Microbial communities can display a wide range of dynamics, including alternative stable states, oscillations, and chaotic fluctuations. Although tremendous progress has been made in characterizing communities of microorganisms, the lack of experimentally tractable model systems has made it difficult to discern the principles governing microbial community stability and function. In this talk I will describe progress over the last decade in understanding how interactions within a community can lead to these emergent dynamical behaviors. Positive feedback loops drive alternative stable states, whether governed by intra-species cooperative growth, mutual antagonism within a pair of species, or distributed inhibition throughout a multi-species community. In this last case, a multi-species community can display alternative stable states even when none of the constituent pairs of species display bistability. As the number of species in the community grows, the complex network of interactions generically leads to the loss of stability and the emergence of persistent fluctuations in species abundance. These results provide insight into mechanisms that drive potentially generic behaviors in diverse ecological communities.

See for more information on Jeff Gore and Martina Dalbello.

Registration at https://univienna.zoom.us/meeting/register/fISRS15HQAi3m39QN9RZWQ