Progresses of Cryoecology and Immune Stress and Defense in Insect

The effect of temperature on physiology mediates many of the challenges that insects face under climate change. Insect immunity is thermally sensitive and, as such, environmental change is likely to have complex effects on survival, disease resistance and transmission. The effects of temperature on immunity will be particularly profound in winter because cold and overwintering are important triggers and regulators of insect immune activity. Low temperatures can both suppress and activate immune responses independent of pathogen, which suggests that temperature not only affects the rate of immune responses but also provides information that allow overwintering insects to balance investment in immunity and other physiological processes that underlie winter survival. Changing winter temperatures are now shifting insect immunity, as well as the demand for energy conservation and protection against parasites. Whether an insect can survive the winter will thus depend on whether new immune phenotype will shift to match the conditions of the new environment, or leave insects vulnerable to infection or energy depletion. This paper synthesize patterns of overwintering immunity in insects and examine how new winter conditions might affect insect immunity.