Dr. James Orr
Theoretical Ecology | Global Change Ecology | Microbial Ecology
Responses of ecological communities to stressors
Hello there! I’m an ecologist interested in how stressors impact the diversity, stability, and functioning of ecological communities. I’m particularly interested in the interactions between species that lead to complex dynamics and in the interactions between multiple stressors that make predicting biodiversity responses to global change across time and space so challenging.
I use a combination of mathematical theory, experimental ecology, and research synthesis in my work. Although much of my research focuses on fundamental questions in theoretical and community ecology, I am also interested in applied questions in the fields of global change biology, environmental science, and microbiology.
I was recently awarded a Discovery Early Career Researcher Award from the Australian Research Council to study how the temporal synchronization of antibiotics and phages impacts the ecology of bacterial communities and the evolution of antimicrobial resistance. This is part of a more general research agenda to understand how multiple stressors can be temporally manipulated to maximize or minimize ecological impacts.
On this website, you can find a list of my publications (categorized by topic) and a collection of resources that I’ve produced for other scientists to use.
Experience
ARC DECRA, Independent Fellowship
University of Queensland, Australia, 2025 - 2028
My research project leverages novel ecological theory to understand how the temporal synchronization of antibiotic and phage exposure influences the ecology and evolution of bacterial communities. I am hosted in Dr. Andrew Letten’s microbial ecology research group. I also work closely with Dr. Siobhán O’Brien at Trinity College Dublin and Dr. Jeremy Barr at Monash University.
Postdoctoral Researcher
University of Queensland, Australia, 2024 - 2025
I was a postdoc in Dr. Andrew Letten’s microbial ecology research group. I worked on questions in fundamental ecology using mathematical theory (e.g., consumer-resource theory, coexistence theory) and experimental microbial ecology (e.g., using chemostats).
Postdoctoral Researcher
University of Oxford, UK, 2021 - 2024
I worked in Dr. Michelle Jackson’s aquatic ecology research group for three years. I used ecological theory, freshwater mesocosm experiments, ecological modelling, and synthesis approaches to study global change impacts across multiple spatial scales, with a particular focus on the temporal dynamics of stressors.
PhD in Theoretical Ecology
Trinity College Dublin, Ireland, 2018 - 2021
My PhD thesis was on the mechanisms of stressor interactions. I studied mathematical and theoretical ecology, multiple-stressor research, and freshwater ecology under the supervision of Dr. Jeremy Piggott, Dr. Andrew Jackson, and Dr. Jean-François Arnoldi.