The effects of a multispecies sequential diet on the growth and survival of a tropical polyphagous caterpillar

Hylesia lineata Druce (Lepidoptera: Saturniidae) caterpillars are highly polyphagous at the individual level. I examined the effects of a multispecies sequential diet on the performance of the larvae. The experiment included three natural hosts respectively —Casearia corymbosa HBK,Thouinia paucidentata Radlk., andErythroxylum havanense Jacq — used by ovipositing females in proportion as expected by their abundance;C. corymbosa andE. havanense representing the most and least abundant hosts respectively. All possible two-host and single-host diets were tested. Larval survival to the pupal stage (as protected by a field cage) did not differ among all diets. Also, for females, regardless of the identity of the initial host, the final weight and the developmental time depended entirely on the nature of the final host. Male performance, in contrast, only differed in terms of developmental time but again the initial host did not affect the final result. It was concluded that a host switch early in the development of the caterpillars does not affect further growth on the other host plants. Caterpillars that finished their development onE. havanense reached small sizes but females devoted a larger proportion of their resources to egg biomass; as a result female fertility was similar among females regardless of their feeding history. I concluded that the caterpillar's abilities and the female compensatory flexibility may oppose selection for a strong preference hierarchy in the female ovipositing behavior.