Natural Selection is stressful – future generations propagate from the individuals who fight off immunological, energetic, and social threats long enough to ensure that their offspring reproduce. For many of the threats to our fitness, we have a direct physiological sense to alert us that something is wrong. When an individual needs more food, they feel hungry. When they are cut, they feel pain. However, we do not have specific, physiological conduits for social interactions to act upon – we are not directly, physically harmed when one of our family members passes away. Instead, we experience a range of psychological symptoms, including anger, sadness, and anhedonia. Losing social relationships rarely impacts our survival immediately, but the nature of our development and reproductive systems necessitate strong and continuous social support.

Human survival and reproductive fitness depend upon an extended, intricate web of social relationships – we gain most, if not all, of our resources and capital through our connections to others. In most ecological contexts, humans produce fewer resources than they consume until the end of adolescence (Kaplan, 1996; Kramer, 2005) and many individuals in industrialized settings do not surpass this threshold until young adulthood. However, even when an individual begins to provide more to their social networks than they consume, they still rely upon others for survival (Kaplan, 1996). Humans require social support to acquire ecological knowledge, assistance from others with specialized skills (e.g. midwifery, hunting, etc.), and access to shared energetic resources (e.g. farming, hunting, grocery stores, etc.). Strained, abusive, and lost relationships represent threats to our resources, and, by extension, our reproductive fitness.

In my work, I am interested in how psychosocial stress allows us to mobilize our biology in response to these changes in our environment to form coherent fitness-improving (or at least fitness-relevant) strategies. Researchers have found that increased exposure to psychosocial stressors is connected to long-term changes in immune markers, sex steroids, glucocorticoids, brain morphology, stature, offspring birth weight, and many other biomarkers (Kuzawa and Sweet, 2009; Lupien et al., 2009; Danese and McEwen, 2012; Hostinar and Gunnar, 2013). Among these myriad biomarkers, epigenetic modifications and telomere biology have received much of the recent limelight because of their long-lasting impacts on health. Epigenetic modifications allow our cells to adjust genetic expression based on environmental input and telomeres are strongly connected to cellular aging.

Specifically, I hope to elucidate how social and physical environments (e.g. cultural understandings of distress and pathogen exposure, respectively) moderate how psychosocial stressors are related to these changes in biology. Wellbeing does not have a ‘blood test’ that can be applied universally, and its meaning varies considerably based on local contexts – both on what is understood to be stressful and what non-social pressures are acting upon an individual’s biology. I hypothesize that differences in both domains will drive what stimuli and circumstances are stressful and how individuals respond biologically. Ultimately, I expect that the moderation effects of these aspects of environments will be relevant to both modern and evolutionary populations, and will be important in fully understanding the evolution of human biology.

At UW, I am being advised by Dr. Dan Eisenberg and am currently working to finish my Master’s paper on this topic and design my dissertation project.

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