What is the predator prey model?

The predator-prey model is a mathematical representation used to describe interactions between two species within an ecosystem where one species is the predator and the other is the prey. This model illustrates how the populations of these species change over time based on their interdependent relationships.

Steve Keen discussed a variant known as the Goodwin model, initially inspired by the classic Lotka-Volterra model, which uses simple differential equations to describe the dynamics between predators and prey. In the example given, grass is the prey and cows are the predators. More grass leads to more cows, but as the cow population increases, they consume more grass, which then leads to a decrease in the grass population, thereby reducing the food available for cows which then leads to a decline in their population. This results in cyclic dynamics between the two populations 1 .

Such models are foundational in ecological studies and are used to help explain and predict fluctuations in species populations over time.