Showing posts from April, 2018


Why can't the NBA solve its diversity problem?  Hardly anybody worries about this.  Actually, my post was stimulated by a somewhat parallel article asking Why can't Silicon Valley solve its diversity problem?  Anna Wiener, and apparently lots of other people worry about that.  The reason that the first question is less interesting is that everybody knows the answer: the best players are almost all not white, Mexican, Asian, or women and none of the very best players are any of those.  Of course that doesn't solve the riddle of why the best players don't much come from those groups, but I've never heard it attributed to systematic discrimination in the NBA against them.

Would it be racist to attribute the paucity to Bergmann's rule, the biological generalization that notes that animals living in colder climates have stockier bodies and shorter limbs, an adaptation that conserves heat but sacrifices some speed and agility?  Some would say so, because admitting th…


Whether or not he is a total jerk has no relation to whether or not he is a significant artist.

Just sayin'.

Angry Young Men

The Rolling Stones:
I can't get no satisfaction, I can't get no satisfaction'Cause I try and I try and I try and I tryI can't get no, I can't get no Nearly all of the mass murders that we have seen in the West are committed by young men - very angry young men.  The Toronto van murderer and his inspiration seem to have been angry about the fact that women didn't like or accept them.  Others attach their rage to some cause or other - Islam or White Power, or whatever.  There are angry old men too, of course, though they seem a bit less likely to express their rage in the mass murder of strangers.  Despite the occasional angry woman, like the YouTube shooter, women seem much less likely to express their anger in mass murder.

Anger is not a mental illness, but it socially dangerous.  It is striking how many of the recent mass murderers were identified as serious threats long before they committed their crimes.  A few even had their guns confiscated, but they managed…

India: Politics and Genomics

David Reich:
The tensest twenty-four hours of my scientific career came in October 2008, when my collaborator Nick Patterson and I traveled to Hyderabad to discuss these initial results with Singh and Thangaraj. Our meeting on October 28 was challenging.   Singh and Thangaraj seemed to be threatening to nix the whole project. Prior to the meeting, we had shown them a summary of our findings, which were that Indians today descend from a mixture of two highly divergent ancestral populations, one being “West Eurasians.” Singh and Thangaraj objected to this formulation because, they argued, it implied that West Eurasian people migrated en masse into India. They correctly pointed out that our data provided no direct evidence for this conclusion. They even reasoned that there could have been a migration in the other direction, of Indians to the Near East and Europe. Based on their own mitochondrial DNA studies, it was clear to them that the great majority of mitochondrial DNA lineages pres…


I have been reading David Reich's Who We Are and How We Got Here: Ancient DNA and the New Science of the Ancient Past.  Svante Pääbo and his colleagues at the Max Planck Institute developed techniques for extracting DNA from very old bones.  One of his early apprentices was David Reich, who established a lab at Harvard and has "industrialized" those techniques (his description) and since produced a huge portion of all the analyzed ancient DNA.  His new book is about those methods but mostly about the surprising facts that they have revealed about our ancestry.  Perhaps the most surprising fact is that nearly all human populations have been formed by repeated large scale mixing events.

Today the population of western Eurasia is relatively homogeneous, but 14000 years ago, the area was occupied by at least four distinct populations as different from each other as modern Europeans are from modern East Asians, according to Reich.  Modern Europeans are a mixture of those four…

Chick Shortage

The two big cultures on the most populous continent both prize males above females. Modern medical technology permitting sex selective abortions turned this age old preference into a major undersupply of females in the population. The Straits Times has a big story on it.

A combination of cultural preferences, government decree and modern medical technology in the world's two largest countries has created a gender imbalance on a continental scale. Men outnumber women by 70 million in China and India. The consequences of having too many men, now coming of age, are far-reaching: Beyond an epidemic of loneliness, the imbalance distorts labour markets, drives up savings rates in China and drives down consumption, artificially inflates certain property values, and parallels increases in violent crime, trafficking or prostitution in a growing number of locations. I found the story interesting throughout, but I want to focus on just one aspect.  The shortage of women has driven up savin…

The DNA Shuffle

We inherit half our DNA from each of our parents, but that DNA is shuffled in a couple of ways before we get it. This results in our inheriting our parents DNA in roughly 118 separate segments. That number increases by about 71 segments for each additional generation. The number of our ancestors, or at least the number of slots in our family tree, though, doubles every generation. Consequently, by the time we get to the tenth generation, we inherit about as many segments as we have ancestors, and by the twentieth generation, only about 0.1% of our genealogy actually contributes DNA. David Reich: Yet even if the genealogies are accurate, Queen Elizabeth II of England almost certainly inherited no DNA from William of Normandy, who conquered England in 1066 and who is believed to be her ancestor twenty-four generations back in time.21 This does not mean that Queen Elizabeth II did not inherit DNA from ancestors that far back, just that it is expected that only about 1,751 of her 16…

How should you address a cat?

Especially when that cat is your professor? I tend to err on the side of formality, mainly because I'm an old guy, and tend to be very informal. My professors all address me and the other students by their first names, which is fine by me, and a lot of the students reciprocate. So am I being polite or a hopeless fuddy duddy when I address emails to "Dear Professor X?"


The trouble with boys, say a couple of new studies, is that they have too much confidence. It seems that an average boy is likely to believe that he is smarter than average while average girls are less likely to. Lots of studies show that this effect is pervasive in women of all ages - at least above the age of 5. Moreover, confidence is known to play a big role in success, even though the Dunning-Kruger effect is in action (less competent persons are more likely to overestimate their competence than the more competent. Anyone who doubts these two principles should consider the case of our chief executive. So does this pervasive effect just reflect the ongoing success of the patriarchy in keeping the womenfolk down, or is there a biological basis? My guess would be a bit of both. Boys who lack confidence are urged to "grow a pair." Girls wind up growing pairs of organs that don't produce testosterone. The most demanding and prestigious jobs in society require co…

Genetic Similarity and Differences

Arun takes exception to the following in the Big South Asia genomics paper: While the earliest 450 group of samples (SPGT) is genetically very similar to the Indus_Periphery samples from the 451 sites of Gonur and Shahr-i-Sokhta, they also differ significantly in harboring Steppe_MLBA 452 ancestry (~22%).What does that "similar but different" mean, he asks. I have a couple of ideas (and I can't currently use his comment system), so here goes. All human DNA is highly similar. Numbers like 99.5% identical are often mentioned, so comparing similarities and differences depend on the relatively few sites (millions, actually, out of billions) where differences occur, in this case, the so-called Single Nucleotide Polymorphisms (SNPs) or single site on the genome where more than one of the four possible nucleotides is found, that is, places where Joe might have a Guanine or G, and Fred might have a Thymine, or T. Thus, detecting similarities to ancestral populations depends…

Whoa! I am old!

I was looking at my student file at the local U and noticed that it included my GRE scores, and when I had taken the exams: Jan 1, 1888. That seems a bit early.

Genomics of India

Arun and his commentators have linked to and discussed an important new paper on the genomics of India by David Reich and the Harvard collaboration. This paper bears on a number of points dear to my interests, including the origins of the Indo-European languages. Among the zillions of theoretical locations for the PIE Urheimat, only three still seem to have any substantial support, with the Eurasian steppe near the Black Sea the overwhelming favorite. Number two seems to be the Iranian highlands, with the Out of India (OIT) theory championed almost exclusively by Indian nationalists. I'm not ready to discuss the paper yet, though I have read it, the broad conclusions suggest that the modern Indian population was formed by two major migrations mixing with the existing population, which may well have been there since the earliest spread of modern humans from Africa, and which has the Andaman Islanders and Australians as their closest relatives. The first major wave of immigrant…