Simplify the following text for a Grade 9 native English-speaking person.
Original: Kin altruism is the term for altruistic behavior whose evolution is supposed to have been driven by kin selection .
Simplified: `` These processes I will call kin selection and group selection respectively . Kin selection has been discussed by Haldane and by Hamilton ... By kin selection I mean the evolution of characteristics which favor the survival of close relatives of the affected individual .