Progress Daily

People who share genes tend to have similar IQs. The correlation between parent and child is 0.42. If you average both parents’ IQ scores, then the correlation rises to 0.72, indicating that children tend toward the average intelligence of their two parents. Siblings’ IQs correlate by a factor of 0.47, similar to the parent/child correlation of 0.42, which fits with the fact that both pairings share 50% of their genes.

The IQs of adopted children and their biological mothers correlate by a factor of 0.22, about half as much as when they are reared by them. Similarly, biological siblings adopted into different homes show a 0.24 correlation. Doubling these numbers, to correct for the fact that siblings or parent-child pairings share only half of the same genes, allows us to estimate that genes account for 40 to 50% of a person’s intelligence.

The IQs of identical twins reared apart correlate by a factor of 0.72. Fraternal twins show considerably higher IQ correlation than ordinary siblings, even though both pairings have the same proportion of genes (50%) in common, presumably because of their shared experience in the womb. Researchers believe that prenatal experience accounts for up to 20% of IQ variance. Subtracting this effect from the IQ correlation of identical twins reared apart (0.72) leaves genes once again accounting for about 50% of a person’s IQ.

The highest correlation is for identical twins reared together — a whopping 0.86 correlation. Fraternal twins reared together show a correlation of 0.60. The difference between these two numbers, 0.26, represents the additional IQ correlation that identical twins share because of their extra 50% of shared genes, so doubling the number gives us 52% heritability.

IQ tests emphasize spatial skills, like map-reading and mental rotation, which show the greatest dependence on genes, and verbal skills, which are not far behind. Mental speed appears somewhat less heritable, and memory skills are the least heritable of the mental abilities that behavioral geneticists have assessed.

Intelligence actually grows more heritable with age. About 15% of the variance in babies’ IQs can be explained by genes. The figure rises to 40% by the early school years, 50% by adolescence, and a few additional points by adulthood. By adolescence, adoptees’ IQs come to resemble that of their biological parents much more than their adoptive parents’.

Since the beginning of IQ testing, each generation has scored higher than the last. American IQs are rising about 8 points per generation. The average American today scores as well as the top 2% a century ago. IQ gains are considerably greater for visual-spatial skills than for verbal ones, suggesting that the increase may be largely attributable to the explosion of visual media.

What’s Going On in There?, by Lise Eliot, Ph.D.

Money won’t buy happiness, but if you’re a man, money will probably play a role in how successful you are with women, as the psychologist David M. Buss makes plain in The Evolution of Desire. In one experiment, women were shown photographs of the same men, sometimes dressed in fast-food uniforms and at other times in classy business attire. When the men wore clothes that screamed “money,” they were rated as more attractive. Women’s incomes seem to matter less to men, who are much more concerned with a mate’s looks.

In general, more income and education mean a longer life. So does increased social status, which is also associated with money. In the so-called Whitehall studies of British civil servants, for example, researchers have found that an individual’s occupational grade was strongly correlated to longevity: the higher the grade, the longer the life.

Money can help with everything except your natural disposition but even the crankiest among us will consider ourselves better off with a more desirable spouse, better schools for our children, higher status and surer access to health care. There is also evidence that happiness comes as much from giving as receiving, and dollars can help here — earning more means that you can give more.

“Dear Graduates: Money Is a Means,” by Daniel Akst

A paper written by Dr Mario Mendez, a neurologist at the University of California, describes a patient who, in his fifties, had suffered a stroke that crippled his understanding of language. So, for example, the patient could not understand a simple request such as “touch your chin.” But after his stroke, the patient, who had been unmusical, discovered a passion for music, and the attending of concerts became his main activity. He would often answer Dr Mendez’s questions by breaking into song.

The greatest determinant of musicality is pitch: the better your pitch, the more likely you are to enjoy music. And perfect pitch (the ability to sing a note to order) is rare among adults — perhaps only 1 in 10,000 has it. Yet perfect pitch is common among the autistic.

And musical savants are not rare. In his book Musical Savants: Exceptional Skill in the Mentally Retarded, Leon Miller, of the University of Illinois, described 13 people who were indeed mentally retarded. Typically, their IQs and social skills were so rudimentary that they could not speak or dress themselves. But musically they were gifted, not only playing well but also composing creatively. And, typically, they had perfect pitch.

When we talk to babies, we instinctively use a cootchy-coo language that is essentially musical. We do so because babies understand pitch and the other elements of song. Dr Anne Fernald, a psychologist at Stanford University, has shown that babies respond appropriately, with smiles or frowns, to praise or admonishment when delivered in baby talk, even if the language is foreign. “What a good girl!,” delivered in French, provokes a happy smile in an English nursery.

Studies on mothers have shown that, in the privacy of their homes, 100 per cent of mothers — even the unmusical ones — sing to their babies because singing so effectively influences babies’ moods.

And the babies respond because, as Jenny Saffron of the University of Rochester, New York, has shown, we humans are born with perfect pitch. But babies lose their perfect pitch when language kicks in. We can see, therefore, how musical savants might arise, because intelligence and language are separate from music.

Songbirds have perfect pitch and, despite their tiny brains, they can be good composers, employing many of the repetitions that characterise human music such as refrains, rhymes and reprises. So the winter wren will, from the adults around him, learn a set of songs that he will then dissect into shorter phrases to rearrange into thousands of different songs. The chocolate-backed kingfisher moves up and down its own scale, while the music wren sings with a near-perfect scale.

In The Singing Neanderthals, Steven Mithen, an archaeologist at Reading University, argues that Neanderthals sang but did not speak, and that it was Homo sapiens’s development of language about 100-200 thousand years ago that allowed us to create the superior skills that, in their turn, allowed us to drive the Neanderthals into extinction.

Geoffrey Miller, of the University of New Mexico, has examined the gender and age of the singers of 6,000 recent jazz, rock and classical albums, and showed that 90 per cent of commercial songs are produced by males, and that their peak age of production is 30 (the peak age for male success in coition, apparently).

“Sorry, Maestro Barenboim. Music is for idiots and Neanderthals,” by Terence Kealey, The Times

A group of scientists led by James Roney of the University of California, Santa Barbara has discovered that women can tell who is and is not fond of children just by looking at their faces.

Their 39 male subjects, selected from a variety of ethnic backgrounds, were shown 20 pairs of pictures, each depicting an adult and an infant. They were asked to signify their preference for either the adult or the child. Some reported no interest in the child at all. The rest expressed a range of interest, including a few who always preferred the pictures of infants. The men also provided saliva swabs to assess their testosterone levels. The researchers then took digital photographs of the men and doctored the images so that their hairstyles were obscured, and could not affect the judgments of the female subjects.

These were a group of 29 women, from equally diverse backgrounds, who were shown the photographs. They were asked to rate the men according to whether they thought the men liked children, and whether those men appeared masculine and physically attractive. They were also asked to say which men they preferred for short-term and which for long-term relationships. The results (pdf file here), which have just been published in the Proceedings of the Royal Society, confirm that women are very good at reading faces.

When asked to rate the men’s masculinity, the women agreed on who was top and who was bottom, and their rankings correlated with the testosterone levels from the swabs.

The features that research has suggested denote high testosterone levels include a prominent jaw and a heavy beard. 

When asked to rate the men’s liking of children from the photographs, the women ranked them in the same order as the researchers had done from the interest the men themselves had shown in pictures of infants.

When asked with whom they would prefer to have a short-term relationship, women tended to pick the high-testosterone males. This makes sense from an evolutionary point of view, since testosterone suppresses the immune system. An excess of testosterone suggests that an individual must have particularly disease-resistant genes in order to compensate. These make desirable partners for a woman’s own genes in her children. The problem with testosterone-fuelled males is that they are less likely to remain faithful to their partners.  

By contrast, men who show an interest in children are also likely to make good partners, because they will care for their offspring. The study showed that women prefer these men for long-term relationships.

Surprisingly, some men were perceived both as masculine and as interested in children

After the study was completed, five graduate students were asked to rate on a scale of 1 to 7 whether the men looked angry or happy. Though the men were instructed to have a neutral look on their faces when photographed, some apparently looked happier than others. The men who picked more infants in that test had a happier or more content look on their face.

“Oochy woochy coochy coo,” The Economist

“Women Get Paternal Clues in Men’s Faces,” CBS News

Alvin and Heidi Toffler’s new book, Revolutionary Wealth, argues that we, as a species, have been getting better at producing wealth. If we hadn’t, the planet would not now be able to support nearly 6.5 billion of us. And, for better or worse, we wouldn’t have more overweight people than undernourished people on earth — as we do.

Life expectancy at birth in the world, including the “poor world,” increased 42 percent over the past 50 years.

The titular wealth the Tofflers speak of comes from substituting ever-more-refined knowledge for the traditional factors of industrial production — land, labor and capital. The United States is producing more stuff than ever with fewer workers. Only 20 percent of the work force is now in the manufacturing sector, while some 56 percent (and growing) is engaged in “knowledge work” — managerial, financial, sales-related, clerical and professional tasks. Even activities like agriculture have gone high-tech, through biotechnology and increasingly sophisticated use of global-positioning satellites to customize irrigation and fertilization down to the individual acre.

Knowledge-based wealth is revolutionary not just because it gets more output from fewer inputs. Unlike such physical resources as oil, knowledge can be shared by an infinite number of people, and its value and benefits are generally increased by wider circulation.

This schema helps to explain why air quality has improved in American cities over the past 30 years and why American culture has become remarkably more accepting of alternative lifestyles.

“The Future Is Now,” by Nick Gillespie

As things now stand, the European population is set to decline over the next 50 years. Couples are having fewer children, having them later or not having them at all. While the populations of Asia, Africa and America will grow, Europe will shrink.

In the Fifties and Sixties, the average manual worker worked 48 years, 48 weeks per year and 48 hours (including overtime). He retired at 65. Women worked with more interruptions, fewer years and fewer hours, and retired at 60. Men and women did not live many years beyond retirement.

Now we all live longer beyond retirement. Men’s working patterns resemble women’s more and more - interrupted working with the need to change jobs, to train and develop new skills. Our savings while in work are insufficient to finance our spending in retirement.

Pensions of the presently retired are paid out of the savings of the currently working. If the cohort working is large relative to those retired, pensions will pose no problem. But Europe’s population is not growing very fast.

Some countries such as Italy face the prospect of a shrinking population. By 2050, Europe’s population is predicted to be smaller than it is now if we rely on reproduction alone. With a shrinking population, Europe will not be able to fund its pensions without taking drastic steps.

The Department of Economic and Social Affairs of the UN calculated some years ago that Europe needs to import between 150 to 200 million extra people over the next 20 to 30 years if the age structure of the population is to have enough people of a working age.

We all speak of globalisation and the free movement of capital across borders. Trade is also growing with fewer restrictions and lower tariffs. But nations states everywhere jealously guard their frontiers and discriminate between their citizens and foreigners.

This was not the case in the 19th century when we had a similar phase of globalisation. Then people as well as commodities and capital moved freely. One third of Europe’s population moved across to North America and thus improved Europe’s chances of development immensely. People moved from India to the Caribbean, eastern and southern Africa, to South-east Asia and the South Pacific islands. Chinese people moved across the Pacific to the Americas, to Australia (till the Whites Only policy stopped their movements in 1900) and to South-east Asia. It was only in the 20th century, after the First World War, that the labelling of citizens and foreigners became general.

If we want to be generous in allowing people to migrate to us, we cannot at the same time be generous in their entitlements. They would have to work and would not be able to claim unemployment benefits till after they had qualified as citizens.

“Let People Come Here from All Over the World,” by Meghnad Desai

Hernando de Soto and his research team collected facts and figures, block by block and farm by farm in Asia, Africa, the Middle East, and Latin America. They found that the value of savings among the poor is immense - forty times all the foreign aid received throughout the world since 1945. In Egypt, for instance, the wealth that the poor have accumulated is worth fifty-five times as much as the sum of all direct foreign investment ever recorded there, including the Suez Canal and the Aswan Dam. In Haiti, the poorest nation in Latin America, the total assets of the poor are more than one hundred fifty times greater than all the foreign investment received since Haiti’s independence from France in 1804. If the United States were to hike its foreign-aid budget to the level recommended by the United Nations — 0.7 percent of national income — it would take the richest country on earth more than 150 years to transfer to the world’s poor resources equal to those they already possess.

But they hold these resources in defective forms: houses built on land whose ownership rights are not adequately recorded, unincorporated businesses with undefined liability, industries located where financiers and investors cannot see them. Because the rights to these possessions are not adequately documented, these assets cannot readily be turned into capital, cannot be traded outside of narrow local circles where people know and trust each other, cannot be used as collateral for a loan, and cannot be used as a share against an investment.

In the West, by contrast, every parcel of land, every building, every piece of equipment, or store of inventories is represented in a property document that is the visible sign of a vast hidden process that connects all these assets to the rest of the economy. They can be used as collateral for credit. The single most important source of funds for new businesses in the United States is a mortgage on the entrepreneur’s house. These assets can also provide a link to the owner’s credit history, an accountable address for the collection of debts and taxes, the basis for the creation of reliable and universal public utilities, and a foundation for the creation of securities (like mortgage-backed bonds) that can then be rediscounted and sold in secondary markets.

It is the unavailability of these essential representations that explains why people who have adapted every other Western invention, from the paper clip to the nuclear reactor, have not been able to produce sufficient capital to make their domestic capitalism work.

Westerners take this mechanism so completely for granted that they have lost all awareness of its existence. Western politicians once faced the same dramatic challenges that leaders of the developing and former communist countries are facing today. But their successors have lost contact with the days when the pioneers who opened the American West were undercapitalized because they seldom possessed title to the lands they settled and the goods they owned, when Adam Smith did his shopping in black markets and English street urchins plucked pennies cast by laughing tourists into the mud banks of the Thames, when Jean-Baptiste Colbert’s technocrats executed 16,000 small entrepreneurs whose only crime was manufacturing and importing cotton cloth in violation of France’s industrial codes. Americans and Europeans established widespread formal property law and invented the conversion process in that law that allowed them to create capital. This was when capitalism ceased being a private club and became a popular culture.

“The Mystery of Capital” by Hernando de Soto

It is likely that everyone is born with perfect pitch and then loses it as they grow older.

This theory has been put forward by psychologists at the University of Wisconsin-Madison, who think perfect, or absolute, pitch — the ability to precisely recognise musical notes — helps babies to learn to speak.

Once this task is achieved, perfect pitch is lost — unless it is deliberately cultivated in some way, either by learning a musical instrument or by speaking a language that conveys subtle meaning with different tones.

As part of their studies, the researchers played adults and eight-month-old babies long sequences of musical notes.

They found that if they changed the sequence only slightly, the adults could not tell the difference — but the babies could.

They could tell this because it was well documented that babies got bored if they heard the same thing too often — their attentions strayed.

In the experiments, Professor Jenny Saffran and colleagues found that if they played the babies a slightly new series of notes after repeating the old sequence a few times, the babies would recognise this and give the music their full attention again.

“Perfect Pitch May Help Babies Speak,” by Jonathan Amos

Twenty years ago, a political philosopher named James Flynn uncovered a curious fact. Americans — at least, as measured by I.Q. tests — were getting smarter. This fact had been obscured for years, because the people who give I.Q. tests continually recalibrate the scoring system to keep the average at 100. But if you took out the recalibration, Flynn found, I.Q. scores showed a steady upward trajectory, rising by about three points per decade, which means that a person whose I.Q. placed him in the top ten per cent of the American population in 1920 would today fall in the bottom third. Some of that effect, no doubt, is a simple by-product of economic progress: in the surge of prosperity during the middle part of the last century, people in the West became better fed, better educated, and more familiar with things like I.Q. tests. But, even as that wave of change has subsided, test scores have continued to rise — not just in America but all over the developed world. What’s more, the increases have not been confined to children who go to enriched day-care centers and private schools. The middle part of the curve — the people who have supposedly been suffering from a deteriorating public-school system and a steady diet of lowest-common-denominator television and mindless pop music — has increased just as much. In Everything Bad Is Good for You, Steven Johnson proposes that what is making us smarter is precisely what we thought was making us dumber: popular culture.

Television is very different now from what it was thirty years ago. A typical episode of “Starsky and Hutch,” in the nineteen-seventies, followed an essentially linear path: two characters, engaged in a single story line, moving toward a decisive conclusion. To watch an episode of “Dallas” today is to be stunned by its glacial pace — by the arduous attempts to establish social relationships, by the excruciating simplicity of the plotline, by how obvious it was. A single episode of “The Sopranos,” by contrast, might follow five narrative threads, involving a dozen characters who weave in and out of the plot. The extraordinary amount of money now being made in the television aftermarket — DVD sales and syndication — means that the creators of television shows now have an incentive to make programming that can sustain two or three or four viewings.

Twenty years ago, video games like Tetris or Pac-Man were simple exercises in motor coördination and pattern recognition. Johnson points out that one of the “walk-throughs” for “Grand Theft Auto III” — that is, the informal guides that break down the games and help players navigate their complexities — is fifty-three thousand words long, about the length of his book.

Video games don’t have a set of unambiguous rules that have to be learned and then followed during the course of play. We have to figure out what to do. These games withhold critical information from the player. Players have to explore and sort through hypotheses in order to make sense of the game’s environment, which is why a modern video game can take forty hours to complete.

Players are required to manage a dizzying array of information and options. The game presents the player with a series of puzzles, and you can’t succeed at the game simply by solving the puzzles one at a time. You have to craft a longer-term strategy, in order to juggle and coördinate competing interests.

Johnson imagines what cultural critics might have said had video games been invented hundreds of years ago, and only recently had something called the book been marketed aggressively to children: Reading books chronically understimulates the senses. Unlike the longstanding tradition of gameplaying — which engages the child in a vivid, three-dimensional world filled with moving images and musical sound-scapes, navigated and controlled with complex muscular movements — books are simply a barren string of words on the page. Books are also tragically isolating. While games have for many years engaged the young in complex social relationships with their peers, building and exploring worlds together, books force the child to sequester him or herself in a quiet space, shut off from interaction with other children. But perhaps the most dangerous property of these books is the fact that they follow a fixed linear path. You can’t control their narratives in any fashion — you simply sit back and have the story dictated to you. This risks instilling a general passivity in our children, making them feel as though they’re powerless to change their circumstances. Reading is not an active, participatory process; it’s a submissive one.

When you read a biology textbook, the content of what you read is what matters. When you play a video game, the value is in how it makes you think.

Being “smart” involves the kind of fluid problem solving that matters in things like video games and I.Q. tests, but also the kind of crystallized knowledge that comes from explicit learning. When it comes to the latter kind of intelligence, it is not clear at all what kind of progress we are making, as anyone who has read, say, the Gettysburg Address alongside any presidential speech from the past twenty years can attest.

“Brain Candy,” by Malcolm Gladwell

Diana Deutsch, professor of psychology at the University of San Diego, tested 88 students for perfect pitch ability at China’s Central Conservatory of Music in Beijing. An individual has perfect pitch when he or she can name or produce a musical note without benefit of a reference note. All of the Chinese students spoke the tone language Mandarin.

Tone languages, such as Mandarin, Cantonese, Thai and Vietnamese, require that individuals adjust tone and pitch to indicate a word’s meaning. For example, in Mandarin, the word “ma” variously can mean “mother,” “hemp,” “horse” or a reproach, depending on the speaker’s tone.

Deutsch and her team next tested perfect pitch amongst 115 English-speaking students at the Eastman School of Music in Rochester, N.Y. For both groups of students, the test involved identifying by name 36 piano notes spanning a three-octave range, and filling out a questionnaire that included the age their musical training commenced.

While early music lessons improved the likelihood of a student having perfect pitch, the language of the students had a much stronger impact on pitch ability. For students who began musical training between the ages of four and five, 74 percent of the Mandarin speakers passed the perfect pitch test versus 14 percent of the English speakers.

“My hunch is that the differences we found here are based on early exposure to tone language on the part of Mandarin speakers —- or put differently, that the rarity of this ability in non-tone language speakers (less than one in 10,000) is due to their lack of early experience with associating pitches with meaningful words,” Deutsch told Discovery News shortly after her ASA presentation.

She believes, however, that it likely is possible for all young children to learn perfect pitch when they are first developing their language skills.

Deutsch said, “I believe it would be worthwhile for parents to give their babies the opportunity to bang on a synthesizer keyboard that they could just have lying around on the floor — but they should label the notes with letter names, or color-code the 12 notes within the octave. This would be a simple, inexpensive, and harmless thing to do, that would be fun for the baby and might possibly have dramatic results.”

Aniruddh Patel, the Esther J. Burnham Fellow at San Diego’s The Neurosciences Institute and author of the second study, was impressed by Deutsch’s findings.

For Patel’s own study, he charted the patterns of pace and stress, as well as the intonation, of spoken English and French. He then used a similar technique to chart the rhythm and pitch of classical music written by famous English and French composers, such as Sir Edward Elgar and Claude Debussy.

Patel discovered that the native language spoken by the composers was mirrored in the stress and intonation of their music.

“The techniques we present can be applied to the language and music of any culture,” Patel said, and added that even jazz seems to reflect the composer’s language. Pop, however, remains a mystery.

Patel said, “Pop may involve a lot more borrowing of musical styles from other cultures, which would blur any differences.”

“Study: Language Determines Music Skills,” by Jennifer Viegas