Water vapor absorption in arthropods by accumulation of myoinositol and glucose
Hydrophilic soil arthropods have been thought to respond to soil desiccation exclusively by migrating to deeper soil layers. Numerous studies have shown that their survival below 90 percent relative humidity dry weight, is limited to hours. However, little attention has been paid to physiological adaptations to more realistic desiccation regimes, such as at the permanent wilting point of plants (98.9 percent relative humidity). A water vapor absorption mechanism is described that allows a common soil collembolan, Folsomia candida, to remain active down to below the permanent wilting point. A reevaluation of the water physiology of this widespread and diverse animal group is required.
Bayley
M
National Environmental Research Institute, Department of Terrestrial Ecology, Vejlsovej 25, Post Office Box 314, DK-8600 Silkeborg, Denmark.
Holmstrup
M