Birth Order Research

How birth order research can help you select a romantic match

By the time you finish browsing this Web site, you'll be able to predict which of your friends' relationships will be harmonious and which will be troubled. Believe it or not, you'll know more about their compatibility than they do themselves. And you'll be able to see the effects of harmonious and conflicting relationships acted out right in front of your eyes every time you're together with any couple. Knowing about birth order is almost like having psychological X-Ray vision: it lets you see inside relationships and helps you understand how they function to make people happy — or miserable.

Clinical Studies

Research indicates that birth order has a profound impact on personality. In 1996 Frank Sulloway conclusively demonstrated that firstborns are more conscientious and dominant, while lastborns are more agreeable and open to new experience. Other clinical studies reveal that certain birth orders are more compatible. For example, lastborn guys with older sisters report being happier when in relationships with girls who have younger brothers.

Birth order and IQ

Although studies by Norwegian researchers have conclusively shown that firstborns have a higher IQ than laterborns, the difference is small (only about 3 points), and it's important to realize that IQ isn't everything. As Frank Sulloway remarked, if he had the choice between having a few extra IQ points or the "enlarged curiosity" of the typical laterborn, he would "unhesitatingly chose the latter." (NYT, 6/21/2007) (Flyboys photo Copyright © 2006 Metro-Goldwyn-Mayer (MGM).)