Scientists have known that purchasing designer handbags and shoes is a means for women to express their style, boost self-esteem, or even signal status.

In a new study, University of Minnesota researchers discovered some women also seek these luxury items to prevent other women from stealing their man.

Researchers used five experiments featuring 649 women of varying ages and relationship statuses to discover how women’s luxury products often function as a signaling system directed at other women who pose a threat to their romantic relationships.

“It might seem irrational that each year Americans spend over $250 billion on women’s luxury products with an average woman acquiring three new handbags a year, but conspicuous consumption is actually smart for women who want to protect their relationship,” says associate professor Vladas Griskevicius.

“When a woman is flaunting designer products, it says to other women ‘back off my man.’”

More here on the research methodology. Perhaps the reason women buy new purses so often is to renew the signal strength, indicating the persistence of both income/status and devotion from the mate. As a guy I have a tough time decoding the price and brands of women's handbags so it seems likely the signal is meant for other women.

It is intriguing to decipher the differing symbols of status among different tribes. On Wall Street it's designer brand suits and wristwatches and street addresses, in Silicon Valley it's Twitter followers, IPO's, and invitations to exclusive conferences.