Effects of temperature and humidity on hydration and respiration in four strains of Drosophila

The four strains of Drosophila melanica studied were found to be most sensitive to low humidities during the first 19 hr after formation of the puparium. The mean fresh weights for the four strains were consistently different at all ages after puparium formation and at all conditions of temperature and humidity. The Forest Park strain, which showed greatest mortality at low humidity, had least body water per unit dry weight in the early pupal stage.A typical U-shaped oxygen consumption rate curve was found during the puparial-pharate adult period at all conditions of temperature and humidity. Differences among the strains were manifested at an earlier age under the more extreme environmental conditions.