/sci/ - Science & Math

>>14546972
Brain size is correlated with visuospatial IQ, but has virtually no correlation with verbal IQ. Relevant:
https://www.unz.com/akarlin/cognitive-cliodynamics/

>Two other bits of evidence from HBD. First, larger-brained men have a 10 IQ point advantage in visuospatial ability over women, but verbal abilities are at best equal. The Inuit and Yakuts have some of the biggest brains on the planet, more so even than their other Mongoloid cousins, but while their visuospatial abilities are legendary – early Soviet psychometrists noted the ability of the Altai to notice one missing animal in a herd of hundreds – their verbal IQs are nothing to write home about. Meanwhile, Jews dominate verbal IQ, being almost one S.D. above Whites, while having normal sized brains and unremarkable visuospatial IQ.

>Verbal skills, in contrast, benefit little if at all from greater brain size, and children in the developed world were already getting very stringently trained on it even a century ago. Even brutally so (spare the rod and spoil the child; one beaten is worth two unbeaten; etc.). OTOH, there must have been a large improvement in average verbal proficiency between, say, 1600 and 1900.

>Verbal skills are much more important for economic productivity than recognizing patterns in weird shapes, ergo GDP per capita and development levels showing the highest levels of correlation precisely with verbal IQ. Incidentally, this is why I find PISA tests – which are both strongly g loaded, as well as focusing on precisely the most economically useful skills – to really be the most useful psychometric tests from a real world perspective, as opposed to Lynn & Vanhanen’s and David Becker’s laudable efforts.

>>12132229
>Pic related.

>>11939465
https://www.unz.com/akarlin/cognitive-cliodynamics/

>Raven’s loads heavily on visuospatial ability, which in turn is highly dependent on brain size. OTOH, verbal ability to seems to have little, if any, correlation with brain size.

>Brain size increased by well more than an S.D. since the late 19th century, in line with increased in body size as a whole [see the book The Changing Body by Floud et al. for a comprehensive treatment]. However, people familiar with classical literature, with contemporary journals, magazines, and letters, etc., could be understood for dismissing this on account of it just being too incredible.

>At it happens, they would be right to do so. According to one study (Henrichsen et al., 1986), which was highlighted by IQ blogger Pumpkin Person, fourteen pairs of MZ twins who had weight differentials of more than 25% at birth had their bodies and minds measured at the age of 13. The heavier twins had a 0.5 S.D. higher head circumference, a 0.5 S.D. higher performance IQ, but there was no difference in verbal IQ.

They weren't subject to Clark-Unz selection like Eurasians were.

https://www.unz.com/jman/more-on-farming-and-inheritance-systems-part-i-iq/
https://www.unz.com/jman/iq-ceilings/
https://www.unz.com/pfrost/more-on-clarks-model/
https://www.unz.com/pfrost/final-thoughts-on-clark-unz-model/
https://www.unz.com/pfrost/origins-of-black-africans/

>>11275572
Hydrocephalus, just water.

>>11275576
Here's a map showing the differences in brain volume, which can be explained reasonably well by Bergmann's rule.

>>10791036
IDK too much about other native American tribes, but plenty of them seem to have large craniums.

>>10647174
No.

>>10295797
Visuospatial intelligence is significantly correlated with cranial capacity. Less so for verbal intelligence.

https://www.unz.com/akarlin/cognitive-cliodynamics/

>>10253041
>human variation is "superficial" and "skin deep"
"no"

>>10228841
https://www.unz.com/jthompson/asians-bright-but-not-curious/
https://www.unz.com/akarlin/the-evolution-of-chinese-iq/
https://www.unz.com/akarlin/cognitive-cliodynamics/
https://www.unz.com/jman/zigzag-lightning/

>>10221513
Africans faced different selection pressures than Eurasians did. Life and death in African may have been more random, with foresight less reliable rewarded and lack of planning less reliably punished, so Africans might be more r-selected whereas Eurasians might be more K-selected. Large cranial capacity may have also been harmful in Africa due to the risk of overheating. In Europe and Asia, Clark-Unz selection contributed to higher IQs, with higher class people with higher IQs having roughly twice as many surviving offspring on average compared to lower class people.

https://www.unz.com/jman/more-on-farming-and-inheritance-systems-part-i-iq/
https://www.unz.com/jman/iq-ceilings/
https://www.unz.com/pfrost/origins-of-black-africans/
https://www.unz.com/pfrost/more-on-clarks-model/
https://www.unz.com/pfrost/final-thoughts-on-clark-unz-model/
https://www.unz.com/akarlin/genetics-iq-and-convergence/
https://www.unz.com/isteve/africas-lack-of-malthusian-trap/

>>10204857
>phrenology is craniology
why do brainlets always make this mistake?

>>10200275
Larger brain size is significantly correlated with higher visuospatial IQ, but less with verbal IQ.

https://www.unz.com/akarlin/cognitive-cliodynamics/

looks about right to me

>>6903512
>Oh wait they don't.
[citation needed]