Cover; June 2004; Scientific American Magazine; by Staff Editor; 1 Page(s)

Table of Contents; June 2004; Scientific American Magazine; by Staff Editor; 2 Page(s)

SA Perspectives: Stem Cells: A Way Forward; June 2004; Scientific American Magazine; by Staff Editor; 1 Page(s)

Korean investigators have extracted stem cells from a cloned human embryo. A Harvard biologist has developed 17 lines of human embryonic stem cells that he is making freely available to the scientific community. A ballot drive in California seeks to raise $3 billion for similar science [see "The Stem Cell Challenge," by Robert Lanza and Nadia Rosenthal, on page 92]. Unquestionably, research on human embryonic stem cells is moving forward.

A conspicuously missing partner in that progress is the U.S. government. In August 2001 President George W. Bush allowed the use of federal funds for work on embryonic stem cells but only on those from sanctioned samples. Those cells lines, far fewer than were promised, have many limitations and may be unsuitable for future therapeutic applications.

How to Contact Us and On the Web; June 2004; Scientific American Magazine; by Staff Editor; 1 Page(s)

Letters to the Editors; June 2004; Scientific American Magazine; by Staff Editor; 2 Page(s)

AS THE OLD maxim goes, the proof that an article about a contentious subject is balanced is that both sides think it favored the other guy. Consider Richard Rosenfeld's "The Case of the Unsolved Crime Decline" [February]. Roy Jaruk, writing via e-mail, criticized the article's stance against laws that permit carrying concealed weapons for self-protection against criminals: Rosenfeld "claims that 'the case for "more guns, less crime" remains unproved." Perhaps it does in the minds of ivory-tower liberals." A. C. Doyle of Boston chided the magazine, too: "Rosenfeld may back the NRA's push to allow concealed guns in schools and churches, but it is not based on any sort of rigorous research, nor should you try to conceal your own views against gun control under the guise of impartial reporting." A fair and balanced look at other February letters follows.

How sad! A professor of criminology building an argument on a mistaken assumption that there are national crime rates and national solutions ["The Case of the Unsolved Crime Decline," by Richard Rosenfeld]. Crime is not nationalit, like politics, is local. New York City accounted for about 60 percent of the nation's homicide reduction in 1994 and 30 percent in 1995; similar effects occurred for robbery. Surely such numbers would skew any "national" trend.

50, 100 and 150 Years Ago; June 2004; Scientific American Magazine; by Staff Editor; 1 Page(s)

VACCINE FEAR - "After several weeks of confusion about the safety of the new poliomyelitis vaccine, mass tests got under way last month. Walter Winchell had told his radio audience that the vaccine 'may be a killer' because one batch had been found with live virus. The National Foundation for Infantile Paralysis, which is conducting and financing the test, hastened to make clear that each batch of vaccine was subjected to a three-laboratory check. The foundation pointed out that Jonas Salk, who developed the vaccine, had given the commercial preparation to more than 4,000 Pittsburgh children, none of whom showed any untoward effects."

SILICON SOLAR CELL - "A little wafer of adulterated silicon which converts sunlight directly into electrical energy was unveiled last month by Bell Telephone Laboratories. This solar battery is an outgrowth of transistor research. It works at an efficiency of 6 per cent. Bell scientists believe that the figure can be raised to 10 per cent. The device is not likely to replace large-scale power plants - a 30,000 kilowatt battery would cover some 100 acres - but the company expects it to be useful as a small power source for such applications as rural telephone systems."

Diving for Dead Wood; June 2004; Scientific American Magazine; by Sarah Simpson; 2 Page(s)

Tangled, ghostly limbs barely tickle the water's surface from below. Elaborate roots grip lakebeds, though perhaps not as strongly as they did the forest floor. Such is the fate of millions of acres of prime timber - flooded in the wake of hydroelectric dams, sacrificed to make electricity.

Most of these drowned trees were left for dead long ago. But in western Canada, some of them are experiencing a reincarnation of sorts. Chris Godsall, a sustainable forestry specialist based in Victoria, B.C., has cut more than 1,000 submerged trees since January, a feat made possible by his invention of the world's first logging submarine.

Homo carnivorous; June 2004; Scientific American Magazine; by Gary Stix; 2 Page(s)

The organization People for the Ethical Treatment of Animals entreats individuals to adopt vegetarianism as the "healthiest and most humane choice for animals, people and the planet." But don't stow away those carving knives just yet. Our carnivorous proclivities go back a long way - and our ability to cope with the drawbacks of meat eating (elevated cholesterol, parasites and infections) may derive from certain genes.

Meat eating, in fact, may have a lot to do with the sapiens tag that follows Homo. For our ancestors, meat supplied a more concentrated package of calories and nutrients than weeds and berries. Not being the biggest and strongest members of the food chain, however, Homo carnivorous also required more cunning and wile to bring down that mastodon. One theory holds that a bigger brain and a longer period of nurturing and apprenticeship had to evolve to master the hunt. These changes also selected for extended life span, as prehistoric hunters were not thought to have achieved mastery of their skills until comparatively late in life.

Eye on the Junk; June 2004; Scientific American Magazine; by Phil Scott; 1 Page(s)

Last November cosmonaut Alexander Kaleri was onboard the International Space Station (ISS) when he heard a loud bang. Kaleri didn't believe the sound was from balky equipment; rather it seemed to originate from outside. This past April the ISS crew reported hearing a similar clang. NASA has doubts whether the sounds really came from space junk hitting the station. But the noises have engineers paying renewed attention to the threat of orbital debris, which can act as missiles.

Space junk dates back to the beginning of the Space Age. The oldest known hunk is Vanguard 1, launched by the U.S. on March 17, 1958. Forty-six years later the number of known orbital objects at least 10 centimeters wide has grown to nearly 11,000, and only several hundred of those are operational satellites, according to the U.S. Space Command in Cheyenne Mountain, Colo., which monitors these objects. Material in the lowest altitudes flies at around seven to eight kilometers a second. At that velocity, debris just a few millimeters wide would have the impact of a bowling ball moving at highway speeds.

Sitcoms on the Brain; June 2004; Scientific American Magazine; by Marina Krakovsky; 1 Page(s)

What do you get when you cross a television comedy with a brain scanner? A team led by Joseph Moran and William Kelley at Dartmouth College's Center for Cognitive Neuroscience tried to find out. The researchers used functional magnetic resonance imaging (fMRI) on subjects watching episodes of either Seinfeld or The Simpsons. The resulting scans showed that "getting" a joke occurs in specific brain regions different from those involved in finding it funny.

This dissociation between the cognitive and emotional parts of humor supports the scant previous research on humor's neural underpinnings, but the current study is the first to test the kind of humor people often experience in real life. "The idea of using sitcoms is very nice," comments Vinod Goel, a psychologist at York University in Toronto, noting that they are funnier than the puns and lawyer jokes he has used in his neuroimaging research.

Power-Thrify PCs; June 2004; Scientific American Magazine; by Steven Ashley; 2 Page(s)

Putting a personal computer to sleep is typically the only means for users to conserve electricity, besides frequent, often inconvenient, shutdowns. Now a new focus of energy savings for the PC has emerged - its power supply.

When a PC is operating, its power supply typically converts only 60 to 70 percent of the 120-volt AC power into the 12-, 5- and 3.3-volt DC juice the internal system components need. The rest is mostly lost to heat. Each of the estimated 205 million PCs in the U.S. consumes an average of about 300 kilowatt-hours of power annually, and that figure does not include the monitor's energy usage. Making PC power supplies 80 percent efficient, researchers say, could shave U.S. energy use by 1 to 2 percent and pare $1 billion or more from the nation's yearly electric bills while cutting emissions from generating plants significantly.

The 17-Year Itch; June 2004; Scientific American Magazine; by Tabitha M. Powledge; 2 Page(s)

From late May through June, Brood X of the periodical cicadas will emerge from the ground, having spent the past 17 years as nymphs feeding off tree roots. After digging their way out and molting into adults, billions of the big, clumsy, red-eyed insects will sing their earsplitting love songs. Last seen in 1987, the brood will provide a prodigious if brief feast for birds, along with an incomparable opportunity for researchers. Fascinated naturalists have been writing about periodical cicadas for four centuries. But much remains unknown about the insects' periods or what triggers their synchronized appearances.

Brood X is perhaps the largest and best studied of the approximately 15 broods of periodical cicadas (researchers dispute the exact number). A brood emerges somewhere east of the Great Plains almost every spring. Worldwide, investigators have identified some 3,000 cicada species but know the life cycle for only a dozen or so. William Bradford, governor of the Plymouth Colony, first described periodical cicadas in 1633, although Native Americans probably knew of the creatures before then. The 17-year life cycle was firmly established less than a century later; by the mid-19th century, naturalists had recognized 13-year cicadas.

By the Numbers: Civic Culture; June 2004; Scientific American Magazine; by Rodger Doyle; 1 Page(s)

Recent decades have seen a revival of interest in civic culture, sometimes called social capital or civic republicanism. As the term is generally used, it includes a high level of trust and tolerance, an egalitarian spirit, volunteerism, an interest in keeping informed, and participation in public affairs.

Political scientists Tom W. Rice of the University of Iowa and Jan L. Feldman of the University of Vermont have measured civic culture among ancestry groups in the U.S. They find that Americans of Scandinavian and British descent have the highest levels of civic culture, with those of French, Irish, German and Dutch descent having somewhat lower levels; those of Italian and Spanish descent have decidedly lower levels. (Spanish ancestry as measured in the study for the most part excludes Hispanic-Americans.) Furthermore, they conclude that these ethnic cultures are a continuation of the cultures in the country of origin. Thus, the 17th-century Puritan culture of England was transplanted to New England, and Minnesota saw the merging of 19th-century Swedish and German cultures.

News Scan Briefs; June 2004; Scientific American Magazine; by JR Minkel, Philip Yam; 3 Page(s)

If noise, injury or a thin atmosphere ever gets in the way of conversations between future astronauts, a NASA technology that recognizes unspoken words may come in handy. The tongue and vocal cords may not move when speaking silently, but they still receive speech signals. To pick up those signals, Chuck Jorgensen of the NASA Ames Research Center placed button-size sensors under the chin and on the neck of three subjects. A computer program recorded electrical activity whenever it rose above background noise and learned to associate the signals from an individual speaker with one of about 20 different words nearly 90 percent successfully, Jorgensen claims. By silently mouthing numbers, subjects browsed the Web without a keyboard. Hazmat crews, divers and the handicapped may benefit from subvocal speech recognition, says Jorgensen, whose findings were announced by NASA in March.

Preschool children who have difficulty sleeping may be more likely to drink alcohol and abuse other drugs later in life. University of Michigan at Ann Arbor researchers followed a group of 257 boys, between the ages of three and five, for 10 years. Boys who had habitual problems falling asleep or experienced fatigue during the day were about twice as likely as healthy sleepers to drink, smoke tobacco and use illicit drugs in their teens. The link remained even when the investigators controlled for other substance-abuse predictors, such as depression, attention deficits and parental alcoholism. Lack of sleep may cause a chemical imbalance, or sleep disorders and drug addiction may share a common brain pathway, says clinical psychologist Robert Zucker, senior author of the report, which appears in the April issue of Alcoholism: Clinical and Experimental Research. The risk isn't particularly huge, he notes, but improving early sleep habits could avoid future pitfalls.

Innovations: A Confederacy of Smarts; June 2004; Scientific American Magazine; by Gary Stix; 4 Page(s)

Thousands of Microsoft product developers - a sea of tieless shirts, dress pants and jeans - have descended on a nondescript building on the company's main campus in Redmond, Wash., one drizzly day in early March. Inside, rows of booths display the latest intellectual output from many of the 700 scientists who make up the software maker's research division. At one booth, there is a microphone that eliminates background noise. At another is software that converts a video image of a face into a graphic animation. Moving along, the visitor comes across a digital camera worn on the body of an exhibitor that snaps a frame every time the camera senses a change in temperature or light, creating a comprehensive record of a person's entire waking life. The annual event, called TechFest, is a means of ensuring that product developers stay aware of what the research side is doing.

The displays demonstrate a mix of ingenuity and cuteness typical of academic computer science departments. The Media Lab at the Massachusetts Institute of Technology immediately comes to mind. More startling than the displays themselves are some of the individuals walking the floor at the exhibition. Among them are engineers, mathematicians and programmers, some of whose ponytails are now graying, who would be shoo-ins for a Computer Science Hall of Fame. Meet C. Gordon Bell, an inventor of the minicomputer. Or James Kajiya, creator of some of the key mathematics underlying computer graphics rendering and winner of an Academy Award for technical achievement. Then there is James Gray, a giant in databases. These legendary figures have not come for a casual visit. During the past 13 years, using its enormous cash stockpiles, Microsoft has hired scores of these techno-wizards from universities and competitors to create one of the largest concentrations of talent the field has ever seen.

Staking Claims: The Silent Revolution; June 2004; Scientific American Magazine; by Gary Stix; 1 Page(s)

Ex parte Allen. The doctrine of equivalents. Methods of doing business. Interferences. The First Inventor Defense Act. Reduction to practice. The mental steps doctrine. Disclosure under section 102(e). Derivation under section 102(f). The recapture rule. Laches and estoppel. Graver Tank v. Linde Air Products Co. Jepson claims.

The patent bar is a priesthood with its own secret dialect, intelligible only to initiates. Two economists - Adam B. Jaffe of Brandeis University and Josh Lerner of Harvard Business School - have now undertaken to translate for the rest of us the inner workings of the patent process and then to dissect what plagues it. Innovation and Its Discontents: How Our Broken Patent System Is Endangering Innovation and Progress and What to Do about It is to be published by Princeton University Press in October. The book describes how two seemingly well-meaning changes made by the U.S. Congress have engendered the current crisis.

Skeptic: Death by Theory; June 2004; Scientific American Magazine; by Michael Shermer; 1 Page(s)

In April 2000, 10-year-old Candace Newmaker began treatment for attachment disorder. Her adoptive mother of four years, Jeane Newmaker, was having trouble handling what she considered to be Candace's disciplinary problems. She sought help from a therapist affiliated with the Association for Treatment and Training in the Attachment of Children (www.ATTACh.org) and was told that Candace needed attachment therapy (AT), based on the theory that if a normal attachment is not formed during the first two years, attachment can be done later.

According to the theory, the child must be subjected to physical "confrontation" and "restraint" to release repressed abandonment anger. The process is repeated until the child is exhausted and emotionally reduced to an "infantile" state. Then the parents cradle, rock and bottle-feed him, implementing an "attachment."

Insights: A Transparent Enigma; June 2004; Scientific American Magazine; by Madhusree Mukerjee; 2 Page(s)

At 7 a.m. in a nondescript apartment in Hollywood, Calif., Tito Mukhopadhyay is hunched over his breakfast bowl, spooning milk and cereal into his mouth. His eyes flit around and his hand shakes. When he is finished, his mother, Soma Mukhopadhyay, pulls him off the chair and manhandles him into the shower, dashing in from time to time when he yells for assistance. Finally Tito emerges, dressed, to bend over Soma's tiny frame so she can comb his thick black hair. Abruptly he charges out the door and half-walks, half-runs down the hallways until he is outside. Golden sunshine on his face, he flaps and spins his hands with absorption.

Later I ask him: "Would you like to be normal?" In rough but legible script, he scrawls: "Why should I be Dick and not Tito?"

Working Knowledge: Deep Silence; June 2004; Scientific American Magazine; by Mark Fischetti; 2 Page(s)

The USS Miami nuclear submarine is 362 feet long, weighs 395 tons and is thrust by 35,000-horsepower engines. Yet the sound it radiates into the sea is little more than the hum of a kitchen refrigerator.

The ocean can be a noisy place: collapsing waves, rain, ships and marine animals (particularly snapping shrimp!) create quite a cacophony. The audio signatures generated by submarine machinery and propellers are distinct, however, and their propagation must be reduced profoundly so a sub can disappear into the background noise. Enemy forces are constantly listening with floating sonobuoys, sonar mines, passive arrays towed by ships and subs, as well as active sonar from those vessels.

Saturn at Last!; June 2004; Scientific American Magazine; by Jonathan I. Lunine; 8 Page(s)

Early in the morning of October 15, 1997, standing in the dark on the edge of an alligator-infested inlet near Cape Canaveral, Fla., I watched with thousands of others as a tiny flame appeared beneath a rocket illuminated by floodlights on a launchpad several miles away. Only the booster's fiery tail was visible as the rocket ascended through a cumulus cloud and then arced over the ocean, headed for space. The most sophisticated robotic spacecraft ever built, the Cassini orbiter and the attached Huygens probe, were poised atop the launch vehicle, and seven years of interplanetary voyaging lay ahead. I had begun my involvement in the planning of this mission as a graduate student, and I would have to wait until the middle of my scientific career to see its culmination: the first prolonged exploration of the Saturnian system.

This July the Cassini-Huygens spacecraft is expected to go into orbit around the solar system's second-largest planet. Researchers have been eagerly awaiting this day ever since the flyby missions - Pioneer 11 and Voyagers 1 and 2 - piqued their interest in Saturn more than 20 years ago. Although the planet is smaller than Jupiter and its surface is much less dramatic in appearance, Saturn may hold vital clues to the long-term evolution of all the gas-giant planets. Saturn's retinue of moons includes 30 icy satellites and one planet-size body, Titan, which has a dense atmosphere that fascinates scientists because it could reveal how life arose on Earth. Researchers also wish to discover how Saturn's rings formed and how the planet's powerful magnetic field affects the icy moons and the upper atmosphere of Titan.

Nanotechnology and the Double Helix; June 2004; Scientific American Magazine; by Nadrian C. Seeman; 10 Page(s)

The year 2003 witnessed the 50th anniversary of the discovery of DNA's double-helix structure by James D. Watson and Francis H. Crick. Their discovery reduced genetics to chemistry and laid the foundations for the next half a century of biology. Today thousands of researchers are hard at work deciphering the myriad ways that genes control the development and functioning of organisms. All those genes are written in the medium that is DNA.

Yet this extraordinary molecule has other uses in addition to those of biochemistry. By employing the techniques of modern biotechnology, we can make long DNA molecules with a sequence of building blocks chosen at will. That ability opens the door to new paths not taken by nature when life evolved. In 1994, for example, Leonard M. Adleman of the University of Southern California demonstrated how DNA can be used as a computational device [see "Computing with DNA," by Leonard M. Adleman; Scientific American, August 1998]. In this article I will discuss another nonbiological use of DNA: the building of structures and devices whose essential elements and mechanisms range from around one to 100 nanometers in size - in a word, nanotechnology.

Lessons from the Wolf; June 2004; Scientific American Magazine; by Jim Robbins; 6 Page(s)

Several scrawny cottonwood trees do not usually generate much excitement in the world of ecology. But on a wind-whipped August afternoon in Yellowstone National Park's Lamar Valley, William J. Ripple, a professor of botany at Oregon State University, stands next to a 12-foot-high cottonwood tree and is quietly ecstatic. "You can see the terminal bud scars," the bespectacled Ripple says, bending the limber tree over to show lines that mark a year's growth of a foot or more on the broom-handle-size trunk. "You can see that elk haven't browsed it this year, didn't browse it last year and, in fact, haven't browsed it since 1998.

Ripple gestures at the sprawling mountain valley around us and points out that although numerous other cottonwoods dot the landscape, this knot of saplings comprises the only young ones - the rest of this part of the Lamar is a geriatric ward for trees. The stately specimens that grow in the valley bottom are 70 to 100 years old, and not a newcomer is in sight to take their place. On the hillside, aspen trees present a similar picture. Groves of elderly aspen tremble in the wind, but no sprouts push up in the understory.

Smart Sensors to Network the World; June 2004; Scientific American Magazine; by David E. Culler and Hans Mulder; 8 Page(s)

Today we coddle our computers. They are fragile and expensive, so each typically belongs to an owner who looks after it. When we need to connect many of them into a single system, we hire experts and set aside large amounts of time and money for the job. The sheltered cyberworld of computers still hardly intersects with the real world of birds and trees, ships and bridges.

Where the two worlds do connect, it is often because people have carefully altered objects and methods of work to be computer-friendly. Stores stick bar codes on everything they sell or ship. Warehouse clerks attach radio-frequency identification (RFID) tags to pallets. Tagged goods must then funnel through a few scanners so that the computers can do their accounting.

The Stem Cell Challenge; June 2004; Scientific American Magazine; by Robert Lanza and Nadia Rosenthal, sidebar by Christine Soares; 8 Page(s)

Stem cells raise the prospect of regenerating failing body parts and curing diseases that have so far defied drug-based treatment. Patients are buoyed by reports of the cells' near-miraculous properties, but many of the most publicized scientific studies have subsequently been refuted, and other data have been distorted in debates over the propriety of deriving some of these cells from human embryos.

Provocative and conflicting claims have left the public (and most scientists) confused as to whether stem cell treatments are even medically feasible. If legal and funding restrictions in the U.S. and other countries were lifted immediately, could doctors start treating patients with stem cells the next day? Probably not. Many technical obstacles must be overcome and unanswered questions resolved before stem cells can safely fulfill their promise.

Nuclear Explosions in Orbit; June 2004; Scientific American Magazine; by Daniel G. Dupont; 8 Page(s)

On July 9, 1962, U.S. military researchers on a tiny Pacific atoll called Johnston Island fired a thermonuclear weapon into outer space. Code-named Starfish Prime, the launch onboard a Thor ballistic missile was the latest of a series of similar classified tests the U.S. Defense Department had begun four years before. But as the rocket rose on its smoky plume, few on the launch team realized that the forthcoming 1.4-megaton orbital burst was to yield surprising long-term results.

Hotel operators in Hawaii, some 1,300 kilometers away, were expecting a good show, though. Word had leaked of this latest "rainbow bomb" test shot, so a few enterprising resorts had organized rooftop parties from which guests could better view the distant fireworks. When the warhead detonated that evening at an altitude of 400 kilometers, it produced a brilliant white flash that momentarily lit up sea and sky like a noonday sun. Then, for about a second, the heavens turned light green.

Technicalities: Security at Your Fingertips; June 2004; Scientific American Magazine; by Mark Alpert; 3 Page(s)

Like many children of the 1960s, I have long entertained James Bond fantasies. While walking to work in midtown Manhattan, I often imagine myself as an agent for the British intelligence service, hunting down Dr. No or Goldfinger or Blofeld as the silhouettes of beautiful women dance languidly in the background. I drink vodka martinis (shaken, not stirred), and I would certainly drive an Aston Martin if I could afford one.

I recently got a chance to act out my spy dreams after I learned about a new class of fingerprint security systems that can work with your PC or laptop. These relatively inexpensive devices can protect your own top-secret electronic files by recording your fingerprint - any finger or thumb will do - on a small sensor attached by a USB line to your computer. Thereafter anyone seeking to open the files must place a finger on the sensor; if the print does not match the recorded data, access is denied. Fingerprint authentication can also provide an extra level of security when you're conducting transactions on the Internet. And the technology can stop hackers from breaking into corporate or government networks, because it's a lot harder to steal a finger than a password.

Reviews: Deploying Science to Desperate Ends; June 2004; Scientific American Magazine; by Claire Panosian Dunavan, staff editors; 2 Page(s)

Not long ago I got an e-mail from Nikki. My high school friend turned lawyer now communicates solely by laptop, propped in an electric wheelchair, twitching her lip to activate her keyboard. She is fed through a stomach tube, and a ventilator breathes for her 24/7. If a fly lands on her face, she is powerless to brush it away. Nikki has amyotrophic lateral sclerosis, also known as ALS or Lou Gehrig's disease. So do 30,000 other Americans, of whom 8,000 die every year.

Stephen Heywood, a six-foot-three carpenter from Boston, was 28 when his motor neurons began to fail. The earliest clue was subtle: he lost his first arm wrestling match in years to his older brother, Jamie. Then he couldn't turn a key in the front door of a house he was restoring. A year later he stumbled and pitched headfirst down a stairway. ALS is nothing if not relentless.

Anti Gravity: Take This Job and Do It; June 2004; Scientific American Magazine; by Steve Mirsky; 1 Page(s)

People often underestimate (or misunderestimate in special, high-level circumstances) the difficulties inherent in other people's jobs. Wake Forest University football coach Chuck Mills once summed up the phenomenon with this description of the average college football fan: "He's the person who sits 40 rows up in the stands and wonders why a 17-year-old kid can't hit another 17-year-old kid with a ball from 40 yards away. Then he goes out to the parking lot and can't find his car."

A new study, however, notes that there may be an actual neurological basis for our assumptions that other people have easier jobs than our own, or what I have found myself thinking of as "presumptive piker syndrome."

Ask the Experts; June 2004; Scientific American Magazine; by Staff Editor; 1 Page(s)

Perhaps it is unwelcome news, but neuroscience has found no vast, unused cerebral reservoir for us to tap. In addition, a study of self-improvement products by a National Research Council panel found that no "brain booster" is a reliable substitute for practice and hard work when it comes to getting ahead in life.

Why would a neuroscientist immediately doubt that 90 percent of the average brain lies perpetually fallow? First of all, it is obvious that the brain, like all other organs, has been shaped by natural selection. Brain tissue is metabolically expensive to grow and to run, and it strains credulity to think that evolution would have permitted the squandering of resources on a scale necessary to build and maintain such a massively underutilized organ.