Study finds elder siblings likely to be more intelligent, ‘tutor’ younger siblings

Psychologists from the University of Mainz and Leipzig University have made an interesting finding that may settle the debate among siblings once and for all. The study, published in the “Proceedings of the National Academy of Sciences,” has found that elder siblings are likely to be more intelligent than their younger sisters and brothers. Findings suggest that the elder siblings’ brains develop quicker as they “tutor” the younger ones growing up together. The widely held belief that last-born children are rebellious, while the first ones are perfectionists, has also been contradicted by the study.

Over 20,000 adults across Britain, the US and Germany were examined for their personality traits, and the data analysed to arrive at the findings. It was found that traits such as agreeableness, conscientiousness, imagination, emotional stability and extraversion were unaffected by the order of birth.

Stefan Schmukle, a co-author of the study, from Leipzig University, said, “This does not only contradict prominent theories of psychology, but also goes against the intuition of many people,” The Independent reports.

It was found that first-borns were more likely to have a richer vocabulary; a minute decline in intelligence among younger siblings was also confirmed. “This effect on intelligence replicates very well in large samples, but it is barely meaningful on the individual level, because it is extremely small,” Schmukle told The Independent. “Even though mean scores on intelligence decline, in four out of 10 cases, the later-born is still smarter than his or her older sibling.”

Julia Rohrer, another author on the study, also from Leipzig University, said, “A firstborn can 'tutor' their younger siblings, explaining how the world works and so on,” reports Health Day. “Teaching other people has high cognitive demands; the children need to recall their own knowledge, structure it and think of a good way to explain it which could be a boost to intelligence for some firstborns.”

Contact the writer at feedback@ibtimes.com.au, or let us know what you think below.