Are you looonely tonight?

It may not just be a song, it may be you. Twin research on 8,000 pairs of identical and fraternal twins indicates a moderate- to fair-sized correlation for a hereditary tendency toward loneliness. As I’ve noted in posts and responses to commenters here, I do believe there is a valid discipline of evolutionary psychology, while I am at the same time far and away from believing every claim of its biggest boosters and their just-so stories.

So what’s the evolutionary advantage of loneliness, if this isn’t just a spandrel from genes coding for a tendency to something else?

The researchers suggest that loneliness may stem from prehistoric times, where hunter-gatherers may have deliberately shut themselves away from others so they did not have to share food.

That would have meant they were better nourished and therefore better able to survive and have children.

But loneliness would already then, and certainly today, does have its downside, the researchers caution. Then:

But they added that the strategy had a downside, in that it also developed dispositions towards anxiety, hostility, negativity and social avoidance.

And now:

Loneliness has been linked to heart disease as well as emotional problems, such as anxiety, self-esteem problems and sociability.

One naysayer psychologist offers a caution:

Dr Arthur Cassidy, a psychologist at the Belfast Institute, said people could learn behaviours from their families.

“They may have a very pessimistic outlook and interpret things in a very negative way, so people can learn to become pessimistic and therefore to become lonely.”

Actually, all Dr. Cassidy does it to show that he apparently doesn’t recognize how twin studies are controlled, through studies of adopted twins, etc., to control for environmental influences such as that as much as possible. Besides, it is likely that as much of a sociological influence toward loneliness would come from outside the family structure as from within.