Biology subjects

Emery Thompson, M.

Publications and source records attributed to Emery Thompson, M..

4 recordsLinked to original sources

bioRxiv2026

Sex-specific effects of social bonds on glucocorticoids in wild chimpanzees

Across social species, strong social bonds are linked to health benefits, including reduced disease risk and increased survival. Chronic glucocorticoid exposure, frequently associated with negative health outcomes, may mediate this relationship, as bonds may reduce stressor exposure or buffer physiological responses. Among primates, these relationships have mostly been studied in female-bonded species, where kinship shapes cooperation and access to resources. Whether bonds confer simsilar benefits in species with different social structures - especially bonds between non-kin - remains unclear. We tested whether strong affiliative bonds were associated with glucocorticoid production in wild adult chimpanzees using 22 years of behavioural and urinary cortisol data. Bonds were quantified for same-sex adult dyads using an index of party association, proximity, and grooming. Bond strength was measured by averaging each individuals top three bonds per year. Stronger bonds predicted lower cortisol in females but higher cortisol in males, a pattern that persisted after accounting for dominance rank, aggression, and contextual stressors. In this male-bonded species, stronger male bonds predicted higher physiological costs, while stronger female bonds, though weaker, appeared to attenuate stress. Our results challenge the assumption that social bonds are universally health-promoting, and suggest their physiological consequences vary with sex and social organization.

evolutionary biology↗

bioRxiv2021

Helminth infection is associated with dampened cytokine responses to viral and bacterial stimulations in Tsimane hunter-horticulturalists.

BackgroundSoil-transmitted helminth (STH) infections can catalyze immunological changes that affect the response to subsequent infections, particularly those that elicit strong inflammatory responses. As globalization heightens the risk that remote communities with high STH prevalence will encounter novel pathogens, understanding how STHs shape immune responses to these downstream infections becomes increasingly crucial. MethodologyWe worked with Tsimane forager-horticulturalists in the Bolivian Amazon, where STHs are prevalent. We tested whether STHs and eosinophil levels--most likely indicative of infection in this population--are associated with dampened immune responses to in vitro stimulation with H1N1 and lipopolysaccharide (LPS) antigens. Whole blood samples (n = 179) were treated with H1N1 vaccine and LPS and assayed for 13 cytokines (interferon gamma [INF-{gamma}], interleukin [IL]-1{beta}, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12p70, IL-13, Granulocyte-macrophage colony-stimulating factor [GM-CSF], and Tumor necrosis factor-alpha [TNF-]). We evaluated how STHs and eosinophil levels affected cytokine responses and T helper (Th) 1 and Th2-cytokine suite responses to stimulation. ResultsInfection with Ascaris lumbricoides was significantly (p [≤] 0.05) associated with lower response of some cytokines to H1N1 and LPS in women. Eosinophils were significantly negatively associated with some cytokine responses to H1N1 and LPS, with the strongest effects in women, and associated with a reduced Th1- and Th2-cytokine response to H1N1 and LPS in women and men. Conclusions and implicationsWe find that STHs were associated with dampened cytokine responses to certain viral and bacterial antigens, and suggest that this mitigation of host-induced damage may reduce the incidence of cytokine storms in populations with high STH prevalence.

immunology↗

bioRxiv2021

Age-related change in adult chimpanzee social network integration

BackgroundSocial isolation is a key risk factor for the onset and progression of age-related disease and mortality in humans, yet older people commonly have narrowing social networks. Few models explain why human networks shrink with age, despite the risk that small networks and isolation pose. We evaluate models grounded in a life history perspective by studying social aging in wild chimpanzees, which are long-lived and show physical decline with age. MethodologyWe applied social network analysis to examine age-related changes in social integration in a 7+ year mixed-longitudinal dataset comprised of 38 wild adult chimpanzees (22 F, 16 M) in the Kanyawara community in the Kibale National Park, Uganda. Metrics of social integration included social attractivity and overt effort (directed degree and strength), gregariousness (undirected strength), social roles (betweenness and local transitivity), and embeddedness (eigenvector centrality) in grooming and spatial association networks. ResultsMales reduced overt social effort yet increased in attractivity, roles in cliques, and embeddedness. Females were overall less integrated than males, and their decreased integration with age suggested social avoidance. Effects of age were largely independent of rank. Both sexes maintained highly repeatable inter-individual differences in several aspects of integration, particularly among mixed-sex partners. Conclusions and implicationsAs in humans, chimpanzees experience age-related declines in social effort. However, important facets of integration aged more similarly to humans in non-industrialized vs. industrialized societies, suggesting an evolutionary social mismatch between conserved declines in effort and dynamics of industrialized society. Lastly, individual and sex differences have the potential to be important mediators of successful social aging in chimpanzees, as in humans.

animal behavior and cognition↗

bioRxiv2019

Parallel signatures of mammalian domestication and human industrialization in the gut microbiota

Domestication may have had convergent effects on the microbiota of domesticates and humans through analogous ecological shifts. Comparing the gut microbiota of domestic and related wild mammals plus humans and chimpanzees, we found consistent shifts in composition in domestic animals and in humans from industrialized but not traditional societies. Reciprocal diet switches in mice and canids demonstrated that diet played a dominant role in shaping the domestic gut microbiota, with stronger responses in the member of the wild-domestic pair with higher dietary and microbial diversity. Laboratory mice recovered wild-like microbial diversity and responsiveness with experimental colonization. We conclude that domestication and industrialization have similarly impacted the gut microbiota, emphasizing the utility of domestic animal models and diets for understanding host-microbial interactions in rapidly changing environments.

microbiology↗