Larval Habitat Suitability and Oviposition Preference in Three Related Butterflies

A simple hypothesis about habitat choice by ovipositing butterflies is that females prefer to lay their eggs on plants in habitats where juvenile growth and survival are best. This hypothesis was evaluated by studying 3 Aristolochia—feeding swallowtail butterflies (Papilionidae: Troidini). Results show that the eggs and larvae of all 3 butterfly species survive significantly better in shady habitats than in sunny habitats. Pupal survival is similar in the 2 habitats for at least 1 species. Larval growth rates were similar in the 2 habitats for all 3 species. Thus, for all 3 species shady habitats appear to be more suitable for juvenile development and survival than sunny habitats. Only Parides montezuma lays most of its eggs in shady habitats, however; Battus philenor and B. polydamus females lay most of their eggs in sunny habitats. The original hypothesis is therefore not upheld by this study. Three alternative explanations for the discrepancy between the relative suitability of habitats for the juvenile stages and habitat choice by ovipositing females are suggested.

Duke Scholars

Author Mark D. Rausher Biology