Figure 3
A correlation between peaks of ecdysteroid activity and the formation of macrochaete precursors. The graph shows the pulses of 20E experienced by D. melanogaster during larval and pupal life. Adapted from (Riddiford, 1993) and (Warren et al, 2006). A small pulse during the third and last larval instar causes wandering of the larva and glue synthesis. Pupariation is initiated at five days of development during a peak of 20E (dotted line). The temporal windows during which macrochaete or microchaete precursors are specified are shown as black rectangles. Note that macrochaete precursors form before, and microchaete precursors after, the 20E pulse corresponding to pupariation.
