When led to believe women were scarce, the savings rates for men decreased by a significant 42%. Men were also willing to borrow 84% more money each month.
According to Griskevicius, participants were unaware that sex ratios were having any effect on their behaviour.
“Economics tells us that humans make decisions by carefully thinking through our choices; that we’re not like animals. It turns out we have a lot in common with other animals. Some of our behaviours 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 behaviours, and our entire psychology.”
On the other hand, the study found that sex ratios don’t influence the financial choices women make – but they do shape women’s expectations of how men should spend their money when courting.