MORE than a decade into the 21st century, we would like to think that American parents have similar standards and similar dreams for their sons and daughters. But my study of anonymous, aggregate data from Google searches suggests that contemporary American parents are far more likely to want their boys smart and their girls skinny.

It’s not that parents don’t want their daughters to be bright or their sons to be in shape, but they are much more focused on the braininess of their sons and the waistlines of their daughters.

Start with intelligence. It’s hardly surprising that parents of young children are often excited at the thought that their child may be gifted. In fact, of all Google searches starting “Is my 2-year-old,” the most common next word is “gifted.” But this question is not asked equally about young boys and young girls. Parents are two and a half times more likely to ask “Is my son gifted?” than “Is my daughter gifted?” Parents show a similar bias when using other phrases related to intelligence that they may shy away from saying aloud, like, “Is my son a genius?”

Are parents picking up on legitimate differences between young girls and boys? Perhaps young boys are more likely than young girls to use big words or otherwise show objective signs of giftedness? Nope. If anything, it’s the opposite. At young ages, when parents most often search about possible giftedness, girls have consistently been shown to have larger vocabularies and use more complex sentences. In American schools, girls are 11 percent more likely than boys to be in gifted programs. Despite all this, parents looking around the dinner table appear to see more gifted boys than girls.

Parents were more likely to ask about sons rather than daughters on every matter that I tested related to intelligence, including its absence. There are more searches for “is my son behind” or “stupid” than comparable searches for daughters. Searches with negative words like “stupid” and “behind,” however, are less skewed toward sons than searches with positive words.

What concerns do parents disproportionately have for their daughters? Primarily, anything related to appearance. Consider questions about a child’s weight. Parents Google “Is my daughter overweight?” roughly twice as frequently as they Google “Is my son overweight?” Just as with giftedness, this gender bias is not grounded in reality. About 30 percent of girls are overweight, while 33 percent of boys are. Even though scales measure more overweight boys than girls, parents see — or worry about — overweight girls much more often than overweight boys.

Parents are about twice as likely to ask how to get their daughters to lose weight as they are to ask how to get their sons to do the same. Google search data also tell us that mothers and fathers are more likely to wonder whether their daughter is “beautiful” or “ugly.”

Parents are one and a half times more likely to ask whether their daughter is beautiful than whether their son is, but they are nearly three times more likely to ask whether their daughter is ugly than whether their son is ugly. How Google is expected to know whether a child is beautiful or ugly is hard to say.

In general, parents seem more likely to use positive words in questions about sons. There is a larger bias toward asking whether sons are “tall” than “short.” Parents are more likely to ask whether a son is “happy” and slightly more likely to ask whether a daughter is “depressed.”

Liberal readers may imagine that these biases are more common in conservative parts of the country. Not so. I did not find a significant relationship between any of the biases mentioned and the political or cultural makeup of a state. These biases appear to cut across ideological divisions. In fact, I was unable to find any demographics that significantly reduced the biases. Nor is there evidence that these biases have decreased since 2004, the year for which Google search data is first available.

This methodology can also be used to study gender preference before birth. Every year, Americans make hundreds of thousands of searches asking how to conceive a child of a particular sex. In searches with the words “how to conceive,” Americans are slightly more likely to include the word “boy” than “girl.” Among the subset of Americans Googling for specific gender conception strategies, there is about a 10 percent preference for boys compared with girls.

This boy preference is surprising for two reasons. First, the top websites returned for these queries are overwhelmingly geared toward women, suggesting that women are most often making gender conception searches. Yet in surveys, women express a slight preference for having girls, not boys; men say they prefer sons. Second, many Americans are willing to admit a gender preference to even out a family. About 5 percent more boys are born than girls in the United States, so evening out a family would more often require having a girl, not a boy. Are men searching for conception advice in large numbers? Are women searching on their husbands’ behalf? Or do some American women have a son preference that they are not comfortable admitting to surveys?

Other countries exhibit very large preferences in favor of boys. In India, for each search asking how to conceive a girl, there are three-and-a-half asking how to conceive a boy. With such an overwhelming preference for boys, it is not surprising that there are millions fewer women in India than population scientists would predict.

Clearly there is more to learn. Because this data make it easy to compare different countries over time, for example, we might examine whether these gender preferences change after a woman is elected to run a country.

The disturbing results outlined here leave us with many open questions, but the most poignant may be this one: How would American girls’ lives be different if parents were half as concerned with their bodies and twice as intrigued by their minds?