Processes

The model iterates as follows:

Births

The number of births at a time step is determined by the amount of resources on the landscape.This rate multiplied by the number of rabbits defines the number of births. Agents are distributed in groups (types) according to the proportion of types in the population.

Movement

The agent analyzes the amount of resources in the cells around it according to the their vision and attempts to move to cells not occupied by other agents. They always seek the cell with largest amount of resources. When agent moves to this cell the amount of resources given by the parameter attribute “Resources spent to move” is subtracted from the stock of calories.

Intake

After the movement the agent consumes the amount of resources up to the limit of its absorptive capacity according to the parameter “Maximum absorption of resources”. This value is subtracted from the corresponding cell in the map of resources and added to the agent’s stock of calories.

Landscape recovery

Recovery occurs every time step according to the current amount of resources in the cell and the maximum capacity of resources using a logistic function.

Death

There are two causes of death:

-Starvation: lack of enough energy to stay alive. It occurs when the agent's stock reaches zero calories.

-Age: the number of deaths in a time step is defined by a value that represents the average of a normal function of the agent lifespam. The model uses a sthocastic draw to determine whether the agent lives or dies.

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