Species are added to the selected biome by first selecting the species in the Species menu and then adding the species using the Add Species button. Species that have been added to a biome appear in the Species Tracking section of the Setup menu along with an initial population for the species. Other variables and actions that can be performed in the Species Tracking menu include the following:
Population. When a species is added to a virtual biome and listed in the Species Tracking list, the initial population is shown next to the species. This initial population can be changed by clicking and editing the number.
Excess Food. In order for a species to survive in a virtual biome it must have food to eat. For plants, the nutrient and toxicity abiotic variables control this, but for consumers this food source is assumed to be another species that has been added to the biome. If an appropriate species has not been added for a consumer, then that consumer will die off quickly from starvation. For consumers that are listed in the Species Tracking projector, an Excess Food check box is added to the right of the species. Checking this box indicates that the species has excess food in the virtual biome and a species acting as a food source does not have to be added.
Edit Species Pencil. Clicking on the pencil to the right of a species listed in Species Tracking will turn on an Edit Species menu. A large list of variables that are used to define the selected species in the simulation can be adjusted. Any of the listed variables can be changed to observe how they affect the population of all of the species that have been added to the virtual biome. Any changes that are made are temporary and only remain until the species is removed. A description of the variables is given in the The Simulation section of the Help menus.
Delete Trashcan. A species can be removed from the virtual biome by clicking the trashcan to the right of the species.
Population. During the course of an Ecology experiment, the population of one or all of the species in the virtual biome can be changed by clicking on the Population button in the Controls display on the left. This button is used to represent various types of migration into or out of the biome. The size of the migration is specified as an absolute number or as a percent and a “+” represents migration into the biome and a “-“ represents migration out of the biome. The drop down list is used to select the migration of a specific species or All of the species.
Catastrophe. The Catastrophe button works identically to the +/- Population button except the direction of migration is only out of the biome. This button is used to represent catastrophes that could affect a biome such as flooding, fire, sudden drought, etc.