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This story is a supplement to the feature “So You Think You Can Dance?: PET Scans Reveal Your Brain’s Inner Choreography” which was printed in the July 2008 issue of Scientific American. To identify the brain areas that control dance, researchers first need a sense of how the brain allows us to carry out voluntary movements in general. A highly simplified version is presented here. Motion planning (left) occurs in the frontal lobe, where the premotor cortex on the outer surface (not visible) and the supplementary motor area evaluate signals (arrows) from elsewhere in the brain, indicating such information as position in space and memories of past actions....

Urban life can be trying—cars and buses honk, passersby jostle, concrete and brick win out over grass and trees. Researchers have known for decades that residents of densely populated areas have higher rates of mental illnesses, including anxiety disorders and schizophrenia. But do the brains of city dwellers function any differently from those of rural folk? Studies are showing that they do. German researchers recently asked subjects from large cities, small cities and the countryside to undergo a standard psychological stress test—doing arithmetic under time pressure—while having their brain imaged with functional magnetic resonance imaging....

André Mendonça pops open the spring-loaded door on the shoebox-sized trap and peeks inside. Two bulging, black eyes glare back at him. He pulls the trap off the tree limb and shakes the stunned, sopping wet creature into a clear plastic bag. “One more!” he says excitedly. The animal, a gracile mouse opossum (Gracilinanus agilis), has a long, pointy nose, adorable pink ears, and slender hairless legs. Mendonça, a postdoctoral researcher at the University of Brasília, weighs and measures the animal, clips its ears and adds two metal tags....

Suwan Jayasinghe has shown in the past that the same technology used in ink-jet printers can spray out living cells and thereby potentially allow scientists to print new tissue. Now he has refined the technique down to the smallest scale, using electrospinning to weave polymer nanofibers no bigger than the cells they encase–and doing the constituent cells no harm. The process could enable the creation of living microfibers for such medical applications as creating scaffolds for the regrowth of damaged tissue....

Most paragons of architectural greatness distinguish themselves by an ability to stand out from their surroundings. The American Institute of Architects, by contrast, has just recognized a handful of buildings for their capacity to blend in. This week, the AIA’s Committee on the Environment (COTE) chose 10 structures that contribute more to the environments in which they dwell than they remove. They all have a few things in common: First, winning structures are designed with the natural environment in mind: the buildings, as examples, recycle wastewater and replace non-permeable ground and roof coverings, like asphalt, with soil and native vegetation....

Scientists are hoarding data on global temperatures, in case President-elect Donald Trump tries to wipe it off government Web sites or block public access to it. Ahead of Trump’s inauguration the U.S. Department of Energy (DoE) has released stricter guidelines to protect scientists from government interference, and for many it feels like that safety net could not have come soon enough. Welcome to what many call Trump’s post-fact presidency. Studies and evidence do not seem to sway him, but climate change remains a stubborn thorn in his side....

ALBUQUERQUE—Because forests can lock away carbon in their woody trunks, planting vast swaths of trees on barren land could provide a means for countries to mitigate their carbon emissions. But a comprehensive new analysis warns that pine plantations can rapidly deplete the soil of its nutrients—and carbon—thereby reducing the benefits. “It’s a tough balancing act,” says ecologist Sean Berthrong of Duke University. “Plantations are a usable but imperfect tool for carbon sequestration....

Nearly 500 years after Juan Sebastián Elcano completed the first circumnavigation of the globe using nothing but renewable power, Swiss engineer Raphael Domjan and French sailor Gerard D’Abouville are preparing to repeat Elcano’s journey in an all-electric boat powered by the energy gathered by 470 square meters of solar panels. Unveiled for the first time in a ceremony at a shipyard in Kiel, Germany, last week, their vessel is a catamaran made entirely out of the same kind of carbon-fiber composites that make modern airplane wings strong yet light....

Scientists have been trying to answer the question of whether marine protected areas, where sharks and their prey are off-limits to fishermen, are indeed home to more sharks than non-protected areas of the ocean. But how to monitor an environment where humans can spend only a few hours at a time? Researchers from New York’s Stony Brook University solved this problem by setting up 200 baited underwater video cameras, nicknamed “chum cams,” to count Caribbean reef sharks (Carcharhinus perezi) inside and outside marine reserves on a reef in the Caribbean Sea....

The most common way of fighting diseases like malaria, dengue fever, and West Nile today is to try to wipe out the mosquitoes carrying them and treat those who have been infected. Now there’s an alternative on the horizon that promises to be safer and cheaper by zapping the germs while sparing the mosquitoes. The technology is hidden in an artificial flower designed to attract mosquitoes and treat them with pathogen-killing drugs that allow the insects to live and continue to perform important functions such as pollinating flowers and serving as food for animals and other insects....

By Matt KaplanThe health of amphibians is commonly used to give a rough assessment of pollution levels in an area, but an analysis of more than 20,000 toxicity studies now suggests that these creatures are relatively resilient and not well suited to the task.The finding could have a significant effect on the way that the environment is assessed. Conventional wisdom suggests that if an amphibian population is thriving, the area is probably clear of pollutants....

Can one neuron release more than one neurotransmitter? —Marvin Shrewsbury, Wailuku, Hawaii Rebecca Seal, a neuroscientist at the University of California, San Francisco, replies: WHEN DISCUSSING neurotransmitters, most people think of the classical neurotransmitters, such as dopamine and serotonin—the primary chemical messengers used by neurons to communicate with one another and with other types of cells. In the early 20th century physiologist Sir Henry Dale hypothesized that an individual neuron releases the same classical neurotransmitter from all its axons, the spindly branches that jut out from the main cell body....

An unofficial IE mascot in Singapore demonstrates that people still love Microsoft’s browser after all these years. (Credit: Screenshot by Seth Rosenblatt/CNET) Remember Clippy, the helpful, googly-eyed paperclip? Microsoft hasn’t had a lot luck with anthropomorphic characters. But that’s not going to stop Sailor IE from lending a hand to the launch of Internet Explorer 11 for Windows 7 on Thursday. Known as Inori Aizawa, the Microsoft Singapore character was created to draw local attention to the new IE, as well as Windows Phone-powered Nokia phones and Surface tablets, from attendees of the currently-underway Anime Festival Asia....

DURBAN, South Africa—My share of the carbon dioxide my flight to Johannesburg emitted over 15 hours amounted to 1,391.3 kilograms, according to the helpful information provided by South African Airlines. Add a dollop of 53.8 kilograms of CO2 for the jet jaunt to Durban and you can see that the aviation industry—and the Durban climate talks—have an emissions problem. In fact, flying now accounts for some 2 percent—and growing fast—of global greenhouse gas emissions, although the industry has pledged to stop that growth by 2020....

Dear EarthTalk: I’ve heard that cars can be modified to run on water. How is this possible? – Diane McMorris, Rockport, ME There are a number of online marketing offers of kits that will convert your car to “run on water,” but these should be viewed skeptically. These kits, which attach to the car’s engine, use electrolysis to split the water (H2O) into its component molecules—hydrogen and oxygen—and then inject the resulting hydrogen into the engine’s combustion process to power the car along with the gasoline....

All science begins in a star trek mode: go where no one has gone before and discover new things without knowing in advance what they might be. As researchers complete their initial surveys and accumulate a long list of questions, they shift to a Sherlock Holmes mode: formulate specific hypotheses and develop ways to test them. The exploration of Mars is now about to make this transition. Orbiters have made global maps of geographic features and composition, and landers have pieced together the broad outlines of the planet’s geologic history....

BOULDER, Colo. – As the West has warmed and dried over the past 30 years, headlines describing fire season have grown ever more apocalyptic: “epic” dryness, “monster” fires, new records for damage and devastation. This year is no exception. The Waldo Canyon Fire has incinerated hundreds of homes in Colorado Springs, and every indication points to another big, early start to the wildfire season. Recent research, however, suggests these severe conflagrations could be a prelude....

Google plans to invest more than $1 billion in a new fleet of satellites that will expand Internet access to unconnected regions of the world. The company’s decision to purchase 180 small, high-capacity satellites is just the first step in a project that could cost the search giant over $3 billion, reported The Wall Street Journal. The project’s price tag will depend on whether the company decides to embark on a second phase of the project, which would double the number of satellites needed, Google insiders told the WSJ....

Editor’s Note: Maria Estevez was 62 years old in 2006 when she participated in the second psilocybin study conducted by Roland Griffiths, a co-author of the Scientific American article on hallucinogens. The inspiration she derived from these experiences prompted her to write a yet-unpublished book about how it affected her life both during the study and afterward. In this excerpt from One Kind of Knowing, quoted with permission, she recounts what occurred during the second and most intense of four experiences with the drug....

Western cultures have long cherished the notion that all people are created equal. But in the real world, our lives are not balanced with equal opportunities and resources. This distinction was noted mordantly in 1894 by author Anatole France, who wrote that “the law, in its majestic equality, forbids the rich as well as the poor to sleep under bridges, to beg in the streets, and to steal bread.” The rich, of course, need none of these things, whereas the poor often have little choice....