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Angela
20-08-16, 17:42
See:
http://www.ncbi.nlm.nih.gov/pubmed/27507146/

Sometimes I wonder how much total government spending goes toward research proving what we basically already know through common sense.

Yes, outgoing or extroverted people probably have more success with the opposite sex. Yes, extroversion is probably highly genetic in origin. That it's selected for in our highly "social" species is also not a surprise.

However, this kind of finding has limited usefulness. In the past, people's preferences, or the attractiveness of someone's "game", hardly entered into it. Marriages were for economic gain if at all possible: who had the most land, or the tenancy, or could bring some cows, and sheep, or pots and pans to the marriage.

"Personality has been associated with reproductive success in humans and other animals, suggesting potential evolutionary selection pressures. However, studies to date have only examined these associations on a phenotypic level, which may be inadequate in estimating evolutionary change. Using a large longitudinal twin dataset of contemporary Finns, we compared the phenotypic (breeder's equation) and genetically informed (the Robertson-Price identity) associations between lifetime reproductive success (LRS) and two personality traits-neuroticism and extraversion. Neuroticism was not associated with LRS at the phenotypic nor genetic level, while extraversion was associated with higher LRS in men both phenotypically and genetically. Compared to the univariate phenotypic analysis, the genetic analysis suggested a larger selection response of extraversion, and a selection response of neuroticism due to indirect selection. We estimated that neuroticism decreases by .05 standard deviations and extraversion increases by .11 standard deviations by one generation. Our results highlight the importance of considering genetic associations between personality and fitness and investigating several inter-related personality traits and their covariance with each other to predict responses to selection more accurately."

Coriolan
21-08-16, 15:07
If extraversion improves reproductive success then we should expect that most of the population would become extroverted over time. This is clearly not the case and in some countries like Finland it looks like traits for introversion have been selected for over time. There is also a North-South gradient for introversion-extraversion. Southern Europeans are much more extroverted than northern Europeans. So sexual selection is not everything.

arvistro
21-08-16, 15:44
If extraversion improves reproductive success then we should expect that most of the population would become extroverted over time. This is clearly not the case and in some countries like Finland it looks like traits for introversion have been selected for over time. There is also a North-South gradient for introversion-extraversion. Southern Europeans are much more extroverted than northern Europeans. So sexual selection is not everything.
This is Finnish research :)



See:
Sometimes I wonder how much total government spending goes toward research proving what we basically already know through common sense.

Perhaps it was not so common sense, at least for Finland :)
To be fair, I would also guess Coriolan was right, unless I noticed the research was Finnish.

davef
21-08-16, 17:08
@angela

Yeah I think its because these researchers want to do something (quick and easy at that) so they can get paid.

Angela
21-08-16, 17:09
Good catch, Arvistro! :)

Seriously, as I said, I don't think this would apply across the board in past eras. Girls on the marriage market most often did as they were bid and married their parents' choice, even if, as was often the case, he was older, not particularly attractive, and, to use an American expression, didn't have a word to say for himself. As far as girls are concerned, again, economic concerns were usually paramount, but even if not, it seems to me that perhaps in eras past a shy, biddable girl, as one less likely to stray even if married to an older man, might have been preferred.

I really think this would only apply to mating choices in the last hundred years or so, hardly long enough to have had an evolutionary effect.

In terms of the modern, post industrial western world, I do think it's common sense, certainly in any country I've ever been in, and perhaps even in Finland. :) Can they be more shy than the British, by the way? Once, in an English restaurant, I asked the waiter to move me to another table. I don't remember what excuse I gave, but the real reason was that I couldn't bear to listen to a poor man stumbling and stammering during an obvious first date. I empathize too much most of the time; I was almost as embarrassed as he was, I think.

Just to be clear, I wish it didn't work this way. I was pretty shy myself when I was young, as is my son.

Also, everything is relative. Even if, on average, Finns are far less extroverted than, say, Italians, there will be variation even in Finland, and I would bet a substantial sum that the less shy men there have more success with women.

arvistro
21-08-16, 20:23
Also, everything is relative. Even if, on average, Finns are far less extroverted than, say, Italians, there will be variation even in Finland, and I would bet a substantial sum that the less shy men there have more success with women.
Whilst I agree in general, technically shy and introvert are close but not the same concepts.
Since I am not an expert in this fields, I googled up shy extrovert and got a number of pages. So, apparently there are such people.

On other hand of course introverts are more likely to be shy. But by how much? That would be another research :)))

Angela
21-08-16, 21:54
Whilst I agree in general, technically shy and introvert are close but not the same concepts.
Since I am not an expert in this fields, I googled up shy extrovert and got a number of pages. So, apparently there are such people.

On other hand of course introverts are more likely to be shy. But by how much? That would be another research :)))

That sounds very interesting. I'm going to have to look up shy extroversion. Maybe that would describe me better.