Host plant preferences in the comma butterfly (Polygonia c-album): Do parents and offspring agree?

We studied the host plant preferences of parents and offspring in the comma butterfly, Polygonia c-album (L.), from the Stockholm area of central Sweden. Females of the spring and summer broods were given a choice of four host plants (Urtica dioica, Ulmus glabra, Salix caprea and Betula pubescens) in flight cages, whereas their newly hatched larval offspring were given a choice of leaf samples from the same plants in petri dishes. Disagreement regarding ranking of host plants among parents and offspring could indicate trade-offs between adult and offspring fitness correlates. In the case of P. c-album, we predicted that if such trade-offs are weak, the choices of parents and offspring should be in agreement, because a good correlation between female host plant preference and offspring laboratory performance has previously been found. Both female and larval plant preferences differed between broods. The preferences of females and offspring were in close agreement, also differing in the same way between broods. Larvae tended to avoid plants low in the preference hierarchy (Salix- and Betula) to a higher degree than females. We found no evidence of a genetic correlation between the preferences of parents and offspring. We propose that comparisons between the preferences of parents and their offspring could be an important complement to the more common studies on preference-performance correlations, giving additional clues as to how insect-plant interactions evolve.