Fisher's equation

Fisher’s equation models how a species spreads across space over time. It combines two key ideas: growth and movement. The "growth" part describes how the population increases locally, while the "movement" part captures how individuals disperse to new areas. The equation predicts a stable wave of invasion, moving at a specific speed, called the invasion or wave speed. This speed depends on factors like the population’s growth rate and the ability to disperse. Overall, Fisher’s equation helps ecologists understand how populations expand into new territories over time.