First born children tend to have a higher IQ than their siblings

Question

Is there any truth to this? Would love to piss off my sister

Comments

This claim is true, according to multiple research studies, it is more likely for the first born child to have a slightly higher IQ than the second. Based on an article by Phys.org, “birth order does matter when it comes to IQ.” However, siblings’ IQ differences are determined more by parental strategies than by human biology.  According to the article, much of a child’s enrichment comes down to the way they were raised, and since it is typical for the first born child to receive “undivided attention from the parents,” they are more likely to display higher levels of intelligence.

A piece from the New York Times further supports this claim, stating that the “average difference in IQ was three points higher in the eldest child,” based on a large-scale study. Additionally, the Illinois News Bureau did a study on 377,000 high school students, and found that firstborns did in fact have a higher IQ than their younger siblings. While these differences are small, they do appear to be consistent throughout the majority of research done on first and second born children.

However, some articles stated that the documented differences were insignificant, and that birth order “had no meaningful effect on personality or IQ.” Therefore, while the initial claim is true, the significance of the claim seems to be undermined by other factors, such as upbringing. Since early development is so significant for humans, whatever care they receive as children, or lack-there-of, will give them certain qualities.

The amount of mental stimulation firstborns are given appears to correlate with their intelligence, but that’s not to say a younger sibling couldn’t have a higher intelligence than their older sibling. Overall, the numbers provided from each study are simply averages.

Sources:
https://phys.org/news/2015-10-first-borns-higher-iq-sibling-bonds.html

https://www.nytimes.com/2007/06/22/science/22sibling.html

https://news.illinois.edu/massive-study-birth-order-has-no-meaningful-effect-on-personality-or-iq/

Answer 1

According to this article, there was a study conducted by the University of Edinburgh which observed groups of siblings in the UK. In the study, there is an observed correlation between being the first born sibling and the smartest. This is not due to genetic differences between siblings, but rather a combination of external factors that influence children's intelligence growing up. The study reasons that "mothers take more risks during pregnancy and are less likely to breastfeed and to provide cognitive stimulation for latter-born children," as opposed to the first-born. However, the data shows that these differences in intelligence are slight and not extreme.  

Link to Study: https://jhr.uwpress.org/content/early/2016/11/01/jhr.53.1.0816-8177

Answer 2

According to a study done by the university of Edinburgh, first born siblings are shown to have higher IQs and better thinking skills than their siblings. The study examined "nearly 5,000 children" and found that first-borns scored higher on tests. This is likely because of the "birth order effect"; children born first generally receive a better level of education, and therefore go on to earn more in their careers. Second born children are more likely to look to the older sibling as a role model, while the first born is more likely to look to their parents- a more stable model with a higher IQ. So while first born children may tend to do better in school down the line, they don't seem to be born with a naturally smarter brain.

Source: 

https://jhr.uwpress.org/content/early/2016/11/01/jhr.53.1.0816-8177 

Comments

I like how you provide examples of external factors that correlate to first-borns and education compared to second-born children and how their external factors at home differ. Great work!

Answer 3

According to a NY times article, older siblings are statistically born with a higher IQ than their younger siblings. The average difference between IQ only ranges +3 for the elder siblings. The article also mentions this is due to dynamic family factors not biological factors. 

https://www.nytimes.com/2007/06/21/science/21cnd-sibling.html

Comments

Good jobs providing a reputable source for your fact check. I like that you added information from the source to verify your claim. I think the only improvement that can be made is expanding upon what a dynamic family factor actually is.

Answer 4

There is some truth to this statement. According to the article linked below, there have been various conducted studies done with hundreds of thousands of children that positively confirm that older siblings scored higher on an IQ test, compared to their younger counterparts. The norweigan study performed two iterations of the study: one with 250,000 participants and the other with 100,000 participants. The second study cited that older siblings, on an average, scores 2.3 points higher than their younger siblings.

However, it would be interesting to note that the birth order is not the right term to use but what should be used is the social order. The science literature shows that when comparing siblings that lost an elderly sibling and were treated as if they were the eldest sibling, their scores were about the same as the oldest sibling in a family.

https://www.livescience.com/1651-study-older-siblings-higher-iqs.html

Comments

I like how you cited multiple studies to really bring home your claim!

Answer 5

According to this Live Science article, they mention a study published journal Intelligence, where they looked at 100,000 Norwegian brothers. The older siblings tend to have a higher IQ of 2.3. However, there are other factors that determine this. According to the Winchester Hospital, there are multiple studies that conflict with the claim that birth order affects IQ. There are other factors in play such as parenting, and the environment one grows up in. There is a trend of older siblings having a higher IQ. Whether or not birth order affects one’s IQ is still up for debate. 

https://www.livescience.com/1651-study-older-siblings-higher-iqs.html  

https://www.winchesterhospital.org/health-library/article?id=156997  

Answer 6

To fact-check the claim that first-born children tend to have a higher IQ than their siblings, we can look to scientific research conducted in the field of psychology and child development.

A study published in the journal "From the Cradle to the Labor Market? The Effect of Birth Weight on Adult Outcomes" in 2007 by economists Sandra Black, Paul Devereux, and Kjell Salvanes found that first-born children have, on average, slightly higher IQ scores compared to their younger siblings, but the difference was found to be small (about 1 IQ point) and may not be practically significant.

On the other hand, a more recent study published in "Social Psychological and Personality Science" in 2017 by psychologists Julia M. Rohrer, Boris Egloff, and Stefan C. Schmukle analyzed data from a large national sample and found no significant relationship between birth order and IQ.

Based on the available scientific evidence, the claim that first-born children tend to have higher IQ than their siblings is not supported by strong or consistent evidence. The relationship between birth order and IQ is complex and may be influenced by various factors, and more research is needed to draw definitive conclusions.

Sources: https://psycnet.apa.org/record/2022-52639-004

https://academic.oup.com/qje/article/122/1/409/1924768

Answer 7

Usually, studies have shown that first-born children are smarter than their siblings. A study by the University of Edinburgh shows that first-born kids get more mental stimulation than their brothers and sisters. But there's another study that shows that second-born children, especially boys, are more likely to misbehave sometimes with serious consequences.

I believe that this is more like an opinion among siblings. Research hasn't been consistent, there are different findings about this statement.

You can probably piss your sister off another way.

https://kutv.com/news/nation-world/first-born-children-smarter-than-siblings-second-born-more-likely-to-cause-trouble#:~:text=A%20University%20of%20Edinburgh%20study,than%20their%20brothers%20and%20sisters.

Answer 8

This is exaggerated and misleading. Research has been conducted on this topic and proves this is not a fact. A study done by the proceedings of the National Academy of Sciences, "based on data from 20,000 individuals, concludes that birth order does matter when it comes to IQ"(Wolke). They did find that it is somewhat common for the oldest to have a slightly higher IQ, however this is because of other factors and not always the case. 

Comments

Do you have more information on the study and a source link? Complete fact-checks should cite their source in their explanation and also leave hyperlinks. Thanks!

Answer 9

Correct. According to a science reporter for The New York Times, Benedict Carey, the eldest children in families tend to develop higher I.Q.s than their siblings. According to the study performed, the average difference in I.Q. was slightly three points higher in the eldest child than in the closest sibling but significant. Researchers also said the results made it clear that it was due to family dynamics, not to biological factors like prenatal environment. 

Source: https://www.nytimes.com/2007/06/22/science/22sibling.html?smid=url-share

Comments

Your link doesn't work for me. Does it still open on your end?

---

No, it did not, I hope this one works. https://www.nytimes.com/2007/06/22/science/22sibling.html?smid=url-share

Answer 10

There is some truth to this statement. The article that I have linked below gives good insight on the topic. Typically, the oldest sibling looks up to the parents. The younger sibling looks up to the older sibling. This is one reason that can causes the oldest sibling to have a higher IQ. 

https://kutv.com/news/nation-world/first-born-children-smarter-than-siblings-second-born-more-likely-to-cause-trouble#:~:text=A%20University%20of%20Edinburgh%20study,than%20their%20brothers%20and%20sisters.

Comments

I like that you not only cited reliable information, but also gave a reason on why this is the case.