*************** ANNOUNCEMENT **********************
* University of Utah Mathematical Biology Seminar *
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Wednesday, March 31 at 4pm in INSCC 110


Speaker: Gary Belovski, Utah State University Mathematics

Title: Alternative States and Nonlinear Dynamics for an Insect
Population in the Field

Abstract: 

Some population models predict that populations can shift between
alternative states: predator- or resource-limitation (e.g.,
competition for food). Which alternative state is observed depends
upon initial densities and shifts between states can occur
spontaneously if the oscillations produced by nonlinear dynamics are
severe. Field experiments with grasshoppers that vary initial density
and predation indicated that alternative states exist and that
nonlinear dynamics occur. In some years, this produces
predator-limitation and in other years, resource-limitation. Observed
population dynamics indicate that the potential for alternative states
and nonlinear dynamics is more likely than predicted by the model.