Despite American taboos, cousins are marrying each other in states where it's legal, and, with the help of studies that show little risk to their offspring, they're starting to come out of the shadows, with sometimes heartbreaking results.
This week, perhaps as a tribute to the late, great Bernie Mac, the "Explainer" on Slate takes on the universal taboo of "maternal incest" in insults - think "motherfucker." Why is this still the worst of the worst?
Nowadays, women can do a lot of things. We can hold high offices, wear trousers, ask men out, drink whiskey in public. What can't we do? Wink. Women winking is always, always inappropriate. Why?