Fig. 1. Patterns of (A) survival, (B) stadium duration and (C) pupal dry mass for final-instar S. littoralis caterpillars confined to one of 20 no-choice diets varying in protein:carbohydrate (P:C) ratio (35:7, 28:14, 21:21, 14:28 and 7:35) and in the quality of dietary protein (0%, 20%, 50% and 80% replacement of casein-based protein mix with the low-quality plant protein, zein). Values are means ± 1 s.e.m. (N=6–10).