If the mail I get from readers is any indication, the issue of climate change is a dastardly conspiracy to “redistribute global wealth,” as one memorably explained to me. Now greenhouse deniers can imagine another conspiracy: it is all a plot to get rid of fat people.

The link between obesity and climate change has come up before, although subtly. An AP story last year noted that people could combat both of these problems by walking or bicycling rather than driving (so they burn calories, not gasoline). And writing in the Huffington Post, filmmaker Bryan Young (“Killer at Large”) cited a scientist who told him that “for every pound the average American is overweight, we use an additional 938 million gallons of gasoline per year. That's enough to fill 2 million cars with gasoline every year.” It’s straightforward physics: it takes more energy to move a lot of weight than it does to move a little weight (which is also why, everything else being equal, big cars get worse gas mileage than subcompacts).

Now a paper in The Lancet today puts a scientific stamp on this. The logic goes like this: Fat people consume more food than thin people, it takes energy to grow and transport food, ergo fat people are responsible for more global warming than thin people. Or, more precisely, for 18 percent more food energy than normal people, calculate Phil Edwards and Ian Roberts of the London School of Hygiene and Tropical Medicine.

The standard definition of “overweight” is having a body mass index of 25 or greater (you can calculate yours here). A population with BMIs of 24.5 consumes, on average, 1550 calories of food per person per day just for basic metabolism and another 950 calories for daily activities. That’s 2500 calories each. A population with BMIs of 29 needs 1680 calories per person for basic metabolism, plus 1280 calories for daily activities, or 2960. That’s 18 percent more food energy.

In addition, it takes more fuel to move an obese person than a slender one, the authors note, something that “will increase further if, as is likely, the overweight people in response to their increased body mass choose to walk less and drive more.” The authors therefore advocate policies that promote walking and bicycling to reduce obesity and, hence, global warming.

But I can’t help reading in their paper the latest pretense for feeling greener-than-thou: it won’t be enough to drive a Prius, air-dry your laundry, become a vegan and ditch your air conditioning to feel smug about your tiny carbon footprint. Not you’ll have to be waif-thin, too.

Here’s a moral dilemma that seems tragically timely, given the chaos surrounding attempts to deliver aid to Burma’s cyclone victims. There are 60 orphans at the Canaan Children’s Home in Buziika, Uganda, and their meal allotment has to be cut. What do you want to do: take six meals away from each of two kids, or 10 meals away from one? You have eight seconds to decide.

In this and similar moral dilemmas, efficiency (the total number of meals lost) is pitted again against equity (how evenly the burden of lost meals is shared among the children). You have to take away a total of 12 meals if two children share the loss, but only 10 (which would seem better) if a single orphan bears the entire burden. You have to decide whether to sacrifice efficiency (losing fewer meals) to equity (spreading the loss over more children).

Here’s another way to think about it. You are driving a truck to the Burmese cyclone victims. It holds 1,000 pounds of rice. The time it will take to deliver the rice to everyone in the Irrawaddy Delta village you are headed for means that 200 pounds will spoil. If you deliver the rice to people you meet en route, you will be distributing it to only half the population of the village, but only 50 pounds will spoil. Do you deliver the rice to only half the number of victims, maximizing the total amount of food provided (efficiency), or do you sacrifice 150 pounds to distribute it to more people (equity), giving rice to more people but also causing more rice to go to waste?

In a study reported online today in the journal Science, researchers posed the orphan dilemma to people while scanning their brains with functional magnetic resonance imaging (fMRI). Unlike most studies of the brain basis of ethical decision making ("neuroethics"), this one was grounded in reality: the volunteers’ choices would determine how many meals the research team actually donated to the Ugandan orphans. The volunteers knew this, which made the dilemma painful in the extreme. “Quite a few came out saying: ‘This is the worst experiment I’ve ever been in. I never want to do anything like this again!’,” said study co-author Ming Hsu of the University of Illinois’s Beckman Institute for Advanced Science and Technology.

So, which is more critical to our sense of justice, equity or efficiency? And how does the brain decide?

In the experiment, the volunteers (26 men and women, ages 28 to 55) first read short bios of the orphans. Then they watched a video on a computer screen, showing a ball rolling toward a lever. By moving the lever, they could steer the ball toward either of two depictions of the moral choices: photographs of the actual orphans who would be affected by that choice, with numbers for the number of meals that would be lost to those children if that option were chosen.

By an overwhelming margin, people chose to preserve equity at the expense of efficiency—lose a few more meals, but spread the burden among as many children as possible, rather than making one hungry child—whose imploring little face stared back at them from the screen--shoulder the entire loss.

According to the fMRI, different brain regions became active at different points in the decision-making. The insula, which is involved in processing emotions and the awareness of bodily states as well as (in some studies) evaluating fairness, was active when the volunteers wrestled with questions of equity. The putamen, which is activated during learning that brings rewards, lit up when people thought about efficiency.

Since equity won, it suggests that decisions about fairness are rooted in emotion more than in cold-eyed cost-benefit analysis. “That the brain has such a robust response to unfairness suggests that sensing unfairness is a basic evolved capacity,” Steven Quartz of Caltech and co-author of the study said in a statement. “The emotional response to unfairness pushes people from extreme inequity and drives them to be fair,” suggesting that “our basic impulse to be fair isn’t a complicated thing that we learn,” but an instinctive one.

And whoever said scientists have no heart? After the experiment, and based on the volunteers’ decisions, the team donated $2,279 to the orphanage.

The 1999 comedy Dogma opens with a disclaimer, exhorting the audience to remember that “even God has a sense of humor. Just look at the Platypus. Thank you and enjoy the show. P.S. We sincerely apologize to all Platypus enthusiasts out there who are offended by that thoughtless comment about Platypi. We at View Askew respect the noble Platypus, and it is not our intention to slight these stupid creatures in any way. Thank you again and enjoy the show.”

God expressed his sense of humor, of course, in assembling a creature that is a little bit mammal (the platypus, a native of Australia, produces milk and is furry), a little bit reptile (it lays eggs and has venom, released from spurs in the hind legs) and a little bit bird (eggs again, plus it has a bill like a duck as well as webbed feet). Its cognitive capacity and/or nobility we’ll leave to the guys at Dogma, but one particular platypus—Glennie, from New South Wales, Australia—has made scientists smarter: an international team of researchers from the U.S., Australia, England, Germany, Israel, Japan, New Zealand and Spain collected her DNA and from it sequenced the platypus genome, they’re announcing today in papers in Nature and Genome Research.

The platypus genome consists of roughly 2.2 billion pairs of chemical “letters,” those As, Ts, Cs and Gs that spell out a species’ genetic code. (Humans have about 3 billion.) Within those letters are some 18,500 genes, compared to maybe 24,000 in humans.

Not surprisingly, the platypus genome is an amalgam of mammal, reptile and bird DNA, too.

Like reptiles, the platypus (Ornithorhynchus anatinus) has genes for egg laying. Its venom comes from genes that are duplicates of genes that evolved in ancestral reptiles, which is also the source of venom in today’s reptiles. Like mammals, it has genes for lactation (though, lacking nipples, it nurses its young through the abdominal skin). Like birds, it has a weird way of determining sex: of its 52 chromosomes, 10 are sex chromosomes (in humans, the X and Y, of 23 chromosomes, are sex chromosomes), and the platypus X resembles the sex chromosome of birds, called Z. A female platypus has five pairs of X chromosomes, while males have five Xs and five Ys. The platypus genome contains both reptilian and mammalian genes involved in the fertilization of eggs. Unlike most mammals, which have a pretty good sense of smell, the platypus doesn’t—and its genome has about half as many odor receptors as the mouse and other mammals.

Just one request, please. In the PR avalanche preceding this announcement, one talked about the medical benefits that would surely come from this feat. ("What does this discovery mean for the public? The very real potential for advances in human disease prevention and a better understanding of mammalian evolution.") Aren't we beyond that yet? There have been virtually no medical benefits from sequencing the human genome (yet), for goodness sake; can't we, just occasionally, celebrate a feat of pure science without raising hopes that it will, you know, cure cancer or something? Sometimes a platypus genome is just a platypus genome.

The thrill is gone.

Maybe voters are simply tired of the seemingly endless campaign for the Democratic nomination. Or maybe their excitement about the new (Barack Obama), the suddenly emoting (Hillary Clinton, in New Hampshire) or the coming-back-from the-politically-dead (John McCain) can’t last forever. But whatever the reason, voters are feeling much less excitement and fewer positive emotions about all three of the remaining presidential candidates than they once did, finds a poll that, uniquely, measures voters’ emotional reactions.

If the trend continues, that’s bad news for the candidates, because research keeps showing that voters base their decisions more on their hearts than their heads and are easily swayed by anxiety, fear and other negative emotions. Latest evidence: anyone who feels—the key word—that Obama doesn’t understand “people like me” because he said that voters embittered about their economic plight “cling to guns or religion or antipathy to people who aren’t like them.” If that loses him any votes, it will not be because of a rational analysis of his record and positions, but because of how it made people feel about him.

Anyway, a company called AdSam measures what it calls “Emotional Temperature,” which gauges people’s emotional engagement with a product, website or advertisement. Since, as we all know from Joe McGinniss’s 1969 book, “The Selling of the President, 1968,” candidates are marketed and sold just like detergent, the same technique should work with politicians.

In its latest study, AdSam measured how strongly voters feel about each candidate, and how engaging they find them. Since last September, Clinton’s “emotional temperature has been on a continual steep decline with voters,” says AdSam president Jon Morris, a professor at the University of Florida, dropping from 93 to 70 (where 173 is how emotionally positive voters say they would like to feel about a candidate). “Her emotional cool-off is a sign that she is not relevant and not making connections with voters. This is a significant barrier for her and will be very difficult for her to turn around.”

Clinton trails both McCain and Obama, whose emotional temperatures are very similar (85 and 88, respectively, this month) and have not fallen off a cliff the way Clinton’s has. Obama dropped 8 points from September to January (97 to 89), and has stayed at about that “temperature” since. McCain moved up 9 points from September to January (79 to 88), but is down 3 points since.

Obama generates the most positive emotional response among Democrats (beating Clinton 120 to 97) and beats McCain among Independents (97 to 81), with Clinton at 74 among Independents. McCain has finally excited and united Republicans, however, zooming from 101 last September to 145 now.

Clinton is leaving more voters cold, says Morris. Compared to last September or even January, fewer voters feel “interested/excited” by her, while more feel “reluctant,” “uninterested/unexcited” and even “disgusted.” The biggest reason for the turnaround, Morris finds, is that more voters perceive Clinton as dishonest.

Obama is making more Democrats “interested/excited” now than he did in January, but more are also feeling “ambivalent” about him. In follow-up interviews, voters use words such as “truthful,” “honest,” “trust” and “inspirational,” but more and more cite his scant experience on the national stage. The Illinois senator has further to go with Independents: 21 percent feel strong positive emotions about him, compared to 32 percent last September. Equally worrisome, 28 percent now feel “ambivalent,” the most of any emotion among Independents asked about Obama.

More Democrats (20 percent) were disgusted by Clinton’s dishonesty about coming under fire during a trip to Bosnia than by Obama’s links to his controversial pastor (10 percent). We'll see how this translates into votes in Pennsylvania next Tuesday.

I’ll leave it to political reporters to explain why, of all the cringe-inducing business dealings that Mark Penn kept his hand in as chief executive of the PR titan Burson-Marsteller even as worked for Hillary Clinton’s presidential campaign, it was his work on behalf of Colombia to secure passage of a bilateral trade agreement with the U.S. that led to his downfall. Yesterday he quit as Clinton’s chief political strategist, though he’ll stay on as a pollster.

I have no idea whether a Colombian trade agreement would be good for the U.S. But I do know that Burson-Marsteller’s work on behalf of the high-mercury fish industry is an excellent way to get even more neurotoxins into babies’ developing brains. Burson-Marsteller has worked tirelessly to persuade people—especially pregnant women—that the mercury that tuna (especially albacore) is laced with is nothing to worry their pretty little heads about.

Last year, the New York Sun reported that it had obtained Penn’s internal blog entries, including one from Dec. 20, 2006, in which he brags about landing the U.S. Tuna Foundation’s PR business. His company pitched “ideas for how to act like a political campaign by neutralizing the negatives and bringing out the heart healthy benefits of tuna,” Penn wrote, according to The Sun.

The issue of mercury in tuna makes the industry apoplectic (as you can see from its response to an earlier blog item). But Clinton had, as a senator, stood with those trying to protect children, not the industry, when she signed a 2004 letter criticizing the Environmental Protection Agency for soft-pedaling its own advisory about mercury in fish (especially albacore tuna, since canned tuna is the fish Americans eat more of than anything other fish besides pollock), which “specifically informs women that they and their young children should limit consumption of tuna.”

My favorite story about the Dalai Lama doesn’t concern his activities on behalf of Tibet, which is one unrelieved tragedy, but is about his interest in neuroscience. A few years ago the Dalai Lama was visiting an American medical school and watched a brain operation. Afterwards, he chatted with the surgeon, telling him how his scientist friends had patiently explained to him that all of our thoughts, feelings, memories, dreams and other mental activities are the products of electrical and chemical activity in the brain. But he had always wondered something, the Dalai Lama told the surgeon. If electricity and chemistry can produce thoughts and all the rest, can thoughts act back on the physical stuff of the brain to change its chemical, electrical and other physical properties?

The surgeon dismissed the question with a polite but indulgent no. (The Dalai Lama's English translator, Thupten Jinpa, told me this story in 2005.) The brain produces and shapes mental activity, the brain surgeon said; mental activity does not alter the brain.

That wasn’t a stupid answer 10 years ago, before scientists had fully grasped the potential of the adult brain to change in structure and function—an ability called neuroplasticity. But now researchers have documented a long list of examples of how the brain, once thought to be basically unchangeable after the ripe old age of 3, can indeed change.

The first things that were found to change the brain were sensory inputs. If you spend a lot of years playing violin, say, then the regions of the motor and somatosensory cortexes that correspond to the fingering digits (the fingers on the left hand, if you're right-handed) expand.

But now neuroscientists have documented how “mere” thoughts can also sculpt the brain. Just thinking about playing a piano piece, over and over, can expand the region of motor cortex that controls those fingers; just thinking about depressive thoughts in new ways can dial down activity in one part of the brain that underlies depression and increase it in another, leading to clinical improvement.

The scientist who has worked most closely with the Dalai Lama is Richard Davidson of the University of Wisconsin, Madison. Davidson first met the Dalai Lama in 1992, and since about 2000 has been investigating a question dear to the heart of the leader of Tibetan Buddhism: can mental training such as meditations change the brain in an enduring way? That “enduring” is key: of course the brain “changes”—in the sense that some areas become more active—when you meditate, just as it changes when you think of pink elephants, watch Obama or try to remember your first kiss. Everything we think has a corresponding brain activity. But once the thought stops, so does the activity. Usually. What Davidson wanted to know was whether meditation left a long-lasting imprint on the brain, some change of function or structure.

Since 2004, Davidson and his colleagues have reported that meditation can alter the brain’s attention capabilities and that it can increase production of brainwaves called gamma, which are associated with consciousness. Now they have found another long-lasting brain change produced by Buddhist meditation: practicing compassion meditation (more on this below) alters regions of the brain that make us empathetic, Davidson and his colleagues are reporting this evening in PLoS ONE.

In compassion meditation, as the French-born Buddhist monk Matthieu Ricard explained it to me when we were both visiting the Dalai Lama in Dharamsala for a meeting of neuroscientists and Buddhist scholars, you focus on the wish that all sentient beings be free of suffering. You generate an intense feeling of love for all beings, not fixating on individuals but encompassing all of humanity. It takes practice, since the natural tendency is to focus on one or a few specific suffering people.

Davidson conducted his new study as he has his others on meditation, enlisting expert meditators (the Dalai Lama has asked Buddhist scholars to volunteer their brains to Davidson’s research). Antoine Lutz has the meditators (monks who have 10,000 hours or more of meditation under their belts—er, saffron robes) lie in a functional magnetic resonance imaging (fMRI) tube. The fMRI detects which regions of the brain are active during meditation and which are quiet. It also detects which are active during periods between meditations. The scientists compare these readings to those on non-meditators, who undergo a quickie course in compassion meditation. In this case, Davidson and Lutz enlisted 16 monks plus 16 age-matched controls, members of the UW-Madison community.

Each of the 32 subjects lay in the fMRI and turned compassion meditation on and off, on Lutz’s command. Throughout, Lutz piped in happy sounds (a baby laughing and cooing), distressed ones (a woman who sounded as if she were in pain) and neutral ones (restaurant noise). Two regions lit up with activity:

Brain-imaging studies have proliferated so mindlessly (no pun intended) that neuroscientists should have to wear a badge pleading, “stop me before I scan again.” I mean, does it really add to the sum total of human knowledge to learn that the brain’s emotion regions become active when people listen to candidates for president? Or that the reward circuitry in the brains of drug addicts become active when they see drug paraphernalia?

Sometimes, though, a brain-imaging study does tell us something we didn’t know. I’d wager that most people do not know how much of their brain power cuts out when they listen to a conversation that demands even a modicum of cognitive power. If polite requests have not made your significant other, kids or other passengers shut up when you're behind the wheel, maybe this will.

Researchers at Carnegie Mellon University had 29 volunteers use a trackball or mouse to drive along a (virtual) winding road at 43 miles per hour in a simulator while having their brain scanned. As they report in a study scheduled for publication in the journal Brain Research, listening and concentrating on spoken questions reduced by 37 percent the amount of activity in a brain circuit that you tap for driving. Result: drivers weaved out of their lane in the simulator, just like drunks.

In one condition the volunteers drove along undisturbed, while in the other they heard sentences and had to decide if they were true or false by pressing a button with their left hand. (Among the statements: "botany is a biological science and it deals with the life, structure, and growth of plants,” and “a phobia refers to a person’s extreme attraction to some object, situation, or person.”)

When the drivers were thinking about the sentences, activity fell by 37 percent in their brain’s parietal lobe, which integrates sights, sounds and other sensory information to form a sense of where you are in space and allows you to navigate. Activity also fell in the occipital lobe, which processes visual information. (The drivers got 92 percent of the true/false questions right, suggesting they were listening hard and focusing on them.) The scientists conclude, “the addition of a sentence listening task decreases the brain activation associated with performing a driving task, despite the fact that the two tasks draw on largely non-overlapping cortical areas.”

The consequences of that drop in brain activity showed in the simulator. Driving with one lobe tied behind their backs, as it were, the distracted volunteers hit a simulated guardrail and failed to keep to the middle of the lane significantly more than when they were driving without someone yakking at them.

“Engaging in a demanding conversation could jeopardize judgment and reaction time if an atypical or unusual driving situation arose,” says CMU neuroscientist Marcel Just, director of the Center for Cognitive Brain Imaging and leader of the study. He has a hunch that cell phones may be especially distracting—more so than listening to the radio or to a conversation with a passenger—because you can more easily tune out the radio when you have to concentrate on the road, and a passenger will usually shut up when she sees that you have to focus on the traffic. But cell phones have a certain rude insistence.

Our cell-phone laws are bedeviled by one little problem: epidemiological studies show that the rate of accidents among people who use hands-free phones is equal to that of people using hand-held phones. That makes laws requiring the former hard to justify, if well-intentioned. I’ll let Just and his colleagues say it: Findings such as those in this study "suggest that the deterioration in driving performance resulting from cellular phone usage results from competition for mental resources at a central cognitive level rather than at a motor output level, and that legislative measures which simply restrict drivers to the use of hand-free phones fail in their intent to limit an important distraction to driving."

Warning to anyone planning a crime: don’t drink the water.

Scientists are reporting this evening that an analysis of hydrogen and oxygen isotopes in human hair reveals where a person drank water, which will allow investigators to figure out if a suspect was in the vicinity of a crime—and also to track past movements of unidentified murder victims.

The new technique analyzes isotopes of hydrogen and oxygen, forms of the elements that have an extra neutron in its atomic nucleus. The ratio of oxygen-18 to oxygen-16 in air is the same everywhere, and ratios of both hydrogen and oxygen ratios in food are also basically the same across the country because the American food supply is so uniform. But water is still like a microbrew, containing different constituents depending on where it comes from.

As a result, geochemist Thure Cerling and ecologist Jim Ehleringer of the University of Utah report in the journal Proceedings of the National Academy of Sciences, a single hair bears clues to where someone has been over the last few weeks or even years, depending on the length of the hair. “You are what you eat and drink—and that is recorded in your hair,” said Cerling in a statement from the university.

Salt Lake County Sheriff's Detective Todd Park is using the hair-isotope method to try to identify a murdered woman whose remains were found by hunters near Interstate-80 along the south end of the Great Salt Lake on October 8, 2000. Detectives recovered 26 bones, some hair, a T-shirt and a necklace. Despite creating a facial reconstruction and publicizing it nationally, the police have been unable to ID the woman, who stood about 5 feet tall and was 17 to 20 years old when she was killed. But when Park arranged with Ehleringer for an isotope analysis of the victim’s hair, it showed that for the last two years of her life she lived in the Northwest, mostly in the Idaho-Montana-Wyoming area, and maybe into Oregon and Washington. Park hopes that examining missing persons records from those areas will lead to an ID.

Ehleringer and Cerling are co-founders of IsoForensics, Inc., which sells isotopic analysis of forensic substances. A method Ehleringer developed to trace the origins of cocaine or heroin is now used by the a method now used by the U.S. Drug Enforcement Administration: variations in the amount of carbon, nitrogen, oxygen and hydrogen isotopes in soil and water show up in coca and poppy plants.

For the hair analysis, says Ehleringer, “You can tell the difference between Utah and Texas,” but probably not Chicago and Kansas City. In general, the amount of the heavy isotopes oxygen-18 and hydrogen-2 levels in drinking water decreases as you move inland from the West Coast: as rainstorms move off the Pacific Ocean, rain drops containing oxygen-18 and hydrogen-2 tends to fall first because it is heavier. But cloud temperatures and season also affect which isotopes rain drops contain, with the result that heavy isotopes are also relatively more common in water inland from the Gulf and southern Atlantic coasts. The lowest concentrations of hydrogen-2 and oxygen-18 are found in water in northern and western Montana, north-central Idaho and northwest Wyoming (because the heavy isotopes drop out of clouds before they reach these inland areas), while the highest amounts of hydrogen-2 and oxygen-18 in drinking water and hair are in southern Oklahoma, north-central Texas, Florida, south Georgia and southern South Carolina (in warm regions with more evaporation, lighter-isotope water evaporates from surface sources first, leaving heavier-isotope water behind to find its way into drinking water.

Just for the record, reporters take no pleasure in questioning the power of drugs to treat depression. To the contrary: journalism is notorious for attracting curmudgeons, grumps and depressives—some of my best friends are one or more of the above—so we wish with all our hearts that antidepressants would work.

And that scientists wouldn't keep finding evidence that they do not.

In January I reported on the file-drawer effect in studies of antidepressants. The file-drawer effect refers to the fact that scientifically-sound studies on the efficacy of antidepressants are not published, as The New England Journal of Medicine article described. Most of those studies were negative—that is, the drugs did not help patients much more than a sugar pill (placebo) did, if they helped at all. That skews the perception of doctors, scientists and you and me about these drugs; basing our assessment of antidepressants on published studies alone is like evaluating the prowess of a baseball team when only its wins and not its losses are reported.

Now a team of scientists has examined many of those unpublished studies, obtained through a Freedom of Information Act request for the U.S. Food and Drug Administration. As many people feared, once you include the deep-sixed studies, antidepressants look hardly more effective than a placebo at lifting patients’ black cloud of despair.

For their analysis, scientists led by Irving Kirsch of Britain’s University of Hull started with the data dump they got from the FDA on fluoxetine (Prozac), venlafaxine (Effexor), nefazodone (Serzone), and paroxetine (Seroxat /Paxil). They zeroed in on differences between the improvement reported by patients receiving the drug and those receiving a placebo. As is standard in such clinical trials, neither the patients nor the scientists running the study knew which patients were receiving real drugs and which were receiving placebos.

In short, there was virtually no difference in the response to drug vs. placebo of patients who suffered moderate levels of depression, and a small difference for patients with very severe depression, they report in the study published this evening in the journal PLoS Medicine. That small difference was, however, clinically insignificant—that is, the difference was so small that government health authorities do not recognize it as a meaningful improvement: on a standard scale of depression, patients should improve by 3 points, but the spread between placebo and drug was only 1.8. The difference between drug and placebo was clinically meaningful only for patients at the upper end of the very severely depressed category.

The reason for the tiny, or nonexistent, differences? Patients respond so well to placebo—to the mere thought that something might be helping them—that there was little room for an actual drug to do more. Across all groups, response to placebo accounted for more than 80 percent of any improvement. (In contrast, the placebo response to pain drugs is estimated at about 50 percent.) That suggests that even when patients are taking and benefiting from, say, Zoloft, the vast majority of the improvement is due to what their minds are telling them—that is, the belief that they would be helped. Only the most depressed patients showed little placebo response.

The scientists conclude that there is little reason to prescribe the new antidepressants to any but the most severely depressed patients except as a last resort. Kirsch summarized the findings this way: “Although patients get better when they take antidepressants, they also get better when they take a placebo, and the difference in improvement is not very great. This means that depressed people can improve without chemical treatments.”

But it seems that there is a larger message here. The placebo response—the belief that treatment will make you better—is enormously powerful. Surely it’s time to investigate further how it works and how it can be harnessed.

Bringing Sexy Back: Leah and Partner. Photo:Thomas Breuer - WCS/MPI-EVA.

Scientists from the Wildlife Conservation Society and the Max Planck Institute for Evolutionary Anthropology were minding their own business recently while studying western lowland gorillas in Nouabalé-Ndoki National Park in the Republic of Congo when they saw what no one has ever recorded: Leah and her sweetheart trying to make baby gorillas through face-to-face copulation. Curiously, Leah was also the first wild gorilla to be observed using tools, scientists reported in 2005. (She used a stick to determine the depth of a pool of water before wading into it.) A true pioneer, indeed.

Face-to-face (or, technically, ventro-ventral) copulation is extremely rare in the animal kingdom. Before lowland gorillas joined the club, only people and bonobos (a chimp cousin known for really, really enjoying recreational sex) had been known to look at their partner while mating. From time to time, a scientist in the field reported seeing mountain gorillas mate face-to-face, but the sightings were like those of Bigfoot: no photo, no count. Captive western gorillas have also been known to mate face-to-face, but scientists always wondered if that was an artifact of living in a zoo, not natural.

Thomas Breuer of the Max Planck says, “we can’t say how common this manner of mating is, but it has never been observed with western gorillas in the forest. It is fascinating to see similarities between gorilla and human sexual behavior.” Let that serve as inspiration for the 14th.

Say 'Om': With the Beatles in 1968. Photo: Getty Images

The other legacy the Maharishi, who died on Tuesday, gave the West is more controversial. In 1971 he founded Maharishi International University, in Iowa (now called Maharishi University of Management), which has become the center for studies of Transcendental Meditation (TM). Almost immediately—research papers on the benefits of TM appeared as early as 1974—scientists there began researching how TM affects everything from job satisfaction to blood pressure to anxiety.

There was just one problem. “Those early studies were extremely tendentious and just not of high caliber scientifically,” B. Alan Wallace, president of the Santa Barbara Institute of Consciousness Studies, told me last fall.

In the early days, many studies compared people who meditate to those who do not. That made some of their conclusions suspect: if meditators have lower levels of stress than non-meditators, as studies found, that might be because only already-mellow people choose to meditate and stick with it, not because of the practice itself.

Still, it would be churlish to deny the numerous studies reporting benefits from TM. One found that learning TM reduced hypertension in older African-American men. Others reported that meditation can moderate the harmful effects of strenuous physical exercise on the immune system, that it can produce a feeling of euphoria akin to “runner’s high”, and that it reduced anxiety more than other relaxation techniques. Maharishi University regularly updates the list of research results.

But scientists are not fully convinced. It has been difficult to rule out an alternative explanation for apparent benefits such as reductions in stress, blood pressure and heart rate—namely, the placebo effect. If you expect an intervention, be it a pill or learning TM, to help you, it often does. If you are testing the benefits of a pill, you can give half your study subjects a dummy pill but not tell them, which can help control for the placebo effect. It’s pretty hard to hide from test subjects the fact that they are learning to meditate and then doing so for several hours a week. Perhaps it is the belief that TM will do wonderful things that produces benefits, not the actual meditation. That question remains very much up in the air.

Despite these concerns, the Maharishi and his American acolytes deserve credit for introducing the study of meditation to biology. Hospitals from Stanford and UCLA to Duke and NYU have instituted meditation programs to help patients cope with chronic pain and other ailments. Scientists unaffiliated with the TM movement have been emboldened to study the effects of other forms of meditation on diseases as different as depression, obsessive-compulsive disorder and psoriasis, all with impressive results. Whatever you think of the White Album, give the Maharishi credit for helping to launch what has become a legitimate new field of neuroscience.

I consider myself an open-minded person. So just because a group attacks drunk-driving laws and anti-smoking regulations, just because it opposes replacing the junk food in school cafeterias and vending machines with healthy snacks, just because it opposed reducing the blood-alcohol level that constitutes the legal definition of drunk, and just because it calls concerns about obesity “hype,” do I dismiss its defense of mercury in tuna fish?

Of course not.

So when the Center for Consumer Freedom sent me (and probably scores of other reporters) a press release slamming yesterday’s New York Times story chronicling the high mercury levels the newspaper found in tuna sushi served in New York City restaurants and sold in upscale stores, I didn’t reflexively think, “oh, this is the group jump-started with a pile of money from a tobacco giant.” I didn’t think, “this is the group whose leader promised said tobacco company, Philip Morris, ‘to unite the restaurant and hospitality industries in a campaign to defend their consumers and marketing programs against attacks from anti-smoking, anti-drinking, anti-meat, etc. activists.’” I didn’t automatically recall the Washington Post editorial citing “documents showing that Coca-Cola, Wendy's, Tyson Foods, Cargill and Outback Steakhouse are among [founder Rick] Berman's largest donors.” I didn’t automatically recall that Berman had, as the Post reported, “accused Mothers Against Drunk Driving a. . . of ‘junk science, intimidation tactics, and even threats of violence to push their radical agenda.’” (I found those references only later.)

Think of one word that can form a compound word with “sauce,” “pine” and “crab.”

I’ll wait . . . .

Time’s up: did you come up with “apple,” to make “applesauce,” “pineapple” and “crabapple”? OK, let’s consider that a warmup. Try the same exercise—finding a word to make a compound word—with “bump,” “step” and “egg.”

Did “goose” pop into your head?

One more: for “back” “clip” and “wall.” . . . .It’s “paper,” for “paperback,” “paperclip” and “wallpaper.”

If you’re like many people, you tried to solve each problem methodically, first finding a word that would go with, say, “sauce” and then trying it out with “pine” and “crab.” But if you’re like most people in a more important way, if you solved these brain-teasers you did so not through this grind-through-the-possibilities approach, but through insight. That is, you thought a little and then, wham, the answer suddenly hit you.

Scientists have approximately no idea how this happens.

Yeah, you’ve probably heard that before, since Newsweek  and other publications have chronicled the Bush Administration’s efforts to squelch scientists who conclude that climate change is real, caused by human activities and not a good thing, to put it mildly. Still, there’s something about having it all tied up in a neat congressional report, as Rep. Henry Waxman is releasing this morning, that really hits you in the face.

Unlike mere journalists, to whom sources can lie with impunity, congressional investigators have the power to put people under oath, holding over them the prospect of a perjury indictment if they lie. Funny how that leads to all sorts of revelations. Media requests to interview climate scientists were routinely punted to the White House environment office, says one career official. Asked by Waxman’s staffers, “Did the White House and the Department of Commerce not want scientists who believed that climate change was increasing hurricane activity talking with the press?” he said, “There was a consistent approach that might have indicated that.”

The White House also knew better than scientists what the research showed, apparently, for when Thomas Karl, director of National Climatic Data Center, appeared before Waxman’s House Oversight Committee last year, his testimony was edited by White House officials and the Commerce Department. According to Waxman’s investigators, “He was not allowed to say in his written testimony that ‘modern climate change is dominated by human influences,’ that ‘we are venturing into the unknown territory with changes in climate,’ or that ‘it is very likely (>95 percent probability) that humans are largely responsible for many of the observed changes in climate.’ His assertion that global warming ‘is playing’ a role in increased hurricane intensity became ‘may play’.” There are plenty more where that came from.

And people still wonder why so many Americans do not understand climate change?

Scientists are sticklers for not really believing what until someone explains how. That is, they’ll see that something happens, but until research reveals how it happens the phenomenon remains a bit dodgy.

So it is with the power of exercise to spur the production of new neurons in the brain, improve learning and lift depression. Fred Gage and colleagues at the Salk Institute showed in 2005 that it does happen—even elderly rats have a spurt of this “neurogenesis” after a few sessions in the exercise wheel. And researchers led by Arthur Kramer at the University of Illinois showed in 2006 that the effect occurs in people, too, so that even a hour a day of mall-walking increases the amount of gray matter in the brains of the elderly. It also makes you feel better.

Maybe now more scientists, not to mention the rest of us, will take the findings to heart. Researchers led by Ronald Duman of Yale have discovered that exercise causes the brains of mice to produce a molecule that acts as a natural antidepressant, they write this afternoon in the online edition of Nature Medicine. The molecule is a growth factor called VGF, which is active in the brain.

That nearly ties up three loose ends: exercise, neurogenesis and anti-depressants. That's because, over the last few years, scientists have been challenging the idea that antidepressants such as Prozac work by increasing the brain’s production of serotonin. Instead, the drugs' real mechanism is to spur neurogenesis. With the new work, there’s at least the possibility that the drugs do so through VGF. The current study shows that “VGF is required for the antidepressant effects of exercise,” the scientists say. Interesting, the most effective treatment for depression, electroconvulsive shock, also increases the brain’s supply of many of the molecules that exercise does, including VGF.

The next step is to confirm that exercise also raises levels of VGF in people's brains, not just mice's. But as anyone who has experienced a glow or even a euphoria from working out can attest, exercise has a profound positive effect on mood--and now we know how.