About

I am an Assistant Professor in Anthropology at UCLA with a focus on health and reproductive decision-making. I am the co-director of the Kunene Rural Health and Demography Project, based in rural Namibia, where I have worked since 2016. I am currently the PI of a project, jointly funded by the National Science Foundation and the Social Science Research Council’s Mercury Project, to examine individual, economic, and cultural factors that mediate vaccination decisions in Namibia. My work employs a combination of quantitative and qualitative methods, including anthropometrics, demography, endocrinology, actigraphy, surveys and interviews, and dyadic peer ratings. In combining these methods, I aim to develop a more holistic picture of health behavior.

Research topics

• Sociology
• Political Science
• Social Science
• Epistemology
• Geography
• Demography
• Psychology
• Engineering ethics
• Zoology
• Biology
• Developmental psychology
• Environmental ethics

Selected publications

• No evidence for disassortative mating based on HLA in a small-scale, endogamous population

  eLife · 2026-03-17

  articleOpen access

  Studies dating back several decades have suggested that humans prefer potential mates with dissimilar HLA genotypes. Evidence for actualized disassortative mating based on the human-specific MHC remains inconclusive. For instance, cosmopolitan populations have often exhibited the opposite trend whereby assortative mating at the MHC is observed, indicating that social stratification may overwhelm potential biological mate preferences. However, small-scale, endogamous populations–whose social structures more closely resemble those throughout most of human evolution–have been largely overlooked. Here, we assess HLA dissimilarity among Himba pastoralists from Namibia, where socially accepted concurrency allows individuals to maintain both arranged marital and self-selected (“love match”) partnerships. This provides a rare opportunity to directly test HLA similarity across contrasting partnership types (arranged vs chosen) within the same social system (n = 249 observed partnerships). We find no difference in HLA dissimilarity (neither at the genotype nor protein divergence level) between partnership types, nor in their fitness benefits to potential offspring as assessed via computationally predicted pathogen binding affinities. The effects of the partnership types likewise do not differ from a random, background distribution of 18,487 possible unrelated pairings. Finally, we detect extensive haplotype sharing across the HLA region, suggesting that episodes of fluctuating positive selection may be a stronger force maintaining HLA polymorphism than disassortative mating, even in an evolutionarily relevant social context.

  PublisherDOI

• No evidence for disassortative mating based on HLA in a small-scale, endogamous population

  eLife · 2026-03-17

  articleOpen access

  Studies dating back several decades have suggested that humans prefer potential mates with dissimilar HLA genotypes. Evidence for actualized disassortative mating based on the human-specific MHC remains inconclusive. For instance, cosmopolitan populations have often exhibited the opposite trend whereby assortative mating at the MHC is observed, indicating that social stratification may overwhelm potential biological mate preferences. However, small-scale, endogamous populations–whose social structures more closely resemble those throughout most of human evolution–have been largely overlooked. Here, we assess HLA dissimilarity among Himba pastoralists from Namibia, where socially accepted concurrency allows individuals to maintain both arranged marital and self-selected (“love match”) partnerships. This provides a rare opportunity to directly test HLA similarity across contrasting partnership types (arranged vs chosen) within the same social system (n = 249 observed partnerships). We find no difference in HLA dissimilarity (neither at the genotype nor protein divergence level) between partnership types, nor in their fitness benefits to potential offspring as assessed via computationally predicted pathogen binding affinities. The effects of the partnership types likewise do not differ from a random, background distribution of 18,487 possible unrelated pairings. Finally, we detect extensive haplotype sharing across the HLA region, suggesting that episodes of fluctuating positive selection may be a stronger force maintaining HLA polymorphism than disassortative mating, even in an evolutionarily relevant social context.

  PublisherDOI

• “Better to die trying”: Vaccine perceptions and COVID-19 experiences in rural Namibian pastoralists

  Vaccine · 2025-04-08 · 4 citations

  articleOpen access1st authorCorresponding

  Substantial research indicates that local explanatory models of disease shape heath behaviors. However, less is known regarding how cultural models of disease influence interpretations of vaccines. Vaccination decisions are based around a plethora of social and cultural factors, including beliefs about disease, cultural-historical experiences with healthcare, and recent vaccination experiences. To understand how local interpretations of vaccination influence vaccination-decision making, we explore cultural models of health, vaccine norms, and COVID-19 beliefs and experiences in Himba and Herero pastoralists of the Kunene region of northern Namibia. Mixed sex focus groups were conducted in July and August of 2024 in communities across a rural and peri-urban gradient. Discussion prompts were designed to elicit dialogue on vaccination beliefs, norms, and experiences, as well as their recent experience with COVID-19. Results from these focus groups indicate that there was substantial confusion differentiating vaccinations from other types of injections. For childhood vaccines, immunization is normative and expected. Women were the primary decision-makers for childhood immunization, reflecting the matrilineal bias of Himba and Herero kinship. For adults, while local leaders had some influence interfacing with public health outreach, the decision to get vaccinated was largely a personal one. Beliefs about COVID-19 were interpreted through pre-existing cultural models of illness, and beliefs about the origins of COVID-19 reflected mistrust in international actors. Fears about COVID-19 vaccines were common, particularly concerns about vaccine safety. However, fears of the illness typically overrode fears of the vaccine, and most report receiving the vaccine despite these worries. These results highlight the importance of extending research beyond a knowledge, attitude, practice framework to incorporate local explanatory models and cultural-historical experiences in understanding vaccine-decision making. These features are particularly important in more traditional, rural, and marginalized populations where medical mistrust is common and local explanatory models of disease drive healthcare decision-making.

  PublisherDOI

• Erema po otjindjumba? Highlighting cultural models and knowledge gaps of malaria in rural Namibian pastoralists

  Malaria Journal · 2025-05-07 · 1 citations

  articleOpen access1st authorCorresponding

  BACKGROUND: As Namibia attempts to eradicate locally transmitted cases of malaria, epidemiological strategies, interventions, and outreach require a sound understanding of indigenous knowledge and practice. Research describing local explanatory models of disease can be of value in these efforts by elucidating how disease is interpreted and treated. To understand how perceptions of malaria infection and treatment may influence health-seeking behaviour, cultural models of the disease were explored in two ethnic groups in rural northwest Namibia. METHODS: Mixed-sex focus groups of 4-8 individuals were conducted in the Kunene region of Namibia. All participants were either Himba or Herero and lived between 14 and 57 km of the regional town centre of Opuwo. Discussion prompts were designed to assess knowledge, beliefs, and norms about malaria, including causes, symptoms, treatment, and prevention. RESULTS: Focus groups reported universal difficulty in discrimination between malaria and respiratory infections, the former of which was often only diagnosed at the hospital. Some recognized mosquitoes as the source of malaria, particularly the more formally educated Herero, but all also reported other causes. Notably these causes, including dietary and temperature-based origins, were considered unavoidable. Himba and Herero believed that malaria was infectious person-to-person and incorrectly believed that malaria was most common during the wintertime. Both groups also relied on a number of traditional remedies to alleviate symptoms, which were used as primary treatment, with formal healthcare treatment typically only sought when the illness progressed. CONCLUSIONS: These results highlight significant differences between local cultural models and biomedical ones that could be detrimental to malaria eradication efforts. Kunene pastoralists have limited understanding of the causes of malaria, and beliefs about environmental and dietary causes may undermine attempts at prevention. Seeking healthcare solutions to malaria was normative, but secondary to use of at home traditional remedies. These findings indicate public health outreach and information campaigns are needed, particularly in rural groups with less formal education.

  PublisherOA PDFDOI

• No evidence for disassortative mating based on HLA in a small-scale, endogamous population

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-05-08

  preprintOpen access

  Studies dating back several decades have suggested that humans prefer potential mates with dissimilar HLA genotypes. Evidence for actualized disassortative mating based on the human-specific MHC remains inconclusive. For instance, cosmopolitan populations have often exhibited the opposite trend whereby assortative mating at the MHC is observed, indicating that social stratification may overwhelm potential biological mate preferences. However, small-scale, endogamous populations-whose social structures more closely resemble those throughout most of human evolution-have been largely overlooked. Here, we assess HLA dissimilarity among Himba pastoralists from Namibia, where socially accepted concurrency allows individuals to maintain both arranged marital and self-selected ("love match") partnerships. This provides a rare opportunity to directly test HLA similarity across contrasting partnership types (arranged vs chosen) within the same social system (n = 249 observed partnerships). We find no difference in HLA dissimilarity (neither at the genotype nor protein divergence level) between partnership types, nor in their fitness benefits to potential offspring as assessed via computationally predicted pathogen binding affinities. The effects of the partnership types likewise do not differ from a random, background distribution of 18,487 possible unrelated pairings. Finally, we detect extensive haplotype sharing across the HLA region, suggesting that episodes of fluctuating positive selection may be a stronger force maintaining HLA polymorphism than disassortative mating, even in an evolutionarily relevant social context.

  PublisherOA PDFDOI

• The Role of Medical Mistrust in Vaccination Decisions in Rural, Indigenous Namibian Communities

  Journal of Racial and Ethnic Health Disparities · 2025-04-21 · 3 citations

  article1st authorCorresponding
  PublisherDOI

• Common DNA sequence variation influences epigenetic aging in African populations

  Communications Biology · 2025-11-05 · 1 citations

  articleOpen access

  Aging is associated with genome-wide changes in DNA methylation in humans, facilitating the development of epigenetic age prediction models. However, these models have been trained primarily on European-ancestry individuals and none account for the impact of methylation quantitative trait loci (meQTL). To address these gaps, we analyze the relationships between age, genotype, and CpG methylation in 3 understudied populations: central African Baka (n = 35), southern African ‡Khomani San (n = 52), and southern African Himba (n = 51). We show that published prediction methods yield higher mean errors in these cohorts compared to European-ancestry individuals and find that unaccounted-for DNA sequence variation may be a significant factor underlying this loss of accuracy. We leverage information about the associations between DNA genotype and CpG methylation to develop an age predictor that is minimally influenced by meQTL and show that this model remains accurate across a broad range of genetic backgrounds. Intriguingly, we also find that the older individuals and those with lower epigenetic age acceleration carry more genetic variants linked to reduced epigenetic age. These findings support the hypothesis that multiple heritable factors collectively influence healthspan and longevity in human populations.

  PublisherOA PDFDOI

• Women’s subsistence strategies predict fertility across cultures, but context matters

  Proceedings of the National Academy of Sciences · 2024-02-12 · 16 citations

  articleOpen access

  While it is commonly assumed that farmers have higher, and foragers lower, fertility compared to populations practicing other forms of subsistence, robust supportive evidence is lacking. We tested whether subsistence activities-incorporating market integration-are associated with fertility in 10,250 women from 27 small-scale societies and found considerable variation in fertility. This variation did not align with group-level subsistence typologies. Societies labeled as "farmers" did not have higher fertility than others, while "foragers" did not have lower fertility. However, at the individual level, we found strong evidence that fertility was positively associated with farming and moderate evidence of a negative relationship between foraging and fertility. Markers of market integration were strongly negatively correlated with fertility. Despite strong cross-cultural evidence, these relationships were not consistent in all populations, highlighting the importance of the socioecological context, which likely influences the diverse mechanisms driving the relationship between fertility and subsistence.

  PublisherOA PDFDOI

• Medical mistrust, discrimination and healthcare experiences in a rural Namibian community

  Global Public Health · 2024-05-08 · 14 citations

  articleOpen access1st authorCorresponding

  = 86). Mixing semi-structured interview questions with the medical mistrust index (MMI), we aim to determine the relevance of the MMI in a non-industrialised population and compare index scores with reports of healthcare experiences. We find that medical mistrust is a salient concept in this community, mapping onto negative healthcare experiences and perceptions of discrimination. Reported healthcare experiences indicate that perceived incompetence, maltreatment and discrimination drive mistrust of medical personnel. However, reporting of recent healthcare experiences are generally positive. Our results indicate that the concept of medical mistrust can be usefully applied to communities in the Global South. These populations, like minority communities in the US, translate experiences of discrimination and marginalisation into medical mistrust. Understanding these processes can help address health disparities and aid in effective public health outreach in underserved populations.

  PublisherOA PDFDOI

• Quantifiable Cross-cultural Research on Medical Mistrust is Necessary for Effective and Equitable Vaccination in Low- and Middle-income Countries

  Journal of Epidemiology and Global Health · 2024-10-28 · 11 citations

  articleOpen access1st authorCorresponding

  Perceptions of healthcare personnel and institutions substantially impact healthcare behaviors. In the US, minority experiences with racist events like the Tuskegee study, alongside everyday experiences of marginalization and discrimination, drive medical mistrust in populations that are already burdened with health inequalities. However, the concept of medical mistrust is rarely applied outside of industrialized contexts. Histories of colonialism, underfunded healthcare institutions, and the enormous cultural and ethnolinguistic diversity present in low- and middle-income countries (LMICs) make medical mistrust a likely contributor to health behavior in these contexts. In the era of COVID-19 and emergent malaria vaccines, there is an urgent need to mitigate factors leading to medical mistrust, which impedes interest in novel vaccines. Doing so requires substantial investment in research that examines the causes of medical mistrust across diverse communities, develops methodological tools that can effectively measure medical mistrust across diverse cultural and ethno-linguistic contexts, and applies this data to policy and public health messaging. This commentary highlights the role of medical mistrust in vaccination and argues for its utility in addressing vaccine decision-making in LMICs.

  PublisherOA PDFDOI

Frequent coauthors

• Brooke A. Scelza

  University of California, Los Angeles

  32 shared

• Michael P. Muehlenbein

  Baylor University

  14 shared

• Brenna M. Henn

  University of California, Davis

  13 shared

• Elizabeth G. Atkinson

  Baylor College of Medicine

  11 shared

• Shyamalika Gopalan

  Stony Brook University

  10 shared

• Kathrine Starkweather

  University of Illinois Chicago

  7 shared

• Richard McElreath

  Max Planck Institute for Evolutionary Anthropology

  7 shared

• Jacob Sheehama

  University of Namibia

  7 shared

Labs

• Sean Prall LabPI

  Research focus on impacts of the fragmentation of perinatal care in the US, healthcare decisions in the Kunene region, Namibia, and vaccination decisions in Africa.

Education

• Postdoc, Anthropology

  University of California Los Angeles

  2019

• Phd, Anthropology

  Indiana University

  2014