Club EvMed for October

Club EvMed for October

Club EvMed: How evolutionary behavioural sciences can help us understand behaviour in a pandemic

Thursday, October 14th at 11am EDT/17:00 CEST

Join us for a conversation with Ruth Mace, Professor of Evolutionary Anthropology at University College London, Emily Emmott, Lecturer in Anthropology at University College London, and Gul Deniz Salali, Lecturer in Evolutionary Anthropology at University College London. Prof. Mace will outline the main conclusions from taking a behavioural ecological approach to understanding the diversity of responses to behavioural responses to the COVID-19 pandemic. Dr. Emmott will outline her research on how the pandemic disrupted social networks, focusing on mothers of young babies and the risk of depression. Dr. Salali will present the findings from her ongoing project that tackles vaccine hesitancy (a delay in acceptance or refusal of vaccines) using predictions from cultural evolution theory.

Attendees are encouraged to read Arnot et al. 2020, “How evolutionary behavioural sciences can help us understand behaviour in a pandemic,” Myers and Emmott 2021, “Communication across maternal social networks during England’s first national lockdown and its association with postnatal depressive symptoms,” and Salali and Uysal 2021, “Effective incentives for increasing COVID-19 vaccine uptake.” Sign up here for the meeting link:https://duke.zoom.us/meeting/register/tJYpduqurj8pHtX6sw09hbk0CAWWIoZ6x7b0.

Club EvMed: Evolutionary demography sheds light on the allelic spectrum of late-onset diseases

Thursday, October 21st at 1pm EDT/19:00 CEST

Join us for a conversation with Samuel Pavard, Associate Professor at the National Museum of Natural History in Paris, France, and Christophe Coste, Researcher at the Norwegian University of Science and Technology. Geneticists have long considered alleles involved in post-menopause mortality to be neutral as no reproduction occurs anymore. Population genetics models have predicted that genetic drift rather than purifying selection was shaping the allelic spectrum of late-onset diseases, leading to a few common variants explaining most of the diseases’ prevalences. However, recent association studies show that most susceptibility alleles to late onset diseases have low frequencies: a characteristic of alleles under negative selection. We show that susceptibility alleles to late onset diseases are under purifying selection for most known age-at-onset distributions of late-onset genetic diseases. We conclude that neutrality is probably the exception among alleles that have a deleterious effect in old age and that accounting for sociocultural factors is required to understand the full extent of the force of selection shaping senescence in humans.

Attendees are encouraged to read Pavard and Coste 2021, “Evolutionary demographic models reveal the strength of purifying selection on susceptibility alleles to late-onset diseases.” Sign up here for the meeting link: https://duke.zoom.us/meeting/register/tJEsdO-qrj8rHN2ZFNrYpaqLoAwWIJebhNPX.

EMPH Emphasis: Williams Prize, 48 Clinical Briefs, and higher impact factor

EMPH Emphasis: Williams Prize, 48 Clinical Briefs, and higher impact factor

Evolution Medicine and Public Health has now published 48 Clinical Briefs, now all conveniently listed together for easy access. Each one provides a single page about how an evolutionary view illuminates a clinical condition.

Renee Hagen

The best article in the journal each year receives the $5000 Williams Prize. This year’s prize is for an article by Renee Hagen and Brooke Scelza “Adoption of outgroup norms provides evidence for social transmission in perinatal care practices among rural Namibian women” 

Submit your article now!

EMPH is an open access journal published by Oxford University Press that is edited by Charles Nunn. Under his editorship the journal impact factor has just increased to 5.425.

Club EvMed June 29

Club EvMed: Of Mice and Elephants: Trade-Offs of Tumor Suppressor Duplication and Body Size Evolution in Afrotheria

Tuesday, June 29th at 12pm EDT/18:00 CEST

Join us for a conversation with Juan Manuel Vazquez, Postdoctoral Scholar at the University of California-Berkeley. Peto’s Paradox describes the observation that while cancer risk is correlated with body size and lifespan within species, no such correlation holds between species. This indicates that large, long-lived species have evolved enhanced cancer protection mechanisms, and that these mechanisms may be used to treat and even prevent human cancers, and extend the human healthspan. The recent expansion of body size in elephants relative to other members of their resident clade of Afrotheria led us to explore how both body size and lifespan evolved in this group. Unexpectedly, we found that tumor suppressor duplication was pervasive in Afrotherian genomes, rather than restricted to Proboscideans. Proboscideans, however, have duplicates in unique pathways that may underlie some aspects of their remarkable anti-cancer cell biology. These data suggest that duplication of tumor suppressor genes facilitated the evolution of increased body size by compensating for decreasing intrinsic cancer risk. In our talk, we will begin with a summary of these findings, then move on to a discussion of the implications of tumor suppressor duplicates in the development and fitness of various animals, and of a new paradox: how can an organism’s body size expand given enhanced genetic shackles on growth?

Attendees are encouraged to read Vazquez and Lynch 2021, “Pervasive duplication of tumor suppressors in Afrotherians during the evolution of large bodies and reduced cancer risk” and García-Cao et al. 2002, “‘Super p53’ mice exhibit enhanced DNA damage response, are tumor resistant and age normally.” Sign up here for the meeting link: https://duke.zoom.us/meeting/register/tJUpfu2rrjgvHNUJVdX4ddvbEaa9Vv1di0wR.

The Price of Optimism

The Price of Optimism

Gassen, J., Nowak, T. J., Henderson, A. D., Weaver, S. P., Baker, E. J., & Muehlenbein, M. P. (2021). Unrealistic Optimism and Risk for COVID-19 Disease. Frontiers in Psychology, 12, 647461. https://doi.org/10.3389/fpsyg.2021.647461

Risk perception and consequently engagement in behaviors to avoid illness often do not match actual risk of infection, morbidity, and mortality. Unrealistic optimism occurs when individuals falsely believe that their personal outcomes will be more favorable than others’ in the same risk category. Natural selection could favor overconfidence if its benefits, such as psychological resilience, outweigh its costs. However, just because optimism biases may have offered fitness advantages in our evolutionary past does not mean that they are always optimal. The current project examined relationships among personal risk for severe COVID-19, risk perceptions, and preventative behaviors. We predicted that those with higher risk of severe COVID-19 would exhibit unrealistic optimism and behave in ways inconsistent with their elevated risk of morbidity and mortality. See link for full article

ClubEvMed Upcoming Events

ClubEvMed Upcoming Events

Sign up now for April and May ClubEvMed events!

(And submit your ISEMPH2021 abstract by Friday!)

Postdoc Spotlight

Thursday, April 29th at 12pm EDT/18:00 CEST

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 Kyle CardLiz Lange, and Federica Pierini (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.

“The effect of population size, mutation rate, and genetic background on the evolution of antibiotic resistance” by Kyle Card, Cleveland Clinic
The evolution of antibiotic resistance is a serious and growing problem. The ability to predict a pathogen’s capacity to evolve resistance is therefore a critical public-health goal. In previous work, we found that differences between genetic backgrounds can sometimes lead to unpredictable responses in phenotypic resistance and influence its genetic basis by channeling evolution down particular mutational paths. However, it is still not clear how background interacts with other factors, including population size and mutation rate to influence resistance evolution. To address this issue, we are combining theory with an experimental examination of a time-series of E. coli strains isolated from a population that evolved increases in both population size and mutation rate during a long-term evolution experiment (LTEE).

“Female-female social bonds mediate the relationship between early life adversity and lifespan in wild baboons, but female-male social bonds do not” by Liz Lange, Duke University
Adversities experienced during early life and adult social environments can have profound effects on human health and survival. However, it is unclear if experiences during early life and adulthood exhibit independent effects on survival, or instead if these processes are linked such that adverse early experiences are strongly coupled with dysfunction in adult social relationships, which in turn are strongly coupled with decreased lifespan. In this study we used longitudinal data on 199 wild adult female baboons from the Amboseli ecosystem in Kenya to determine the links between early life adversity, adult social bonds, and adult survival outcomes. We find that early adversity and social isolation from both males and females reduce survival, but only female-female social bonds link early life adversity to reduced survival. Our results suggest that the timing of effects (e.g., the effect of early adversity on social bonds and social bonds on survival) are crucial to determining the links between these processes and should be considered in human studies of adverse childhood experiences.

“Exploring immunogenetic diversity in historical human populations” by Federica Pierini, Max Planck Institute for the Science of Human History
The highly polymorphic genes of the human leukocyte antigen (HLA) system play a key role in adaptive immunity. Pathogen-mediated selection is proposed to be one of the major factors affecting the genetic variability at those genes, but our knowledge is so far based on information acquired from the study of present-day human populations. The investigation of ancient HLA genes in historical populations could shed further light on mechanisms of pathogen-mediated selection in humans. I will first show our novel aDNA-optimized pipeline for low-coverage and low-quality shotgun sequence data and follow with two examples of its applicability. The approach has been successfully applied to a dataset of Late Neolithic samples from a collective burial in Niedertiefenbach (Germany), revealing a distinct and characteristic HLA gene pool compared to modern day German individuals, and to a dataset of medieval European samples, associating HLA variability with susceptibility to leprosy.

The COVID-19 Pandemic and Human Nature: An Interdisciplinary Conversation

Monday, May 10th at 12pm EDT

This Club EvMed will feature a dynamic roundtable conversation with several authors of the recently published PNAS paper, “The pandemic exposes human nature: 10 evolutionary insights.” Moderated by Dan Blumstein (Professor of Ecology and Evolutionary Biology at UCLA), the panel’s discussants will include Athena Aktipis (Assistant Professor of Psychology at Arizona State University), Martie Haselton (Professor of Psychology at UCLA), and Joe Alcock (Professor of Emergency Medicine at the University of New Mexico). They will provide a range of evolutionary insights and hypotheses related to the impact of COVID-19 on human health and social systems. Sign up here for the meeting link.

Divergent evolutionary roots for posttraumatic stress disorder symptoms

Monday, May 17th at 12pm EDT

Join us for a conversation with Sarah Mathew, Associate Professor in the School of Human Evolution and Social Change at Arizona State University, and Matthew Zefferman, Assistant Professor in the Department of Defense Analysis at the Naval Postgraduate School. Military personnel in industrialized societies often develop Post-traumatic Stress Disorder (PTSD) during combat. It is unclear whether combat-related PTSD is a universal evolutionary response to danger, or a culture-specific syndrome of industrialized societies. We interviewed 218 Turkana pastoralist warriors in Kenya, who engage in lethal cattle raids, about their combat experiences and PTSD symptoms. Compared to American combat veterans, Turkana suffer PTSD symptoms at high rates, but have lower prevalence of depression-like PTSD symptoms. Symptoms that facilitate responding to danger were better predicted by combat exposure, whereas depressive symptoms were better predicted by exposure to combat-related moral violations. The findings suggest that some PTSD symptoms stem from a universal response to danger, while depressive PTSD symptoms may be caused by culturally-specific moral norm violations.

Attendees are encouraged to read Zefferman and Mathew 2021, “Combat stress in a small-scale society suggests divergent evolutionary roots for posttraumatic stress disorder symptoms” and Zefferman and Mathew 2020, “An evolutionary theory of moral injury with insight from Turkana warriors.” Sign up here for the meeting link.