CHANGES IN TEMPERATURE TOLERANCE DURING LIFE CYCLE OF CALLIPHORA ERYTHROCEPHALA

The tolerance to high temperature of Calliphora erythrocephala has been measured throughout the life cycle. A method of measuring the heat death point of active and immobile stages of the insect is described. The egg stage is most sensitive to temperature and the puparium stage most resistant. In the 1-day-old emerged adult the heat death point is as great as in the 1-day-old puparium. However, this high adult tolerance is lost in the first 5 days after emergence. It is suggested that the changes in the heat death point can be correlated with changes taking place in enzymes during development. Evidence is also presented that these changes may be part of more general physiological changes in resistance to both physical and chemical stresses. © 1969.