Almost 50 years ago, Congress passed the Equal Pay Act. It prohibits employers from paying men or women different wages based on gender.
At the time, women earned almost 59 cents for every dollar earned by men, according to the National Committee on Pay Equity.
Earlier this week, the Institute for Women’s Policy Research released a fact sheet finding men make more money than women in almost every occupation. According to the U.S. Bureau of Labor Statistics, women earn 77 cents for every dollar earned by a man.
So how is it that after 50 years, women have only increased their relative pay by 18 cents?
“The fact is that women, in the aggregate, have been shown to value the environment in where they work,” said Dr. Marianne Legato, founder and director of the Partnership for Gender-Specific Medicine at Columbia University. She says these generalizations come from years of brain research.
She said those values include whether the workplace "is supportive and friendly, and relationships with colleagues."
"They are more adept at and interested in teamwork,” Legato added.
Legato has studied brain differences between the sexes for decades, and she said men are more willing to ask for more money when they accept a job.
“Men are extremely competitive. And one of them said to me: 'Money is the report card of life.' I don’t think women see it that way,” Legato said.
Other gender researchers, such as the University of Pennsylvania’s Dr. Reuben Gur, agreed that brain evolution has trained men to be more aggressive, "but this is a very faint biological explanation" for gender differences in pay, "considering that up until not long ago, women were considered property. So, you didn’t have to pay them anything for their work.”
That long legacy of gender discrimination, Legato notes, is important, as it has shaped the evolution of the human brain.
“Every experience that we have,” Legato says, “actually impacts our genetic make-up. Experience modifies the way our genetic material works.”
So when an individual woman is discriminated against, that actually affects her genetic make-up, which in turn could change her behavior to be more docile. Conversely, Legato said, if a woman is encouraged or treated fairly, her behavior could become more responsive and assertive.
Still, while brain science offers a partial explanation of the pay-gap, Gur said it also reveals a level of discrimination in the entire society.
“You can measure how civilized a country is by how close the salary is between males and females,” Gur adds.
If that’s the measurement, American society is exactly 18 cents worth more civilized compared with 1963.