Birth order has little effect on personality
Psychologists from Leipzig and Mainz analyzed central personality traits of over 20,000 grown-ups from Germany, the USA, and Great Britain, and found out that birth order has little effect on personality.
According to commonly-held beliefs, firstborns are supposedly perfectionists, while middle children develop a talent for diplomacy and last-borns are expected to be rebellious.
To shed some light on whether these differences actually exist, Professor Stefan Schmukle and Julia Rohrer of Leipzig University and Professor Boris Egloff of Johannes Gutenberg University Mainz (JGU) analyzed the data of more than 20,000 grown-ups from Germany, the USA, and Great Britain.
They found that central personality traits such as extraversion, emotional stability, agreeableness, and conscientiousness are not affected by birth-order position. Only regarding self-reported intellect small effects were found: Firstborns were more likely to report a rich vocabulary and less difficulty understanding abstract ideas.
These self-reports are not completely unfounded as the study confirmed the already known small decline in objectively measured intelligence from first- to last-born. “This effect on intelligence replicates very well in large samples, but it is barely meaningful on the individual level, because it is extremely small. And even though mean scores on intelligence decline, in four out of ten cases the later-born is still smarter than his or her older sibling,” explained Schnukle. “The real news of our study is that we found no substantial effects of birth order on any of the personality dimensions we examined. This does not only contradict prominent psychological theories, but also goes against the intuition of many people.”
