James H. Mielke

Bone growth and development in prehistoric populations from Sudanese Nubia

The analysis of a large sample of skeletons from a number of Sudanese Nubian cemeteries demonstrates the usefulness of this material in the study of bone growth and development. A skeletal series from the Meroitic (B.C. 350-A.D. 350), X-Group (A.D. 350–550), and Christian (A.D. 550–1400) period were utilized in determining the rate of bone development and age related changes in the internal structure of the femur. Specifically, we have been able to demonstrate the following: 1. (i) The growth velocity determined from the long bones in the Nubian sample was similar but somewhat more irregular than the growth velocity of long bones in American boys studied longitudinally. 2. (2) Growth symmetry of long bones determined by the ratio of lengths shows a greater stability than that which occurs in American boys. 3. (3) Decrease in femoral cortical thickness with age was significant in Nubian females (P < 0·001), while the decrease in males was not significant. The loss of cortical bone tissue in Nubian females appears to begin earlier than similar changes in modern females. 4. (4) The density of femoral head trabecular bone organ volume decreases with age at similar rates in both males and females, but the females lose a larger percentage of density since they enter the age period (17 years) with a lower density. 5. (5) The average thickness of femoral head trabeculae decrease with age in males, while in females there is an increase in thickness. It appears that as cross-members decrease in thickness with age, struts increase in thickness. 6. (6) Microradiographic analysis of archeological material may provide an additional dimension to the study of bone turnover rates.

Historical epidemiology of smallpox in Åland, Finland: 1751–1890

We analyze a 140-year series of smallpox deaths in the Åland Islands, Finland. Vaccination, introduced in 1805, dramatically reduced the annual number of smallpox deaths. It also influenced the age distribution of smallpox deaths, changing smallpox from a childhood disease before 1805 to one which affected both adults and children after 1805. This appears to be due to the fact that Ålanders were usually vaccinated only once during childhood and often lost their immunity during adulthood. Spectral analysis of the prevaccination time series of smallpox deaths demonstrates a strong seven-year periodicity, reflecting the amount of time necessary to build up a cohort of nonimmune individuals. After the introduction of vaccination, the periodicity changes to eight years. The probability that a parish in Åland was affected by a smallpox epidemic is shown to be highly correlated with migration patterns and parish population sizes.

Smallpox and its eradication in Finland: implications for disease control.

analyses of demographic characteristics of mortality patterns. This is especially true for periods before the mid-nineteenth century, when mortality at the national level can usually be measured only by crude death rates, or in some cases, by estimates of life expectancy at birth.1 Even when it is possible to study changes in age-specific mortality for more than two centuries, as is the case in Finland and Sweden,2 cause-specific analyses are needed in order to understand fully the determinants of mortality changes in the past. Changes in death rates may be the result of several divergent trends in causespecific mortality when different diseases are responding to changes in social and economic conditions, population density, immunity levels, and medical intervention, among other things. The Finnish and Swedish population data are especially well-suited to such studies of cause-specific mortality because of the exceptionally long period covered, as well as their accuracy and detail. Among the various infectious diseases reported in these records, smallpox is particularly amenable to analysis. This is because (1) the disease had important demographic consequences for an extended period of time; (2) compared to many other diseases, it was relatively easy to diagnose even by non-physicians; (3) excellent data can be found regarding vaccination and other measures taken to control the disease. These considerations encouraged us to use the Finnish source materials in studies of longitudinal smallpox mortality data from the mid-eighteenth century onward. We have compared two ecologically and socially different areas in Finland, the Aland archipelago and the mainland parishes of Kitee and Raakkyla.3 In these studies it was shown that Jennerian vaccination was the prime factor affecting the changing patterns of smallpox mortalitv during much of the nineteenth centurv. In both of the above-mentioned areas.

Population structure of the Aland Islands, Finland.

The total description of population structure, as so well discussed by Harrison and Boyce,44 requires the integration of biological, social, and demographic data set in an ecological framework. This, by itself, is understood to be an unobtainable and unapproachable goal. Moreover, we recognize that a major aim of population research is to describe and understand the complex evolution of the population structure as well as to describe it at a single point in time. Unfortunately, process as such can never be inferred from structure and thus longitudinal perspectives are obligate. The time span underlying a processual problem varies according to the focus of the research, itself partially limited by human factors and the kinds of data which can be obtained (historical, archeological, demographic, biological, etc.). The study of population structure therefore involves both studies with a short time span, such as analyses of pathological or normal biological development or recent sociohistoric changes, and a long-term perspective on the macroevolutionary history antecedent to the contemporary biological and social structure.

Historical Population Structure of the Åland Islands, Finland

Historical demography is one of a number of types of historical investigations that together comprise quantitative history. As a method, it is primarily concerned with ascertaining facts with regard to the demographic characteristics of populations in the past (e.g., fertility and mortality schedules, marriage and migration patterns, household and family structures). As a discipline, historical demography may be thought of as the process of reasoning about the mutual interaction of population and history (Hollingsworth, 1969). That is, how do the events of history, both long and short term, affect population; and, conversely, in what ways might the demographic characteristics of a population influence historical and social trends? At the same time, anthropology is concerned with population genetic structure and the historical, social, and demographic features that together influence this genetic composition.

Marital exogamy in the Aland Islands Finland 1750-1949.

Marriage records from 1750 through 1949 were used to examine effects of population size, geographic distance, and temporal change on rates of marital exogamy in the Aland Islands, Finland. Exogamy rates for individuals (not couples) were computed for 15 Aland parishes in each of four 50-year time periods, giving a total of 60 observations. These rates were analysed with respect to population size using a quadratic regression model. Regression analyses were also used to examine the relationship of marital exogamy with two measures of geographic distance--average distance to all other parishes and nearest-neighbour distance. Analysis of variance was used to examine temporal trends. Multiple regression analyses were used to examine all of these factors simultaneously. Marital exogamy is highest in smaller and larger populations, and less in medium-sized populations. Higher exogamy rates in small populations are related to the lack of available mates in small groups. Higher exogamy rates in larger populations may reflect economic attraction of larger groups. Exogamy rates are lower in the more geographically isolated parishes. From 1750 through 1899 there is little change in exogamy rates, whereas exogamy rates double after 1900. This temporal change reflects changes in transportation technology and other cultural factors promoting increased migration. The multiple regression model shows population size, geographic distance, and temporal change are all significant correlates of exogamy, collectively explaining a large percentage of variation in rates (R2 = 0.79).

Predicting smallpox epidemics: A statistical analysis of two Finnish populations

We analysis data on death due to smallpox in two subdivided Finish populations, the relatively isolated Åland Islands and the mainland parish of Kitee. The data span a 135‐year time period (1750–1885). Logisitic regression and Cox proportional hazards models are used to assess the effects of predictive variables on (1) the probability that an individual subdivision experiences an epidemic and (2) the length of the time period between two epidemics in each subdivision. The predictive variables include population sizes, migration rates, geographic distance, and presence or absence of vaccination. Vaccination was found to be the single most important predicative variable (odds ratio = 6.3 in Åland and 4.4 in Kitee). No other variable were significant predicators in Kitee, while geographic distance was an additional significant predicator in Åland (odds ratio = 1.05). As expected, vaccination and geographic distance were both negatively associated with the probability of epidemic occurrence.

Dental Variation in Black Carib Populations

Many recent studies have demonstrated that tooth size and morphology may be used to assess population affinities among groups that have experienced varying degrees of microdifferentiation (Bailit et al., 1968; Bailit, 1975; Baume and Crawford, 1978; Boyd, 1972; Crawford et al., 1975; Friedlaender, 1975; O’Rourke, 1916a,b; O’Rourke and Crawford, 1976, 1980; Sofaer et al., 1972). While the dental traits themselves may be evolutionarily somewhat more conservative than simpler genetic polymorphisms, their relative ease of collection, permanence, and traditional importance in macroevolutionary studies make them an important and appropriate data base from which to evaluate trends in microevolution.

Anthropological studies of disease

Larsen, Clark Spencer and George R. Milner, eds. In the Wake of Contact: Biological Responses to Conquest. New York: Wiley‐Liss, 1994. viii + 206 pp. including index.

The Analysis of prehistoric diets

89.00 cloth. Mascie‐Taylor, C. G. N., ed. The Anthropology of Disease. Oxford: Oxford University Press, 1993. ix + 169 pp. including index.