SUNDAY, Jan. 15, 2012 (HealthDay News) -- When women seem scarce, men may compete for them by being impulsive, saving less and borrowing more, according to a new study.
"What we see in other animals is that when females are scarce, males become more competitive. They compete more for access to mates," lead author Vladas Griskevicius, an assistant professor of marketing at the Carlson School of Management at the University of Minnesota, said in a university news release.
"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," Griskevicius said.
He and his colleagues conducted a series of experiments with male volunteers and found that they would save 42 percent less and borrow 84 percent more each month if they believed there were more men than women in their local population.
And after looking at photos that included more men than women, men were more likely to take an immediate $20 rather than wait for $30 in a month, according to the study published in the January issue of the Journal of Personality and Social Psychology.
The men in the study were unaware that their perceptions about sex ratios were affecting their behavior, the study authors pointed out.
"Economics tells us that humans make decisions by carefully thinking through our choices; that we're not like animals," Griskevicius said. "It turns out we have a lot in common with other animals. Some of our behaviors are much more reflexive and subconscious. We see that there are more men than women in our environment and it automatically changes our desires, our behaviors and our entire psychology," he added.
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