[kqr2]

Is there any explanation from game theory as to why a slight imbalance causes such an exaggerated effect?

It makes sense that since there are more men, women get pickier, so paradoxically there appears to be less good men available to women.

What does game theory predict in such a situation?

[californiaguy]

http://www.slate.com/id/2188684/

The eligible bachelor paradox.