A man and his son are driving down the road and they are in a bad car crash. The father dies instantly. The boy is taken to the hospital where he is immediately rushed to surgery, but the surgeon looks down and says, "I can't perform this surgery, he's my son!" If you're asking, “How is this possible?” you'll understand the recent research that explored similar gender assumptions.

If you have heard this story before, you know the answer — the surgeon is the boy's mom. It remains a good example, however, of the kind of unconscious gender bias that can occur in labeling, the focus of a recent study.

The research confirms that parents use gender neutral labels (such as “kid”) more often for boys than for girls. And, they're more likely to use gender-specific labels, such as “girl,” for girls than they do “boy” for boys.

When we perceive the default pronoun to be male, it conveys the assumption females' actions are the exception and can elevate male concerns, priorities and values above those of others.

Distinctions like these may seem picky, but they have far-reaching effects. When we perceive the default pronoun to be male, it conveys the assumption females' actions are the exception. It “has the potential to elevate [male] concerns, priorities, and values above those of others,” Rachel Leshin, the paper's lead author, said in a press release. Because this happens automatically, the implied bias can be difficult to notice.

That means catching the implied assumption of a male actor is a necessary first step in diminishing this bias.

“Understanding the specific factors that may lay foundation for these male defaults is one way to start thinking about how to intervene on this bias,” Leshin, a New York University doctoral student at the time of study and now a postdoctoral research fellow at Princeton University, explained.

In an ingenious series of experiments that included more than 800 parent-child pairs in the United States, Leshin and her colleagues got parents — more than 90 percent of them mothers — to reveal their default modes.

In one experiment, more than 600 parents of children between the ages of four to ten years were shown photographs of individual kids (both boys and girls) playing on a playground. Parents were asked to come up with a caption for the photo and were then told to read it aloud to their children.

The results? Parents were more likely to use gender-neutral labels such as “The kid is sliding” to describe a boy's playground activity. In contrast, parents were more likely to used gender-specific labels such as “This girl is swinging” to describe a girl's activity on the playground.

The team took their research further with another study which included nearly 200 parent-child pairs. During this study, parents participated in a virtual picture-book-reading task designed to encourage an open-ended discussion of gender-related themes.

When we perceive the default pronoun to be male, it conveys the assumption females' actions are the exception.

The picture book depicted characters engaged in distinct gendered behaviors. For instance, digging for worms was done with boy characters, while girl characters engaged in painting their fingernails. In this situation, as before, parents used more gender-neutral labels when discussing the boys who were engaged in their stereotypical behaviors than they did for girls engaged in stereotypical behaviors.

On the other hand, parents used more gender-neutral labels to characterize counter-stereotypical girls compared to counter-stereotypical boys. For example, they identified the girl digging for worms as “kid” more often than they called a boy painting his nails as a “kid.”

The takeaway, Leshin said, is that there is a “notable bias in how parents see gender, signaling that a ‘person,' by default is a male.”

The study is published in PNAS, the Proceedings of the National Academy of Sciences.