Thats what I don't understand, how mental illness are increasing...

Going with this whole evolutionary theory, if someone is say Depressed, or anxious, or whatever... chances are they would be less motivated to go out and build relationships and have a family (hypothetically). So over time.. it would make sense that their genes would have LESS of a chance to be passed on than someone who is say not depressed.

Then again, I suppose there is the whole nature vs nurture debacle, and situations can arise that would cause certain people (people who maybe wouldn't have a predisposition to become depressed), to actually become depressed. In that case, it wouldn't be a matter of heredity per se, but the situational factors that could be of contribution.

Maybe thats one of the reasons mental illness's are on the rise ...