Why firstborn kids are more likely to become CEOs

Why are some people more successful in their careers than others?

As it turns out, our fates may be sealed long before we enter the workforce. A new study finds that birth order plays a big role in determining who makes it to the corner office.

The study by Sandra Black, an economist and visiting fellow at the Brookings Institution, contends that firstborn children are more likely than their siblings to eventually rise to become CEOs, government officials and others in high-ranking positions. Black collaborated on the study with Erik Gronqvist and Bjorn Ockert of Sweden’s Institute for Evaluation of Labour Market and Education Policy.

The trio analyzed Swedish government data on a half-million men born between 1952 and 1982. Among other things, they examined the results of psychological and intellectual tests administered by the government before the men began their mandatory military service around the age of 18. (Sweden ended compulsory military service for men in 2010, although the country soon plans to reintroduce it in response to global security challenges.)

Black and her colleagues discovered that firstborn kids (in this case strictly men) were more likely than those with older siblings to have certain personality traits that breed career success, at least by traditional measures. Firstborn kids tend to grow up to be emotionally stable, persistent, outgoing and willing to take responsibility and initiative, according to the study.

Black has studied the effects of birth order in the past and come up with similar findings. In previous research, she analyzed data from Norway and discovered that, even within the same family, firstborn children tend to outshine their younger siblings when it comes to educational attainment, earnings, intellectual prowess (as measured by IQ) and health outcomes.

Her latest study, which also analyzed occupational data, found that the personality differences between firstborns and their siblings have an influence over their career paths. Firstborn children are much more likely than their siblings to become managers. Meanwhile, later-born kids are more likely to be self-employed as adults.

What’s more, firstborns are more likely to hold jobs that require strong social and leadership skills as well as conscientiousness, agreeableness, emotional stability and extraversion. Such jobs include chief executive officers, legislators and senior government officials.

While the study focused on men, Black and colleagues found similar patterns for women when they analyzed occupational data.

Interestingly, the effects of birth order are influenced by gender differences among siblings. For instance, a boy with an older brother is even less likely to possess certain career-enhancing personality traits than a boy with older sisters. And boys with older brothers are more likely to enter creative fields, such as writing and music, than boys with older sisters, according to the study.

Why does birth order seem to make such a big difference? In the age-old debate over nature versus nurture, nurture rules the day here. In other words, first-born kids tend to have certain traits because of their experiences growing up, rather than because of physiological differences tied to birth order, according to Black.

To test to role of biology on personality differences by birth order, Black and her colleagues studied a subsample of families in which biological birth order is different than social birth order, owing to the death of a child or an adoption. In the end, they concluded that the “birth order effect” is driven entirely by “environmental factors,” or experiential differences among siblings.

As teenagers, firstborn kids are more likely to spend time reading books and doing homework than their siblings are as teens. Firstborns also spend less time watching TV or playing video games.

While most parents try not to favor one child over another, the reality is that many fall short of that goal. According to the study, parents tend to spend less time discussing school work with their youngest children than they do with their older kids -- which suggests that, despite their best intentions, many parents invest more of their time in their firstborns.

Black said her study is intended to shed light on factors that influence outcomes for children. “We are chipping away at understanding what determines children’s outcomes and how it relates to family and environment,” said Black.

She added: “There’s something about birth order that really matters on a whole bunch of different dimensions.”