Fig. 2From: Big or fast: two strategies in the developmental control of body sizeAlternative control mechanism for body size. Sigmoidal growth curves with two different mechanisms that stop growth. a In the presence of juvenile hormone (JH), as in Manduca, ecdysone secretion cannot occur until JH has disappeared. The decline of JH begins when larvae pass the critical weight (CW). b In the absence of JH, as in Drosophila, ecdysone secretion follows attainment of the minimum viable weight (MVW) after a delay called the molt timer, whose mechanism is not yet understood. This leads to an earlier cessation of growth and a smaller body size than occurs when JH overrides the MVW mechanismBack to article page