Egg Deposition Patterns in Butterflies: Why Do Some Species Cluster Their Eggs Rather Than Deposit Them Singly?

Abstract

Egg clustering is found in certain butterfly groups such as nymphalids, pierids, and acraeids, but rarely in papilionids, satyrids, danaiids, riodinids and hesperiids. The occurrence of butterfly species which deposit eggs in clusters is apparently more common than the literature indicates; data on egg deposition patterns in natural populations of nymphalids in North America, in particular for Phyciodes, Chlosyne, Euphydryas and Nymphalis spp., may support this conclusion. Egg deposition patterns are a response to the structural and ecological characteristics of the larval host plants. The advantages of egg-clustering appear to be related to aposematic coloration in butterflies (eggs, larvae and adults), although a particular stage in the life cycle of a butterfly that lays eggs singly may be aposematically colored.