Nature vs. nurture - Twins separated - IQ diff

[packman]

A pair of identical twins who were raised in separate countries have displayed unexpectedly large disparities in cognitive abilities while exhibiting highly similar personality traits. A comparison of the monozygotic sibling’s characteristics sheds new light on the age-old nature/nurture debate.

Born in Seoul, South Korea, in 1974, the sisters became separated at the age of two when one twin got lost at a market. Despite her parents’ appearance on a television program about missing persons, the young girl could not be reunited with her family and ended up being adopted by a couple in the US.

Growing up stateside, the adopted twin was unaware that she even had any siblings until she submitted her DNA to South Korea’s program for reuniting family members in 2018. Two years later, she received word that she not only had an identical twin, but an older brother and sister too.

Having been reunited, the twins then completed a series of tests designed to assess their intelligence, personality profiles, mental health, and medical history. Somewhat surprisingly, results revealed that the IQ of the twin raised in the US was 16 points lower than that of the Korean-raised sibling.

https://www.iflscience.com/identical-twins-raised-separately-in-the-us-and-korea-have-massive-iq-difference-66779

[marybourg]

1. They don't look identical to me.

Ears, eyebrows.

[WhiskeyGrinder]

2. Those aren't the kids in the story.

[marybourg]

14. Ahhh.

[Hugh_Lebowski]

5. I would bet money those are monozygotic twins in the picture

Identical is a bit of a misnomer. They start that way, they don't stay that way, not even if you only consider physical appearance.

My SIL (at the time) had monozygotic twins 8 years ago, and while as babies I couldn't tell them apart, I definitely could be the time they were 2 yo.

[Ms. Toad]

8. There was a pair of identical twins in the high school I taught at.

No one could tell them apart except the math teachers. So they would regularly switch classes for the day, but they knew that whenever they arrived in math class they would hear, "D'Andre go back to whatever class you're supposed to be in and send D'Angelo here (or vice versa).

[shrike3]

15. I have known a couple of pairs of identical twins

I could always tell them apart, especially once I got to know them. There were subtle differences. Particularly in the shape of the face. But then, I'm sure I never met the twins you knew, so who knows?

[Ms. Toad]

16. I'm not sure why it was only the math teachers - and all of the math teachers

who could distinguish them. But they commented on it when we caught them, as did the other teachers who wanted to know how we did it.

[wnylib]

20. I have identical twin 2nd cousins.

I could never tell them apart but their siblings never had a problem with it. I only saw them a couple times a year at holidays. Their siblings spent every day with them.

[shrike3]

25. That's pretty awesome they could fool most of the teachers.

I'd take advantage of that if I were a twin.

I remember being home sick and watching "Days of Our Lives," remember that one? One of the actresses had an identical twin in real life, and the twin played her twin on the show. Only thing was, you could tell them apart. They were adults. It was pretty obvious. And they had this plotline where people were getting them confused; it was unintentionally hilarious.

[Ms. Toad]

26. As I recall, they were both very intelligent and charming.

They were just having a lot of fun with it, rather than taking advantage of it for any sort of gain. I wish I could remember their last names - I'd love to find out what they are up to by now. I think they'd be around 50 by now.

I remember the soap opera, but I don't think it was one of the ones I occasionally watched.

[Hugh_Lebowski]

3. I think 'intelligence' is too nebulous of concept in the first place

And different people designing tests have different ideas about what it is constituted of. It's possible in an IQ test designed by a different group, the other child may've scored equal or higher.

I also think it's virtually impossible to devise an 'intelligence' test that is not, at least in subtle ways, linked to the quality of education received by the individual up to that point, and therefore also the degree to which parents encourage/influence said education will impact test scores as well.

Interactions with parents and others in the early stages of life (0-5 especially) play a role in intellectual development as well. These twins were separated at around 2 years of age.

To me there's not much surprising about the fact that the one raised by their biological parents in S. Korea would outscore their US-raised sibling, that one being raised by adoptive parents.

Regardless, it is very interesting research!

[stopdiggin]

9. +1. Interesting, but I'm not sure if this says

much of anything about either intelligence (the devil is in the measurement) - or perhaps even the nature/nurture debate. (who, exactly, is arguing a pure either/or for this equation?)

[WhiskeyGrinder]

4. It's well known that trauma affects cognitive abilities.

And IQ is an outdated, racist, classist concept. What a heartbreaking story this is.

[vanlassie]

6. That poor child probably shut down for a long time, during an

Extremely formative time in her development. No surprise. Surprise would be if she didn’t sustain permanent deficits.

[wnylib]

21. Agree. The trauma for a child that age losing

her family and familiar surroundings at a time when she could not articulate her feelings must surely have affected her development.

[Victor_c3]

22. The article did say that the US raised sibling suffered three concussions

And the article noted these head injuries could lead to the difference.

…. Just to further muddy up the conclusions being made

[Ms. Toad]

7. That appears to be a standard shutterstock image,

Rather than one of this pair of twins.

[Hortensis]

10. Those highly similar personality traits include political orientation.

From Pew:

"Using data collected from a large sample of fraternal and identical twins, a research team found that genes likely explain as much as half of why people are liberal or conservative, see the world as a dangerous place, hold egalitarian values, or embrace hard-core authoritarian views.

Individual experiences and other social influences explain much of the remaining variation in political attitudes, ..."

https://www.pewresearch.org/fact-tank/2013/12/09/study-on-twins-suggests-our-political-beliefs-may-be-hard-wired/

[Hortensis]

11. South Korea's known for high educational standards.

The U.S. is also, but we also know education quality can vary a great deal in this much larger, much more culturally diverse nation.

[JanMichael]

12. I couldn't access the full article. But my guess is the one in Korea stayed put

The child in the United States probably change school districts and schools more often k-12 because of the divorce of the adoptive parents.

First off disabuse the idea of military schools and everything is cool with moving a lot.

A landmark Dutch study of over 50 years of student movement showed that the school moves did have a negative impact. 0 to 3 not so bad. 4 to 10 starts getting worse with bad behavior suicide criminal activity and so on as the number goes up.

If I'm right and the divorce caused multiple school moves, some mid-year as well, and the one in Korea stayed pretty much in the same house k through 12, that alone would explain it.

[niyad]

17. Hmmm. As a military dependent, I went to 7 schools in 9 years in 4 states,

due to my father's transfers. Apart from being a radical feminist, not so much as a parking ticket, no drugs, etc. And that is with genetic alcoholism and clinical depression in the family lines.

Perhaps I am an outlier. Or an ET.

[JanMichael]

18. Probably just the same as I am except we weren't military.

And I am talking about the data not outliers.

Specifically I was talking about the DOD schools. While not everybody in the military sends their kids there they are good schools with transient students but long-term teachers and standard curriculum.

http://breakingground.wamu.org/department-of-defense-schools/index.html

The military school system is not the same as having divorced parents and moving all the time like I did as a kid to places where there was no community there was no anything other than you're new. Most youth school moves are not because of parent job promotion they are from household dissolution.

https://www.researchgate.net/publication/258123993_Moving_Schools_Antecedents_Impact_on_Students_and_Interventions

I can't find the 50 year study from, I think, the Netherlands. It tracked everyone because of their national programs. Basically

I went to five elementary schools two junior highs and three high schools in three states and five cities. It did hurt me academically specifically in math and English. Mainly because of the two mid-year moves in don't different states.

All that said it would be nice to know the history of the twins.

[Baitball Blogger]

13. Hmmm. The one with the lower IQ had three concussions.

So, yeah, more study is needed.

[Victor_c3]

23. +1 n/t

[roamer65]

27. That definitely could make a difference.

CTE.

[Buckeyeblue]

19. Isn't it typical for 1 twin to be smarter than the other?

And also for them to have different personalities and different physical capabilities. One twin could be gay and the other straight. I could go on. I think most capabilities come from a mixture of genetics and environment.

[Zeitghost]

24. I agree with those who brought up the trauma issue

Being separated from your family at two and going through the orphan/adoption process had to have effects on the child's development.

[ecstatic]

28. Yikes.

Between the trauma of being lost as a baby, adopted, sent to another country, three concussions, divorce and several moves, there are too many other factors at play here. Although, it does seem to be common sense that a different environment affects how one's intelligence is developed/expressed. Use it or lose it, perhaps?