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Total daily energy expenditure (“total expenditure”, MJ/d) reflects daily energy needs and is a critical variable in human health and physiology, yet it is unclear how daily expenditure changes over the life course. Here, we analyze a large, globally diverse database of total expenditure measured by the doubly labeled water method for males and females aged 8 days to 95 yr. We show that total expenditure is strongly related to fat free mass in a power-law manner and identify four distinct metabolic life stages. Fat free mass-adjusted daily expenditure accelerates rapidly in neonates (0-1yr) to ~46% above adult values at ~1 yr, declines slowly throughout childhood and adolescence (1-20 yr) to adult levels at ~20 yr, remains stable in adulthood (20-60 yr) even during pregnancy, and declines in older adults (60+ yr). These changes in total expenditure shed new light on human development and aging and should help shape nutrition and health strategies across the lifespan.

In mammals, trait variation is often reported to be greater among males than females. However, to date, mainly only morphological traits have been studied. Energy expenditure represents the metabolic costs of multiple physical, physiological, and behavioral traits. Energy expenditure could exhibit particularly high greater male variation through a cumulative effect if those traits mostly exhibit greater male variation, or a lack of greater male variation if many of them do not. Sex differences in energy expenditure variation have been little explored. We analyzed a large database on energy expenditure in adult humans (1494 males and 3108 females) to investigate whether humans have evolved sex differences in the degree of interindividual variation in energy expenditure. We found that, even when statistically comparing males and females of the same age, height, and body composition, there is much more variation in total, activity, and basal energy expenditure among males. However, with aging, variation in total energy expenditure decreases, and because this happens more rapidly in males, the magnitude of greater male variation, though still large, is attenuated in older age groups. Considerably greater male variation in both total and activity energy expenditure could be explained by greater male variation in levels of daily activity. The considerably greater male variation in basal energy expenditure is remarkable and may be explained, at least in part, by greater male variation in the size of energy-demanding organs. If energy expenditure is a trait that is of indirect interest to females when choosing a sexual partner, this would suggest that energy expenditure is under sexual selection. However, we present a novel energetics model demonstrating that it is also possible that females have been under stabilizing selection pressure for an intermediate basal energy expenditure to maximize energy available for reproduction. (C) 2022 The Author(s). Published by Elsevier Ltd.

Publisher Copyright: © 2021 The Authors Understanding the impacts of activity on energy balance is crucial. Increasing levels of activity may bring diminishing returns in energy expenditure because of compensatory responses in non-activity energy expenditures.1–3 This suggestion has profound implications for both the evolution of metabolism and human health. It implies that a long-term increase in activity does not directly translate into an increase in total energy expenditure (TEE) because other components of TEE may decrease in response—energy compensation. We used the largest dataset compiled on adult TEE and basal energy expenditure (BEE) (n = 1,754) of people living normal lives to find that energy compensation by a typical human averages 28% due to reduced BEE; this suggests that only 72% of the extra calories we burn from additional activity translates into extra calories burned that day. Moreover, the degree of energy compensation varied considerably between people of different body compositions. This association between compensation and adiposity could be due to among-individual differences in compensation: people who compensate more may be more likely to accumulate body fat. Alternatively, the process might occur within individuals: as we get fatter, our body might compensate more strongly for the calories burned during activity, making losing fat progressively more difficult. Determining the causality of the relationship between energy compensation and adiposity will be key to improving public health strategies regarding obesity.

Summary The doubly labeled water (DLW) method measures total energy expenditure (TEE) in free-living subjects. Several equations are used to convert isotopic data into TEE. Using the International Atomic Energy Agency (IAEA) DLW database (5,756 measurements of adults and children), we show considerable variability is introduced by different equations. The estimated rCO2 is sensitive to the dilution space ratio (DSR) of the two isotopes. Based on performance in validation studies, we propose a new equation based on a new estimate of the mean DSR. The DSR is lower at low body masses (, Graphical Abstract, Highlights 5,756 doubly labeled water (DLW) measures highlight variation from calculation equation We derive here new equations for calculating CO2 production when using DLW These equations outperform previous equations in validation studies We recommend these equations should be adopted in future studies using DLW in humans, Speakman et al. use a large database of doubly labeled water measurements to show the choice of equation for the calculation of energy expenditure introduces significant variation into the final estimate. They then derive new equations that outperform previous equations in validation studies against chamber calorimetry.

Some research suggests women are more likely to allocate additional resources to their children than are men. This perception has influenced policies such as in-kind food transfer programs and cash transfer programs, which often target women recipients. We assess whether targeting in-kind rice transfers to female versus male adult household members has a differential impact on children's short-run nutritional status. We estimate the impacts of transfers of edible rice and rice seeds, randomly allocated to female or male adults, on three anthropometric indicators: BMI-for-age, arm-muscle area, and triceps skinfold thickness. The trial includes 481 children aged 3-11 years in a horticultural-foraging society of native Amazonians in Bolivia. On average, the gender of the transfer recipient does not influence child anthropometric dimensions, possibly due to norms of cooperation and sharing within and between households. We find limited evidence of heterogeneity in impacts. Transfers to women help children who were growth stunted at baseline to partially catch-up to their better-nourished age-sex peers and help boys (but not girls) and children in higher-income households increase their BMI-for-age. The results of this research point to the importance of considering cultural context in determining if allocating food transfers according to gender are most effective.

Background Evolutionary theory suggests that natural selection favors the evolution of cognitive abilities which allow humans to use facial cues to assess traits of others. The use of facial and somatic cues by humans has been studied mainly in western industrialized countries, leaving unanswered whether results are valid across cultures. Methodology/Principal Findings Our objectives were to test (i) if previous finding about raters' ability to get accurate information about an individual by looking at his facial photograph held in low-income non western rural societies and (ii) whether women and men differ in this ability. To answer the questions we did a study during July-August 2007 among the Tsimane', a native Amazonian society of foragers-farmers in Bolivia. We asked 40 females and 40 males 16–25 years of age to rate four traits in 93 facial photographs of other Tsimane' males. The four traits were based on sexual selection theory, and included health, dominance, knowledge, and sociability. The rating scale for each trait ranged from one (least) to four (most). The average rating for each trait was calculated for each individual in the photograph and regressed against objective measures of the trait from the person in the photograph. We found that (i) female Tsimane' raters were able to assess facial cues related to health, dominance, and knowledge and (ii) male Tsimane' raters were able to assess facial cues related to dominance, knowledge, and sociability. Conclusions/Significance Our results support the existence of a human ability to identify objective traits from facial cues, as suggested by evolutionary theory.

Background New quantitative methods to collect and analyze data have produced novel findings in ethnobiology. A common application of quantitative methods in ethnobiology is to assess the traditional ecological knowledge of individuals. Few studies have addressed reliability of indices of traditional ecological knowledge constructed with different quantitative methods. Methods We assessed the associations among eight indices of traditional ecological knowledge from data collected from 650 native Amazonians. We computed Spearman correlations, Chronbach's alpha, and principal components factor analysis for the eight indices. Results We found that indices derived from different raw data were weakly correlated (rho0.5; p < 0.001). We also found a relatively high internal consistency across data from the eight indices (Chronbach's alpha = 0.78). Last, results from a principal components factor analysis of the eight indices suggest that the eight indices were positively related, although the association was low when considering only the first factor. Conclusion A possible explanation for the relatively low correlation between indices derived from different raw data, but relatively high internal consistency of the eight indices is that the methods capture different aspects of an individual's traditional ecological knowledge. To develop a reliable measure of traditional ecological knowledge, researchers should collect raw data using a variety of methods and then generate an aggregated measure that contains data from the various components of traditional ecological knowledge. Failure to do this will hinder cross-cultural comparisons.

Background Humans and other primates have evolved particular morphological and biological traits (e.g., larger brains, slower growth, longer-lived offspring) that distinguish them from most other mammals. The evolution of many distinctive human characteristics, such as our large brain sizes, reduced gut sizes, and high activity budgets, suggest major energetic and dietary shifts. Main body Over the course of the last three million years, hominin brain sizes tripled. It is often taken for granted that the benefit of a larger brain is an increase in “intelligence” that makes us stand out among other mammals, including our nearest relatives, the primates. In the case of humans, brain expansion was associated with changes in diet, foraging, and energy metabolism. The first marked expansion occurred with the appearance of the genus Homo. Improved diet quality, allomaternal subsidies, cognitive buffering [by earlier weaning and longer juvenile periods], reduced costs for locomotion and by cooperative behavior, and reduced allocation to production, all operated simultaneously, thus enabling the extraordinary brain enlargement in our lineage. Conclusion It appears that major expansion of brain size in the human lineage is the product of synergistically interacting dietary/nutritional and social forces. Although dietary change was not being the sole force responsible for the evolution of large brain size, the exploitation of high-quality foods likely fueled the energetic costs of larger brains and necessitated more complex behaviors that would have selected for greater brain size.

Background: Seasons affect many social, economic, and biological outcomes, particularly in low-resource settings, and some studies suggest that birth season affects child growth. Aim: To study a predictor of stunting that has received limited attention: birth season. Subjects and methods: This study uses cross-sectional data collected during 2008 in a low-resource society of horticulturists-foragers in the Bolivian Amazon, Tsimane’. It estimates the associations between birth months and height-for-age Z-scores (HAZ) for 562 girls and 546 boys separately, from birth until age 11 years or pre-puberty, which in this society occurs ∼13–14 years. Results: Children born during the rainy season (February–May) were shorter, while children born during the end of the dry season and the start of the rainy season (August–November) were taller, both compared with their age–sex peers born during the rest of the year. The correlations of birth season with HAZ were stronger for boys than for girls. Controlling for birth season, there is some evidence of eventual partial catch-up growth, with the HAZ of girls or boys worsening until ∼ age 4–5 years, but improving thereafter. By age 6 years, many girls and boys had ceased to be stunted, irrespective of birth season. Conclusion: The results suggest that redressing stunting will require attention to conditions in utero, infancy and late childhood.

OBJECTIVE This study examined changes in body fat and diet among Tsimane' forager-horticulturalists and assessed how dietary shifts relate to increases in adiposity between 2002 and 2010. METHODS Longitudinal anthropometric and household-level dietary recall data from 365 men and 339 women aged ≥20 years in the Tsimane' Amazonian Panel Study were used. Multilevel mixed-effects models estimated how BMI, body fat percentage, waist circumference, skinfolds, and fat-free mass relate to household consumption of crops, hunted or fished foods, domesticated animal products, cooking oil, and refined grains and sugar. RESULTS Women's prevalence of overweight and obesity increased from 22.6% and 2.4% in 2002 to 28.8% and 8.9% in 2010, respectively, and BMI increased by 0.60% ± 0.12% per year (P

Background: Childhood growth stunting is negatively associated with cognitive and health outcomes, and is claimed to be irreversible after age 2. Aim: To estimate growth rates for children aged 2–7 who were stunted (sex-age standardised z-score [HAZ] −1) at baseline and tracked annually until age 11; frequency of movement among height categories; and variation in height predicted by early childhood height. Subjects and methods: This study used a 9-year annual panel (2002–2010) from a native Amazonian society of horticulturalists–foragers (Tsimane’; n = 174 girls; 179 boys at baseline). Descriptive statistics and random-effect regressions were used. Results: This study found some evidence of catch-up growth in HAZ, but persistent height deficits. Children stunted at baseline improved 1 HAZ unit by age 11 and had higher annual growth rates than non-stunted children. Marginally-stunted boys had a 0.1 HAZ units higher annual growth rate than non-stunted boys. Despite some catch up, ∼ 80% of marginally-stunted children at baseline remained marginally-stunted by age 11. The height deficit increased from age 2 to 11. Modest year-to-year movement was found between height categories. Conclusions: The prevalence of growth faltering among the Tsimane’ has declined, but hurdles still substantially lock children into height categories.

Objectives: To examine links between same-sex relationship formalisation – such as registered domestic partnerships and commitment ceremony unions – and mental health among lesbians and gay men, after controlling for differences in other relationship characteristics. Methods: Data were collected via an online survey of a national sample of Australian lesbians and gay men aged 16 years and older, with the sample for analysis confined to those in a same-sex relationship (n=1,420). The K10 Psychological Distress Scale was used as an indicator of mental health. Results: Being in a formalised relationship was associated with lower distress for those aged 16–39 years but not for those aged 40+ years; whereas, intending to formalise was associated with higher distress among the older group. These associations remained significant after controlling for cohabitation, feeling able to seek partner emotional support, relationship tenure and financial arrangements. Conclusions and implications: Relationship formalisation appears to be an important protective factor for mental health among gay men and lesbians, especially among younger sexual minority individuals. These findings suggest that affording same-sex couples the opportunity to formalise their relationship is not only a civil rights issue but also a public health issue.

This brief communication contains a description of the 2002-2010 annual panel collected by the Tsimane' Amazonian Panel Study team. The study took place among the Tsimane', a native Amazonian society of forager-horticulturalists. The team tracked a wide range of socio-economic and anthropometric variables from all residents (633 adults ≥16 years; 820 children) in 13 villages along the Maniqui River, Department of Beni. The panel is ideally suited to examine how market exposure and modernization affect the well-being of a highly autarkic population and to examine human growth in a non-Western rural setting.

OBJECTIVES This study provides the first investigation of non-shivering thermogenesis (NST) and brown adipose tissue (BAT) activity among an indigenous circumpolar population, the Yakut of northeastern Siberia. The study also examines the health significance of BAT activity in this population by testing the relationships between BAT thermogenesis and biomarkers of cardio-metabolic disease risk, such as percent body fat and blood glucose and cholesterol levels. METHODS Data were collected in the Sakha Republic (Yakutia) for 31 men and 43 women. Change in energy expenditure and BAT thermogenesis were quantified after a 30-minute mild cooling condition. Anthropometric dimensions, blood glucose, and lipid levels were also collected. RESULTS On average, the skin temperature of the supraclavicular area was constant after cooling while the skin temperature of a point on the sternum dropped significantly (P

The high energetic costs of human brain development have been hypothesized to explain distinctive human traits, including exceptionally slow and protracted preadult growth. Although widely assumed to constrain life-history evolution, the metabolic requirements of the growing human brain are unknown. We combined previously collected PET and MRI data to calculate the human brain's glucose use from birth to adulthood, which we compare with body growth rate. We evaluate the strength of brain-body metabolic trade-offs using the ratios of brain glucose uptake to the body's resting metabolic rate (RMR) and daily energy requirements (DER) expressed in glucose-gram equivalents (glucosermr% and glucoseder%). We find that glucosermr% and glucoseder% do not peak at birth (52.5% and 59.8% of RMR, or 35.4% and 38.7% of DER, for males and females, respectively), when relative brain size is largest, but rather in childhood (66.3% and 65.0% of RMR and 43.3% and 43.8% of DER). Body-weight growth (dw/dt) and both glucosermr% and glucoseder% are strongly, inversely related: soon after birth, increases in brain glucose demand are accompanied by proportionate decreases in dw/dt. Ages of peak brain glucose demand and lowest dw/dt co-occur and subsequent developmental declines in brain metabolism are matched by proportionate increases in dw/dt until puberty. The finding that human brain glucose demands peak during childhood, and evidence that brain metabolism and body growth rate covary inversely across development, support the hypothesis that the high costs of human brain development require compensatory slowing of body growth rate.

Although the health benefits of exercise and exposure to nature are well established, most evidence of their interaction comes from acute observations of single sessions of activity. However, documenting improved health outcomes requires ongoing interventions, measurement of multiple outcomes, and longitudinal analyses. We conducted a pilot study to guide the development of a protocol for future longitudinal studies that would assess multiple physiological and psychological outcomes. Herein, we report psychological outcomes measured from thirty-eight participants before and after three conditions: a 50 min walk on a forest path, a 50 min walk along a busy road, and a period of activities of daily living. Changes in positive and negative affect, anxiety, perceived stress, and working memory are reported. We benchmark these results to existing studies that used similar protocols and also identify elements of the protocol that might impair recruitment or retention of subjects in longer-term studies. Linear mixed-models regression revealed that walking improved psychological state when compared to activities of daily living, regardless of walk environment (p &lt, 0.05). Comparison of mean differences showed that forest walks yielded the largest and most consistent improvements in psychological state. Thus, despite a protocol that required a 3.5 h time commitment per laboratory visit, the beneficial effects of walking and exposure to a forested environment were observed.

Although it has been believed that brown adipose tissue (BAT) depots disappear shortly after the perinatal period in humans, PET imaging using the glucose analog 18F-FDG has shown unequivocally the existence of functional BAT in adult humans, suggesting that many humans retain some functional BAT past infancy. The objective of this study was to determine to what extent BAT thermogenesis is activated in adults during cold stress and to establish the relationship between BAT oxidative metabolism and 18F-FDG tracer uptake. Methods: Twenty-five healthy adults (15 women and 10 men; mean age ± SD, 30 ± 7 y) underwent triple-oxygen scans (H215O, C15O, and 15O2) as well as measurements of daily energy expenditure (DEE; kcal/d) both at rest and after exposure to mild cold (15.5°C [60°F]) using indirect calorimetry. The subjects were divided into 2 groups (high BAT and low BAT) based on the presence or absence of 18F-FDG tracer uptake (standardized uptake value [SUV] > 2) in cervical–supraclavicular BAT. Blood flow and oxygen extraction fraction (OEF) were calculated from dynamic PET scans at the location of BAT, muscle, and white adipose tissue. Regional blood oxygen saturation was determined by near-infrared spectroscopy. The total energy expenditure during rest and mild cold stress was measured by indirect calorimetry. Tissue-level metabolic rate of oxygen (MRO2) in BAT was determined and used to calculate the contribution of activated BAT to DEE. Results: The mass of activated BAT was 59.1 ± 17.5 g (range, 32–85 g) in the high-BAT group (8 women and 1 man; mean age, 29.6 ± 5.5 y) and 2.2 ± 3.6 g (range, 0–9.3 g) in the low-BAT group (9 men and 7 women; mean age, 31.4 ± 10 y). Corresponding maximal SUVs were significantly higher in the high-BAT group than in the low-BAT group (10.7 ± 3.9 vs. 2.1 ± 0.7, P = 0.01). Blood flow values were significantly higher in the high-BAT group than in the low-BAT group for BAT (12.9 ± 4.1 vs. 5.9 ± 2.2 mL/100 g/min, P = 0.03) and white adipose tissue (7.2 ± 3.4 vs. 5.7 ± 2.3 mL/100 g/min, P = 0.03) but were similar for muscle (4.4 ± 1.9 vs. 3.9 ± 1.7 mL/100 g/min). Moreover, OEF in BAT was similar in the 2 groups (0.51 ± 0.17 in high-BAT group vs. 0.47 ± 0.18 in low-BAT group, P = 0.39). During mild cold stress, calculated MRO2 values in BAT increased from 0.97 ± 0.53 to 1.42 ± 0.68 mL/100 g/min (P = 0.04) in the high-BAT group and were significantly higher than those determined in the low-BAT group (0.40 ± 0.28 vs. 0.51 ± 0.23, P = 0.67). The increase in DEE associated with BAT oxidative metabolism was highly variable in the high-BAT group, with an average of 3.2 ± 2.4 kcal/d (range, 1.9–4.6 kcal/d) at rest, and increased to 6.3 ± 3.5 kcal/d (range, 4.0–9.9 kcal/d) during exposure to mild cold. Although BAT accounted for only a small fraction of the cold-induced increase in DEE, such increases were not observed in subjects lacking BAT. Conclusion: Mild cold-induced thermogenesis in BAT accounts for 15–25 kcal/d in subjects with relatively large BAT depots. Thus, although the presence of active BAT is correlated with cold-induced energy expenditure, direct measurement of MRO2 indicates that BAT is a minor source of thermogenesis in humans.

Unidad de excelencia María de Maeztu MdM-2015-0552 Objectives:We assessed associations between child stunting, recovery, and faltering with schooling and human capital skills in a native Amazonian society of horticulturalists-foragers (Tsimane'). - Methods: We used cross-sectional data (2008) from 1262 children aged 6 to 16 years in 53 villages to assess contemporaneous associations between three height categories: stunted (height-for-age Z score, HAZ-1), and three categories of human capital: completed grades of schooling, test-based academic skills (math, reading, writing), and local plant knowledge. We used annual longitudinal data (2002-2010) from all children (n = 853) in 13 villages to estimate the association between changes in height categories between the first and last years of measure and schooling and academic skills. - Results: Stunting was associated with 0.4 fewer completed grades of schooling (∼24% less) and with 13-15% lower probability of showing any writing or math skills. Moderate stunting was associated with ∼20% lower scores in local plant knowledge and 9% lower probability of showing writing skills, but was not associated with schooling or math and writing skills. Compared with nonstunted children, children who became stunted had 18-21% and 15-21% lower probabilities of showing math and writing skills, and stunted children had 0.4 fewer completed grades of schooling. Stunted children who recovered showed human capital outcomes that were indistinguishable from nonstunted children. Conclusions: The results confirm adverse associations between child stunting and human capital skills. Predictors of growth recovery and faltering can affect human capital outcomes, even in a remote, economically self-sufficient society.

Objective: Recent work in rodents has demonstrated that basal activity of local sympathetic nervous system is critical for maintaining brown adipocyte phenotypes in classic brown (BAT) and white adipose tissue (WAT). Accordingly, we sought to assess the relationship between sympathetic innervation and cold-induced activation of BAT and WAT, and its relation to local and whole body daily energy expenditure (DEE, kcal/d) in lean young adults. Methods: Twenty adult lean normal subjects (10F/10M, 23.3 + 3.8 years, BMI = 23.7 + 2.5) underwent 11C-meta-hydroxyephedrin (HED) and 15O-water PET imaging at rest and following exposure to mild cold (16oC) temperature. In addition, 18F-fluorodeoxyglucose (FDG) images were obtained during the cold stress condition to assess cold-activated BAT mass. Subjects were divided into two groups (High-BAT, Low-BAT) based on the presence of FDG tracer uptake (SUV > 2) in supraclavicular BAT (-150 < HU < -50). Blood flow and HED retention index (RI, an indirect measure of sympathetic innervation) were calculated from dynamic PET scans at the location of BAT, WAT, muscle and visceral WAT. Whole body DEE during rest and cold stress was measured by indirect calorimetry. Tissue level oxygen consumption (MRO2) in BAT was determined and used to calculate the contribution of cold-activated BAT and WAT to daily DEE. Results: FDG uptake identified subjects with high and low levels of cold-activated BAT mass (High-BAT, 96 + 37g; Low-BAT 16 + 4g). HED RI under thermoneutral conditions significantly predicted FDG uptake during cold stress (R2 = 0.68, p

Objectives Among indigenous circumpolar populations, extreme seasonality influences food availability and energy metabolism. Furthermore, subsistence patterns and wage labor opportunities shift with season. Thus, health measures among circumpolar populations likely exhibit seasonal changes that are influenced by lifestyle factors. This study examines how markers of cardio-metabolic health vary between summer and winter as a function of an individual's lifestyle and sex among the Yakut of northeastern Siberia. Methods Anthropometric dimensions, serum lipids and glucose levels, blood pressure, and lifestyle data were collected for a sample of 115 Yakut participants (71 women, 44 men) in Berdygestiakh, Sakha Republic, Russia in the summer of 2009 and winter of 2011. Results Men and women experienced significant increases in total and HDL cholesterol and triglyceride levels from summer to winter. Women exhibited winter-time increases in adiposity and glucose levels. Men who reported greater market integration were more likely to have lower winter blood pressure levels. Additionally, time spent fishing was associated with lower winter-time LDL cholesterol, while foraging time was associated with higher HDL cholesterol. Conclusions While seasonal changes in anthropometric dimensions were modest, Yakut men and women experienced significant increases in total cholesterol and HDL cholesterol from summer to winter. These results also suggest that while Yakut individuals with greater subsistence participation are more buffered from adverse seasonal changes in cholesterol levels, they may be at a greater risk for winter increases in blood pressure. Furthermore, the interactions between lifestyle and seasonal change in metabolic health appear to differ between Yakut women and men. Am. J. Hum. Biol. 28:868–878, 2016. © 2016Wiley Periodicals, Inc.

Drawing on stories and statistics from the first national study of intersex, this book argues for a distinct framework to address intersex issues and identity, foregrounding people with intersex variations’ own goals, perspectives and experiences. Overview Sex is complex. Humans are simultaneously more similar in their sex development, and more diverse, than is commonly appreciated or understood. Females and males are not made of wildly different ingredients. The potential to have intersex variations—to be born with atypical sex characteristics—exists for all humans in the first few weeks of their prenatal development. 1.7% of people actually go on to be born intersex. However, most of us know little about intersex variations. This is only partly due to their occasional invisibility. Intersex people have historically faced deep social stigma—the assumption that they were simply bizarre aberrations from the human norm. Furthermore, intersex infants have been widely subjected to systematic institutional mistreatment, particularly within medical settings. Finally, some people with intersex variations have simply tried to integrate themselves unnoticed into the socially accepted categories of male and female. Drawing on stories and statistics from the first national study of intersex the book argues for a distinct ‘Intersex Studies’ framework to address intersex issues and identity—foregrounding people with intersex variations’ own goals, perspectives and experiences. Collected in 2015 and arranged in thematic chapters, the data presented here on 272 individuals gives a penetrating account of historically and socially obscured experience. This book is an important and long-overdue contribution to our understanding of human sexuality and a must-read for people with intersex variations, health practitioners, psychologists, advocacy groups, students, and anybody interested in knowing more about our diverse human make-up.

Over the last decades, native Amazonians have put increasing pressure on animal wildlife owing to growth in demand. Across societies, household monetary income and wealth shape food consumption; hence, so it is natural to ask what effect might these variables have on the demand for wildlife consumption among native Amazonians, particularly as they gain a stronger foothold in the market economy and increasing de jure stewardship over their territories. Prior estimates of the effects of household monetary income and household wealth on wildlife consumption among native Amazonians have relied on cross-sectional data and produced unclear results. The goal of this research was to improve the precision of previous estimates by drawing on a larger sample and on longitudinal data. The analysis draws on a dataset composed of five consecutive annual surveys (2002–2006, inclusive) from 324 households in a native Amazonian society of foragers and farmers in Bolivia (Tsimane'). Multiple regression analysis is used to estimate the association between wildlife consumption and monetary income and wealth. Wildlife consumption bore a positive association with the level of household wealth and no significant association with household monetary income. Among Tsimane', the main internal threat to wildlife conservation in the short run will likely arise from increases in wealth, probably from the enhanced capacity that selected physical assets (e.g. guns) have in the capture of animal wildlife

Objectives. This study investigated the lifestyle and anthropometric correlates of impaired fastingglucose and the presence of metabolic syndrome (MetS) among an Indigenous high-latitude herdingpopulation from north-eastern Siberia.Study Design. Cross-sectional study of Yakut (Sakha) adult volunteers.Methods. We collected health, lifestyle and anthropometric data among 166 Yakut adults (≥18years old; 101 females, 65 males) from the rural village of Tyungyulyu (62°N, 130°E; population2,500), Sakha Republic (Yakutia), Russia. Measurements of fasting glucose, triglycerides, HDLcholesterol, blood pressure and waist circumference were used to document the presence of MetSbased on the updated Adult Treatment Panel (ATP) III definition.Results. Metabolic syndrome was relatively uncommon among study participants, with only 10%of participants classified as having MetS, including 8% of females and 12% of males. Elevatedblood pressure and low HDL cholesterol were the most common features of MetS in Yakut men andwomen, while elevated fasting glucose and high triglycerides were uncommon in both sexes. Relativelylow mean fasting glucose concentrations were documented among Yakut women (4.46±0.65mmol/L) and men (4.41±0.76 mmol/L); no participants were classified as diabetic.Conclusions. Fasting glucose and MetS are at relatively low levels in this population; however,rising rates of obesity are likely to lead to future increases in MetS and impaired fasting glucose inthis population. Further, increasing consumption of market foods, many high in refined sugars, islikely to contribute to an increased presence of impaired fasting glucose and MetS. (Int J Circumpolar Health 2010; 69(1):87–98) Keywords: cardiovascular disease, diabetes, obesity, anthropometry, market integration, Russia

In this article, we argue for the increased use of panel data in cultural anthropology. Panel data, or repeated measures from the same units of observation at different times, have proliferated across the social sciences, with the exception of anthropology. The lack of panel data in anthropology is puzzling since panel data are well-suited for analyzing continuity and change—central concerns of anthropological theory. Panel data also establish temporal order in causal analysis and potentially improve the reliability and accuracy of measurement. We review how researchers in anthropology and neighboring disciplines have dealt with the unique challenges of collecting panel data and draw lessons for minimizing the adverse consequences of measurement error, for reducing attrition, and for ensuring continuity in management, archiving, documentation, financing, and leadership. We argue that increased use of panel data has the potential to advance empirical knowledge and contribute to anthropological theory.

The modeling of cultural transmission is of great importance for understanding the maintenance, erosion, and spread of cultural traits and innovations. Researchers have hypothesized that, unlike biological transmission, cultural transmission occurs through at least three different, non-mutually exclusive paths: (1) from parents (vertical); (2) from age peers (horizontal); and (3) from older generations (oblique). We used data from 270 adults in a society in the Bolivian Amazon to estimate the association between a person's knowledge and skills and the knowledge and skills of the (1) same-sex parent, (2) age peers (or individuals born in the same village as the subject within ±4 years of the subject's year of birth), and (3) parental cohort (excluding parents). We found a statistically significant association between personal and parental and old cohort knowledge. The magnitude of the association is larger for old cohort knowledge than for parental knowledge, suggesting that, for the studied population, the transmission of ethnobotanical knowledge and skills is mostly oblique.

The Amazon rain forest harbors some of the world's richest biological diversity. During the twentieth century, two types of actors cleared that forest: native Amazonians and outside encroachers. Of the two actors, we know more about what drives outside encroachers to clear forest than about what drives native Amazonians to clear forest. The past research focus has served well because during the twentieth century outside encroachers cleared most of the Amazonian forest. But the past research focus needs to be expanded because native Amazonians are claiming de jure stewardship of the forests they inhabit, and with tighter jurisdiction over those forests will likely come changes in the amount of forest native Amazonians clear. Prior research in rural areas of low-income nations suggests that household income affects household forest clearance. To estimate the effects of household real income on the total forest area (old-growth + fallow) cleared by households we use a panel composed of five annual household surveys (2002–2006, inclusive) from 324 households of a native Amazonian society in Bolivia (Tsimane'). We control for household and village fixed effects and use an instrumental variable for household income. We find positive and significant household real income elasticities of forest clearance of 0.35 and 0.47 and an increase in forest clearance of 5.3%/year. The main finding stood up well to sensitivity analysis. These estimates suggest that in the near future, the forest in the Tsimane' territory will likely face increasing pressure from the Tsimane' themselves, not just from outside encroachers

Anthropologists, conservation biologists, and psychologists have generally found a long-term (secular) decline of ethnobotanical knowledge among indigenous people. To estimate such knowledge loss, researchers have typically relied on a single cross-sectional data set to (a) measure knowledge among people of different ages, (b) compare measures between ages, and (c) infer a loss of knowledge if the old knew more than the young. We improve on the approach by simultaneously controlling for cohort effects and age effects—the first refers to the effect of the birth period and the second refers to the effect of the life cycle (or aging). Failure to simultaneously control for both effects may produce the misleading impression that the old know more than the young, and the conclusion that the difference reflects a secular loss of knowledge when in fact it may reflect different positions in the life cycle. We use data collected during 2005 from a native Amazonian society of foragers-farmers in Bolivia (Tsimane') t...

Research suggests that cash cropping is positively associated with deforestation. We use three-year data (2000-2002, inclusive) from 493 households to estimate the association between cash cropping rice and deforestation. Doubling the area sown with rice is associated with a 26-30 percent increase in the area of forest cleared during the next cropping season. We simulate the changes in rice cultivation to reach a daily income level of $1/person from cash cropping rice. We find that within 10 years: (1) the amount of deforestation would triple, (2) work requirements would exceed household's labor availability, and (3) fallows duration would decrease two-fold. To avoid the increase of deforestation from cash cropping requires increasing productivity, diversification of income sources, or both.

Crop diversity protects food consumption in poor households within developing nations. Here we estimate the association between crop diversity on swidden fields and ethnobotanical knowledge. We conducted research among 215 male household heads from a native Amazonian society. Using multivariate regressions, we found higher crop diversity among households that depend on agricultural production for household consumption. We also found a statistically significant and positive, but low, association between the ethnobotanical knowledge of the male household head and crop diversity. Doubling the stock of ethnobotanical knowledge of the male household head is associated with a 9% increase in the number of crops sown by a household. The association remained after we controlled for the household level of market exposure, but vanished after we controlled for the social capital of the male household head. Future research should compare the association between ethnobotanical knowledge and crop diversity across different agricultural systems (i.e., home gardens, fallow fields).

The Yakuts are a Turkic-speaking population of northeastern Siberia and based on archaeological and ethnohistorical evidence are believed to have originated from Turkic populations in south Siberia. To investigate this model, the HVS-I of the mitochondrial DNA control region was sequenced for 144 Yakut individuals representing seven communities from central Yakutia and compared to HVS-I data for other Asian populations. Haplogroups C and D comprise 75.7% of the Yakut sample, with only 9.7% assigned to west Eurasian lineages. The Ewens-Watterson homozygosity test revealed a significant deviation ( P = 0.045) in the observed frequencies of common haplotypes relative to the expected values, indicating the genetic effects of a founder event. This is supported by a fragmented MJ network dominated by high-frequency haplotypes within haplogroups C and D. Nested cladistic analysis identified subhaplogroup D5a as the product of a long distance colonization event and potential founder lineage for the Yakuts, dating to approximately 1,630 years BP. SAMOVA analyses and MDS plot of genetic distances show close genetic affinities between the Yakuts and south Siberian populations, and thus affirming the south origin model.

Among linguistic minorities of industrial nations proficiency speaking the dominant national language increases earnings and wages, but do similar results apply to autarkic linguistic minorities of developing nations? We contribute to studies of the returns to language skills by applying the human-capital approach to a society of hunters, gatherers, and farmers in the Bolivian Amazon (Tsimane’). We use a panel consisting of five consecutive quarters to: (a) estimate the returns to language skills while controlling for schooling, math and writing skills, and other confounders and (b) explore the paths through which language skills might affect earnings. Fluent speakers of Spanish and the local language earned 36.9–46.9% more than monolingual speakers of the local language. Moderate fluency in Spanish bore no strong association with earnings. Spanish-Tsimane’ bilingualism bore a positive association with earnings partly because bilingualism bore a positive association with credit access, use of modern production technologies, and labor productivity.

Because social capital shapes many desirable socioeconomic outcomes, we ask what incentives drive private investments in social capital. We estimate the association between private investments in social capital (outcome variable) and the following explanatory variables: (a) individual-level variables from an optimal investment model, (b) spillovers from group social capital, (c) village income inequality, and (d) market openness. We draw on information from Tsimane’, a native Amazonian society of foragers and farmers in Bolivia, and equate social capital with gifts, help given, and communal labor offered by the household. Age bore an inverted U-shaped and income bore a positive association with social capital, but geographic mobility, wealth, and schooling bore no significant association with social capital. We found strong group-level associations even after instrumenting social capital; the association probably stems from strong kinship ties which tend to blur the line between the group and the individual. Village measures of social capital were positively and significantly associated with private investments in social capital. We found some evidence that village income inequality and market openness were negatively associated with private investments in social capital.