Survival of step and ramp changes of temperature by the Queensland fruit fly, Dacus tryoni

ABSTRACT. Survival time at subzero temperatures is related to both long-term thermal history and the rate at which the insects are cooled. Insects cooled at one degree per hour survive for up to 3 times as long at a given test temperature than do insects cooled at 1C/min. Survival times are significantly shorter than times taken to freeze. Survival time at an extreme high temperature is related to long-term thermal history but the rate of heating makes no difference.