I can imagine plenty of situations where passively being sad and not going out and attempting to be productive are safer. Maybe depression is an alternative to cabin fever? Long hard winters are easier to survive if you're too depressed to go out and possibly freeze to death and instead stay in your cave/yurt eating the most easily accessible saved food. That would explain the evolutionary value of Seasonal Affective Disorder.

tut13y20

That would explain the evolutionary value of Seasonal Affective Disorder.

There are more people with SAD who get depressed in the spring than in early winter or the darkest part of winter.

0NancyLebovitz13y

Another thought from hypothesis land: maybe a little depression is a chance to retire and regroup, but in the original environment, there was more that would pull people out of depression-- social contact and work that obviously needs to be done. This is about mild-to-moderate depression, though. Major depression seems to be different, and not good for anything.

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