by Hanna Rosin

A very interesting article in Scientific American this week explores new research showing that depression may be a mental adaptation that helps promote sharper analytical thinking.  The research begins with the question: Why isn't depression more rare? Maybe, like obesity, it afflicts us because modern conditions are so different than the ones in which we evolved. But no, apparently depression is common to all cultures, even small scale, isolated ones.

One strain of research points to adaptive advantages that come from depression:

So what could be so useful about depression? Depressed people often think intensely about their problems. These thoughts are called ruminations; they are persistent and depressed people have difficulty thinking about anything else. Numerous studies have also shown that this thinking style is often highly analytical. They dwell on a complex problem, breaking it down into smaller components, which are considered one at a time.

If that's true, I say meh to evolution.