Just as mainstream wisdom on human psychology and evolution is filled with heaps of rubbish (rubbish which I've covered here extensively – see 200 Blog Posts – Everything You Need to Know (To Start)), the space of dissenting voices on this matter is also filled with its own share of rubbish – and worse. I've... Read More

A vigorous discussion has been triggered by the release of Gregory Clark's The Son Also Rises: Surnames and the History of Social Mobility. In this book, Clark details his work which shows a large transmission of status from generation to generation, all across the world, going back centuries. The discussion has raged on the mode... Read More

Post updated, 9/13/14. See below! I haven't always made it explicit, but some of you might gather that I am rather hard on most "environmental" explanations. You have inferred correctly. The reason? Several, which I'll review here. The biggest of these? There is no good evidence for the vast majority of them. That's right, there... Read More

Luke the Evangelist (source: British Library). In the past, only a minority could read long texts of cursive writing. But many more could read short texts of block writing. The Visual Word Form Area (VWFA) is a specialized part of the brain that helps us recognize written words and letters. If it is subjected to... Read More

Updated, 10/17/15. See below! In this post, I will review Gregory Cochran's "gay germ" hypothesis. I wanted to make an index of Cochran's posts from his and Henry Harpending's blog West Hunter that discuss it. These posts don't seem to all show up under the "Homosexuality" category there, and I wanted links to them to... Read More

Ethiopian manuscript paintings (source: A. Davey). Ethiopians have a self-image that is lighter-skinned than their actual selves. If the prevalence of SLC24A5 is higher in Ethiopia than the degree of admixture from lighter-skinned peoples across the Red Sea, this discrepancy may be explained by social selection for lighter skin. Greg Cochran has been asking why... Read More

When did early Europeans acquire their palette of eye colors? And their palette of hair colors? That question may soon be answered with retrieval of ancient DNA. (source: Dipoar) As the new year begins, I’m particularly interested in the following topics. When did Europeans begin to look European? It seems that this evolution took place... Read More

Interior of a magasin général (source: photographiquement Frank). Wherever there was less competition from British or American merchants, it was easier for French Canadians to go into business. These same regions also have unusually high rates of neurological disorders, including Tay-Sachs. Coincidence? French Canadians have a unique demographic history. From a founding population of some... Read More

In his most recent post, Greg Cochran quipped that since corporal punishment is a quiet issue these days, it likely works. EDIT: That is, it works in keeping kids in line at school, and only that. Needless to say, the map of states with legal corporal punishment in schools follows the Map of the American... Read More

Readers here will recall my recital of Greg Cochran's hypothesis that obligate male homosexuality is caused by a pathogenic agent, likely a virus (please see 100 Blog Posts – A Reflection on HBD Blogging And What Lies Ahead: Homosexuality (the “gay germ” hypothesis)). This is by far the most likely explanation for male homosexuality (see... Read More

This is my 100th blog post. Upon reaching this milestone, I thought that this would be a great time to take moment to look back at my experience as a blogger in Human BioDiversity (HBD) and share my thoughts on the things to come. 1. The Beginning 2. Fertility 3. Immigration and the economy 4.... Read More

For the record, one can be liberal (as I am) and be against continued mass immigration. Check out these folks: Once every few decades, the stars align for major immigration legislation. According to political analysts, the United States may be at such a juncture now. Barack Obama’s re-election as President has concentrated politicians’ attention on... Read More

Incidence of chlamydia, a major cause of infertility. The high polygyny rate among the “female farming” peoples of sub-Saharan Africa may have favored the evolution of STDs. Is this where we should look for the precursor of the hypothetical “gay germ”? (source) Heritability for male homosexuality is low to moderate (30 to 45%). There is... Read More

A Parsi woman in traditional costume, painted by Raja Ravi Varma (source) The Parsis are renowned for achievement in many areas of life—trade, education, philanthropy, and popular culture. Yet they number only about 100,000 in the entire world (Wikipedia, 2013). What qualities made them so successful? The most often-cited ones are their thrift, foresight, skillfulness,... Read More

A recent article in the UK Daily Mail featured the "Weight of the World" chart made by Visual.ly. It graphically represents the average body mass index (BMI) of the inhabitants the countries of the world. In keeping with my recent series on the matter, I wanted to see what it'd look like if I turned... Read More

Greg Cochran argues that it is highly likely that exclusive male homosexuality is caused by an infectious agent, likely a virus. As he explains, there are several good reasons to suspect that this is the case, including: the low heritability of male same-sex attraction (0.22) the absence of homosexuality in hunter-gatherer populations the relatively high... Read More

Recent research, such as by historical economist Gregory Clark, suggests that differences in mental and behavioral traits cannot always be ascribed to different reproductive strategies, as Philippe Rushton suggested. There probably will never be a unified theory of human biodiversity … other than the theory of evolution by natural selection. Last March, I was asked... Read More

Do older fathers have dumber children? For the past millennium, paternal age has been relatively high in Europe west of the Hajnal line. Yet, if anything, mean IQ is higher there than elsewhere. H/T to JayMan (source) Greg Cochran has been running a series of posts on paternal age and IQ (here, here, and here).... Read More

Does higher IQ correlate with colder temperatures? Not among people belonging to the same cultural system, such as the Chinese. (source) Big brains are costly, not only because of their high energy consumption but also because many genes have to interact to create neural tissue. The bigger and more complex the brain, the more it... Read More

Greg Cochran and Henry Harpending have recently proposed a hypothesis on their blog that posits that the lower average IQ of tropical peoples may be related to the number of fitness reducing mutations these people carry. Apparently, the rate of mutation is higher in the tropics. The majority of mutations that occur are neutral and... Read More

What causes exclusive male homosexuality? This is the question I’ve addressed in the last few posts. The answer is still elusive although there seems to be consensus on some points. One such point is the relative importance of inborn causation versus environmental causation. In men, an exclusively homosexual orientation has a heritability of 30-45%. A... Read More

One point is often raised about male homosexuality: it has always been with us. True, but has it ever changed in its nature or prevalence? Well, more gays have been ‘coming out of the closet.’ People are practicing openly what used to be done in secret. But have there also been more fundamental changes? Such... Read More