I’m fascinated by the things science knows but doesn’t know why.
Take the study covered in this article from today’s New York Times about girls developing breasts as early as age 7 or 8. It recalls a rabble-rousing paper published in Pediatrics in 1997 that found signs of puberty in girls of that age were far more common than reported.
We’re told in the second graf about the “concern and heated debate” over whether girls are reaching puberty earlier (the headline writer [“First Signs of Puberty Seen in Younger Girls”] thinks they are) and why.
We’re told further down that we don't even know if there’s “an ideal age when girls should reach puberty” and, if there is, no one knows it.
And there appears to be a racial component to the newest study—news that the white study participants (possibly overweight ones, if I’m reading between the lines correctly) “clearly” are entering puberty earlier than expected—other studies have found that “black and Hispanic girls mature earlier than whites” but again—you guessed it—“[n]o one knows why.”
In fact, ignoring instances of the word “can” used instead of “does” or “is,” the author worked well to not repeat her weasel words and phrases (which, don't get me wrong, are necessary here). I count one each of “are thought,” “suspect,” “unproved,” “cautioned,” “probably,” “might,” “was possible” and “somewhat,” two counts each of “suggest” and “no one knows” and three instances of “may be/have.”
What do we know for sure about the age of puberty? It initially dropped because people ate better and we got some control over infectious disease. Why may it be dropping still? Who knows.