Birth Order

Once the domain of folk wisdom and old wives' tales, birth order is now being seriously studied by scientists.

The importance of birth order has been known—or at least suspected—for years. But increasingly, there's hard evidence of its impact. In June, for example, a group of Norwegian researchers released a study showing that firstborns are generally smarter than any siblings who come along later, enjoying on average a three-point IQ advantage over the next eldest—probably a result of the intellectual boost that comes from mentoring younger siblings and helping them in day-to-day tasks. The second child, in turn, is a point ahead of the third. While three points might not seem like much, the effect can be enormous. Just 2.3 IQ points can correlate to a 15-point difference in sat scores, which makes an even bigger difference when you're an Ivy League applicant with a 690 verbal score going head to head against someone with a 705. "In many families," says psychologist Frank Sulloway, a visiting scholar at the University of California, Berkeley, and the man who has for decades been seen as the U.S.'s leading authority on birth order, "the firstborn is going to get into Harvard and the second-born isn't."

The differences don't stop there. Studies in the Philippines show that later-born siblings tend to be shorter and weigh less than earlier-borns. (Think the slight advantage the 6-ft. 5-in. [196 cm] Peyton Manning has over the 6-ft. 4-in. [193 cm] Eli doesn't help when he's trying to throw over the outstretched arms of a leaping lineman?) Younger siblings are less likely to be vaccinated than older ones, with last-borns getting immunized sometimes at only half the rate of firstborns. Eldest siblings are also disproportionately represented in high-paying professions. Younger siblings, by contrast, are looser cannons, less educated and less strapping, perhaps, but statistically likelier to live the exhilarating life of an artist or a comedian, an adventurer, entrepreneur, GI or firefighter. And middle children? Well, they can be a puzzle—even to researchers.

I think that as long as people remember that hard and fast rules are hard to come by in social sciences, studies like this are interesting and give parents something to think about when raising their children.

And for the record, I am a first-born. I guess that means I'm guaranteed brains, fame, and fortune.

Yeah, if only.