Uploaded April 2026 | Updated September 2026, 2 weeks ago
Growing genomic evidence is revealing large strain diversity within populations of microbes encoded by multigene families and accessory genomes. One process of interest in explaining diversity patterns is competition for hosts via cross-immunity, which sets the stage for negative frequency-dependent selection (NFDS, an advantage of the rare and a disadvantage of the common) in transmission dynamics. Starting with literature results on the emergence of niches in mathematical models of competition for fixed and typically low trait spaces, I contrast the biology of pathogens whose vast strain diversity is defined in large combinatorial spaces of antigenic variation. I rely on the malaria parasite Plasmodium falciparum under high transmission as an example for this purpose, and present results of a stochastic computational (agent-based) model on the role of NFDS in strain diversity and its structure. With a simplified, more analytical tractable PDE model, I argue that the feedback of ecology and evolution which generates a large trait space matters to system resilience. I end with some potential implications and generalizations of these ideas to other eco-evolutionary systems.
For more information please visit: simonsfoundation.org/event/national-institute-for-theory-and-mathematics-in-biology-annual-meeting-2026
Growing genomic evidence is revealing large strain diversity within populations of microbes encoded by multigene families and accessory genomes. One process of interest in explaining diversity patterns is competition for hosts via cross-immunity, which sets the stage for negative frequency-dependent selection (NFDS, an advantage of the rare and a disadvantage of the common) in transmission dynamics. Starting with literature results on the emergence of niches in mathematical models of competition for fixed and typically low trait spaces, I contrast the biology of pathogens whose vast strain diversity is defined in large combinatorial spaces of antigenic variation. I rely on the malaria parasite Plasmodium falciparum under high transmission as an example for this purpose, and present results of a stochastic computational (agent-based) model on the role of NFDS in strain diversity and its structure. With a simplified, more analytical tractable PDE model, I argue that the feedback of ecology and evolution which generates a large trait space matters to system resilience. I end with some potential implications and generalizations of these ideas to other eco-evolutionary systems.
For more information please visit: simonsfoundation.org/event/national-institute-for-theory-and-mathematics-in-biology-annual-meeting-2026
