Temperature, Effects on Development and Growth

This chapter explores the effect of temperature on insects' development and growth. The body temperature of most insects is linked to changes in ambient temperature. Insects are ectothermic and heterothermic, poikilothermic, organisms. Large dragonflies, hairy bees, and moths generate and maintain a high and stable thoracic temperature during flight. Temperature fluctuations are small in environments such as the tropical rainforest, caves, and large streams and water bodies. In most terrestrial habitats, the seasonal and diurnal temperature oscillations are considerable. The body temperature of insects can change rapidly by 10 °C or more when shade and direct sunlight alternate. Insects heat up by sunlight through basking behavior and thermal melanism. Preference for living at high temperatures, in warm regions or on a warm-blooded host, is called thermophily, whereas inclination to low temperatures is psychrophily usually soil and aquatic arthropods. Temperature within the species-specific physiological range determines the rates of metabolism, growth and development, and often exerts other physiological effects.