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>> RELATIONSHIPS

Love Is in the AirRomantic music boosts men’s chances with the ladies

The surest way to a woman’s heart may be through her ears. In a study published in the July issue of Psychology of Music, researchers at the University of Southern Brittany in France exposed single 18- to 20-year-old women to either music with romantic lyrics or neutral lyrics while they waited to complete a taste test with a 20-year-old male research assistant posing as another student volun-teer. During a break, the male confederate asked the female participants for their phone number. Fifty-two percent of the women who heard romantic music said yes compared with only 28 percent who heard neutral music—something to think about next time you’re playing the jukebox. —Ferris Jabr

>> CHILD DEVELOPMENT

Babies on the EdgeWhen they learn to walk, toddlers must � gure out their limitations all over again

Mountain goats are born understanding where they should and shouldn’t climb, but baby humans need practice puttering around before they can make sound judgments. Now New York University developmental psychol-ogist Karen Adolph has found that for each new phase of motor development, infants have to relearn how to keep themselves safe.

Adolph tested how infants judge risk by setting 12- and 18-month-old infants at the top of an adjustable wooden “cliff” and having their mothers beckon them over the edge. (Lab staff guarded the babies closely and caught any who actually tumbled off.)

Babies who had been crawling for months generally did not go over drop-offs that were too big for them, nor did babies who had been walking for a while. But many babies who had just started walking marched straight over drop-offs beyond their capabilities—even the highest, most obvious three-foot plunge.

What that means, Adolph explains, is that crawling infants do not learn to be afraid of heights. Instead they learn what their crawling bodies can do, and when their style of locomotion changes, they need practice to recalibrate how they perceive their abilities.

Adults adjust to changing motor limitations every day: they may shift their body weight to ease up on a sore leg or take smaller, more deliberate steps when there is ice on the ground. Adolph says we learn that adaptability as infants by experimenting with physical limits and making mistakes.

For parents, of course, there’s another lesson in the research: unless your kids are mountain goats, keep a watchful eye on them when they start to walk. —Mara Grunbaum

It’s no surprise that humans dislike greediness. But a study in the August issue of the Journal of Personality and Social Psychology found that peo-ple sometimes punish generosity, too. The subjects played a computer game where opponents put points (worth money) into a common pot. Afterward, subjects often voted to kick out of the group computer-con-trolled players who put in more points and took less than the others. Per-haps people recoiled because the overgivers violated social norms—rules are rules, even if breaking them bene� ts everyone—or because they set high standards that players are reluctant to measure up to. Because of our natural aversion to inequality, the study authors say, we sometimes � nd generosity as annoying as sel� shness. —Valerie Ross

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! >> FAIRNESS

That’s Nice, Now Get OutGenerosity is sometimes unwelcome

MiQ610News3p.indd 7 9/13/10 7:02:10 PM