The decision to take the same surname is one way same-sex couples are rehabilitating—repurposing, you might say—some of the most ancient marital traditions. Name-change dates back to the common-law doctrine of "coverture," when a bride assumed her husband's name and legal identity and, in what is called "civil death," ceased to exist as a separate legal person. Feminism inspired some women to reject this tradition—about 10 percent of women, according to studies, decline to take their husband's surname—taking a stand for autonomy but contributing to a world in which teachers are sometimes unsure which children belong to which parents, and the generation who grew up with hyphenated names must decide whether to exponentially burden their own offspring. In embracing the standard option, same-sex couples are lending it a new, radicalized flavor. Not only lesbian brides but some gay grooms change their names; whether this will pave the way for straight men remains to be seen. Name-changing may turn out to be something men do when partnering with men, but not when partnering with women. The number of straight men who change their name upon marriage, remains so tiny as to be imperceptible.

In same-sex couples, decisions around who will do the name-changing and who will do the name-losing have to be made according to something other than gender. "There's more of a conversation" in many same-sex partnerships, says Suzanne A. Kim, a professor at Rutgers School of Law-Newark.

"For us it was about being a family," says Bev Uhlenhake, who lives with her wife, Sue, near Bangor, Maine. The women have three children, conceived by sperm donor and carried by Bev. To make it clear they have equal parental status, Bev was inclined to let Sue's be the family surname. But there was one problem: Bev is tall—6' 2"—and Sue's maiden name was Teeney. There was no way Bev was going to go through the rest of her life fielding height jokes, or subject their kids, already "taller than your average bear" to that playground torture.

"I know there's a lot more altruistic reasons for taking one name over the other, but that's why we made the decision," said Bev. "I had been hoping and praying since I was old enough to spell my last name that I would marry someone with the last name of Smith. But that didn't happen."

Lesbians also have to come to terms with "wife," a word that for many women remains ideologically burdened. The fear that one will "dwindle into a wife" was memorably articulated by the character Millamant in William Congreve's Restoration comedy The Way of the World. Lisa Ward, a town councilor in Maine, all her life associated the word with helplessness and dependence. "I didn't want to be called a wife—that means somebody takes care of me and I couldn't take care of myself," said Ward, chatting one afternoon in a municipal office down the hall from the clerk who issued her marriage license. "When I was younger, I remember my mother saying: 'I want you to find a good man to take care of you. I know you'll be a great wife.' And I'm like: 'I don't need anybody to take care of me.'" But now she thinks of her wife, Mel Cloutier, as "the person who loves me more than any other person—I don't think of it as the person who has certain duties or responsibilities. My wife is the person I love more than anyone. If I need to take care of her, I will; and if she needs to take care of me, I know she will."