Growth trajectories of normal and JH-treated larvae of Manduca. JH-treated larvae (open circles) received a topical application of 50 μg methoprene (a stable JH analog) when they reached a weight of 3 g and again when they reached a weight of 6 g. Untreated larvae (filled circles) ceased feeding, purged their gut and entered the wandering stage on day 4. JH-treated larvae continued to feed for more than 2 weeks, but stopped growing after about 10–12 days, indicating that there is a physical limitation to the maximal size to which they can grow. Each curve is the mean of five larvae.
Nijhout et al. Journal of Biology 2006 5:16 doi:10.1186/jbiol43