Bernard Roitberg

Professor Emeritus

Behavioural & Evolutionary Ecology



  • BSc, University of Massachusetts
  • MSc, University of Massachusetts
  • PhD, University of Massachusetts

Areas of Research

Research Interests

The primary focus of our research is on decision making in insects and plants. As such, we employ an evolutionary perspective to elucidate how and why organisms decide with whom to mate, how long to search for hosts within patches, which hosts to attack, how many eggs to lay, the size and/or quality of offspring and the scheduling of such events.
Our approach to answering such a broad range of issues has been to first develop a theoretical framework based upon biological principles and then to derive testable hypotheses from the theory. This approach has proven very successful in explaining several apparently paradoxical phenomena such as superparasitism in fruit flies and host suicide in aphids. A large part of this success comes from our consideration of organisms as dynamic individuals whose physiology and experience influence their response to their environment.
Finally, we have recently turned our attention to higher levels of organization such as spatial patterns of parasitism, parasite-host co-evolution, evolution of marking pheromones, evolution of movement-related behaviours, landscape ecology and disease dynamics. Here our approach differs from standard methods in that we ask what the consequences of individual behaviours might be on the aforementioned higher order processes. Again, our success derives from carefully blending theory and experiment.

Structure functions that describe probability of fly encounters with fruit at different distances from a randomly chosen fruit cluster at six different sites near Vancouver. These functions can be used to calculate the impact of habitat structure on fly behavior and reproduction. From Roitberg and Mangel Oikos: 80: 234-40


Bernard D. Roitberg publications


This instructor is currently not teaching any courses.