Barta, Dr. Jodi Lynn, U. of Toronto, Mississauga, Canada - To aid research on 'The Relationship Between Skin Pigmentation and Vitamin D Insufficiency in Northern Latitudes'
DR. JODI LYNN BARTA, University of Toronto, Mississauga, Canada, received funding in October 2007 to aid research on 'The Relationship between Skin Pigmentation and Vitamin D Insufficiency in Northern Latitudes.' This project examined the effects that changes in season have on vitamin D concentrations in individuals with varying levels of melanin in their skin in order to clarify the relationship between constitutive pigmentation and vitamin D status in otherwise healthy young adults of diverse ancestry living in northern latitudes. Preliminary data collected show that those with higher levels of melanin in their skin are at consistently higher risk of vitamin D insufficiency and deficiency, thus supporting the UVR hypothesis and highlighting the evolutionary significance of skin pigmentation as it relates to geographic origins and the importance of maintaining adequate vitamin D levels. Given the profound effects that vitamin D insufficiency and deficiency have on the human body, it was surprising that mean vitamin D concentrations in all ancestry groups were below adequate (75 nmol/L) regardless of season, despite the fact that mean vitamin D intakes in both late summer (296.72 IU) and winter (281.54 IU) were above current recommended adequate intake for adults (200 IU/day). Further research is necessary to precisely determine the vitamin D requirements of individuals of diverse ancestry living in northern latitudes and address the need for higher vitamin D intakes through supplementation and/or improved food fortification strategies to meet requirements and improve overall public health.
Froehle, Andrew William, U. of California, San Diego, La Jolla, CA - To aid research on 'Physical Activity and Basal Metabolic Rate in Postmenopausal Women,' supervised by Dr. Margaret J. Schoeninger
ANDREW WILLIAM FROEHLE, then a student at University of California - San Diego, La Jolla, California, received a grant in October 2007 to aid research on 'Physical Activity and Basal Metabolic Rate in postmenopausal Women,' supervised by Dr. Margaret J. Schoeninger. The project investigated the relationship between age, exercise and basal metabolic rate (BMR) in postmenopausal women, comparing two subgroups: 'active' (>5 hours exercise/week) and 'training' (sedentary at baseline, completed four-month exercise program). Across the entire sample, BMR correlated significantly with fat free mass (FFM; P<0.001, R=0.862) and physical activity level (PAL; P=0.004, R=0.542), but not with age or maximal aerobic capacity (VO2MAX). At baseline, subgroups differed significantly for BMR (P=0.005) and VO2MAX (P=0.006); active women were also 4.9 kg heavier (FFM) than sedentary women (not significant: P=0.077). Within the active group, no variables changed significantly over the study period. Meanwhile, the training sample exhibited significant increases over baseline in VO2MAX (P=0.015) and BMR (P=0.002), despite no change in FFM (P=0.952). Controlling for effects of the covariate FFM, subgroups differed significantly for BMR at baseline (P=0.007), but not at the end of the study (P=0.089). Results suggest that in this population, both short- and long-term exercise associate similarly with elevations in BMR above sedentary levels. Contrary to some research, this may not be tied to increased FFM. These results have implications for preventative exercise prescription against age-related health risks, and will help refine models of metabolic physiology in active postmenopausal women.
Froehle, Andrew W., S.R. Hopkins, L Natarajan, and M.J. Schoeninger. 2013. Moderate to High Levels of Exercise are Associated with Higher Resting Energy Expenditure in Community-dwelling Postmenopausal Women. Applied Physiology, Nutrition, and Metabolism 38(11):1147-1153.
Klein, Laura Danielle, Harvard U., Cambridge, MA - To aid research on 'Impacts of Maternal Disease Ecology on Milk Immunofactors and Infant Immune System Development,' supervised by Dr. Katherine J. Hinde
Preliminary abstract: Mothers' milk provides crucial immunological protection to the infant during early life. However, little is known about how the immune molecules that are present in milk vary among women living in vastly different nutritional, disease, and cultural ecologies. This project will use a longitudinal study in a population of small-scale agriculturalists at the Mogielica Human Ecology Study Site in southern Poland to investigate how aspects of the local environment, including diet and disease exposure, relate to the variation in composition of immune factors in breast milk within a population. This project will also examine how variation in mothers' milk might influence infant immune system development by taking advantage of a regularly schedule vaccine that mimics a natural immune challenge.
Paschetta, Carolina Andrea, U. Nacional de Rio Cuarto, Puerto Madryn, Argentina - To aid research on 'Dietary Shifts During Modem Human Evolution and their Effect on Craniofacial Size and Shape,' supervised by Dr. Rolando Gonzalez-Jose
Preliminary abstract: The craniofacial phenotype can suffer changes promoted by epigenetic or environmental factors. Among them, masticatory mechanical stress is perhaps one of the most important epigenetic stimuli which acted during the recent evolution of our species. In particular, technological transition from hunting-gathering is invoked to be concomitant with a significant reduction of masticatory stress. The main objective is quantify the differences in modern human samples with different economic strategies (hunter/gatherers, farmers, etc.), not only in the overall skull morphology, as well as in localized structures, in order to detect common, recurrent changes in craniofacial size and shape due to environmental stimuli. A geometric morphometrics techniques will be used to track these changes on at least three cases of economic transitions on New World populations. Changes observed in concomitance on all the transitions will be, in consequence, postulated as good candidates of plastic structures which probably promoted rapid evolution of modern humans across different adaptive (dietary, nutritional) shifts.
Vitzthum, Dr. Virginia Judith, State U. of New York, Binghamton, NY - To aid research on 'Testing Hypotheses of the Dietary Determinants of Ovarian Hormones: A Comparative Study of Three Populations'
DR. VIRGINIA J. VITZTHUM, Institute of Primary and Preventative Health Care, Binghamton University, Binghamton, New York, was awarded a grant in May 2006 to aid research on 'Testing Hypotheses of the Dietary Determinants of Ovarian Hormones: A Comparative Study of Three Populations.' This research is part of a larger project to elucidate the ecological, behavioral, and ontogenetic determinants of variation in women's reproductive functioning. This phase of the project evaluated the relative importance of total caloric intake versus dietary fat consumption in determining ovarian steroid variation by comparing hormone levels in nomadic-herding Mongolian women (high fat/low calorie diets) with those in previously collected samples of agropastoral Bolivian women (low fat/low calorie diets) and Chicago women (high fat/high calorie diets). Daily biological samples spanning a menstrual cycle and data on covariates were collected from 40 nomadic Mongolian women during July through September 2006. Assays were conducted in collaboration with Dr. Tobias Deschner at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. Initial analyses suggest that ovarian steroid levels are at least as high as those of U.S. women, suggesting that dietary fat may be the more important factor. In addition to increasing current understanding of the sources of variation in ovarian functioning, this finding suggests that the modulation of reproductive functioning during a woman's lifespan may be sensitive to variation in dietary fat intake. Ongoing research includes the collection of a comparative sample of German women and planned research includes genetic analyses to ascertain the potential contribution of genotypic variation to hormonal variation.
Bekelman, Traci Allison, U. of Colorado, Boulder, CO - To aid research on 'Using the Protein Leverage Hypothesis to Understand Socioeconomic Variation in Diet and Body Size,' supervised by Dr. Darna Dufour
Preliminary abstract: The primary objective of the proposed research is to provide insights into the factors responsible for the larger body size of urban Latin American women of low- versus high-socioeconomic status (SES). To accomplish this we intend to focus on dietary factors, of which surprisingly little is known, and specifically to test hypotheses derived from the Protein Leverage Hypothesis, a theoretical model developed by Simpson and Raubenheimer. Guided by the Protein Leverage Hypothesis, this study will test an explanation for the inverse relationship between SES and body size: limited access to dietary protein in low-SES women leads to a lower proportion of protein in the diet which, in turn, drives higher energy intake. To accomplish the research objective, anthropometry and weighed food records will be collected from 134 urban women in low- and high-SES neighborhoods in San José, Costa Rica. We will also examine perceived economic barriers to protein access using structured interviews and the strategies women use to overcome those barriers using a Geographic Information System (GIS). This research will generate new knowledge about how biology, culture and the physical and social environments interact to influence energy intake and body size.
Fujita, Masako, U. of Washington, Seattle, WA - To aid 'An Evolutionary Perspective on Mother-Offspring Vitamin A Transfer,' supervised by Dr. Bettina Shell Duncan
MASAKO FUJITA, then a student at University of Washington, Seattle, Washington, was awarded a grant in April 2006 to aid research on 'An Evolutionary Perspective on Mother-Offspring Vitamin A Transfer,' supervised by Dr. Bettina Shell-Duncan. This project investigated the perplexing decline in breastmilk vitamin A (VA) concentrations across the postpartum months. Applying the concept of life-history tradeoffs, this decline was hypothesized to be an evolved maternal reproductive strategy optimizing physiological reallocation of VA between competing needs of current and future reproduction depending on postpartum time and reproductive status. The hypotheses were tested using breastmilk VA and maternal hepatic VA data, collected among 250 lactating Ariaal mothers in northern Kenya, as indices for maternal investment respectively on current reproduction and future reproduction. Data indicated maternal hepatic VA is in a trade-off relationship with milk VA postpartum. Breastmilk VA does not track hepatic VA but instead declines despite increasing hepatic stores in the late postpartum period. Results shed light on the evolutionary ecological heritage of human micronutrient metabolism and human reproduction, and further illuminate policy directions for currently recommended public health strategy of high-dose postpartum maternal VA supplementation.
Fujita, Masako, Eric Roth, Yun-Kia Lo, Carolyn Hurst, Jennifer Vollner, and Ashley Kendell. 2012. In Poor Families, Mothers' Milk is Richer for Daughters than Sons: A Test of Trivers-Willard Hypothesis in Agropastoral Settlements in Northern Kenya. American Journal of Physical Anthropology 149(1):52-59.
Kreager, Dr. Philip, Oxford U., Oxford, UK - To aid workshop on 'Population in the Human Sciences: Concepts, Models, Evidence,' 2011, Oxford, in collaboration with Dr. Stanley Ulijaszek
Preliminary abstract: The workshop addresses the need for review and assessment of the framework of interdisciplinary population studies. Limits to prevailing postwar paradigms like the Evolutionary Synthesis and Demographic Transition were becoming evident by the 1970s. Subsequent decades have witnessed an immense expansion of population modelling and related empirical inquiry, with new genetic developments that have reshaped evolutionary, population, and developmental biology. The rise of anthropological and historical demography, and social network analysis, have played major roles in rethinking modern and earlier population history. More recently, the emergence of sub-disciplines like biodemography and evolutionary anthropology, and growing links between evolutionary and developmental biology, indicate a growing convergence biological and social approaches to population. New modelling techniques, particularly relating to network analysis, are applied across these several fields, and at several levels of analysis. The several developments have not, however, displaced the older paradigms and the concepts and methods of population analysis on which they rested. Current developments often coexist uneasily with them. The workshop is designed to bring together researchers at the forefront of these developments, drawing on their and related work to consider current concepts and practices used to construct and analyse populations. Discussion will emphasize comparison of similarities and differences amongst models, methods and concepts; potential cross-fertilisation of research; and whether a new cohesive framework for population studies is emerging. The workshop marks the 40th anniversary of the founding of the Human Sciences Programme at Oxford, and of the symposium on population supported by Wenner-Gren that was held at that time. Proceedings of this workshop, like its predecessor, will be published.
Patil, Dr. Crystal L., U. of Illinois, Chicago, IL - To aid research on 'A Biocultural Examination of the Peripartum Period'
DR. CRYSTAL L. PATIL, University of Illinois, Chicago, Illinois, was awarded funding in April 2008, to aid research on 'A Biocultural Examination of the Peripartum Period.' Fieldwork was carried out from May-August in 2009 and 2010, among subsistence agriculturalists living in north-central Tanzania. Using a mixed-methods ethnographically-informed protocol the project examined: 1) the patterning of the peripartum; and 2) nodes of decision-making around place of birth. The study compared narratives collected from women, traditional and biomedical health practitioners, health administrators and support staff, and community leaders, and observed births in the hospital. Sociopolitical, economic, and environmental conditions were discussed and themes emerging from these interviews were integrated into a community-level survey. Three villages, at various distances from the hospital were included in the survey. Targeted follow-up interviews were conducted to better understand nodes in the pathway of decision-making in birth. In addition to publications, these results will be integrated into policy briefs and presented to the community for use in local policy-making in hopes of reducing maternal mortality.
Wander, Katherine Susan, U. of Washington, Seattle, WA - To aid research on 'Immunocompetence and the Hygiene Hypothesis,' supervised by Dr. Bettina Shell-Duncan
KATHERINE S. WANDER, then a student at University of Washington, Seattle, Washington, received funding in October 2009 to aid research on 'Immunocompetence and the Hygiene Hypothesis,' supervised by Dr. Bettina Shell-Duncan. Extensive research in allergy epidemiology has demonstrated that early exposure to infectious agents is associated with lower risk of allergic disease. An evolutionary perspective suggests that such early exposure may affect not only pathological immune responses to allergens, but also healthy immune responses to pathogens as a developmental adaptation, tailoring immune responses to the local infectious disease ecology. To evaluate this hypothesis, this project evaluated associations between early life infectious disease exposure and: 1) allergic disease; and 2) delayed-type hypersensitivity to Candin (an immune response to pathogen antigen, indicating immunocompetence). Consistent with finding in the US and Europe, large family size was associated with lower risk of diagnosed allergic disease. Consistent with the hypothesized developmental adaptation in immune system development, large family size, hospitalization during infancy with an infectious disease, and BCG vaccination scar were positively associated with immunocompetence (delayed-type hypersensitivity to Candin). These results suggest that not only do early infections discourage the pathological immune responses that result in allergy, they also promote healthy immune responses to pathogens, reflecting adaptive plasticity in immune system development.