Studie legt nahe, dass mittlere Kinder kooperativer sind als ihre Geschwister – Nach jahrzehntelanger Debatte legt eine der umfangreichsten Studien aller Zeiten zur Geburtenreihenfolge nahe, dass es tatsächlich einen Unterschied macht.

I’ve linked to the news release in the post above. In this comment, for those interested, here’s the link to the peer reviewed journal article:

https://www.pnas.org/doi/abs/10.1073/pnas.2416709121

Significance

An enduring question in psychology is whether adult personality is related to birth order and number of siblings. Previous studies have generally found no associations except that firstborns average slightly higher than later-borns in intellect-related traits. Our large-sample study supports the findings for intellect-related traits, but unlike previous research, it also shows considerable differences for other traits: On the Honesty-Humility and Agreeableness dimensions, scores were somewhat higher on average for persons having more siblings. Among persons having the same number of siblings, middle-borns and last-borns both averaged slightly higher than firstborns. We discuss the possibility that growing up with more siblings promotes the development of a more cooperative personality.

From the linked article:

Middle children are more cooperative than their siblings, study suggests

After decades of debate, one of largest ever studies on birth order suggests it does actually make a difference

In one of the largest studies ever conducted on birth order, family size and personality, Canadian researchers gathered data from more than 700,000 volunteers and found that on average, middle children scored higher than their siblings on traits seen as important for cooperation.

Scores for the same traits were also higher in families with more children, suggesting that people may be more likely to develop a cooperative personality when they are raised as part of a bigger group.

The effects are not large, but Michael Ashton and Kibeom Lee, psychology professors at Brock University in Ontario and the University of Calgary in Alberta respectively, believe they challenge the idea that birth order and the number of children raised together have no meaningful impact on personality.

“The weight of that evidence now indicates that personality trait levels do differ as a function of birth order and sibship size,” they write in Proceedings of the National Academy of Sciences.

Clearly you’ve never met my brother!

Middle children!? Have you lived or just make up things based on small samples.

guess we’re the exception, im the oldest, my brother in the middle, and my sister was the youngest. my brother was the obstinate one.

Huh, that’s not how it is with my family. Eldest was the most cooperative with the most pressure on them, middle one just kept their head down and did their own thing and youngest made the most noise and demands.

I was a middle child…

Until I wasn’t.

Then my sister was…

Until she wasnt.

Does this mean we stopped being cooperative because our mom got roped into having another one?? How do her choices reflect on us??