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Prenatal testosterone linked to long-term effects in females with male twin

phys.org

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Re: Prenatal testosterone linked to long-term effects in females with male twin

#41

Post by msviss »

jessaustin wrote: post #37
duado wrote: post #32

Earlier quoted context omitted.

No, I’m American and found it one of the funniest comments I’ve read in a while.

It is so nice to come on HN and get some relief from the monotonous humorlessness that is life in USA today. For a moment, I imagine that I can laugh at funny statements no matter which way they point politically, rather than restricting my entertainment to grumbling in approved ways about whomever we're supposed to despise now.

You know I can’t figure out if your sarcastic or not?

Either way, funny!

Re: Prenatal testosterone linked to long-term effects in females with male twin

#42

Post by olau »

tofof wrote: post #24
burger_moon wrote: post #10

My girlfriend has a twin brother. Since they were born in Haiti and we live in the US I'm not sure how relevant this study would be towards her, meaning the socioeconomic changes between living in those two countries is pretty wide. How does prenatal test affect someone after they've gone through puberty? I just don't see how that can be attributed towards college graduation or marriage rates. Is that not a far reach…

> How does prenatal test affect someone after they've gone through puberty The test doesn't affect them. Hormone levels during development are the primary way the body controls development, so even small alterations in hormone levels in utero would be expected to have large physiological consequences. > Is that not a far reaching statement to associate the two Luckily, the field of statistics gives us ways to reason…

> Luckily, the field of statistics gives us ways to reason about whether or not to believe an observed effect.

What you mean is correlation, right? Effect would imply causation.

Re: Prenatal testosterone linked to long-term effects in females with male twin

#43

Post by alwaysanagenda »

Has nobody recognized that not a single biologist, chemist, neurosurgeon, hormone specialist, neo-natal specialist, or just general medical doctor participated or helped produce this study?

Here are the authors:

Aline Bütikofer - Department of Economics, Norwegian School of Economics, 5045 Bergen, Norway David N. Figlio - School of Education and Social Policy, Northwestern University, Evanston, IL 60208 Krzysztof Karbownik - Institute for Policy Research, Northwestern University, Evanston, IL 60208 Christopher W. Kuzawa - Department of Economics, Emory University, Atlanta, GA 30322 Kjell G. Salvanes - Department of Anthropology, Northwestern University, Evanston, IL 60208

So we have, two economists, one anthropologist, and two people who specialize in "social policy."

They did not work with these twins, they did not do their own medical research and assessment. They literally "[used] data on all births in Norway (n = 728,842, including 13,800 twins) between 1967 and 1978 to show that females exposed in utero to a male co-twin have a decreased probability of..."

This is not meaningful research.

This is playing with statistics and cherry picking existing scientific literature to produce a headline that propels an agenda.

This is propaganda of the highest order.

Re: Prenatal testosterone linked to long-term effects in females with male twin

#44

Post by tofof »

alwaysanagenda wrote: post #43

Has nobody recognized that not a single biologist, chemist, neurosurgeon, hormone specialist, neo-natal specialist, or just general medical doctor participated or helped produce this study? Here are the authors: Aline Bütikofer - Department of Economics, Norwegian School of Economics, 5045 Bergen, Norway David N. Figlio - School of Education and Social Policy, Northwestern University, Evanston, IL 60208 Krzysztof Kar…

Why do you suggest fields other than anthropology or economics should be the qualification for analyzing population-level economic effects?

Are you aware that the vast majority of scientific research is done by PhDs, not MDs? And that both are doctorates?

> ... propels an agenda. This is propaganda of the highest order.

What's the agenda? And did that agenda apply to the 2011 paper calling for more research in this area - "Evaluating the twin testosterone transfer hypothesis: a review of the empirical evidence"[1]?

Was that agenda behind this 2012 Japanese study[2] which examined the ratio of middle finger to pinky finger in twins? It's the same hormone transfer hypothesis being examined. What propaganda could there possibly be about the lengths of one's fingers?

Was that agenda present in 1993? [3]

Does that agenda include propoganda about females becoming better at 3d-spatial mental manipulation tasks? [4] If so, why?

Is propaganda about mouse behaviors part of that agenda? [5] If not, why not? Still that same hormone transfer hypothesis being discussed.

Perhaps this 1988 paper on intrauterine position of gerbil fetuses [6] and resulting variance in hormonal exposure from siblings was the birth of this propaganda agenda?

Or is it more sinister than that, and this agenda extends all the way back to 1959 [7], causing these doctors to 'play with statistics' instead of doing what they said - applying testosterone in-utero and watching for behavioral changes? And then I suppose Dr Phoenix would do more 'playing' in 1967 [8] instead of actually measuring testosterone uptake rates of the various tissues he avoided actually manipulating eight years prior...

1: https://www.ncbi.nlm.nih.gov/pubmed/21893061

2: https://www.ncbi.nlm.nih.gov/pubmed/22270254

3: https://www.ncbi.nlm.nih.gov/pubmed/8240211

4: https://www.ncbi.nlm.nih.gov/pubmed/21094200

5: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3212613/

6: https://www.ncbi.nlm.nih.gov/pubmed/3387473

7: https://www.ncbi.nlm.nih.gov/pubmed/14432658

8: https://www.ncbi.nlm.nih.gov/pubmed/6020216

Re: Prenatal testosterone linked to long-term effects in females with male twin

#46

Post by tofof »

codeisawesome wrote: post #30
tofof wrote: post #26

Earlier quoted context omitted.

The researchers never once use the term 'life success'. [1] That a behavioral difference (marriage rate) seems to be influenced, in females, by in-utero exposure to testosterone (independent of any effect on fertility rate, at that) is certainly a scientifically relevant finding. Links between psychology and biology are still infrequent. 1: https://www.pnas.org/content/early/2019/03/14/1812786116

Agree. But it was listed clustered with “college/school graduation likelihood, wage earnings, fertility (again hmm for this one)” and other indicators which are arguably termable as life success metrics (or any other suitable verbiage).. my point is that “one of these things is not like the others”.

Marriage rate differences have already been shown to be correlated with hormone levels.[1][2] Measuring whether such a difference exists for the level of exposure in-utero simply by having a male twin is interesting. If anything, the natural interpretation of this data would be to expand the range of behavior (marriage rate) considered 'typical' for females.

Similarly, fertility differences have been observed already for e.g. mice exposed to different levels of testosterone in utero. The 'freemartin' cows mentioned by another poster here are infertile for a similar reason. Hormones play a huge role developmentally and are almost 100% responsible for morphological sexual anatomy.

There's no agenda present in measuring these outcomes. These are exactly the outcomes that would be expected naturally to be different. If anything, the unusual inclusion is the economic and educational factors.

1: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5501487/

2: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3540120/

Re: Prenatal testosterone linked to long-term effects in females with male twin

#47

Post by jessaustin »

msviss wrote: post #41
jessaustin wrote: post #37

Earlier quoted context omitted.

It is so nice to come on HN and get some relief from the monotonous humorlessness that is life in USA today. For a moment, I imagine that I can laugh at funny statements no matter which way they point politically, rather than restricting my entertainment to grumbling in approved ways about whomever we're supposed to despise now.

You know I can’t figure out if your sarcastic or not? Either way, funny!

Haha, rereading that, it came out a lot more ambiguous than I had intended...

Re: Prenatal testosterone linked to long-term effects in females with male twin

#48

Post by tofof »

toolslive wrote: post #45

any advantages for the females with a male twin, like increased athleticism ?

Previous research has shown females with a male twin to be more proficient at mental 3d-spatial tasks.

As that paper explains in its introduction, this is "probably the most robust cognitive sex difference", emphasis mine, which is why it's interesting.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4438761/

Re: Prenatal testosterone linked to long-term effects in females with male twin

#49

Post by tofof »

olau wrote: post #42
tofof wrote: post #24

Earlier quoted context omitted.

> How does prenatal test affect someone after they've gone through puberty The test doesn't affect them. Hormone levels during development are the primary way the body controls development, so even small alterations in hormone levels in utero would be expected to have large physiological consequences. > Is that not a far reaching statement to associate the two Luckily, the field of statistics gives us ways to reason…

> Luckily, the field of statistics gives us ways to reason about whether or not to believe an observed effect. What you mean is correlation, right? Effect would imply causation.

No, I mean effect, i.e. causation.

In this case* the direction of the correlation is 100% knowable: economic and education outcomes in the 1990s cannot possibly have altered whether or not you had a male twin in the 1970s, unless you can reverse time's arrow.

*The OP was specifically asking about marriage rate and education outcomes. The paper also examined fertility. It's at least remotely plausible that there's some 3rd/confounding biological mechanism that actually the cause of both the presence of a male twin and the increased fertility of the female twin. In that case I would agree that 'correlation' is the more appropriate choice of term, but note that it's still correct in that case to assign 'effect' to both of the observed properties as they'd be downstream of the confounder.

Re: Prenatal testosterone linked to long-term effects in females with male twin

#50

Post by alwaysanagenda »

tofof wrote: post #44
alwaysanagenda wrote: post #43

Has nobody recognized that not a single biologist, chemist, neurosurgeon, hormone specialist, neo-natal specialist, or just general medical doctor participated or helped produce this study? Here are the authors: Aline Bütikofer - Department of Economics, Norwegian School of Economics, 5045 Bergen, Norway David N. Figlio - School of Education and Social Policy, Northwestern University, Evanston, IL 60208 Krzysztof Kar…

Why do you suggest fields other than anthropology or economics should be the qualification for analyzing population-level economic effects? Are you aware that the vast majority of scientific research is done by PhDs, not MDs? And that both are doctorates? > ... propels an agenda. This is propaganda of the highest order. What's the agenda? And did that agenda apply to the 2011 paper calling for more research in this a…

Because the presupposition is that testosterone exposure in-utero is to blame.

Without actually addressing this claim by medical professionals, everything else is manipulation of data to prove a point to address 'social policy' or an economic agenda.

Moreover, the sample size, location, and dates of birth, are small and narrow, comparatively speaking. You cannot make sweeping claims like this using such small data set. But they do, and the "Material and Methods" section of this paper goes to great length to explain how they've made these extrapolations.

This is statistical sausage.

I have no doubt you could write a similar paper that claims the opposite; that females with male twins do much better. Just like this team did, you can find, extrapolate and present data to support the idea.

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