Bryophytes may be desiccation tolerant, surviving dry tissues and beginning photosynthesis upon
rehydration, or they may be drought avoiders, using structural adaptations and life cycle stages to escape having a dry leafy plant. The presence of a central strand does not seem to correlate with the degree of internal conduction, but habitat does. Xeric bryophytes are more likely to have greater internal conduction and faster external conduction than mesic and hydric taxa.
It is possible that the central strand may serve as a water reservoir in some taxa.