Ecologia Concepts
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UPDATES

Time in Ecologia simulations is measured in updates. Each update, every tile is
updated and every animal gets its turn to move. How much physical time an update
requires depends on the speed setting (modifiable in the GUI) and the processing
power of the computer on which Ecologia is running.


TILES

The Ecologia world consists of a tile matrix. Each tile represents one discrete
area of ground that can be occupied by at most one animal or a spring (water
tile). Grass grows on tiles, providing food for herbivores. Depending on the 
humidity, the grass density may increase or decrease each turn. It also 
decreases when herbivores feed on the tile.

Tiles are colour-coded to show their current grass density: above 20%, the tile
is green. Between 0% and 20%, it is yellow; when there is no grass at all, the
tile is white. Herbivores cannot feed on tiles where the grass density is 0%.


HUMIDITY

Each tile has a humidity value, which is a combination of global and local
factors. The global humidity settings may be changed in the GUI, possible values
are 'Saturation' (+2), 'Wet' (+1), 'Dry' (0), 'Drought' (-1) or 'Severe Drought'
(-2). This setting simulates rainfall. Local humidity may be affected by the 
presence of water tiles (representing springs or oases). Each water tile waters
a 5x5 square around itself (i.e. sets the humidity in those squares to 
'Saturation').


ANIMALS

Animals are the main focus of Ecologia. As of version 1.0, there are two
species: herbivores and carnivores. Herbivores feed on the grass that grows on
each tile; carnivores hunt and eat herbivores. All animals have an energy level,
when this reaches 0, the animal dies. Movement and reproduction requires energy,
feeding restores it. Reproduction takes place asexually, when the animal's 
energy level exceeds a certain genetically determined mark. Animals die either
through losing all energy (for example in a drought) of old age (see the genome)
or (in the case of herbivores) by being killed in a fight with a carnivore.


GENOMES

Each animal has a genome that determines certain core characteristics. At the
start of a simulation, a user-defined standard genome is given to all animals of
a species. At reproduction, the parent genome is passed on to the offspring, 
potentially being mutated in the process.

All genomes encode the following characteristics (values differ according to
species, but the 'genes' are always the same):
    - mutation rate (percentage mutation probability per 'gene')
    - speed of movement (in tiles per turn)
    - stamina (used to simulate exhaustion caused by moving and fighting)
    - range of eyesight (in tiles)
    - efficiency of metabolism (this plays a role in how much energy
            the animal gleans from its food)
    - age limit (when reaching this age, the animal dies)
    - strength (important when hunting/fighting)
    - reproductive energy (the energy level at which it will reproduce)
    - age of sexual maturity (at which it can start reproducing)
    - gestation period (minimum time interval between reproduction events)
    - rate of reproduction (number of offspring per reproduction event)