Men prompted to believe that women are scarce are more willing to open their wallets, according to new research on competition in the dating world.
A dearth of men doesn't make women spendthrifts, but believing men are plentiful does trigger women to believe men should be spending more on them, the study found. While the research was done in a laboratory setting, there is some real-world evidence that cities with higher ratios of men also have higher levels of debt. The wild animal kingdom is rife with such competitive behavior.
"What we see in other animals is that when females are scarce, males become more competitive. They compete more for access to mates," said study researcher Vladas Griskevicius, a professor of marketing at the University of Minnesota. "How do humans compete for access to mates? What you find across cultures is that men often do it through money, through status and through products."
The study participants read news articles that described their local populations being either male- or female-skewed. Next, they were asked to report how much money they would save each month from a given paycheck, as well as how much credit card debt they would take on. When led to believe women were scare, men decreased their savings rate by 42 percent and indicated they were willing to borrow 84 percent more each month. (Past research has shown that scarcity of the female kind led to more commitment by men.)
In a second study, participants looked at a series of pictures that either had more men, more women, or equal gender ratios. Afterward, the participants chose between receiving a small amount of money immediately versus a larger amount in a month. When women were scarce in the photos, men were more likely to take $20 right away rather than $30 later.
"We see that there are more men than women in our environment, and it automatically changes our desires, our behaviors and our entire psychology," Griskevicius said.
The cost of love
Women weren't affected like men, but when they read that their area was populated with more men than women, they expected men to spend more on courting-related expenses such as dinner dates and engagement rings.
"When there's a scarcity of women, women felt men should go out of their way to court them," Griskevicius said. Men agreed, apparently: When made to think men outnumbered the ladies, they also reported that they would spend higher amounts on romantic conquests.
An analysis of 120 U.S. cities provided some tantalizing real-world backup for the results found in the lab. Communities with a population skewed toward men had higher debt levels and greater ownership of credit cards. For example, in Columbus, Ga., where there are 1.18 single men for every single woman, the average consumer debt was $3,479 higher than in Macon, Ga., less than 100 miles away but with 0.78 single men for every woman.
The researchers report their results in January in the Journal of Personality and Social Psychology.
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.