Abstract not available

This study analyzes the impact of biocultural change in vertebrae from Dickson Mounds. Dickson underwent a transition from hunting and gathering (PreMississippian) to greater reliance on maize (Middle Mississippian) between A.D. 950-1300. Previous research has found that with this transition health declined markedly. However, vertebrae have unique growth patterns which permit inference into health not possible using traditional paleopepidemiological techniques. Vertebral canals are mature by age five, while vertebral heights continue to grow past adolescence. Thus, depending on the duration of growth disruption, canals may be stunted without smaller heights. The brain and thymicolymphatic system also develop by age five, and small canals in the adult may be associated with morbidity and decreased life expectancy. Lumbar and thoracic vertebrae (n = 1,073), from 91 individuals (ages 15-55), as well as tibiae (n = 30), were analyzed for various aspects of their covariation within age, sex, and cultural groups. Results indicated that Mississippians, compared to PreMississippians, (combined sexes) had significantly decreased canal size, while their vertebral heights significantly increased. In PreMississippians, no difference in canal size was found between males and females. Males had larger heights. In Mississippians, females, compared to males, had significantly smaller canals and heights. Mississippian females, compared to PreMississippian females, had significantly smaller canals and heights. Mississippian males, compared to PreMississippian males, had smaller canals, but their heights increased. Small canal size was significantly associated with vertebral wedging. Wedging (anterior divided by posterior vertebral height) was used as a conservative measure of cancellous bone loss. Wedging cannot occur unless the cortical shell breaks down, and cancellous bone loss always precedes cortical loss. Harris lines, composed of cancellous bone, were significantly inversely correlated with wedging. This suggested that more cancellous bone in the tibiae was positively associated with more cancellous bone in the vertebral body. Lines were also consistently associated with larger tibial and vertebral morphometrics. Therefore, the use of adult Harris lines as indicators of morbidity must be reconsidered. Vertebral analysis offers important new insights into biocultural change at Dickson. Mississippian males apparently enjoyed better postnatal health compared to PreMississippian males. Females in the Mississippian declined in both prenatal and postnatal health. Clinical implications in modern populations are also discussed.

Social psychophysiology is concerned with the interrelationship between emotion, physiology, and the sociocultural environment. Evolutionary, developmental, physiological, medical, psychological, cross-cultural, and political economic aspects of human social psychophysiology are examined in this thesis. This combination, from a holistic anthropological approach, addresses the questions of why and how stress has grown to its current proportions in Western society. The psychophysiological system is not principally an adaptation for agonism ("fight or flight"); it is the biological foundation of an affective system, integral to the maintenance of human sociality. It is, therefore, not primarily suppressed aggressiveness which produces high levels of unrelieved stress in Western industrial society. Some aspects of industrial social organization contradict the basic conditions for human sociality and cause widespread social insecurity, anxiety, and physiological heterostasis. Different cultures define the characteristics of social value, upon which social acceptance, affiliation, and security are based, differently. Within stratified societies, status and security are linked. In Western industrial societies, class and ethnic status has an inverse relationship to the prevalance and magnitude of stressors, rates of anxiety, feelings of helplessness/hopelessness and inadequacy associated with depression, rates of most psychiatric illinesses, adrenal hormone levels, and rates of cardiovascular and other diseases related to stress. Non-western populations, recently integrated within an urban, capitalistic political economy at the least secure socioeconomic strata, also exhibit high levels of psychophysiological arousal. While other researchers have emphasized the stressfulness of acculturative change in itself, this dissertation focuses on the specifications of the economic and sociocultural context into which "modernizing" groups become integrated. A field study is reported, on stress in the lives of the Black British immigrants, who, like many Afro-Americans and working class whites, are systematically frustrated in their efforts to achieve material security and a satisfactory sense of social worth. The stress-effects of racism and class are discussed.

The delay in age at maturity associated with increased behavioral flexibility and prolonged life span in nonhuman primates is a potential demographic trap. In order to offset the lower reproductive rates and longer generation times, long-lived species must alter other aspects of their life histories. The purpose of this research is to demonstrate a method for measuring the demographic effects of such a change in life histories on population compositions and population growth rates among the nonhuman primates. A Leslie matrix projects stable population distributions and population growth rates. These projections are compared with census data or survivorship data from several species of nonhuman primates by analysis of angular divergence of vectors, comparison of sample populations to confidence intervals around a reference vector, and comparisons of cumulative survivorship that the stable population vectors represent. Most fluctuation in survivorship had little impact on the population growth rate and composition between trials. A significant effect was produced by extending reproduction for at least one age class, and the combination of extension of the reproductive span and increased infant survival produced large differences among projections. The extension of the reproductive span beyond that expected on the basis of a proportional extension of all life cycle stages is the way out of the demographic trap for members of the Order Primates.

The objective of this research is to better understand the number of potential mates as a variable for analyzing the processes which lead to genetic structure. To do this, variation in the number of potential mates over space and time is examined. In particular, the effects of demographic change, geographic location, and kinship within the mate pool are examined for their influence on the size of the mate pool, mating patterns, and genetic structure, in two historical populations. The method compares the effects of these variables in populations with different geographic structures, but similar histories of population growth and decline. The geographic difference is relevant since most potential mates analysis has been applied to island isolates. The similarity in demographic history is important since it allows some control over between-population comparisons. The study populations are North Ronaldsay, one of the Orkney Islands located off the east coast of Scotland, and Ashfield, Massachusetts, a town in the Connecticut River Valley. These populations fill the requirements of the study in that they share similar demographic histories, but are different in geographic characteristics. The expectations represent a null hypothesis that both populations should look the same. The results show that change in numbers of potential mates over time is not strictly related to change in population size, but responds to changes in the age range in which males enter the mate pool. These changes are not the result of distortions in the age-sex structure. There is considerable variation between individuals in their numbers of available mates in all time periods in both populations. North Ronaldsay shows very little intermarriage with neighboring populations, while in Ashfield geographically close populations contribute a significant number to the mate pool. Individuals who fail to marry on North Ronaldsay do not appear to have a larger proportion of kin as potential mates. In fact, there appear to be distinct mating preferences for some categories of kin. In Ashfield, very little kinship within the mate pool is observed. This is consistent with other studies of kinship in Connecticut Valley towns.

Transverse lines are a frequently used non-specific skeletal indicator of environmental insult in skeletal populations. The prevailing assumption is that transverse lines reflect acute episodes of nutritional, disease, or psychological insult followed by recovery. However, the patterning of transverse lines in skeletal samples generally does not correspond well with other indicators of nutrition and disease insult. Clinical studies suggest that the etiology of transverse line formation is not well understood. It has also been suggested that transverse line formation is conditioned by rate of growth, although this has not been systematically investigated for contemporary populations. This study was undertaken in order to examine the relationship between bone lengthening and the formation of transverse lines. Serial tibial radiographs from 104 individuals participating in the Denver Child Research Council growth study were used in this study. Analysis focused on semi-annual change in maximum tibial diaphyseal length and transverse line characteristics. The results of this study show that there is significant, positive relationship between greater semi-annual growth increment and the formation of transverse lines. This association is observed when all individuals are considered together and is shown within individuals as well. As demonstrated in other studies, line formation is age-related. Even accounting for variation due to age, there is still a statistically significant positive relationship between growth and line formation in both males and females, although this is slightly stronger among males. When the sample is treated cross-sectionally by age, the generally positive relationship between growth velocity and line formation holds, but it infrequently reaches statistical significance. An alternative explanation for transverse line formation derives from a body of experimental literature which examines the hormonal regulation and control of growth at the epiphyseal cartilage plate. It is argued that transverse lines are a by-product of local, tissue-level control of growth rate. These controls over cartilage cell proliferation would occur in circumstances of rapid bone lengthening as well as inadequate nutrition. Thus, while nutritional insult may be a sufficient but indirect cause of transverse line formation, it is not a necessary condition for lines to form.

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No description available.

In this dissertation, I test whether modern human adults are paedomorphic (juvenilized) with respect to Neandertals, whether bonobo adults are paedomorphic with respect to chimpanzees, and whether paedomorphosis, if it exists, results from neoteny sensu Gould (1977). Various approaches are used to compare the ontogenetic transformation characterizing each taxon. Descriptive statistics and one-tailed t-tests of consecutive life cycle stages that evaluate the null hypothesis of no growth, are used to determine at what point trait growth ceases within each taxon (Chapter 4). Growth curves, derived from piecewise regression, are used to determine rates and durations of absolute growth (Chapter 4). These modeled growth curves also figure prominently in testing for heterochronic product and process using the software program Hetpad (Chapter 6). Shape change is explored in three regions of the skull (calotte, face and mandible). These regions are analyzed separately to increase the representation of fragmentary Neandertal fossils. Relative growth patterns are assessed using growth allometries; Euclidean distances and principal components analysis of craniofacial shapes are employed to examine the similarity of infants, juveniles, subadults and adults within and across taxa (Chapter 5). The results suggest that modern humans are only slightly paedomorphic with respect to Neandertals, and that this paedomorphosis is manifested mainly in the masticatory apparatus. Surprisingly, Neandertals can be characterized as paedomorphic in aspects of calotte shape, and the relation of the lower to the upper face, with respect to modern humans. Bonobos, when compared to chimpanzees, can only be poorly characterized as general craniofacial paedomorphs. The paedomorphosis of bonobos, with respect to chimpanzees, is only slight, and is manifested mainly in the calotte region. Although the attribution of “weak” neoteny in bonobos vis-à-vis chimpanzees cannot be ruled out, the characterization of modern humans as neotenes with respect to Neandertals fails as an explanation to describe the craniofacial differences manifested in adults. Overall, the shape path differences exhibited by the four taxa, as well as the idiosyncracies of taxon-specific growth patterns, suggest that heterochrony explains only a portion of the craniofacial evolution of Homo and Pan. Many of the traits which characterize adults of the four taxa emerge early (before, during, or just after infancy). Only a few differences exhibited by adults arise later.

The assessment and interpretation of zinc (Zn) concentrations derived from chemical analyses of biological hard tissues has been troubled by the complexities inherent in working with an essential trace element implicated in several important biological processes. Because Zn is subject to some homeostatic control by the body and does not undergo a clear trophic level separation several researchers have suggested its utility for paleodietary reconstruction is severely limited. However, with an understanding of the nature of Zn physiology, nutrient interactions and local factors affecting bioavailability it may yet be possible to utilize measures of hard tissue Zn concentrations in evaluating diet, health and children's functional outcomes. Pre-and-postnatal enamel Zn levels were determined via laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) for 80 teeth collected from 46 infants participating in a large longitudinal study in the Solís Valley, Mexico, during the mid-1980s. Relationships between enamel Zn levels and ∼200 variables documenting maternal diet, infant growth, morbidity and cognitive development were explored. The results indicate that an infant's prenatal enamel Zn content reflects their mother's pregnancy dietary quality. Infants born into the poorest households, and who were exposed to poor quality diets, have the highest concentrations of zinc in their prenatal enamel. Further, prenatal enamel Zn levels are predictive of the cognitive development of Solís infants. Postnatal enamel zinc amounts reflect maternal weight gain during pregnancy and predict the onset of certain illnesses (e.g. common cold, influenza) during infancy. The uptake of Zn by postnatal enamel is likely determined by mothers' storage of zinc in bone over the years preceding her pregnancy, as well as by both her pregnancy and lactation diets. This research demonstrates that, despite the fact that zinc is an essential element, its variation within deciduous teeth can be understood in terms of variation in socioeconomic status and maternal diets, and that it can in turn be predictive of individuals' future functional outcomes. From a biocultural anthropological perspective these results are remarkable in that they clarify one of the mechanisms by which the biological effects of social inequality are recycled from one generation to the next.