Population cages of wild-type, fertilized females were maintained at 25oC. Embryos were collected on apple juice agar plates in 30m windows, aged at 25oC for the required time, then dechorionated. For each sample, about 20 ul embryo pellets were transferred to PBS buffer for lysis. To assess the homogeneity of embryonic stages of each collection, about 10% of the sample was fixed and staged. The remainder of the sample was snap-frozen. For each time point, samples were collected in quadruplicate.