N Nitrogen

In western North America the mountain pine beetle --the most destructive of the many species collectively known as bark beetles--is on a pine tree–killing spree. Since the 1990s swarms of the tiny killer, spurred in part by a streak of relatively mild winters that don't kill the insect, along with dry summers that leave trees more vulnerable to attack, have destroyed huge swaths of pine forests--around 16 million hectares (an area larger than Florida) in British Columbia alone. The beetles are now threatening to move eastward, and research ecologists are working to rapidly build a better understanding of exactly how the insect invasion kills trees, searching for insights that might allow forestry workers better cope with the epidemic. [More]

Whether incited by handicap, illness or drug use, the romantic movement was full of ghastly imaginings--such as those painted by Francisco de Goya--and fantastic scenes--as described in Samuel Taylor Coleridge's "Kubla Khan." At least one great music mind of the time might also have been influenced by more than a general malaise, report the authors of a new paper published online January 24 in Medical Humanities . [More]

With millions of birds descending on Delaware Bay during migration, the propensity for bird flu (H5N1) to spread among flocks--and potentially among humans --has been a pressing concern. And as animals, from gray whales to monarch butterflies make epic treks of thousands of kilometers each year, the role of these travelers in spreading highly pathogenic diseases along the way has been a key question for ecologists and epidemiologists alike. [More]

Editor's note: The article originally appeared in the February 11, 1911 issue of Scientific American.

February 1961

Protein Structure [More]

Obesity is a national health crisis--that  much we know. If current trends continue, it will soon surpass smoking in the U.S. as the biggest single factor in early death, reduced quality of life and added health care costs. A third of adults in the U.S. are obese, according to the Centers for Disease Control and Prevention, and another third are overweight, with Americans getting fatter every year. Obesity is responsible for more than 160,000 “excess” deaths a year, according to a study in the Journal of the American Medical Association . The average obese person costs society more than $7,000 a year in lost productiv­ity and added medical treatment, say researchers at George Washington University. Lifetime added medical costs alone for a person 70 pounds or more overweight amount to as much as $30,000, depending on race and gender.

All this lends urgency to the question: Why are extra pounds so difficult to shed and keep off? It doesn’t seem as though it should be so hard. The basic formula for weight loss is simple and widely known: consume fewer calories than you expend. And yet if it really were easy, obesity would not be the nation’s number-one lifestyle-related health concern. For a species that evolved to consume energy-dense foods in an environment where famine was a constant threat, losing weight and staying trimmer in a modern world of plenty fueled by marketing messages and cheap empty calories is, in fact, terrifically difficult. Almost everybody who tries to diet seems to fail in the long run--a review in 2007 by the American Psychological Association of 31 diet studies found that as many as two thirds of dieters end up two years later weighing more than they did before their diet.

Doing surgery in a tent on a tropical island is harder work than you’d think. It gets so hot that the sweat trickles from your surgical cap into your eyes, and when it rains on the tarp roof you can’t hear what your anesthetist is saying. I know this because I’ve worked on spay and neuter projects in the South Pacific, where I’ve gone with teams of veterinarians and volunteers to sterilize as many dogs as fast as we can.

Then, on my way to the airport to go home I’d see all the dogs we hadn’t caught, too many of them pregnant or about to be. With some quick mental math I realized that all our efforts would be negated in a year--litters of fertile pups would quickly replace the dogs we’d worked so hard to remove from the reproductive pool.

Researchers have engineered a new type of chicken that might help prevent the spread of bird flu --a worrisome virus that has already caused extensive economic harm on farms, especially in Asia, and that could lead to a pandemic in humans. [More]

As if it weren't bad enough that deadly prions can survive boiling and radiation, now comes word that aerosolized forms of the pathogen can enter the nose and find their way to the brain, with fatal consequences.

Throughout U.S. history there have been leaders, both Republicans and Democrats, who have supported the advancement of science and the protection of health and the environment and who have taken care to inform their policy decisions with the best scientific advice. After the midterm elections in November, it looked as though this tradition might take a backseat in the new Congress. For example, Representative-elect Jon Runyan, Republican of New Jersey, said in the aftermath of the election that to balance the federal budget one could cut “all the money we spend on frivolous research projects ... studying mating tendencies of fruit flies, stuff like that--is that really necessary?”

It is. The study of disease (for which fruit flies are essential tools), and scientific research in general, boosts economic growth, creates jobs and often ends up saving taxpayers money, as do improving infrastructure, supporting small farmers and promoting green energy. These are issues on which both parties could and should find common ground. Here is what we think should be top priorities of Congress and the Obama administration during the next two years.