the increase of something required by an organism has a positive impact on that organism 's survival
spouse has effect_of_happiness positiveness is amount. positive_stimulus is stimulation. evolution has not effect_of_creating_new_species phototroph is living_organism. joy is positive_stimulus. positive_outcome_of_undertaking is not success. impact is consequence. positive_outcome_of_undertaking is success. evolution has effect_of_creating_new_species