Marisa Azad

University of Ottawa, Canada

Brendan Bohannan

University of Oregon, United States

Talk title: The social microbiome and public health

Abstract

It has long been known that pathogenic microbes can be transmitted through social interactions among host individuals. Recent studies of insects, mammals, birds, non-human primates, and humans have revealed that non-pathogenic (i.e. beneficial or commensal) microbes can also be socially transmitted, and that socially interacting hosts have more similar microbiomes. These observations have led to the concept of the social microbiome—the community of microbes exchanged among host individuals that share a social network. Social transmission has important consequences for evolution, providing for example a mechanism for microbiome heritability across host generations. The social transmission of non-pathogenic microbes also has important implications for medicine and public health. Recent studies suggest that socially transmitted non-pathogenic microbes share unique traits, and that socially assembled microbiomes can make unique, positive contributions to host health, implying that health may be transmissible in ways analogous to the transmission of disease. Given this possibility, strategies for reducing the spread of infectious disease (such as social distancing and quarantine) may have unintended negative impacts on the transmission of beneficial microbes, which could lead to negative consequences for health. Public health strategies that reduce the spread of disease while minimally impacting the transmission of health are thus needed. Designing such strategies will require a much deeper understanding of the social microbiome, especially the dispersal biology of pathogenic vs non-pathogenic microbes.

About the speaker

Brendan is the Alec and Kay Keith Professor at the University of Oregon and the director of the university’s Institute of Ecology and Evolution. He is a contributor to the Proceedings of the National Academy of Sciences. In 2019, he was awarded a $7.6 million grant from the U.S. National Institutes of Health to investigate the potential health benefits of bacteria. His research focuses on understanding the causes and consequences of microbial biodiversity. With his research group, he examines the fundamental drivers of biodiversity, the effects of environmental change on microbial communities, and how microbial diversity changes in human-dominated environments—including those within the human body and other host organisms.

Trevor Graham

Institute of Cancer Research, United Kingdom

About the speaker

Trevor joined the Institute of Cancer Research as Director of the Centre for Evolution and Cancer in 2022 and is a group leader of the Genomics and Evolutionary Dynamics laboratory. For the previous 8.5 years Trevor led the Evolution and Cancer laboratory at the Cancer Research UK Barts Cancer Institute within Queen Mary University of London. Trevor’s laboratory was the first mathematical theory-led laboratory in the Institute. He co-led the development of computational biology as core research theme at Barts, culminating in the establishment of the Centre for Genomics and Computational Biology in 2019, where Trevor was deputy lead. Trevor’s research is focused on understanding the evolutionary dynamics of cancer development and translating this knowledge to improve clinical management of disease. His laboratory combines expertise in evolutionary theory, mathematical modelling and bioinformatics, together with cutting-edge wet-lab analyses foremost in genomics, single cell sequencing and molecular pathology.

Johannes Krause

Max Planck Institute for Evolutionary Anthropology, Germany

About the speaker

Johannes is the Managing Director of the Max Planck Institute for Evolutionary Anthropology and a leading expert in ancient DNA research. He focuses on the analysis of ancient DNA to investigate such topics as pathogens from historic and prehistoric epidemics, human genetic history, and human evolution. He has contributed to deciphering Neanderthal genetics and the shared genetic heritage of Neanderthals and modern humans. In 2010, he discovered the first genetic evidence of the Denisovans, an extinct hominin found in the Altai Mountains in Siberia. His recent work includes revealing the genetic heritage of ancient Egyptians, reconstructing the oldest modern human genome, studying late Pleistocene genomes from Africa, Central Asia and Europe, uncovering the source of the epidemic plague bacteria that periodically caused historic and prehistoric epidemics in Eurasia, studying the evolution and genetic history of pathogens such as Mycobacterium leprae, M. tuberculosis, Treponema pallidum, Hepatitis B virus, Salmonella enterica, Helicobacter pylori and the Herpes virus, as well as clarifying the complex history of Western Eurasia’s prehistoric mass migrations. He has authored more than 250 publications, mainly in peer-reviewed journals, including Nature, Science, Cell, Nature Reviews Genetics, etc. He has given more than 400 invited presentations and his research has been featured in numerous television, radio, print and online media sources, including The New York Times, Washington Post, BBC, NPR, Discovery Channel, National Geographic, Zweites Deutsches Fernsehen, 3Sat, ARTE, Der Spiegel, FAS, FAZ, Die Zeit, Die Welt, Süddeutsche Zeitung, Science, Nature, and considerably more. He has also authored two international bestsellers focusing on human history: A Short History of Humanity: How Migration Made Us Who We Are and Hubris: The Journey of Humankind.

Lynnette Leidy Sievert

University of Massachusetts Amherst, United States

Talk title: Beyond the end of fertility:  evolutionary perspectives on menopause, post-reproductive aging, and women’s health

Abstract

For comparative biologists, menopause is the end of female fertility observed across mammalian taxa. For human biologists, female menopause is a universal life history event within the genus Homo. For perimenopausal women, evolution may seem to be irrelevant as complaints at midlife range from hot flashes to itchy ears. Why does menopause occur, and why is it accompanied by hot flashes, vaginal dryness, risk of osteoporosis, and other complaints and concerns? Post-reproductive life occurs when female longevity extends beyond the supply of gametes. Our own longevity lengthened more than one million years ago, alongside an increase in cranial capacity, tool use, the benefits of fire, and protection from predators.  Among all female mammals, the depletion of gametes across the lifespan is a highly conserved trait. The gradual loss of ovarian follicles and concomitant decline in levels of estradiol contribute to symptoms attributed to menopause, although naturally occurring hot flashes appear limited to humans. From an evolutionary perspective, the lengthened somatic lifespan is a mismatch. Alternatively, we can identify the importance of estrogen early in life for thermoregulation, vaginal health, and bone strength to explain the deleterious effects of estrogen withdrawal at menopause and beyond.

About the speaker

Lynnette has studied variation in age at menopause and symptoms at midlife for more than 30 years.  In collaboration with local researchers, she carried out studies of menopause in western Massachusetts; Hilo, Hawaii; the Selška Valley, Slovenia; Asunción and Mbaracayu, Paraguay; Puebla and Campeche, Mexico; Sylhet, Bangladesh; and London, UK, as well as pilot studies in Odisha, India, and Ulaanbaatar, Mongolia.  Lynnette also studies and writes about the evolution of menopause and post-reproductive life.  Of late, she has been disentangling the experience of hot flashes from the heat and humidity of Campeche, Mexico, and planning to study hot flashes in the winter cold of Mongolia.  Her current study is on hot flashes in relation to estimates of brown adipose tissue.  Lynnette is an elected Fellow of the AAAS, served on the Board of Trustees of the North American Menopause Society, and was the Editor-in-Chief of the American Journal of Human Biology, the journal of the Human Biology Association.