Adult flies are stress sensitive. There are two temperature-sensitive periods during development, one during the second larval instar and one spanning the interval from late third instar to pupariation. In addition adults show temperature-sensitive lethality; they die 4-8 days after eclosion at 29^oC. Larvae show temperature-sensitive lethality during the second and third instar. Mosaic analysis suggests that bilateral lethal foci for the adult lethality exist, which appear to be diffuse and "domineering" and span much of the ventral nervous system. Individual legs of mosaics sometimes become paralysed, there are probably separate foci for paralysis of individual legs.

Severely paralyzed by mechanical shock and also constitutively inactive; adults become hyperactive under crowded conditions (Homyk et al., 1980). A temperature-sensitive developmental lethal, with two temperature-sensitive periods, one primarily during second larval instar and another ranging from late third instar to early pupation (Homyk et al., 1986); also an adult lethal, such that about half the flies are dead after five days exposure to 29^oC (Homyk et al., 1986). From analysis of high-temperature-induced adult death and leg paralysis in mosaics, the foci of the former concluded to be diffuse, "domineering," and near posterior region of ventral blastoderm; regarding the behavioral phenotype, individual legs observed to be paralyzed, or not, in these gynandromorphs and from these data it was also inferred that the paralysis foci are rather near that for lethality.