how do zombies further the gender themes in pride and prejudice and zombies?

The book Pride and Prejudice and Zombies appears, at first glance, to be a very nontraditional novel. However, gender themes within its pages lean toward traditional ideas of femininity and masculinity in many ways.
Since the book is set in the early 1800s, there are still many things that women are not allowed to do. Women are not supposed to work outside the home. They are not supposed to choose their own husbands. Most certainly, they should not be brandishing weapons in battles against zombies. Women are expected to act ladylike at all times . . . but the zombie infestation forces a slight shift in gender norms.
Women are forced to train to kill zombies out of necessity, but this does not automatically make it socially acceptable for a woman to do so. Even as Elizabeth is being trained by her father to fight, her mother is actively seeking an appropriate husband for her. This shows that, even in this time of war, women are still seen as pawns and have little power to decide their own fates.
Men in Pride and Prejudice and Zombies continue to make all of the important decisions, even as women are allowed the "freedom" to learn how to protect themselves and others. It seems that very little has changed, in this book, from the traditional roles of men and women portrayed in other stories set in this era. All that has really changed is the influx of zombies.