I certainly know my share of gays who have moved to San Francisco, even if only for a summer or two.  I imagine that if this could ever be reduced to cause/effect, it would be pretty complicated, though.  I'm not going to hold my breath.

In fact, there are times when I look at science journals, particularly social science ones, and think, "Thank you very much, Captain Obvious."  You know, it's one of the only annoying things about science.  Even if something is patently obvious, you need to make absolutely certain that it is what it appears to be.  So, you sometimes have to do studies that seem pretty trivial, or even wasteful.

I remember reading an abstract that amounted to this:  Babies born to women who lived in highly polluted areas during gestation are less healthy than those born to women who lived in largely unpolluted areas during gestation.

No shit.

The thing is, though, this kind of study can still give us useful information if we do manage to learn something about the underlying causes.  For instance, isolating a particular illness because of studying pollution in fetuses might lead to a discovery about a particular gene that expresses because of pollution, which might lead to something monumental in genetics.  You never know.