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[OBG] Sexual selection explains sex and country differences in fluid g
I shall approve after these changes:

Line 23:
hyphen for "problem-solving ability"

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comma after "(Skuse, 2005)"

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no comma between "intelligence" & "because"

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semicolon, not colon, after 1952

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commas after "al." & "Price"

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period before quotation mark

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space between g & "r=0.454;"

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run, not ran

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put period at end of sentence

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comma after "N=44)"

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zero before decimal "0.285"

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run, not ran

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zeroes before decimals "0.008" "-0.395" "0.016"

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take italics out of "a" in "and"

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space between "variable," and "and"

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zero before decimal "0.453"

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there should be no comma between "SD" and "was"

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there should be no comma between "provided" and "because"

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add comma between "variables" & "and"

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add comma between "far" & "a"

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change "nationality, thus samples" to "nationality. Thus, samples"
I shall approve after these changes:

Ok thanks for your corrections. I've made all your requested changes and uploaded the corrected manuscript.
Good, but you missed these:

Line 258:
run, not ran

Line 273:
zeros before decimal "0.008"
Good, but you missed these:

Line 258:
run, not ran

Line 273:
zeros before decimal "0.008"

Ok thanks. Attached the corrected paper.
Ok we've got three reviewers approving: Ken Kura, Nooffensebut, Chuck.
Seems I was too late, too slack. I have still one question I would like to ask. It concerns this passage :

moderate levels of sexual selection will increase male relative to female variance, whereas strong sexual selection will push male variance back to lower levels through the process of fixation of favourable alleles and extinction of deleterious ones.

Can you be more specific about this ? I have the impression that you posit 2 distinct mechanisms. But, say, if having a husband with high IQ is always more adaptive, I would think that even at moderate or high level of selection, their variation would decrease in both cases.

That being said, in Table 1, you should correct for this :


The average score of two neighbouring countries (Albania: 0.245 and Bosnia&Herzegovna: 0.201) from the 2013 report was used instead.

line 317

the finding by Piffer (2014) that population frequencies of alleles known to increase height had a strong inverse correlation between populations to frequencies of alleles that increase IQ

And add a dot at the end of the sentence.
My argument is very complicated and pretty speculative. A direct test of it would require statistical modelling with computer simulations.Mine is just a tentative interpretation of this very interesting result that male variance is higher (which supports X linkage) but the ratio of male:female SD is lower in populations with higher dimorphism (with stronger sexual selection).
My argument is this: mutations present on the X chromosome will increase male to female phenotypic variance due to the hemizigous males vs heterozygous female effect (males have higher variance because all males will show the phenotype due to the "male affected/female carrier" effect). Sexual selection will thus increase male relative to female variance because mutations on the X chromosome are not wiped out. However, this effect will be counterbalanced once the mutations become fixed, because all males will have that allele, hence exhibit the same phenotypic effect thus reducing the variance.However, also all females have that allele, reducing their variance too. Let x be a recessive allele.
If x has 50% frequency among females, 25%of them will show the phenotype (0.5*0.5) and 75% will not.
Once x reaches 100%, all females will have the phenotype.
Among males, if x has 50% frequency, 50% will have the phenotype.When x reaches 100%, all of them will have the phenotype. So the males will have gone from 50% exhibiting the phenotype (50% corresponding to maximum possible phenotypic variance), to 100% having it (with 0 and 100% representing minimum variance). This corresponds to a reduction of 50% (100-50)
Conversely, female wil have gone from low variance (25%) to minimum variance (0%). This correspond to a reduction of only 25% in variance.
Hence, female variance will decrease less than male variance if alleles are driven to fixation.
G is most strongest related to working memory tasks implying general factor is mostly likely processing efficiency of a supervisory attention network. There are no evidence of sex difference in working memory tasks like the n-back and sex differences on IQ tests is simply a result of broad domain abilities like Gv (Raven's progressives). So no, there are no convincing evidence of sex differences in general factor. Sexual selection of Gv (visuo-spatial ability) in men is most plausible since men from prehistorical h/g societies may have traveled hundreds of kilometers in finding a mate. Navigation is obviously causal to Gv abilities like visualworking memory.