Rosalyn Rael Tulane University
Tulane/Xavier Center for 
    Bioenvironmental Research
627 Lindy Boggs Center for                             Energy and Biotechnology
6823 St. Charles Ave.
New Orleans, LA 70118




Rosalyn Rael


I am a mathematical biologist interested in the evolution of ecosystems, the interactions among organisms within them, and disease dynamics at the interface of ecology and human society. Currently I am a postdoctoral fellow at the Tulane/Xavier Center for Bioenvironmental Research, where my work involves modeling the dynamics of a pathogen reservoir host species to assess changes in the distribution of human exposure risk through time and to investigate the societal and ecological impact of disease intervention and control strategies.

Formerly I was a postdoc in Annette Ostling's Lab in the department of Ecology and Evolutionary Biology at the University of Michigan. I also have ongoing collaborations with the Pacific Ecoinformatics and Computational Ecology Lab in Berkeley, CA.


Community abundance patterns

Can species abundance patterns reveal underlying niche structure? Neutral dynamics are based on demographic stochasticity and immigration and niche dynamics are generated by trait differences that affect fitnesses of competing populations. To explore the differences in abundance distribution patterns that arise in communities with these two types of dynamics, I use stochastic metapopulation competition models. 

Collaborators: Annette Ostling, Gyuri Barabas, and Rafael D'Andrea
evolved web

Food web evolution

Food webs are complex networks of who eats whom in an ecosystem. By modeling the dynamics of these systems and the evolution of these structures through time, we can explore the impacts of speciation and adaptation on properties of food webs. I am interested in studying how species survival depends on the ecosystem context in which one arises, and how it in turn, affects the species already present. By combining evolution with ecological dynamics, we can study stability and resilience of food webs in a more realistic setting.

Collaborator: Neo Martinez

Evolution of competition

Evolution can change the expected outcome of competition. When species are able to adapt quickly in the presence of competitors, two competing species may be able to coexist stably, when otherwise one would be expected to competitively exclude the other. This scenario requires certain conditions on the speed of evolution and the competition coefficients.  We used evolutionary game theory to model this and other changes that may arise in competitive systems due to evolution. These models are inspired by and compare favorably to scenarios that have arisen in competition experiments with Tribolium flour beetles.

This is my dissertation work, advised by Jim Cushing and Tom Vincent in collaboration with Bob Costantino at the University of Arizona.