Stochasticity, invasions, and branching random walks.
We link deterministic integrodifference equations to stochastic, individual-based simulations by means of branching random walks. Using standard methods, we determine speeds of invasion for both average densities and furthest-forward individuals. For density-independent branching random walks, demographic stochasticity can produce extinction. Demographic stochasticity does not, however, reduce the overall asymptotic speed of invasion or preclude continually accelerating invasions.
Kot
Mark
M
Department of Applied Mathematics, Box 352420, University of Washington, Seattle, WA 98195-2420, USA. kot@amath.washington.edu
Medlock
Jan
J
Reluga
Timothy
T
Walton
D Brian
DB
D011336:Probability; D013045:Species Specificity; D013269:Stochastic Processes