Researching the genomics of intelligence using extant & extinct humans


, , ,

Lion of the Blogosphere has an interesting article up about the genomics of height and intelligence. He writes:

Height, like intelligence, is a complicated polygenic trait involving hundreds, probably thousands, of genetic variants.

It’s interesting how the discussion has changed in recent years from genes to genetic variants. I even go further and now use the term “genomic variants”.

Lion continues:

But unlike intelligence, it’s not politically incorrect to study the genetics of height, or to assume that if a particular ethnicity is very tall or very short, then it’s because of genetics.

Because if you say a person or ethnicity is genetically smarter, we equate this with genetic superiority, a concept many people find offensive.

But in a way calling a group genetically taller also implies genetic superiority. Height is right up there with intelligence as one of the most universally valued traits. Not only do most women not want to date a guy under 5’9″ but sperm banks don’t even accept their sperm because they’re considered genetic trash.

The culture is awash in height supremacist metaphors: We “look up” to those we admire and “look down” on those we disdain. Taller men make more money, achieve more education, and are more likely to lead corporations and entire nations. “Standing tall” is a metaphor for having dignity.

But of course intelligence is what makes us human. Height is not.

Lion continues:

Thus, it’s interesting that scientists have discovered a single genetic variant that contributes to Peruvians being short.

The same techniques could be used to investigate intelligence. It would be beneficial to study the smartest ethnicity (Ashkenazi Jews) and extremely low-intelligence ethnicities like Aboriginal Australians and southern African Bushmen. I’m sure if we did that, we could discover additional genetic variants related to intelligence.

Scientists are working hard on exactly this, but because it’s politically incorrect to label any extant human populations “low intelligence”, they are instead focusing on extinct ones like Neanderthals. From a New York Times article about Svante Paabo, who played a major role in sequencing the Neanderthal genome:

 Reconstructing a Neanderthal genome was a tour de force, we can all agree, but why does it matter?

Paabo spends only a little time directly addressing this question. He argues that the Neanderthal genome can serve as a counterpoint to our own. It enables Paabo and his colleagues to draw up a list of mutations that our ancestors acquired after they split from Neanderthals. Among those mutations may be changes that led to our capacity for language, symbolic thought or the other traits that make us uniquely human. states:

 These genes may hold key clues to the behavioral differences between modern humans and the extinct, archaic human species. According to Svante Pääbo of the Max Planck Institute, they could constitute “a catalog of genetic features that sets all modern humans apart from all other organisms, living or extinct.”

“I believe,” he added, “that in it hide some of the things that made the enormous expansion of human populations and human culture and technology in the last 100,000 years possible.”

Steve Hsu writes:

What Homo Sapiens accomplished in 50-100k years far outstrips Neanderthal accomplishments over a much longer period of time.

So Pääbo is hoping that by studying the genomic variants that distinguish virtually all anatomically modern humans from virtually all Neanderthals, he’ll discover why our species colonized the entire planet, invented civilization and went to the moon, while Neanderthals languished in the stone age for hundreds of thousands of years.

All this assumes the biggest evolutionary changes occured after we split from Neanderthals some 500,000 years ago, but before human races split from each other, maybe 70,000 years ago for people outside of sub-Saharan Africa, maybe 150,000 to 250,000 years ago for the various groups in sub-Saharan Africa .

But what if the biggest changes are very recent? In 2007 stated:

Plentiful food has made it easier than ever before to survive and reproduce in many parts of the world, so it’s tempting to think that our species has stopped evolving. But a controversial new study says that isn’t so. Far from slowing down, human evolution has sped up in the past 40,000 years and has become 100 times faster in the past 5000 years alone, according to the analysis.

So should we think of the last 5000 years as half a million years of evolution?

From a 2007 article in REUTERS:

Human evolution has been moving at breakneck speed in the past several thousand years, far from plodding along as some scientists had thought… In fact, people today are genetically more different from people living 5,000 years ago than those humans were different from the Neanderthals who vanished 30,000 years ago …

But if they were more similar to Neanderthals, why are they considered members of our own species, and if so much evolution has occurred in the last 5,000 years, how did we manage to look fully modern by 195,000 years ago (the age when our species first categorically appears in the fossil record)?

Are IQ tests based on circular logic? A reply to Race Realist


, , , , , , ,

Commenter Race Realist (RR) wrote yet another article claiming that IQ tests are based on circular logic and just measure social class. He writes:

In sum, what these tests test is what the test constructors presume—mainly, class and racial bias—so they get what they want to see. If the test does not match their presuppositions, the test gets discarded or reconstructed to fit with their biases…At best, IQ test scores measure the degree of cultural acquisition of knowledge; they do not, nor can they, measure ‘intelligence’—which is a cultural concept which changes with the times. The tests are inherently biased against certain groups; looking at the history and construction of IQ testing will make that clear. The tests are middle-class knowledge tests; not tests of ‘intelligence.’

RR is right that IQ tests were originally designed to confirm existing prejudices of who was smart by deliberately selecting test items that so-called smart people did better on. This is ironic because the whole point of creating an IQ test was that teachers’ judgments were considered too biased to trust, so why did the first IQ testers rely on teachers to decide who was smart?

Psychometric tasks are great at being objective, but they’re not always great at measuring intelligence. By contrast teachers are great at judging intelligence, but they’re not always objective. Thus by selecting only those test items that most confirmed teacher judgement, they got the best of both worlds: An objective scale that was great at measuring intelligence.

Of course RR might argue that the teachers were just judging social class, not intelligence, and by extension so were the tests. Further he would argue that if the tests predicted socioeconomic success, it was not because smart people rise to the top, but rather because SES is all the tests were measuring in the first place.

However we now know that IQ tests predict life outcomes, not because they correlate with teacher’s judgments, but because they correlate with g; the general factor of IQ tests.

Thomas R. Coyle writes:

g is one of the best predictors of school and work performance (for a review, see [7], pp. 270–305; see also, [8,9]). Moreover, a test’s g loading (i.e., its correlation with g) is directly related to its predictive power. In general, tests with strong g loadings correlate strongly with school and work criteria, whereas tests with weak g loadings correlate weakly with such criteria. For example, Jensen ([7], p. 280) found that the g loadings of the Wechsler Adult Intelligence Scale (WAIS) subtests were directly related to their predictive power for school criteria (e.g., school grades and class ranks). WAIS subtests with stronger g loadings generally predicted school criteria well, whereas subtests with weaker g loadings predicted such criteria poorly. Consistent with these findings, Thorndike [10] found that g explained most of the predictable variance in academic achievement (80–90%), whereas non-g factors (obtained after removing g from tests) explained a much smaller portion of variance (10–20%). Similar results have been found for job training and productivity, which are robustly related to g but negligibly related to non-g factors of tests (e.g., rnon-g < 0.10, [7], pp. 283–285; see also, [9,11]).

From Non-g Factors Predict Educational and Occupational Criteria: More than g

g is whatever variable(s) causing all cognitive abilities to positively inter-correlate. RR will tell you g is circular logic because any cognitive ability that doesn’t correlate with g is excluded, but this is false.

As Arthur Jensen (1998) noted, there are very clear rules on a) what is an ability, and b) what is a cognitive ability, and none of them require a correlation with other cognitive abilities.

A test measures ability if it a) measures voluntary behavior, b) has temporal stability, c) has a clear standard of proficiency, and d) some generality. There is another set of criteria that determines whether a particular ability is mental or physical.

IQ skeptics can cite tests that don’t correlate with g, but these tests don’t qualify as ability measures. One example are so-called creativity tests where you’re asked to name as many uses for a brick as you can think of in two minutes. Such tests often lack a clear standard of proficiency because silly answers (i.e. use it to comb your hair) get the same credit as good answers (use it to smash a window).

No one to my knowledge has come up with a mental test that actually qualifies as an ability test yet does not correlate with g with the possible exception of the BITCH test (ironic name for a test that’s supposed to fight anti-black bias) however the BITCH test is clearly culturally biased. None of the major IQ tests are culturally biased against any of the founding racial subgroups of the United States (at least as defined by psychometric criteria).

Khalid Muhammad on Donahue

I enjoyed watching this old episode of Donahue on Youtube. A few people have mocked and endlessly attacked me for my obsession with daytime talk shows, but the 1990s was really the golden age of the genre. I’m certainly not a fan of modern daytime TV and never watch it.

But then I’m biased because it’s what I grew up on. I’m a product of late 20th century suburbia and because both my parents worked outside the home, talk show hosts became my surrogate parents.

But maybe if I grew up in the 21st century inner-city like commenter Loaded, I would admire rappers instead.

IQ is largely destiny: the Jeffrey Epstein case

Youtube has these provocative conspiracy discussions about Jeffrey Epstein (watch before they get banned).. One throwaway comment was that Epstein was stupid. He famously misspelled his own name on a chalk board because he couldn’t adapt to writing with chalk and he also misspelled virgin, even though he spent his life preying on them.

Apparently only a stupid man would be so brazen as to blackmail the most powerful people in society with sex tapes, and that’s why the low IQ Epstein was recruited.

But because IQ is largely destiny, he never did become the billionaire he wanted so desperately to be, and things ended badly for him in prison.

Rare footage of Oprah’s father

I enjoyed this clip from a 1992 episode of Oprah’s syndicated talk show, where she returns to Nashville Tennessee to visit her father, Vernon Winfrey, as well as the men who gave her her first jobs in radio and TV.

No one knows for sure if this really is Oprah’s biological dad; he was just one of many men her mother had been with before getting pregnant. One family member suspects he’s not her real dad because Oprah was born with a “photographic memory”; something Vernon lacks.

Bill Gates & Executive Functioning


, , , , , ,

Like many of the greatest minds in STEM, Bill Gates has been accused of having a touch of autism by armchair psychologists. Others argue he is simply a nerd.

While some argue that nerdiness is a mild form of autim, others, like LOTB, argue that the two concepts are distinct.

I have not done enough research to have a strong opinion either way, but a key deficit in autism involves executive functioning.

What is executive functioning?

Executive functions (collectively referred to as executive function and cognitive control) are a set of cognitive processes that are necessary for the cognitive control of behavior: selecting and successfully monitoring behaviors that facilitate the attainment of chosen goals. Executive functions include basic cognitive processes such as attentional controlcognitive inhibitioninhibitory controlworking memory, and cognitive flexibility. Higher order executive functions require the simultaneous use of multiple basic executive functions and include planning and fluid intelligence (e.g., reasoning and problem solving)

source: (2019-11-24)

What does any of this have to do with Bill Gates? My subjective impression is that Gates is relatively weak at EF. Perhaps not compared to the average person, but certainly compared to his super IQ matched peers. In support of this impression are three (admittedly weak) pieces of evidence.

1) He sucked at petals around the rose

If you’ve never heard of this game please check it out and record how many dice rolls it takes you to get six consecutive correct scores.

Then compare your performance to Gates’s.

This game strikes me as very similar to the Wisconsin Card Sorting Test (a common measure of EF) in that it requires you to infer a rule based on repeated feedback. I infered the rule simply from the name of the game even before any feedback.

In Gates’s defense, he thought the game was called “pedal around the roses”, so this may explain his poor score.

2) He can’t control his hands

Anyone who has watched Gates in interviews knows how erratically his hands move around when he talks. I’m no neurologist, but this strikes me as an inability to inhibit certain responses, a lack of cognitive control or self-monitoring, and poor communication between the left and right brain. I tend to overuse my hands when I talk too so I see a bit of myself in Gates but I was insecure enough about it to stop.

I also have a problem where whenever I wave to someone, I also say “hi” even though they’re often too far away to hear me. I think this relates to the huge gap between my verbal (left-brain) and performance (right-brain) IQs. In extreme cases this can lead to unbuttoning your shirt with your left hand while simultaneously buttoning it up with your right-hand, thus never getting undressed.

3) He’s not that articulate

Despite the fact that Bill Gates’s verbal SAT score equates to a spectacular verbal IQ of 157, he’s not an especially impressive impromptu speaker. As commenter ” caffeine withdrawals” noted, he’s clearly above average, but not much more than that.

A professor of linguistics informed me that based on factor analysis, linguistic ability is actually three different abilities: vocabulary, working memory, and executive functioning. We know from Gates’s sky high verbal and math SAT scores that he’s likely extremely high in the first two, so only the third factor could be dragging down his speaking skills.

How does EF affect speaking skills? EF is all about planning and if you can’t plan your sentences and paragraphs in real lime, they wont be especially succinct. EF also relates to fluency because a certain amount of flexibility is needed to find the right word to express a given thought. People who perseverate too much on one word, or one type of word, will not be smooth talkers.