Experimental Studies on the Duration of Life. XII. Influence of Temperature during the Larval Period and Adult Life on the Duration of the Life of the Imago of Drosophila melanogaster

Abstract

Drosophila reared at 18[degree] C. is distinctly larger than when reared at 28[degree] C. Pigmentation is different in the 2 cases, notably with reference to the 7th tergum. Females were longer lived than [male] [male] in all these experiments. The difference in duration of life between the sexes diminishes as the temp. during imaginal life increases, regardless of the temperature during development. Higher temperature during imaginal life decreases the duration of life. The relationship between duration of life and temp. is exponential. For the range 18[degree]-28[degree] the temp. coefficient for duration of life had, as average figures, the following values Q 10 = 2.07, and [mu] = 12717.3. The relative or proportional influence of temp. on body size and on duration of life was of the same order of magnitude. This furnishes confirmatory evidence to the theory that an important factor in determining the duration of life is the rate of energy expenditure during life.