Women participate in a Tupperware party in 1948. (CCAD, Smithstonian Institution via AP)

In the past few decades, motherhood has been transformed. A majority of moms now work outside the home; they also spend twice as much time on housework and child care as fathers do. That means mothers are more taxed than ever, and still deeply ambivalent about what their proper role should be. Here are some works that explore this fundamental question:

Mothers and Others,” Sarah Blaffer Hrdy

To really understand motherhood, you have to start at the beginning. That’s what Hrdy, an anthropologist and evolutionary biologist, does in her groundbreaking book. Hrdy challenges the notion of a “maternal instinct.” Using evidence from closely related primate species and modern hunter-gatherer tribes, she shows that men and women are equally wired to nurture and that loving “alloparents” — mothers, fathers, grandparents, siblings, friends — have always cared for and raised our young.

Proverbs 31: 10-31,” the Bible

The notion that a “good mom” should always be busy, selfless and cheerfully obedient is peppered throughout history and culture. But it’s especially well-captured in this exhausting passage about mothers, which reads, in part: “She gets up while it is still night; she provides food for her family. . . . She considers a field and buys it; out of her earnings she plants a vineyard. . . . Her lamp does not go out at night. In her hand she holds the distaff and grasps the spindle with her fingers. . . . She watches over the affairs of her household and does not eat the bread of idleness.”

The Cultural Contradictions of Motherhood,” Sharon Hays

This 1996 book was an instant classic. Hays, a sociologist, shows that the definition of “proper parenting” has always been slightly out of reach, keeping mothers constantly striving and off balance. She chronicles how, for centuries in Europe, child-rearing was a socially devalued task and often outsourced to wet nurses, nannies and boarding schools. That changed with Jean-Jacques Rousseau, who argued for breast-feeding and affectionate mothering, fostering the “cult of true womanhood.”

In Puritan New England, raising children was about guiding their spiritual development, a matter too important to be left to the soft “indulgence” of mothers. Instead, mothers were to follow the rules set by authoritarian fathers. That gave rise to “moral mothering,” urging moms to trust their instincts to bring out a child’s inner goodness; then the 20th century’s “scientific mothering,” which encouraged schedules, letting babies “cry it out” rather than soothing them and emotional distance. That era was followed by “child-centric” mothering, later criticized as “smother mothering.” Then came the benign neglect of the 1960s, followed by the guilt and ambivalence surrounding working mothers, which has culminated, in Hays’s view, in modern “intensive mothering” standards, which have never been higher.

Interview for World’s Toughest Job,” American Greetings

In 2014, the cardmaker released a YouTube video showing interviews for a fake “director of operations” job. It entailed being constantly on your feet, working unlimited hours in chaotic environments (even in the middle of the night), taking no breaks, and being expert in medicine, finance and the culinary arts (among other things). “If you had a life, we’d ask you to sort of give that life up,” the interviewer says. “That’s almost cruel. Almost a very, very sick, twisted joke,” one interviewee says, before the big reveal: Millions of people already do this job, and it’s called being a mother. Cue the music.

The Joy Luck Club,” Amy Tan

There are a host of iconic mother figures in popular culture, from the enraged Medea of ancient Greece and the destructive Hindu mother goddess Kali to “Psycho” Norman Bates’s mother and June Cleaver. But Tan beautifully captures the deep and sometimes fraught relationships between mothers and their children, especially their daughters. And it poignantly shows how little children understand about their parents’ complicated histories and humanity.

The Fatherhood Bonus and the Motherhood Penalty: Parenthood and the Gender Gap in Pay,” Michelle Budig

The upshot: When men become fathers, their pay increases at least 6 percent. Women, on the other hand, experience a 4 percent drop in wages with each child. The penalty is larger for low-wage workers. Similar patterns are found in other countries, and the gap is larger in nations with a more traditional breadwinner-homemaker ideal, such as Germany and Austria.

Changing Rhythms of American Family Life ,” Suzanne Bianchi, Melissa Milkie and John Robinson

In the past few decades, a majority of American mothers went to work outside the home. That was accompanied by deep fears about the negative impact on children. This important book sets the record straight. These sociologists found that working mothers today spend as much time with their children as at-home mothers did in the early 1970s. How? By giving up time for sleep, personal care and adult relationships. Milkie followed up this work with a 2015 study on whether all that additional mothering time had any bearing on child outcomes. While other research shows that quality time with both parents is crucial, Milkie found that the quantity of time had little to no effect on children ages 3 to 18.

Twitter: @BrigidSchulte

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