Gender: Why Boys Keep on Trucking
Enlarge Image Getty Images Innate fascination with propulsive motion may explain why boys gravitate to toys that move, like trucks. After watching videos of adults cradling and striking balloons, male but not female 6-to-9-month-olds began to hit balloons more often. This suggests that males have an innate fascination with "propulsive movement," researchers say. After getting acquainted with a toy balloon, 45 children—too young to label themselves by gender—watched split-screen video clips: On one side, a man or woman cradled a balloon; on the other, the same man or woman hit the balloon. Boys tended to watch the people striking balloons more than girls did. After watching, they batted their own balloons more than before, while girls didn't change behavior. There were no sex differences in how children handled the balloons before the videos started and no evidence that the parents of boys had promoted this play style. If an innate fascination with propulsive motion exist...