Drosophila melanogaster; FEEDING-RATE; Selection for increased resistance to parasites relationship; NATURAL-SELECTION; Increased immunological resistance to hymenopteran parasite; Trade off with competitive ability associated with reduced feeding; HYMENOPTERAN-PARASITES; Asobara tabida & Leptopilina boulardi; Selection for increased resistance effects on larval competitive ability; IMMUNE-LIKE-REACTIONS; Larval response to hymenopteran parasite egg; Selection for increased resistance effects on competitive ability & feeding; SURVIVAL-; Larvae, intraspecific competition effects; Association with level of resistance against hymenopteran parasites; INTRASPECIFIC-COMPETITION; Larval ability, trade off with increased parasite resistance; Feeding rate relationships Asobara tabida; Leptopilina boulardi; DIPTERAN-HOSTS; Drosophila melanogaster; Resistance in host association with reduced feeding & competitive ability none