So we're particularly fond of turning to biology to explain human nature. Take apparent gender differences in how we think and act. Fields like math and science are male-dominated? Well, men must have more natural aptitude for this type of thinking, at least at the high end of the talent distribution. School-aged girls outperform boys when it comes to reading and writing? Probably similar processes at play, just in reverse: the female brain must be better suited for such tasks, right?

Veritable cottage industries have been born by cataloging and explaining gender differences in internal and immutable terms. Men are from Mars and women are from Venus, we're told, in a wide range of pursuits ranging from how we think to what we prefer to how we communicate in relationships.

But isn't this Mars/Venus notion too easy an answer? To depict gender differences in intellectual performance as innate and entrenched is to look right past the other important factors that shape human nature. Take, for example, the extensive body of research on stereotype threat. It demonstrates that even a well-documented gender gap such as that observed for math performance can be eliminated by interventions as small as assuring female students that a test is free of gender bias.

There are compelling explanations for behavior out there that we overlook in our rush to explain each other in internal terms. Sometimes the easy answers for what we observe have nothing to do with biology at all. Sometimes they're as straightforward as video games.

That's right, video games.

Three years ago, Canadian psychologists assessed research participants' spatial abilities using tasks such as mental rotation, in which respondents had to match a geometrical shape to a rotated version of that same shape. Of course, this is a cognitive ability vitally important in fields like math, engineering, and the sciences. And researchers found that, consistent with previous data, men typically outperformed women in the study.

But these researchers did more than record the gender of their college participants. They also assessed other characteristics that they thought might predict spatial aptitude. Like age. Academic major. And, yes, how often they played video games.

The thinking was that the more time respondents spent playing video games, the more practice they'd likely have navigating unfamiliar spaces, manipulating visual objects, and evaluating novel images. Male or female, gaming experience should translate into better spatial performance, and this is exactly what researchers found: students who averaged more than four hours of video games per week outperformed the non-gamers.

What about gender? Well, anyone who has ever been to an arcade can vouch for the fact that there's nothing inherently masculine about video games. Still, young men devote more time to the pursuit than do young women. Just ask the dryer repairman who–in the midst of a recent service call at our house–proudly told me of his decision to tighten his budgetary belt by canceling phone service rather than give up the monthly subscription that allows him to play his Xbox against strangers in Eastern Europe. Perhaps not surprisingly, his girlfriend was less than impressed by his economic recovery plan.

Does this difference in video game exposure help explain the apparent gender gap in spatial skill? The same Canadian research team ran a second study in which they subjected non-gaming participants to four weeks of intensive "video game training." Afterwards, spatial test scores improved across the board, but especially among women. This improvement was long-lasting as well: months later, the positive effects were still evident in students' spatial performance. Just imagine the cumulative effects of an entire childhood devoted to gaming.

Alas, don't get too cocky: your own sordid history of video game consumption need not portend certain academic success or intellectual prowess. Earlier this year, another line of research published in the same scientific journal suggested that video game ownership may very well help explain impaired reading and writing skills among elementary-school-aged boys.

In the study, researchers followed the academic and behavioral functioning of two groups of 1st-3rd grade boys: one given a PlayStation II console with several games, and one that was not. Four months later, boys who had been given a new game system exhibited lower reading and writing test scores, had more teacher-reported academic problems, and engaged in fewer after-school activities. Keep in mind, all this after just four months of video gaming. All your base are belong to us, indeed.

It's tempting to conclude that the behavior of those around us can be explained away in internal, innate, immutable terms. Perhaps particularly so when it comes to gender differences in academic performance. But it turns out that if you really want to address academic gender gaps in extraterrestrial terms, you don't have to stop at Mars and Venus–you might want to look into Space Invaders and Super Mario Galaxy as well.