Women are more prejudiced toward male strangers when they are fertile, says a new U.S. study, which suggests bias is partly ingrained in human DNA.
Researchers at Michigan State University asked 252 female university students, both Caucasian and black, to look at photos of men's faces, also both Caucasian and black. The women then had to link each face with either a physical adjective, such as muscular, or a mental one, such as brainy.
The women, who were not pregnant nor on hormonal birth control, also recorded their menstrual cycles.
Their study found that fertile women were less accepting of the men they perceived as being muscular if the men were of different race than their own. And because that bias jumped when women were at the peak of their menstrual cycle, when they are most fertile, that prejudice appears to be partly innate, said lead study author Melissa McDonald said.
Existing research indicates fertile women naturally prefer muscular and masculine mates of their own race. But McDonald's team wanted to know how women would react when faced with men of other races, as well.
From an evolutionary standpoint, women don't take their reproductive choices, such as mates and timing, lightly, McDonald said — especially when their window of optimum fertility comes around.
"Compared to men, women have lots of constraints on their ability to produce a lot of offspring. There's nine months of pregnancy and they're generally infertile while they are breastfeeding," said McDonald, a fourth-year PhD student. "So there's a lot of investment."
Therefore, McDonald added, women try to protect themselves from mates who threaten their reproductive choices. She said her team's first study, as well as a second study not based on race, suggests they might do that by being more biased against aggressive or "physical" strange men, including, but not specifically, those of other skin colours.
In the bigger picture, McDonald's work adds to scientists' general understanding of bias and others' efforts to eradicate it.
"A lot of the research in social psychology is focused on biases and prejudice and racism (being) all culturally learned," McDonald said, "and that if we can get rid of these cultural stereotypes, then we can get rid of racial bias."
"(But) this research suggests that at least a small part of our bias against (other groups), including racial groups, is kind of ingrained in our psychology," she said. "So the ways by which we could go about ameliorating this bias are going to have to take that into consideration."
The study appears online in Psychological Science.
lbaziuk@postmedia.com
Cosmopolitan – Mon, 20 Jun, 2011 11:12 AM EDT
