none Smith Trail (1980) suggested that this system (Euphydrayas phaeton caterpillars and their parasitoids) is appropriate for testing the hypothesis of host suicide, and that parasitized hosts advertise themselves to predators and, thus, contribute to increased survivorship of their nonparasitized siblings. However, it appears from this study, other life-history information cited on this system, and data cited on the E. editha -parasitoid system that host suicide is unlikely in such nymphalid butterflies. Rather, these observations support the hypothesis that the behavior of parasitized larvae prior to parasitoid emergence may increase the parasitoids' chances of escaping predation and parasitism. Consequently, behavior of parasitized hosts in host-parasitoid systems may contribute to higher survivorship of parasitoids just as the behavior of hosts parasitized by true parasites promotes acquisition by definitive hosts and, thus, parasite survival. Parasites diseases and disorders; Parasites; Insect parasites; Hosts; Insect hosts; Host parasite relationships Euphydryas phaeton (Nymphalidae); Hymenopteran parasites; Apanteles euphydryidis; Hyperparasitism; Hymenopteran prevalence on Apanteles (Hymenoptera); Consequences of modified behaviour of primary host; Reaction of host to parasite; Apanteles euphydryidis (Hymenoptera); Modified host behaviour, consequences for parasitoid survival Apanteles euphydryidis (Braconidae); Lepidopteran hosts; Euphydryas phaeton; Hyperparasitism; Hymenopteran hyperparasite prevalence in Euphydryas (Lepidoptera); Prevalence; Hymenopteran hyperparasites in Euphydryas (Lepidoptera); Consequences of modified behaviour of primary lepidopteran host; Reaction of host to parasite; Euphydryas phaeton (Lepidoptera); Modified host behaviour, consequences for parasitoid survival