The concept of a “born leader” seems so fanciful and clichéd that it belongs on the cover of a bad business book, or in a quote from a glib cable news commentator. But it turns out that born leaders are real, and researchers have discovered a key variable that isn’t genes, parents, or peers. It’s birth order.

First-born children are 30 percent more likely to be CEOs or politicians, according to a new paper by several economists, Sandra E. Black at the University of Texas-Austin, and Björn Öckert and Erik Grönqvist at Sweden’s Institute for Evaluation of Labour Market and Education Policy. The paper, which only looked at boys, found that first-borns stay in school longer, make more money, have a higher IQ, and even spend more time with homework than television.

The idea that birth order might shape personality goes back at least to the 1920s, when Alfred Adler theorized that first-born children develop a “taste for power” at a young age, since they can dominate their younger siblings and are fixated on avoiding being “dethroned” as the prince of the family. He went on to say that young children are pampered and become dependent on their parents (the “baby of the family” effect), while middle children, coming of age in a war for their parents’ attention, are status-conscious and naturally competitive.

Deriving personality from birth may instinctively strike you—as it has always struck me—as pseudo-Freudian cleverness barely passing for empiricism. But Adler’s hypotheses have held up in numerous studies. In a 2013 paper, “Strategic Parenting, Birth Order and School Performance,” V. Joseph Hotz, a professor of economics at Duke University, and Juan Pantano, a professor of economics at Washington University in St. Louis, used American data to show that school performance declines with birth order.

The researchers chalked their findings up to what they called the “reputational model of strategic parenting.” Put simply, parents invest a lot of time establishing rules for their first child, building a reputation for toughness that they hope will trickle down to later children. As a result, first-borns are doubly blessed—lavished with their parents’ attention, and then entrusted to act as the rules enforcer of the family, which builds intelligence, discipline, and leadership qualities. In surveys, parents report that they consider their older children more successful, and they are less likely to discipline their later-born children for infractions, such as acting up or not doing homework.