Miscalibrated Minds: Why Don’t We Apply What We Know About Twins to Everybody? • Hacker News Board

Re: Miscalibrated Minds: Why Don’t We Apply What We Know About Twins to Everybody?

#21

Post by pbhjpbhj » Thu, Oct 01, 2009, 2:03 PM UTC

latortuga wrote: post #9

As I'm about half done with Good Calories, Bad Calories, this post rather resonates. My mother is an identical twin and she is about as equal in stature to her sister as you can be. It's curious to me that I've always accepted that since they're twins, they must have similar body types. It is very quickly apparent to me that, because they live apart and don't eat the same things, weight and/or body type must have som…

Are you sure they don't eat the same things? They grew up together? This is most likely to mean that they eat a similar diet - if they co-habit with people outside the others social setting then that's probably going to lead away from similar diets.

My cooking is very much influenced by the things my mother cooked for me; I also borrow recipes from my sister occasionally.

Re: Miscalibrated Minds: Why Don’t We Apply What We Know About Twins to Everybody?

#22

Post by xiaoma » Thu, Oct 01, 2009, 2:15 PM UTC

berntb wrote: post #17

JCThoughtscream wrote: post #2

I'd contest the statement that "nobody’s surprised when identical twins turn out to have very similar bodies (weight, muscle mass, etc), even into adulthood." From the research I remember reading about, there does seem to be some genuine level of surprise as to how much influence genetics has over even twins separated at or near birth - and that the level of genetic determinism that twins exhibit is certainly rather…

Twins also shares a common pre-birth environment, with the same environmental influences. I've read the argument that probably helps a lot to make them similar.

Actually, those identical who grow up apart (in the same country) are more similar to each other than those who grow up together.

Also, there's quite a bit of research comparing monozygotic (i.e. "identical") and dizygotic twins. The differences in correlation are stark. Twins who share the same genes are far, far more alike than those who don't: http://en.wikipedia.org/wiki/File:Heritability-from-twin-cor...

Re: Miscalibrated Minds: Why Don’t We Apply What We Know About Twins to Everybody?

#23

Post by xiaoma » Thu, Oct 01, 2009, 2:19 PM UTC

pbhjpbhj wrote: post #20

ZeroGravitas wrote: post #19

Earlier quoted context omitted.

From the other story: "For a start I was 15kg heavier than my brother." but... "Of the thousands of twins enrolled in the research program only 10 were more different in weight than us." So it seems that in general twins weigh roughly the same.

15kg is quite a lot. Most men in my street (by sight) would be within 15kg of me, I'm about 83kg ~ 13 stone (slightly over WolframAlpha's reported median USA male weight in 2006). I think the chance of being more than 15kg outside the weight of someone who has grown up in the same lifestyle and with the same food opportunity is probably pretty low.

When I went back to the states, I saw people that weighed 50kg more than others near them pretty much every time I went out.

Re: Miscalibrated Minds: Why Don’t We Apply What We Know About Twins to Everybody?

#24

Post by Tichy » Thu, Oct 01, 2009, 5:42 PM UTC

ZeroGravitas wrote: post #19

Tichy wrote: post #12

Only yesterday there was another submission about a twin who weighs 15 pounds (or kg?) more than his brother. Really, what DO we know about twins? Most twins also grow up in the same environment and with the same education. In fact when I looked up some IQ studies of twins, it turns out that there really aren't many cases of twins that have not grown up together. Usually some war happenings were the background. As a…

From the other story: "For a start I was 15kg heavier than my brother." but... "Of the thousands of twins enrolled in the research program only 10 were more different in weight than us." So it seems that in general twins weigh roughly the same.

"So it seems that in general twins weigh roughly the same."

It should be easy to study the eating habits of these twins. In most cases, why should they differ much, if they have been raised in the same household?

Re: Miscalibrated Minds: Why Don’t We Apply What We Know About Twins to Everybody?

#25

Post by berntb » Fri, Oct 02, 2009, 1:07 AM UTC

xiaoma wrote: post #22

berntb wrote: post #17

Earlier quoted context omitted.

Twins also shares a common pre-birth environment, with the same environmental influences. I've read the argument that probably helps a lot to make them similar.

Actually, those identical who grow up apart (in the same country) are more similar to each other than those who grow up together. Also, there's quite a bit of research comparing monozygotic (i.e. "identical") and dizygotic twins. The differences in correlation are stark. Twins who share the same genes are far, far more alike than those who don't: http://en.wikipedia.org/wiki/File:Heritability-from-twin-cor...

>>Actually, those identical who grow up apart (in the same country) are more similar to each other than those who grow up together.

Not relevant. I noted that the environment in the womb was very similar for twins, which certainly influences a lot.

(It was a nitpicking note, I am aware of the strength of the twin arguments in general and not one of those idealists which dislikes arguments which goes against Marx -- or whatever it now is that the twin arguments contradict...)