It's important to know that physiological changes are affecting America's kids. But it's just as important to realize that cultural and moral changes are affecting them ever more.

       Researchers have documented what many parents understand instinctively: Today's eleven to thirteen-year-old girls are very different from their grandmothers, and one of the ways they're different is physiological. The average age for the onset of puberty has dropped from seventeen years old in the middle nineteenth century to a little more than twelve years old today.

       There's other evidence, as well. Put delicately, today's twelve-year-olds increasingly look like yesterday's sixteen and seventeen-year-olds. TIME interviewed one twelve-year-old who had been mistaken for a seventeen-year-old, and had been asked by boys whether she had had plastic surgery. Another girl compared boys' reaction to those of "dogs... who won't go away."

       But at least one person thinks that there may be more going on than what our daughters eat. Dr. Drew Pinsky, who used to host a show on MTV, told TIME that constant exposure to sexual images in videos, music, and advertising is having a physical, as well as psychological, effect on our daughters. As he put it, "MTV is absolutely one of the factors in earlier puberty."

       Whether Pinsky's theory is right or not, he puts his finger on the real concern: the over sexualized culture our daughters are growing up in. TIME inadvertently underscores this fact. It tells readers that the two young girls featured in the article, "the attention is such a source of pride that [they] were willing to use their real names."

       There you have it. Not a hint of modesty. Not a hint of discomfort at being followed around by boys who "like dogs... won't go away" or being treated like sexual objects.

       It isn't too much to say that the real problem isn't what's happening to our daughters' bodies-as serious as that may be. Rather, it's what our culture is inclining them to do with their bodies. That's what has parents worried.

       If American culture could again respect modesty and pay heed to protecting our children's innocence, earlier physical maturation wouldn't seem so threatening. But, instead, we're left wondering whether nature and nurture may not combine before long to render childhood extinct.

       Well, we may not be able to shape the physiology of our daughters, but there's a lot we can do about their nurture. As parents, we have to be willing to protect our kids from the assault on their innocence-no matter how much they may complain or tell us about what other parents do. Parents are the first line of defense.

       In our communities, we must be willing to risk a little bit of ridicule to speak out against the sexually charged materials being aimed at our kids. And we can hope and pray that President Bush will keep his promise to crack down on Hollywood sleaze.

       If we're willing to pay the price, nature doesn't have to have the last word. But if we're not, we'll have a lot more to worry about than just our daughters' outward appearances.