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To address claims of human exceptionalism, we determine where humans fit within the greater mammalian distribution of reproductive inequality. We show that humans exhibit lower reproductive skew (i.e., inequality in the number of surviving offspring) among males and smaller sex differences in reproductive skew than most other mammals, while nevertheless falling within the mammalian range. Additionally, female reproductive skew is higher in polygynous human populations than in polygynous nonhumans mammals on average. This patterning of skew can be attributed in part to the prevalence of monogamy in humans compared to the predominance of polygyny in nonhuman mammals, to the limited degree of polygyny in the human societies that practice it, and to the importance of unequally held rival resources to women's fitness. The muted reproductive inequality observed in humans appears to be linked to several unusual characteristics of our species-including high levels of cooperation among males, high dependence on unequally held rival resources, complementarities between maternal and paternal investment, as well as social and legal institutions that enforce monogamous norms.

Small group learning activities have been shown to improve student academic performance and educational outcomes. Yet, we have an imperfect understanding of the mechanisms by which this occurs. Group learning may mediate student stress by placing learning in a context where students have both social support and greater control over their learning. We hypothesize that one of the methods by which small group activities improve learning is by mitigating student stress. To test this, we collected physiological measures of stress and self-reported perceived stress from 26 students in two undergraduate classes. Salivary cortisol and testosterone were measured within students across five contexts: a) pre-instructional baseline, b) following a traditional lecture, c) after participating in a structured small group learning activity, d) following completion of multiple choice, and e) essay sections of an exam. Results indicate students have lower salivary cortisol after small group learning activities, as compared to traditional lectures. Further, there is no evidence of a relationship between physiological measures of stress and self-reported perceived stress levels. We discuss how structured small group activities may be beneficial for reducing stress and improving student-learning outcomes.

Objective: Food insecurity is a significant and growing concern undermining the wellbeing of 30% of the global population. Food in/security is a complex construct consisting of four dimensions: availability, access, utilization, and stability, making it challenging to measure. We provide a toolkit human biologists/ecologists can use to advance research on this topic. Methods: We review the strengths and limitations of common tools used to measure food access and utilization, the two dimensions most proximate to people's lived experience, and emphasize tools that provide data needed to best link food security with human biological outcomes. We also discuss methods that provide contextual data human biologists/ecologists will find useful for study design, ensuring instrument validity, and improving data quality. Results: Food access is principally measured using experience‐based instruments that emphasize economic access. Social access, such as food sharing, is under‐studied and we recommend using social network analysis to explore this dimension. In terms of utilization, emphasis has been on food choice measured as dietary diversity. Food preparation and intrahousehold distribution, also part of the utilization dimension, are less studied and standardized instruments for measuring both are lacking. The embodiment of food insecurity has focused on child growth, although a growing literature addresses adult mental wellbeing and chronic and infectious disease risk. Conclusions: We see the potential to expand outcomes to include reproductive and immune function, physical activity, and the gut microbiome. Human biologists/ecologists are well‐positioned to advance understanding of the human health impacts of food insecurity and provide data to support intervention efforts. [ABSTRACT FROM AUTHOR]