The mysterious PC1 ancestry component

Mehta, C. M., Malins, J. G., Noble, K. G., & Gruen, J. R. (2017). Cortical area and subcortical volume mediate the effect of parental education and adverse experiences on cognitive performance in youth. bioRxiv, 160424. Remember “poverty shrinks the brain from birth”? From birth! Fast acting that poverty, actually before birth too. Anyway, Kimberly Noble…

Continue Reading

Race gaps in brain size in the very young

Most environmentalists have by now given up denying the existence of racial gaps in head size, but they only retreated a few yards: Nisbett, R. E., Aronson, J., Blair, C., Dickens, W., Flynn, J., Halpern, D. F., & Turkheimer, E. (2012). Intelligence: new findings and theoretical developments. American psychologist, 67(2), 130. Brain size and IQ….

Continue Reading

About that blog: Italian IQs, Lynn IQs, brain size and doctors

notpoliticallycorrect.me/ Twitter: RaceRealist88 Since I am repeatedly asked by a bunch of differently looking people to comment on that particular blog. I don’t know the guy, but he’s been quite active in recent times. The blog is kinda odd in that it prominently features race realist stuff, a bunch of prominent race realist academics —…

Continue Reading

Evolution and imperfect mediators

Skoyles, J. R. (1999). Human evolution expanded brains to increase expertise capacity, not IQ. Psycoloquy, 10(002). Chicago Skoyles is arguing a rather implausible claim: Why do modern humans have larger brains than earlier people such as Homo erectus? As large brains cause problems in childbirth, infancy and locomotion, the advantage they offer must be substantial….

Continue Reading

Cold winter theory in non-human animals

Disclaimer: I did not read Rushton’s seminal book on the topic. I was only first recently able to obtain a complete electronic copy (i.e. not abridged version). I did in fact only skim this literature. I don’t have time to work on this, but I’d like others to do so, hence I put the labor…

Continue Reading

Change in Egyptian skull sizes: -4000 to 150

I often read statistics textbooks. In textbooks, they often use example datasets, some of which are interesting in themselves (e.g. the Boston dataset). In this case, I am reading An Introduction to Applied Multivariate Analysis with R. It features a dataset of Egyptian skulls spanning about 4000 years. Given the scholarly interest in dysgenics and…

Continue Reading

The general brain factor, working memory, parental income and education, and racial admixture

UNFINISHED ANALYSIS. POSTED HERE TO ESTABLISH PRIORITY. MORE TO FOLLOW! Updated 2015-12-04 Remains to be done: Admixture analysis (doing) Proofreading and editing Deciding how to control for age and scanner (technical question) Abstract I explore a large (N≈1000), open dataset of brain measurements and find a general factor of brain size (GBSF) that covers all…

Continue Reading

Bouchard’s new review paper on Genes, Evolution, Intelligence is excellent!

Seriously. Read it. Behavior Genetics (Impact Factor: 2.61). 03/2014; DOI: 10.1007/s10519-014-9646-x Source: PubMed ABSTRACT I argue that the g factor meets the fundamental criteria of a scientific construct more fully than any other conception of intelligence. I briefly discuss the evidence regarding the relationship of brain size to intelligence. A review of a large body of…

Continue Reading