Club EvMed: Postdoc Spotlight

Wednesday, November 4th at 1pm EST

Join us for a special Club EvMed where we’ll be highlighting some of the exciting work done by postdoctoral researchers in the field of evolutionary medicine. We will hear 12-minute research talks from Caroline Amoroso, Amrita Bhattacharya, and Angela Garcia (see abstracts below). There will be a brief Q&A period at the end of each talk, plus breakout rooms after all 3 talks to allow for more in depth conversations with the speakers. Sign up here for the meeting link: https://duke.zoom.us/meeting/register/tJIkd-6sqz4oH9La2lRh3NJ-cGgDzW6m3Dbj.

Evolution of host behavioral resistance to pathogens” by Caroline Amoroso, University of Virginia

Evolutionary theory about host resistance to pathogens has typically focused on physiological mechanisms of resistance, yet strategies that hosts use to prevent pathogen infection can also be behavioral. Using a framework established in previous work on physiological resistance, I develop a model of behavioral resistance to a socially transmitted disease and use it to explore evolutionary dynamics under different assumptions about the avoidance strategy and nature of costs. I discuss the parallels between behavioral and physiological forms of resistance, and the limitations of physiological resistance theory for explaining the evolution and disease dynamics of behavioral resistance.

Exceptions to the rule: Why does resistance evolution not undermine antibiotic therapy in all bacterial infections?” by Amrita Bhattacharya, Pennsylvania State University

Antibiotic resistance is among the greatest public health crises of the 21st century, but the phenomenon of resistance evolution is not surprising. Antibiotics impose strong selective pressure on bacteria to survive, reproduce, and transmit in their presence leading to the evolution of antibiotic resistance. Yet not all human bacterial infections are affected by resistance evolution. Why? Here we attempt to understand (a) in which cases resistance evolution has not undermined treatment-efficacy, and (b) which factors, if any, can explain these patterns of resistance evolution. We are surveying the scientific literature over the last five years to determine variation in the prevalence of resistance across 57 species of human bacterial pathogens and the subset of 79 antibiotics from 15 different drug classes used to treat them. We examine the variation in resistance across these ‘pathogen x antibiotic’ combinations, and determine how factors such as mechanism of drug action, pathogen classification, mode of transmission, human-to-human transmission, presence of pathogen in the human microbiome, natural competence, and aerobic/anaerobic growth correlate with the observed patterns of resistance.

Evidence for height and immune function trade-offs among pre-adolescents in a high pathogen population” by Angela Garcia, Arizona State University

In an energy-limited environment, investment in one trait should trade-off with investment in other traits. In high pathogen ecologies, biasing energy allocation towards immunity over growth would be predicted, given strong selective pressures against early-life mortality. Here, I examine trade-offs between adaptive immune and height among young children in the Bolivian Amazon. Tracking tradeoffs between growth and immune function is enormously complex, particularly due to the changing relationships between distribution of body fat and mass relative to height, and shifts in allocation between life history traits, that occur during this period of active growth and development. However, the consistent negative associations across the numerous markers of adaptive immune function and height-for-age documented in this research prompt consideration of whether there may be a threshold of investment into adaptive immune function required for survival in high pathogen environments. 

Club EvMed: The Nature of Fear

Thursday, November 12th at 12pm ET

Join us for a conversation with Daniel Blumstein, Professor of Ecology and Evolutionary Biology at the University of California Los Angeles. Fear, honed by millions of years of natural selection, kept our ancestors alive. Whether by slithering away, curling up in a ball, or standing still in the presence of a predator, humans and other animals have evolved complex behaviors in order to survive the hazards the world presents. But, despite our evolutionary endurance, we still have much to learn about how to manage our response to danger. Delving into the evolutionary origins and ecological contexts of fear across species, Blumstein’s book The Nature of Fear considers what we can learn from our fellow animals—from successes and failures. By observing how animals leverage alarm to their advantage, we can develop new strategies for facing risks without panic. Sign up here for the meeting link: https://duke.zoom.us/meeting/register/tJIqfu-sqD0qHdGyd1wHuIx_HzZCL-LIYCBF.

Club EvMed: Social immunity: cooperative disease defense in social insect colonies

Tuesday, November 17th at 11am EST

Join us for a presentation by Sylvia Cremer, Professor at the Institute of Science and Technology Austria, followed by a conversation with Nathalie Stroeymeyt, Senior Lecturer at the University of Bristol, and Chris Pull, Lecturer at the University of Oxford. Infectious disease can easily spread when hosts live in social groups. On the other hand, the members of social groups can fight disease together. The social insects — the social bees and wasps, ants and termites — have evolved a special form of social group living: the colony. Dr. Cremer will present how ant colonies are protected against disease by the combination of the individual immune defenses of all colony members and their collective hygiene behaviors performed jointly or towards one another. This social immunity is achieved by cooperative actions to reduce pathogen load of the colony and to prevent transmission along the social interaction networks of colony members. Attendees are encouraged to read Cremer 2019, “Social immunity in insects,” Stroeymeyt et al. 2018, “Social network plasticity decreases disease transmission in a eusocial insect,” and Konrad et al. 2012 “Social transfer of pathogenic fungus promotes active immunization in ant colonies.” Sign up here for the meeting link: https://duke.zoom.us/meeting/register/tJIqcOCrrD0rGtQrQwhh1ZDBx0gCsh3jVRNE.