Fig. 4. Acquisition of larval reflexes in prematurely hatched Drosophila embryos. (A) Touch response. Average touch response scores are shown (and s.e.m.). Each embryo was tested 10 times (giving a score out of 40) and 10 embryos were tested at each developmental age. Embryos were selected at tracheal filling (18.5 hours AEL) and aged on agar plates at 25°C, then prematurely hatched just before testing). (B) Acquisition of self-righting. Embryos were rolled upside down onto their dorsal surface, and time to self-right recorded. Embryos were tested three times and 10 embryos were tested at each developmental age (embryos at different developmental stages were selected as in A).