Fluctuating Asymmetry in Colophospermum mopane Leaves and Oviposition Preference in an African Silk Moth Imbrasia belina

Abstract

Fluctuating asymmetry in plant metric traits is often correlated with individual plant quality, and may act as a cue to pollinating or phytophagous insects. If ovipositing insects select hosts on the basis of perceived host quality, then we may expect a similar correlation between oviposition preference and the degree of fluctuating asymmetry. Fluctuating asymmetry in Colophospermum mopane leaf length was comparable to that found for other plants, but varied widely within individual trees. Oviposition site choice by an African silk moth Imbrasia belina showed no significant relationship to fluctuating asymmetry in leaf length of C. mopane, their principal host tree in the area. There was weak evidence, however, of a positive relationship between leaf asymmetry and clutch size. The lack of a significant relationship between oviposition site choice and host tree leaf asymmetry in this study may be due to constraints imposed by I. belina life-history traits and to host tree abundance, rather than a lack of potential benefits from host discrimination based on leaf fluctuating asymmetry.