smirnov two sample test.  Thus, to avoid possible duplication of individuals, only the right innominate (n=27) was used for statistical analyses.  The median age for the adults was decade 4 or 30-39 years, with the largest number of individuals falling in the 6th (50+ years) decade.  The Todd method can not differentiate age after 50 years, thus numerous older individuals were merged by default in this encompassing age category.

Auricular Surface:   The site of articulation of the innominate with the sacrum, known as the auricular surface, was the second pelvic age indicator employed.  The method was developed by Lovejoy and co-workers, using a portion of the innominate often better-preserved in the depositional context than the pubic symphysis (6).   This was certainly true for the St. Stephenâs collection, where 87 auricular surfaces versus 54 pubic symphyses were found.  In a system reminiscent of Toddâs pubic symphysis method, the auricular surface technique compares changes in billowing, granulation, porosity, and transverse organization on the face of the innominateâs articulation with the sacrum (7).    It also permits a bit more finesse at aging older individuals, with  50-60 year and 60+ year age categories.

Table 2 reflects auricular surface ages (8) for all specimens (n=87). Again, no significant difference (p=0.30) was found between the left and right innominates.  Thus, for consistency of comparison to the pubic symphysis data, the right side (n=41) was selected for statistical comparison.  As was true of the pubic symphysis, the median age category was the 4th decade (30-39 years), though the highest percentage of individuals clustered in the 5th (40-49 year) age group.

Comparison of the percentage of individuals in each age category for the two features allowed a test of agreement between methods. Graph 1 (below) illustrates the age profiles superimposed.  No significant difference was found between the two methods using the right innominates (p=0.28).

Click on either graph for enlarged version.
 

Graph 1
Graph 2

In addition, a small subset of specimens (n=15) permitted direct comparison of the two innominate aging methods in the same person (Table 3 below).  These specimens were sufficiently intact to preserve both articular aspects.  By comparing the ages derived independently with each method, a test of aging accuracy was possible using Matched Pairs Studentsâ t-test (Graph 2 above).   No significant difference was found between the methods using the right innominates (df=8; p=0.28).
 

SUMMARY:  The two aging methods utilized in this analysis did not produce statistically significant differences in age profiles.  Both demonstrated a median age for the collection of 30-39 years with peaks in the later age groups. The pubic symphysis method showed a high percentage of individuals at 50+ years, while the auricular surface method peaked at 40-49 years.

This profile demonstrated longevity in the Byzantine St. Stephenâs community, although it should be noted that one of the difficulties of paleodemographic analysis is the tendency to truncate age groups for older members of a population. While the auricular surface allows greater sensitivity than the pubic symphysis for assessing the 50+ age range, exclusion of older adults is still problematic (9).   Some degree of truncation may have occurred for the St. Stephenâs collection given the disarticulated nature of the remains, and the inability to test for age across multiple bones from the same individual.  If indeed many monks of antiquity lived to venerable ages as some patristic literature suggests (10),  then such truncation may introduce slight error in the reconstruction of life at St. Stephenâs.  However, Van Gerven and Armelagos have argued that the Îover 55â age category usually constitutes between 1 and 10% of a collection, thus difficulties in assessing this age group introduce little statistical error in an overall age profile (11).

Given the potential for increased exposure to disease stress in an urban setting, the apparently plentiful but remedial medical abilities of the time (12)  and documented life spans for Homo sapiens(temporally and cross-culturally), the St. Stephenâs demographic profile quite likely represents the average adult life-span of the community.   These results tend to support the assertion by many scholars that accounts of extreme longevity in some patristic literature are anecdotal (13) -- either representing anomalies in life expectancy for the period or exaggerated claims to enhance the 'stature' of august individuals.
 

Future analysis of dental attrition, cranial suture closure, and bone histology aging methods will contribute supplementary biological evidence for age determination of this community (14).   In addition, continued synthesis of the texts describing life at this site and the region will facilitate further assessment of expected lifespan for Byzantine St. Stephenâs.

Click on the image of choice to learn more about each age determination method (under construction).

L-R:   Top row - pubic symphysis morphology, auricular surface morphology, age-related size distribution, tooth wear, epiphyseal closure, dental eruption patterns.


Footnotes:

1.  C. LOVEJOY, R. MEINDL, R. MENSFORTH, and T. BARTON, "Multifactorial Determination of Skeletal Age at Death: A Method and Blind Tests of Its Accuracy", American Journal of Physical Anthropology (hereafter AJPA) 68 (1985), 1-14. Return

2.  T. TODD, "Age Changes in the Pubic Bones, I:  The White Male Pubis", AJPA 3 (1920), 285-334.   Return

3.  R. MEINDL, C. LOVEJOY, and R. MENSFORTH. "Skeletal Age at Death:  Accuracy of Age Determination and Implications for Human Demography", Human Biology 55 (1985), 73-87.   It should be noted that a tendency to over-age individuals has been found after age 40 by some [S. BROOKS, "Skeletal Age at Death: The Reliability of Cranial and Pubic Age Indicators", AJPA 13 (1955), 567-597], while others claim under-aging of the 45+ year old individuals is problematic [L. AIELLO and T. MOLLESON, "Are Microscopic Ageing Techniques More Accurate than Macroscopic Ageing Techniques", JAS 20 (1993), 689-704]. Return

4.  Pubic symphysis data was collected by Prof. Dennis Van Gerven (University of Colorado). Return

5.  Thus, 0-9 years becomes decade 1, 11-9 years decade 2 and so on. Investigators arguing for expanded age categories include: A. GOODMAN, "On the Interpretation of Health from Skeletal Remains", Current Anthropology 34 no 3 (1993), 281-8; L. KONIGSBERG and S. FRANKENBERG, "Estimation of Age Structure in Anthropological Demography", AJPA 89 (1992), 235-56; P. SMITH, "An Approach to the Paleodemographic Analysis of Human Skeletal Remains from Archaeological Sites", Biblical Archaeology Today 1990, (Proceedings of the Second International Congress on Biblical Archaeology, Pre-Congress Symposium:  Population, Production, and Power, Jerusalem: IES, 1993), 2-13; and, D. VAN GERVEN, and G. ARMELAGOS, "Farewell to Paleodemography?  Rumors of its Death Have Been Greatly Exaggerated", JHE 12 (1983), 353-60.   Return

6.  C. LOVEJOY, R. MEINDL, T. PRZYBECK, and R. MENSFORTH, "Chronological Metamorphosis of the Auricular Surface of the Ilium: A New Method for the Determination of Adult Skeletal Age at Death", AJPA 68 (1985), 15-28.; S. SAUNDERS, C. FITZGERALD, T. ROGERS, C. DUDAR, and H. MCKILLOP, "A Test of Several Methods of Skeletal Age Estimation Using a Documented Archaeological Sample", Canadian Society of Forensic Science Journal 25 (1992), 97-117.   Return

7.  Also reminiscent of the Todd method is the tendency to underage 45+ year old individuals (SAUNDERS et al., "A Test", 97-100).  K. MURRAY and T. MURRAY ("A Test of the Auricular Surface Aging Method," Journal of Forensic Sciences (hereafter JFS) 36 no 4 (1991), 1162-9) warn that this method is useful in conjunction with other aging techniques, but should not stand alone as the sole criterion for age determination.   Return

8.  Auricular surface age data were collected by Alison French, Tel Ekron-Miqne Fellow at the Albright Institute for Archaeological Research in Jerusalem. Return

9.  T. WHITE, Human Osteology  (San Diego: Academic Press, 1991), 369-77.  For a discussion of the pitfalls of paleodemographic research, see:  J. BOCQUET-APPEL and  C. MASSETT, "Farewell to Paleodemography",  JHE  11 (1982), 321-33; J. WOOD, C. MILNER, H. HARPENDING, and R. WEISS, "The Osteological Paradox:  Problems of Inferring Prehistoric Health from Skeletal Samples", Current Anthropology 33 (1992), 343-58.  For counter-responses to these arguments, see:  A. GOODMAN, "On the Interpretation", 281-8, and D. VAN GERVEN and G. ARMELAGOS, "Farewell", 353-60.   Return

10. Examples from the patristic literature can be found in R. WILKEN, The Land Called Holy: Palestine in Christian History and Thought (New Haven: Yale University Press, 1992), 157;  D. CHITTY, The Desert a City, 96; Cyril (V. S. 183.17).   Return

11. D. VAN GERVEN and G. ARMELAGOS, "Farewell", 353-60.   Return

12. T. MILLER, "Byzantine Hospitals",  In John Scarborough, ed., Dumbarton Oaks Symposium on Byzantine Medicine, No 38 (Washington, DC: Meriden-Stinehour Press, 1984), 53-63; V NUTTON, "From Galen to Alexander:  Aspects of Medicine and Medical Practice in Late Antiquity", In John Scarborough, ed., Dumbarton Oaks Symposium on Byzantine Medicine, No 38 (Washington, DC: Meriden-Stinehour Press, 1984), 381-414; T. MILLER, The Birth of the Hospital in the Byzantine Empire (Baltimore: Johns Hopkins University Press, 1985), 132-6. Return

13. For a discussion of this topic, see:  J. BLENKINSOPP, "Life Expectancy in Ancient Palestine" Scandinavian Journal of the Old Testament 11 no 1 (1997), 44-55. Return

14. Several methods for determining age using degree of dental attrition are available and will be applied to this collection [D. BROTHWELL, Digging Up Bones  (Cornell: Cornell University Press, 1981), 51-7; B. SMITH, "Patterns of Molar Wear in Hunter-Gatherers and Agriculturalists", AJPA 63 (1984), 39-56].  R. MEINDL and C. LOVEJOY ["Ectocranial Suture Closure:  A Revised Method for the Determination of Skeletal Age at Death Based on the Lateral-Anterior Sutures", AJPA 68 (1985), 57-66] used the degree of fusion of the sutures of the skull for age estimation, and although the number of intact crania is small for this collection, the method will be employed on the limited sample size.  E. KERLEY ["The Microscopic Determination of Age in Human Bone", AJPA 23 (1965), 149-64] proposed a method, later modified [ER KERLEY and DH UBELAKER, "Revisions in the Microscopic Method of Estimation Age at Death in Human Cortical Bone", AJPA 49 (1978), 545-6] which utilized microscopic examination of the cellular structure of femoral midshaft samples in an assessment of age.   Return


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  Sex Reconstruction
  Stature Reconstruction
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