There are people who lament that no women now are as funny as Carole Lombard or Barbara Stanwyck in the screwball comedies of Lubitsch, Sturges, and Hawks. They are missing the point: today’s comediennes are on television, where they are often responsible for their own material. Tina Fey, for instance. The former head writer of Saturday Night Live, who wrote the film Mean Girls before creating the sitcom 30 Rock, is one of the leading voices in a new generation of comediennes—women who not only play comic roles but also perform stand-up and write and direct comedy.

Lombard and Stanwyck were great comic actresses on-screen, but they had about as much to do with the joke writing as Jennifer Aniston or Courtney Cox did on Friends. Off-camera Lucille Ball was about as funny as lead. 30 Rock is often compared to The Mary Tyler Moore Show, but James L. Brooks created and wrote that classic sitcom with Allan Burns; Moore and the rest of the cast were talented actors, not comedians. There were always exceptions, sui generis performers such as Mae West and Gracie Allen and Carol Burnett. The difference now is that funny is closer to the norm for women.

“There is no question that there are a million more funny women than there used to be,” says Nora Ephron, the writer and film director. “But everything has more women. There are more women in a whole bunch of places, and this is one of them.” Ephron knows exactly why female comedians are currently much more successful than they used to be. “Here’s the answer to any question: cable,” she says. “There are so many hours to fill, and they ran out of men, so then there were women.”

The humor of women has been a sensitive topic ever since the first one cracked a joke. (In Genesis, Sarah, pregnant long past her childbearing years, says her son is named Isaac, Hebrew for “laughter,” because it’s funny she would have a child at her age.) Throughout time, prominent, deeply serious men have argued that women have no sense of humor. Shakespeare didn’t agree, and the 19th-century English novelist George Meredith suggested that without the tempering wit of women there could be no real comedy at all. His examples were the Middle East and Germany. (“The German literary laugh, like the timed awakenings of their Barbarossa in the hollows of the Untersberg, is infrequent, and rather monstrous,” Meredith wrote, “never a laugh of men and women in concert.”)

But the suffragette movement must have taken a toll on the male ego: by the late 19th century the humorlessness of women was a staple of club toasts and magazines such as Punch. Jerry Lewis picked it up again in earnest in 2000, telling an audience at a comedy festival, “I don’t like any female comedians.” When Martin Short, also onstage, said that he surely must have liked Lucille Ball, Lewis flatly replied, “No.” (Lewis later softened his assessment on Larry King Live but not by much.)