Depends what your studying on
Decrease in the fertility of soil
Citizens can have an initiative which can put your law on the ballot to be voted on which in the end with enough signatures or votes your law may become true and realized as a real law.
The answer to this question is active Genotype environment.
Active genotype environment interaction happen when a behavior from a certain individual will trigger responses from around that individual's environment. One example of this is when someone encourages her peers (her behavior will trigger other people to behave a certain way)
