David Campbell wrote (6/30/97):
...does anyone know what cues the transition to overwintering stages in the
taxa that switch modes (e.g., aphids going from parthenogenesis to sexual
reproduction to produce durable eggs)?
I don't know either, but I have a suggestion. The people who might know are
researchers on insecticides. They study insect behavior in order to find
vulnerable stages of the life cycle.
Andrew K. Rindsberg
Geological Survey of Alabama