Cover Caption

To answer the question of whether phylogenetic relatedness can act as a proxy for insect response to Bacillus thuringiensis, the susceptibility of eleven colonies of lepidoptera representing different families, genera, species and colonies was compared. While species within genera had similar responses, genera within families did not. Two laboratory colonies of one species differed, suggesting a colony divergence. We conclude that caution is needed in using surrogate species to assess Bacillus thuringiensis effects on non‐target insects. (see pages 803‐812). Imaged by E. P. J. Burgess, Plant & Food Research, New Zealand