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How to best curb greenhouse gas emissions is a hotly debated topic. But new research suggests that putting the brakes on greenhouse gas levels is not enough to slow down climate change because the ocean responds so slowly to perturbations. The study results, published today in the journal Science, indicate that even if greenhouse gas levels had stabilized five years ago, global temperatures would still increase by about half a degree by the end of the century and sea level would rise some 11 centimeters....

In the seventh century, during the Arab siege of Constantinople, the Byzantines introduced “Greek fire.” Consisting of a thick, flaming substance launched from cannons, it proved devastating during naval battles because the fire could not be extinguished and was said to burn Arab ships even below the water line. In today’s Pentagon parlance, that weapon would be known as a “disruptive threat”–something that comes out of left field to tilt the balance of power....

Even if Taliban forces and opium warlords do not try to interfere with mining by Afghan or international companies, other factors could complicate commercialization. Challenges faced at the country’s largest development project, the planned copper mine at Aynak, 20 kilometers south of Kabul, are emblematic. For one thing, the huge site that China Metallurgical Group leased for mining encompasses a national treasure: ruins of ancient Buddhist monasteries that many Afghans hope will be protected....

A failed Russian Mars probe came crashing back to Earth Sunday (Jan. 15) in a death plunge over the Pacific Ocean, according to Russian news reports. After languishing in Earth orbit for more than two months, the 14.5-ton Phobos-Grunt spacecraft fell at around 12:45 p.m. EST (1745 GMT) Sunday, apparently slamming into the atmosphere over an empty stretch of the Pacific, Russian officials told the Ria Novosti news agency. “Phobos-Grunt fragments have crashed down in the Pacific Ocean,” Alexei Zolotukhin, an official with Russia’s Defense Ministry, was quoted by Ria Novosti as saying....

Beauty is not just in the eye of the beholder—it is also in the eyes of the beholder’s friends. A study published in April in Psychological Science found that men judge a woman as more attractive when they believe their peers find that woman attractive—supporting a budding theory that groupthink is not as simple as once thought. Researchers at Harvard University asked 14 college-age men to rate the attractiveness of 180 female faces on a scale of 1 to 10....

Scientists have discovered exactly how the human brain gets its crinkly, wrinkly appearance in utero. It turns out that the huge explosion in the number of brain cells in the brain’s outer layer, called the cortex, forces that layer to swell and then collapse in on itself to form those characteristic creases. This cortical origami—which has also evolved in a handful of other brainy species, such as dolphins and some primates—may be nature’s way of solving the tight packing problem....

Helen Fisher, a biological anthropologist at Rutgers University and author of Anatomy of Love: The Natural History of Monogamy, Adultery and Divorce, responds: Several years ago I embarked on a project to see if the seven-year itch really exists. I began by studying worldwide data on marriage and divorce and noticed that although the median duration of marriage was seven years, of the couples who divorced, most did so around their fourth year together (the “mode”)....

Every year, the Nobel Foundation in Stockholm, Sweden, announces up to three winners each in the scientific disciplines of chemistry, physics, and physiology or medicine. As of this morning, since 1901, 780 individuals have joined the hallowed ranks of Nobel laureates in these and other categories. And every year, there are murmurings—some louder than others—about the Nobel-worthy scientists who were overlooked. In 1974, when Jocelyn Bell Burnell was left out of the physics prize, her fellow astronomer and Nobel reject, Fred Hoyle, told reporters it was a “scientific scandal of major proportions....

In a disappointing setback for the global effort to eradicate polio, two children have been paralyzed by the virus in Nigeria, which had gone two years without reporting a case. Prior to Thursday’s announcement by the World Health Organization, it had been thought that polioviruses were only circulating in two countries in the world, Afghanistan and Pakistan. The development is one the community of people fighting polio had been dreading. “I think of all of those things that have kept people in polio eradication up at night, this is the one that we have been most fearful of,” said Dr....

On a sweltering summer day in 2010, a construction worker in the southeastern Chinese city of Ganzhou was digging the foundation for a building when his backhoe smashed into something hard. Climbing down to see what it was, he probably expected the worst—impenetrable bedrock, an old water main or some other nuisance that would inevitably delay completion of the sprawling industrial park his crew was racing to finish. But when the dirt and smoke cleared, a very different culprit came into focus: bones—lots of them, some enormous....

We smile because we are happy, and we frown because we are sad. But does the causal arrow point in the other direction, too? A spate of recent studies of botox recipients and others suggests that our emotions are reinforced—perhaps even driven—by their corresponding facial expressions. Charles Darwin first posed the idea that emotional responses influence our feelings in 1872. “The free expression by outward signs of an emotion intensifies it,” he wrote....

One of the most widely prescribed drugs in the United States may have an extra benefit: protecting people from air pollution. Statins, prescribed to lower cholesterol and reduce risks of heart attacks and strokes, seem to diminish inflammation that occurs after people breathe airborne particles. “Health impacts from spikes in particulates in the air are substantial. Statins seem to protect not only lungs from these impacts but the heart, too,” said Dr....

Perhaps the best way to fight the decades-long decline of fish populations, primarily from overfishing, is to give the fishing industry clearer incentives to preserve them. That conclusion leapt from a recent analysis of the effect of “catch share” incentives by resource economist Christopher Costello and others at the University of California, Santa Barbara. The researchers analyzed more than 11,000 fisheries over 50 years and found that those being managed using catch shares were about half as likely to collapse as those without catch shares....

Over the past few years researchers have taken advantage of unprecedented advances in biology, electronics and human genetics to develop an impressive new tool kit for protecting and improving human health. Sophisticated medical technology and complex data analysis are now on the verge of breaking free of their traditional confines in the hospital and computer lab and making their way into our daily lives. Physicians of the future could use these tools to monitor patients and predict how they will respond to particular treatment plans based on their own unique physiology, rather than on the average response rates of large groups of people in clinical trials....

It’s normal to have a certain amount of fat in your liver, because processing dietary and blood fats is a big part of what the liver does. But in certain situations, fat can start to build up in the liver. If that goes on unchecked, it can cause inflammation, liver damage, and even liver cancer. In its early stages, a fatty liver doesn’t really cause any symptoms. It’s most likely to be detected through a physical exam, during which your doctor might be able to feel that your liver is enlarged....

Scientifically speaking, “metabolism” describes all the chemical reactions involved in being a living organism. Or, as Get-Fit Guy guest Angelo Poli of MetPro says, “The source of all frustration and agrivation in life.” Does your metabolism prevent you from maintaining a healthy weight? If so, can metabolic profiling help? Like your thumbprint, your metabolism is unique to you based on your genetics, lifestyle, dietary history, and general health and fitness levels....

At a psychology laboratory in Leipzig, Germany, two toddlers eye gummy bears that lie on a board beyond their reach. To get the treats, both tots must pull in tandem on either end of a rope. If only one child pulls, the rope detaches, and they wind up with nothing. A few miles away, in a plexiglass enclosure at Pongoland, the ape facility at the Leipzig Zoo, researchers repeat the identical experiment, but this time with two chimpanzees....

Why is Google worth so much more than Yahoo? They both make their money from showing ads on the web, and they’re both top destinations. Both use auctions to sell ads and machine learning to predict how likely a user is to click on an ad (the higher the probability, the more valuable the ad). But Google’s learning algorithms are much better than Yahoo’s. This is not the only reason for the difference in their market caps, of course, but it’s a big one....

Suzan Obagi, assistant professor in dermatology at the University of Pittsburgh and director of the Cosmetic Surgery and Skin Health Center, explains. Normal healthy skin has a nice epidermis with a smooth cornified, or outer, layer that acts as a good barrier to water and environmental injury. Skin color and tone is even and unblemished. Components such as collagen (which provides skin firmness), elastin (which supplies skin elasticity and rebound) and glycosaminoglycans or GAGs (which keep the skin hydrated) are all abundant....

Editor’s note (11/16/15): Following the terrorist attacks in Paris on November 13, Scientific American is republishing the following article, which originally ran after the attack on Charlie Hebdo, a Parisian newspaper, in January 2015. In the wake of terrorist attacks last week on the French satirical magazine Charlie Hebdo and a Paris supermarket, the world has struggled to understand the combination of religion, European culture and influence from terrorist organizations that drove the gunmen....