Understanding Growth and Malnutrition in Baka Pygmy Children

We determined stunting, wasting, and obesity frequencies in a total 1092 2-to-12 year old Baka Pygmy children from anthropometric and health data gathered in 34 villages in the Djoum-Mintom region in southeastern Cameroon in four health campaigns in 2010 and 2017–9. We compare these to the WHO Child Growth Standards, Amazonian Tsiname growth references for inter-population comparisons and the study population itself. Population-specific growth charts were constructed using GAMLSS modelling. Our results show that Baka children have one of the highest global rates of stunting relative to the WHO child growth standard with 57.8% for 2-to-12 year olds and 64% and 73% for 2-to-4 year old girls and boys, respectively. Frequencies of wasting, overweight, and low BMI were low at 3.4%, 4.6% and 4.3%, respectively, for 2-to-12 year olds. Underweight was at 25.5%, in the upper range for sub-Saharan Africa. Edemas indicated rare severe malnutrition (0.3%). Uncertainties in age estimation had dramatic effects on the reliability of estimated individual z-scores but distributions of z-scores were robust at a population level. In the context of the recent evidence for genetic adaptation of the Pygmies’ small stature to the tropical forest environment we argue that WHO child standards for weight and BMI are applicable. However, standards for height are clearly not adequate for Pygmy people. To achieve UN Sustainable Development Goals, we recommend that Pygmy specific growth standards are developed for the various, genetically differing Pygmy tribes

Evolutionary perspectives on human height variation

Human height is a highly variable trait, both within and between populations, has a high heritability, and influences the manner in which people behave and are treated in society. Although we know much about human height, this information has rarely been brought together in a comprehensive, systematic fashion. Here, we present a synthetic review of the literature on human height from an explicit evolutionary perspective, addressing its phylogenetic history, development, and environmental and genetic influences on growth and stature. In addition to presenting evidence to suggest the past action of natural selection on human height, we also assess the evidence that natural and sexual selection continues to act on height in contemporary populations. Although there is clear evidence to suggest that selection acts on height, mainly through life-history processes but perhaps also directly, it is also apparent that methodological factors reduce the confidence with which such inferences can be drawn, and there remain surprising gaps in our knowledge. The inability to draw firm conclusions about the adaptiveness of such a highly visible and easily measured trait suggests we should show an appropriate degree of caution when dealing with other human traits in evolutionary perspective.</p

Wild Meat

The meat of wild animals is a crucial part of the diets of millions of families in the tropics and subtropics. It is often the most accessible and sustainable source of protein and micronutrients and can also be a significant source of revenue for many people. Enabling these people, mostly the poor, to continue consuming wildlife in a sustainable manner — while reducing the impacts of overhunting on animal populations — are the main challenges facing researchers and policymakers. Since 2011, the research and policy initiatives led by the Bushmeat Research Initiative (the BRI-CIFOR team), in conjunction with many partners and collaborators worldwide, have made substantial contributions to this topic. These efforts increase the understanding of the current levels and trends of wild meat extraction and of the importance of this wild meat to consumers. The BRI-CIFOR team has generated important new data of wild meat use across a diverse number of environments worldwide. This publication presents some of the key FTA outputs on wild meat; over the last decade these efforts have contributed to inform science, policy and practice

Gorillas and Grandfathers: Baka hunter-gatherer conceptions of the forest and its protection, and the implementation of biocultural conservation through Extreme Citizen Science in the rainforests of Cameroon

South-eastern Cameroon is an area of high biocultural diversity, where gorillas, forest spirits, and people live side-by-side. Rapid degradation of this diversity is also a reality, a result of lying on a frontier of aggressive capitalist expansion and top-down conservation interventions. It is a zone of conflict where values, ontologies, priorities and identities clash, informing how the landscape is used and by whom. Whilst a range of actors work in managing these forests, some more sensitive to community needs and concerns than others, no one is genuinely engaging with forest communities to understand what conservation means to them and what their solutions are. Baka hunter-gatherers are at heart of this: forest managers do not consult the Baka and do not know how to engage with them. This problem-based thesis aims to transcend disciplinary boundaries to examine what values and conceptions are held by the Baka and other actors living in and managing the rainforest south of the Dja Biosphere Reserve in relation to the forest and its conservation, and presents the results of two projects which attempt to put biocultural conservation grounded in community values into practice. The work attempts this through firstly focusing on one Baka village – Kémà – endeavouring to understand the socio-ecological relationship between the Baka of Kémà and the forest through extensive ethnographic fieldwork. This subsequently grows into an exploration of what ‘protecting’ the forest means to such communities, and what conservation looks like through their eyes, relating this to concepts of biocultural conservation. Secondly, I expand this to those who manage the forest to gauge their values towards the forest and their vision of its conservation, comparing these to my findings in Kémà. And thirdly, building on biocultural approaches to conservation under the approach of ‘Extreme Citizen Science’, I describe and evaluate two participatory mapping and reporting projects I co-created alongside community members which demonstrate the possibility of building conservation initiatives led by communities themselves and founded upon such socio-ecological relationships and priorities as those that emerge throughout the thesis

Social structure and knowledge sharing networks in hunter-gatherers: A case study on the plant knowledge of the Mbendjele BaYaka Pygmies

Hunters and gatherers occupied 95% of the human history. Despite the forces of globalization, current-day hunter-gatherers can shed light on how we adapted to different environments and generated complex cultural traits. Their changing ways of life, on the other hand, may let us understand cultural change. In this thesis, I explore the cultural evolution of plant knowledge in an extant hunter-gatherer population, the Mbendjele BaYaka Pygmies from the Northern Republic of Congo. In Chapter 4, I show that the Mbendjele use wild plants for various reasons from treating digestive system disorders to punishing norm violators. In Chapter 5, I investigate whether there are adaptive benefits to the use of certain medicinal plants and explore the common uses of medicinal plants across different Pygmy populations and great apes. I also explore the known bioactive compounds, and test the effects of mothers’ use of certain medicinal plants on their children’s body- mass-index. In Chapter 6, I investigate how the Mbendjele have evolved such a rich plant use repertoire by exploring sharing of medicinal and non-medicinal plant knowledge with respect to features of social structure. I argue that the long-term pair bonds, marital ties and cooperative breeding have allowed the Mbendjele to combine and accumulate rich medicinal plant uses. Additionally, co-residence of multiple families provides a context for the sharing and accumulation of plant uses that concern cooperative foraging and social norms. In Chapter 7, I explore the socioeconomic transitions in the Mbendjele that live in a logging town and examine how plant knowledge declines with their changing life-style. I argue that change in subsistence activities, emerging inequalities and decreased mobility hinder the transmission of traditional knowledge. Nevertheless, I argue that adoption of new cultural traits may be inevitable and beneficial for the resilience of modern day hunter-gatherers

Dental development in a South African sub adult population: determination of reference values for permanent tooth formation and emergence

A thesis submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the Degree of Doctor of Philosophy in Medicine. October 2017.Background: Population-based knowledge of human biological growth and development processes is fundamental for assessing the health status of a community. This requires an understanding of the growth pattern for the children as well as the environmental stresses that disrupt or impede their growth. These stresses are usually easy to identify, but data on normal development and growth variation in most populations is surprisingly lacking. Instead, researchers typically compare growth in the population of interest to references formulated for European or US children. The problems associated with using non-population specific references are complex, and their application can lead to misrepresentations of the health status. In addition, the influence of environmental factors on dental development is still debated and the relationship of dental development with life history events, such as sexual maturity, is unclear. Aim: The aim of this study is to develop population-specific reference for permanent tooth formation and emergence among Black Southern Africans, to compare this reference with other population references, and to investigate the influence of sex and nutritional status on dental development. Method: Study design and population This is a cross sectional study. A total of 642 children comprising of 270 males and 372 females from primary and secondary schools were recruited over one and half years. Only participants whose parents and grandparents are indigenous Southern Africans were included. Participants were screened in a mobile dental truck fitted with digital panoramic x ray. Systematic Review A literature search of PubMed, Scopus, Ovid, Database of Open Access Journals and Google Scholar was undertaken. All eligible studies published before December 28, 2016 were reviewed and analyzed. Meta-analysis was performed on 28 published articles using the Demirjian and/or Willems methods to estimate chronological age. The weighted mean difference at 95% confidence interval was used to assess accuracies of the two methods in predicting the chronological age of children. Tooth formation in Southern Africa To investigate tooth formation, all the 642 Black Southern African children comprising of 270 males and 372 females were recruited. The panoramic radiograph of each child was analysed and the dental maturity score of the left mandibular permanent teeth was obtained according to the Demirjian et al. (1973) method. The dental maturity score of each child was converted to dental age using standard tables and percentiles curves for both sexes by Demirjian et al. (1973). The ages of attainment of specific maturity stages were calculated with pr obit analysis and compared by sex and population. Comparisons of age estimation methods For comparison of the common methods used in estimation of age, 540 children (233 males and 307 females out of the 642 children were recruited. This is because all the children aged 16 years and above have reached 100% maturity and hence excluded from the study. Panoramic radiographs of the children were analyzed and the dental maturity scores of the left mandibular permanent teeth were calculated according to the Demirjian et al. (1973), Demirjian and Goldstein (1976) and Willems et al (2001) methods. The dental maturity scores were converted to dental ages using standard tables and percentiles curves for males and females (Demirjian et al. 1973; Demirjian and Goldstein 1976; Willems et al. 2001). The dental ages obtained were compared to the chronological ages of the children and the mean differences obtained by the three methods compared. Nutrition and tooth formation Effect of nutrition on tooth formation was investigated on all the 642 Black Southern African children comprising of 270 males and 372 females were recruited. The Panoramic radiograph of each child was analysed using the Demirjian et al. (1973) method. The dental maturity score of each child was converted to dental age using standard tables and percentiles curves for both males and females by Demirjian et al. (1973). In addition, measures of nutritional status such as, height, weight, mid upper arm circumference and head circumference were obtained from the children. The timing, sequence of emergence and the effect of nutrition on tooth emergence To investigate tooth emergence and the influence of nutritional status on emergence, information on type of teeth and number of teeth emerged were collected from 639 (266 males and 373 females) Black Southern African children aged 5-20 years out of the total 642 children because the emergence data for 3 children were found to be incomplete. An emerged tooth was defined as a tooth with any part of its crown penetrating the gingiva and visible in the oral cavity. Height, weight, mid upper arm circumference and head circumference of the participants were measured. Children with any form of tooth impaction and agenesis were excluded from the study. Life history events and dental development To determine the association between tooth development and life history variables, mean ages of attainment of sexual maturity stages were adapted from Lundeen et al. (2015) and Norris and Richter (2005) to identify if any stage of dental development co-occured with life history events. Southern Africa specific reference values The WITS Atlas was developed using the tooth formation stage with the highest frequency for each tooth. This stage was considered the developmental reference for an age cohort. Southern African tables of conversion of maturity scores were generated separately for males and females using polynomial regression functions (3rd degree). Maturity curves were plotted to determine the dental maturity curves for each sex. The Southern African specific tables of conversion of maturity score were tested on 540 participants aged 5 to 15.99 years and the results compared to the Willems and Demirjian methods of age estimation. Data were analysed with Stata 12 for Windows. The analysis included frequencies and cross-tabulations. Associations between categorical variables were tested with chi square while those between continuous variables were tested with Student’s t-tests. The mean ages of emergence and standard deviation were computed using probit analysis. Sex and population comparisons were done using Student’s t-tests. The height and BMI were converted to z-scores using WHO z-scores for age tables (WHO 1995). A cut-off z-score of ≤−2 for BMI/height was used to place children into underweight/short for age, ≥-2 to 2.0 for normal, and ≥2 for overweight/obese/tall for age categories. Mean age of emergence and mean age of attainment of maturity stages were calculated for each tooth using these BMI subdivisions. Analysis of variance (ANOVA) and Games-Howell were used to determine the differences between the BMI/height subdivisions. A Student’s t-test was used to compare any two means whenever one of the three subdivisions of BMI did not yield a mean age of emergence. Spearman’s rho correlations between total number of teeth, dental maturity scores and anthropometric variables were done. A Shapiro-Wilk W test showed that the dependent variables (total number of teeth emerged and dental maturity) and the predictor variables were not normally distributed. Therefore, a generalized linear model (negative binomial) was used with the number of emerged teeth/dental maturity modelled as the dependent variable and anthropometric variables and age as predictors. Adequacy of fit was checked using the deviance residuals as recommended by McCullagh and Nelder (1989). The deviance residuals showed that it was normally distributed and the plot of the residuals against each of the covariates also showed model fit. As expected, the collinearity test showed that BMI, height and weight were significantly collinear. When these variables were excluded from the model, there was no difference in the values of the output. Hence, the variables were included in the final model for generalized linear regression analysis. The model was built using forward selection. Statistical significance was inferred at p<0.05. Results: Systematic review Meta-analysis revealed that the Willems method has better accuracy globally compared with the Demirjian method. Dental maturity in Black Southern Africans The females show advanced dental maturity and dental ages compared to males (p<0.05). Cross-population comparison shows the Southern African females are advanced in dental maturity compared to European and Asian children. Comparison of methods for estimating dental age The Original Demirjian method significantly overestimated the age of the males by 0.85 years and the females by 1.0 years (p<0.05) with the same mean absolute error of 1.1 years for both sexes. Similarly, the Modified Demirjian method significantly overestimated chronological ages of males (0.90 years) and females (1.21 years) with the highest mean absolute error of 1.1 years and 1.4 years for males and females respectively. The Willems method had the lowest, but still significant mean differences (0.2 years for males and 0.3 years for females) between the dental age and chronological age. It also demonstrated the least mean absolute errors for males (0.70 years) and females (0.68 years). Nutrition and tooth formation Significant advancements were found in the age of attainment of H stage for all the permanent teeth in the overweight group compared to the underweight group (p<0.05). Negative binomial regression analysis indicates that age, height, and BMI are significant predictors of the dental maturity score for males (p<0.05), while age, height, weight, BMI and head circumference are significant predictors of the dental maturity score for females. Tooth emergence Females have all the permanent teeth emerged earlier than males except for the third molars (p<0.05). Generally, Black Southern African children have similar ages and sequence of emergence as children from other sub-Saharan Africa countries. Black Southern African children have earlier mean ages of emergence of permanent teeth compared to children from the USA, Europe, Australia and Asia. Sexual dimorphism was noted in the sequence of emergence of I1/M1 in the mandible with the females having the M1I1 sequence as opposed to I1MI in males. The sequence of emergence of Southern African males is similar in both jaws to males from the USA and Europe but differs from Iranians and Pakistanis. Females show similar patterns of sequence with sub-Saharan African, Australian and US females in the maxilla. They display MI/I1 variation in the mandible. Nutrition and tooth emergence Overweight/obese children generally show significantly earlier emergence times compared to normal weight/severely underweight children (p<0.05). Females and tall children have more emerged teeth than shorter children when corrected for age and sex (p<0.05). The generalized linear regression model (negative binomial) shows that height, weight and BMI have significant associations with the number of emerged teeth (p<0.05). Dental development and life history variables The number of teeth emerged in males correlate strongly with chronological age (r=0.91, p=0.00) and height (r=0.89, p=0.00), moderately with mid-upper arm circumference (r=0.61, p=0.00) and weakly with head circumference (r=0.16, p=0.00). In females, the number of teeth emerged correlates strongly with chronological age (r=0.88, p=0.00) and height (r=0.83, p=0.00), moderately with mid-upper arm circumference (r=0.59, p=0.00), and weakly with head circumference (r=0.38, p=0.00). Similar patterns of correlation are found for dental maturity. The emergence of the maxillary and mandibular M2s co-occurs with the G2 stage of gonad development and the PH2 stage of pubic hair development in males. The M2s emerge coincident with the attainment of Tanner’s B2 breast stage and the PH2 pubic hair stage in females. The age of menarche does not coincide with any of the determined ages for emergence of teeth. Attainment of the H stage of development in the C1 co-occurs with the G2 stage of gonad development and shortly after the pubic hair stage PH2 in the males. In females, the attainment of the H stage of C1 formation occurs shortly before the attainment of the B2 stage of breast development. Furthermore, the H stage of P1 formation coincides with the PH2 stage of pubic hair development, shortly after the attainment of the stage B2 of breast development. The attainment of the H stage in P2 formation coincides with the age of menarche at approximately 13 years. Southern African specific reference A new dental atlas (WITS Atlas) was developed due to the significantly earlier ages of emergence and formation among Black Southern Africans. When compared to the London atlas, the canines, premolars and second molars are at least a year ahead in the WITS Atlas. Third molar formation and emergence occurs three years earlier in the WITS Atlas. Polynomial regression formulae were generated and Southern African specific conversion tables were generated for the males and females. The new tables of maturity scores show no overestimation of the chronological ages of males (0.045, p>0.05) and females (0.08, p>0.05). Compared to the Willems and Demirjian methods, the Southern African specific maturity tables showed the least mean absolute error for both sexes. Conclusion: There is sexual dimorphism in the timing of tooth emergence with females having earlier emergence times. Black Southern Africans show similarities in the ages and sequence of emergence of the permanent teeth with children from other sub-Saharan African countries but, they are advanced relative to children from the USA, Europe, Australia and Asia. Similarly, the Black Southern African children show advanced tooth formation compared to children from Europe, Asia and Australia. The Willems method is more accurate at estimating chronological age for forensic and anthropological purposes compared to the Demirjian methods that significantly overestimate the chronological age of children. Of the three methods tested on Black Southern African children, the Willems method is the most accurate in estimating chronological age. However; it significantly overestimated the chronological age of Black Southern African children. Hence, there is a need for population-specific reference values for use in the age estimation of Black Southern African children The WITS Atlas and new population-specific maturity tables for Black Southern African males and females were developed. The WITS Atlas differs significantly from the London atlas with earlier ages of tooth formation and emergence. The Southern African specific age estimation method shows good accuracy in the estimation of dental ages. By inference, this method could be used in other sub-Saharan African countries because of similarities in tooth formation and emergence times. Contrary to some studies, nutrition was found to have a significant influence on the number of teeth emerged and the timing of emergence. Obese/overweight/tall children tend to have earlier timing of emergence and more emerged teeth compared to their underweight peers. Similarly, obese/overweight/tall individuals attained the H stage of tooth formation of most teeth earlier than their underweight and normal weight age-mates. Emergence of second molars and the H stage of canine and first premolar formation co-occur with the onset of puberty in males and females. Menarche appears to coincide with the attainment of H stage of the mandibular second premolar.LG201

Development discourse and the Batwa of South West Uganda: representing the 'other' : presenting the 'self'

This thesis focuses on a group of former forest based hunter-gatherers, the Batwa of South West Uganda, whose livelihoods and situations have been dramatically affected through their recent interactions with non-Batwa peoples. Once inhabitants of the rainforests of South West Uganda, the Batwa today live in bonded labour arrangements with their local neighbours and exist as a despised and marginalised group, positioned on the margins of Ugandan society. In the first part of this thesis, Global Powers, I seek to lay out the theoretical foundations for the marginalisation of the Batwa by discussing the more general marginalisation and representation of Indigenous Peoples. In the rest of the thesis, I move on to discuss two specific questions. In the second section, Local Realities, I ask why the Batwa have ended up in their current situation and I investigate the historical and social contexts of the south west of Uganda that have shaped their present predicament. In the third section, Current Interface, I ask why national and international interventions, aimed at helping the Batwa, have failed to achieve their stated aims, and in some circumstances deepened their present marginalisation? The thesis argues that representations of, and knowledge about the Batwa are constructed from an epistemology that seeks to create a subordinate ‘Other’ in order to assert a dominant ‘Self’. As such, their marginalised position replicates the situation of similar ‘Exotic Others’ found throughout the world. Importantly this construction plays a crucial role in the progression and validation of distinct social ontologies that the dominant ‘Modern World’ holds as self evident and true to its own social reality. As a result, the Batwa have only two futures which are presented to them by the dominant forces that regulate their situation. On the one hand, they are coerced to assimilate towards the identity of the dominant ‘Self’ and in doing so cast off the identity which the dominant ‘Self’ has deemed to account for their ‘Otherness’. Or on the other hand, if they choose to maintain those aspects of their identity which identifies them as the ‘Other’, they are ostracised and depicted as unfit for the ‘Modern World’. I conclude this thesis by suggesting that the current predicament of the Batwa has been constructed by external forces and that Development discourse continues to construct this marginalised position. I also conclude that in positioning the Batwa as the ‘Other’, what is being asserted is the identity of a dominant ‘Self’. This relationship between the dominant ‘Self’ and the marginalised ‘Other’, whilst being declared as a distinct and exclusionary relationship, is in fact an intertwined and entangled relationship. Finally, I argue that a fundamental shift in the paradigm of the ‘Modern World’ is needed in order to allow the Batwa, and other Indigenous Peoples, to be seen not as ‘Exotic Others’ but as equal participants in an interconnected world where multiple ways of knowing and being are mutually supported and validated

Abstracts of podium presentations

EAA PODIUM PRESENTATIONS and ISGA PODIUM PRESENTATIONS BEZDANJAČA: OLD RESEARCH, NEW METHODS; XAVANTE: AN EXAMPLE OF INTERDISCIPLINARY FORENSIC RESEARCH OF HUMAN RIGHTS VIOLATION IN INDIGENOUS POPULATIONS; NEW POPULATION SPECIFIC STATURE RECONSTRUCTION FORMULAE FROM MEDIEVAL EGYPT BASED ON LENGTH OF DRY LONG BONES; GORJANI MURDERS: ANTHROPOLOGICAL ANALYSIS OF TRAUMATIC INJURIES FROM A LATE MEDIEVAL SITE; PULP STONES PRESENCE IN MOLARS OF PAST HUMAN POPULATIONS – THE POTENTIAL INFLUENCE OF SELECTED FACTORS; GENETIC INSIGHT IN THE LATE AVAR POPULATION FROM CROATIAN TERRITORY – THE STORY OF SOCIAL ORGANIZATION, ANCESTRY AND ADMIXTURE TOLD BY ANCIENT DNA; GERIATRIC PALEOEPIDEMIOLOGY: SKELETAL MARKERS OF QUALITY OF LIFE IN ELDERLY POPULATION FROM TWO AVAR PERIOD NECROPOLISES (SERBIA); HEALTH STATUS AND SOCIAL ROLE DIFFERENCES AMONG SEXES IN A MODERN ITALIAN ANTHROPOLOGICAL CONTEXT: COMBINING PALEOPATHOLOGICAL, ANTHROPOLOGICAL AND FUNERARY DATA; ... ; TRENDS IN OVERWEIGHT, OBESITY AND SEVERE OBESITY IN BERGEN, NORWAY (2010-2022) USING DATA FROM ROUTINE CHILD HEALTHCARE.; WEIGHT AND BMI DISTRIBUTIONS IN NATURAL OR ‘NON-MODERN’ POPULATIONS; PROBLEMS OF ADOLESCENT HYPERTENSION AND ASSOTIATION WITH BODY FATNESS AND SCREEN TIME; HEALTH OUTCOMES AND THEIR ASSOCIATIONS IN PRETERM SURVIVORS FROM BIRTH TO ADOLESCENCE: A LONGITUDINAL COHORT STUDY;..

Hunting Wildlife in the Tropics and Subtropics

The hunting of wild animals for their meat has been a crucial activity in the evolution of humans. It continues to be an essential source of food and a generator of income for millions of Indigenous and rural communities worldwide. Conservationists rightly fear that excessive hunting of many animal species will cause their demise, as has already happened throughout the Anthropocene. Many species of large mammals and birds have been decimated or annihilated due to overhunting by humans. If such pressures continue, many other species will meet the same fate. Equally, if the use of wildlife resources is to continue by those who depend on it, sustainable practices must be implemented. These communities need to remain or become custodians of the wildlife resources within their lands, for their own well-being as well as for biodiversity in general. This title is also available via Open Access on Cambridge Core