American Journal of Human Biology最新文献

Neandertals occupied western Eurasia for over 100 000 years, repeatedly enduring climates that ranged from seasonally cold to glacial. This paper reexamines the question of Neandertal cold adaptation using updated fossil, physiological, and archaeological evidence. While some populations lived outside glacial extremes, all faced periodic cold stress, and their survival depended on a diverse set of strategies. Technological buffers, including fire use, hide processing tools, and possible clothing and footwear, likely played a primary role in reducing cold exposure. Anatomically, Neandertals exhibit high body mass, broad trunks, and abbreviated limbs, consistent with thermoregulatory principles. The Neandertal nasal region, long considered paradoxical, now appears well suited to cold-dry air-conditioning; computational fluid dynamics and new endoscopic data support a functionally integrated nasal cavity with substantial internal surface area. Physiological adaptations remain inferential but plausible, including elevated basal metabolism, energy-dense diets, and potential use of brown adipose tissue. These factors likely contributed to high total energy expenditures, enabling thermoregulation in demanding environments. Rather than a single trait or “signature” adaptation, Neandertals present an integrated response to cold stress shaped by geography, development, culture, and genetics. This holistic view reframes Neandertal biology as deeply thermally engaged and sets the stage for targeted tests of function and mechanism in future research.

Human biologists seek to understand how cultural, environmental, and biological forces shape observed patterns of human variation. Yet contemporary insights and approaches to observational causal inference remain underutilized in the field. We outline a structured but flexible roadmap for causal inference in human biology that begins with theory development, defines causal questions and estimands, employs directed acyclic graphs (DAGs) to clarify assumptions, and evaluates key identification criteria prior to statistical analysis. We position this framework within a spectrum of causal inference traditions, spanning from interventionist approaches rooted in well-defined, manipulable exposures to realized approaches that engage historically situated and ecologically embedded phenomena. Rather than offering a prescriptive checklist, we frame this toolkit as an opening: a step toward anthropological causal inference that integrates transparency, theoretical and methodological coherence, and the epistemological commitments of the biocultural synthesis in human biology and anthropology.

Arab adolescents are both racialized and invisible minorities in Canada and the United States (US), following the war on terror, incomplete ethnic categorization, Islamophobia, and anti-Arab racism. We conducted a scoping review of physical and psychological health in Arab adolescent populations living in the US and Canada. Inclusion criteria encompassed adolescents and emerging adults aged 10–24 who identified as Arab or having Arab identity and Southwest Asia and North Africa (SWANA) origins. Included scholarly literature reported at least one physical or psychological health outcome and was published in English or Arabic up until 2025. We identified over 200 relevant studies using PubMed, Web of Science, ResearchRabbit.ai, Google Scholar, and Undermind AI. We reviewed 50 total studies that met our inclusion criteria, highlighting the paucity of research on health and biopsychosocial variation among Arab adolescents in North America over a 30-year period. Despite heterogeneity in the health outcomes reported across studies, many focused on acculturative stress, ethnic identity formation, mental health, and discrimination. Few studies examined physical health and sexual and reproductive health; none examined pubertal, immunological, or linear growth outcomes. We discuss how biocultural and human biological research approaches can contribute to advancing a needed and more holistic understanding of health variation among Arab adolescent populations.