Watch recorded past seminars on our YouTube channel:

Stefano Allesina (University of Chicago): A metapopulation model in which patches have memory

Levins' metapopulation model has been extended in numerous ways. Here we analyze a model in which species have distinct colonization rates that depend on which species previously occupied the patch. We connect this model to the Janzen-Connell hypothesis and show some surprising behavior for a simplified version of the model. Zoom link: eventbrite link […]

Nadav Shnerb (Bar-Ilan University): Quantifying coexistence

Abstract. Modern coexistence theory employs mutual invasibility as a coexistence criterion and mean growth rate when rare as an invasibility criterion. When implemented as quantitative metrics, both criteria have shortcomings: persistence time may decline when the chance of invasion grows, and invasibility may decrease as the mean growth rate increases in magnitude. I will discuss […]

Stephen Ellner (Cornell): An invitation to spatial coexistence theory

Stephen Ellner (Cornell), Peter Adler (Utah State), Giles Hooker (Cornell), Robin Snyder (Case Western): An invitation to spatial coexistence theory. Abstract: Previously in this series Sebastian Schreiber reviewed stochastic coexistence theory for infinite population models, based on long-term population growth rates of (infinitesimally) rare invaders. Nadav Shnerb presented progress on the challenges posed by demographic […]

Thomas Koffel (Michigan State): A niche theory of positive interactions

Abstract: Niche Theory has traditionally focused on competitive interactions. In this talk, we propose a general framework that expands the theory to positive interactions, such as facilitation and mutualism, using angular metrics of niche difference. We develop novel niche concepts such as the Allee niche and niche expansion, and illustrate them using a diverse set […]

James O’Dwyer (University of Illinois): Cooperation, Resource Exchange, and Stability

Abstract: Models of microbial interactions have been developed in recent years, drawing from taxonomic abundances via amplicon sequencing. Many of these models assume that dynamics through time are primarily driven by pairwise interactions between taxa, but with the drawback that how these interaction strengths may change with environmental context is less than clear. Here we […]

Géza Meszéna (Eötvös University): Coexistence, niche, adaptation and all that…

Abstract: Why are there so many animals? According an old idea, it is because there are so many different possibilities for life to adapt to. I’ll argue that it is still true, and truer than the suggested alternatives. The challenge is to establish the precise mathematical treatment at this level of generality without losing the […]

György Barabás (Linköping): Coexistence and parameter sensitivity in stationary aperiodic environments

Abstract: First, I present a method for calculating how average population densities respond to parameter perturbations when the dynamics are periodic, and show that this practical problem holds a strong connection with basic questions of coexistence. I then generalize this result to stationary nonperiodic density fluctuations. I finish by discussing the connection with existing formalisms […]

Cinzia Soresina (University of Graz): The influence of cross-diffusion in pattern formation: multistability and Hopf bifurcations

Abstract The Shigesada-Kawasaki-Teramoto model (SKT) was proposed to account for stable inhomogeneous steady states exhibiting spatial segregation, which describes a situation of coexistence of two competing species. Even though the reaction part does not present the activator-inhibitor structure, the cross-diffusion terms are the key ingredient for the appearance of spatial patterns. We provide a deeper […]

Chuliang Song (McGill University): An environment-dependent framework to study ecological networks

Abstract: Ecological networks—how species interactions are organized within ecological communities—are highly structured, which has motivated generations of ecologists to elucidate how these structures affect species coexistence. Unfortunately, we still do not have a clear and consistent answer about the link between network structure and species coexistence. A possible explanation is that most of the studies […]

Neo Martinez (Indiana University): Predicting Ecosystem Phenotype from Community Genotype: Can Allometric Trophic Network Theory Help Meet the Challenge?

Abstract: Theoretical ecology has investigated a series of concepts from stability and complexity through biodiversity and ecosystem function to coexistence and tipping points for which empirical data typically plays a less-than-satisfying role. To coax theoretical ecology towards increased empirical relevance and broader scientific synthesis, I propose that environmental biologists focus on predicting key characteristics of […]

Rafael D’Andrea (Stony Brook University): Counting niches: Can spatial patterns reveal niche partitioning in tropical forests?

Abstract: We investigate the idea that tropical biodiversity is maintained by a combination of niche segregation and niche sharing among species by asking whether tree species in Barro Colorado Island, Panama, fall into groups differing by the local conditions where they typically occur. We first group together species often found near each other, then show […]

Jacob D. O’Sullivan (Queen Mary): The emergent macroecology of Lotka-Volterra metacommunities

Abstract: For decades Lotka-Volterra community models have been used to try to understand how ecological interactions may drive community-scale properties such as species richness, network structure, and species abundance distributions; in short the various dimensions of biodiversity. Here I show how extending the basic community models into spatially and environmentally heterogeneous landscapes can help us […]

Mathew Leibold (University of Florida): Linking process to pattern in community assembly in diverse metacommunities

Abstract: I’m interested in exploring the degree to which theory on ‘disordered systems’ to community assembly can be linked to statistical methods of pattern analysis. Here, I hope to describe the problem and outline some possible approaches and answers. By doing so, I hope to generate interest and discussion on possible solutions. Zoom link: […]

Laura Dee (Colorado Boulder): Putting ecological theory to work for conservation

Abstract. Two grand challenges of our time are climate change and biodiversity loss. This talk focuses on the fundamental question of: to what extent can ecological theory help us understand the consequences of these global changes to inform conservation?  I will present two examples investigating this larger question: 1) the consequences of extreme events in boreal forests for ecological […]

Rachel Germain (UBC): Theory in service of empirical research: examples from experiments on the ecology and evolution of species coexistence

Science operates through a healthy feedback between theory and experiments. As an empiricist who uses theory for different purposes, I will begin by describing some barriers to more fully integrating theory into empirical research in ecology and evolution (and how to overcome those barriers). I will then describe two applications of theory in my own […]

Ehud Meron (Ben-Gurion): TBA

Zoom link: Past lectures are on the YouTube channel:

Watch recorded past seminars on our YouTube channel: