A growing consensus among economists and sociologists about the pay gap between men and women has even The New York Times acknowledging sexism might not be the primary cause.

Evidence is backing up what has been apparent for some time to those willing to consider causes for the gap other than sexist policies driven by the so-called patriarchy — women, especially mothers, are choosing to work fewer hours. NYT correspondent Claire Cain Miller highlighted this fact in an in-depth piece on a shift in the American economy that is disproportionately rewarding those who work long, inflexible hours. Many mothers, it turns out, are choosing to stay home more as a result.

“There are many causes of the gap, like discrimination and a lack of family-friendly policies,” she writes. “But recently, mounting evidence has led economists and sociologists to converge on a major driver — one that ostensibly has nothing to do with gender.” (RELATED: Gender Wage Gap Is Due To Men Working Longer Hours)

The story centers on a couple who chose to divide the labor, so that the mother works part-time in order to focus on raising their children, while the father works 60- to 80-hour weeks at a law firm. Her choice to set aside her full-time job allows him the ability to work inflexible hours now, which in turn will lead to long term financial gains for their family.

Miller is quick to point out that women like this mother aren’t opting out of work altogether, but the fact remains that they are making a choice to focus on their family at the expense of work hours. “For the most part, women who work extreme hours get paid as much as men who do,” Miller writes. “But far fewer women do it, particularly mothers.”

While Miller’s report casts all this in a negative light, because of the choices the changes to the economy are forcing some women to make. But it’s also an example of one of the positive benefits of traditional divisions of labor in marriage. The woman sacrifices work hours, but in return the entire family prospers in the long run.

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