Simplify the following text for a Grade 12 native English-speaking person.
Original: The idea of the phenotype has been generalized by Richard Dawkins in The Extended Phenotype to mean all the effects a gene has on the outside world that may influence its chances of being replicated .
Simplified: The idea of the extended phenotype has been developed by Richard Dawkins to mean all the effects a gene has on the outside world that may influence its chances of being inherited .