Energy efficiency is supposed to be the one thing everyone can agree on, the so-called "low-hanging fruit" in the fight against global warming. While politicians bicker over the actual greenhouse gas emissions that fuel climate change, at least we can feel good about driving efficient cars or using efficient light bulbs. Or can we? According to today's Science Times, the "rebound effect" may actually lead us to use more energy because we feel like we're saving so much of it.

The rebound effect can manifest itself in many ways. The owner of a hybrid car might be so enchanted with her gas mileage that she ends up driving twice as much, for example, or someone with a low-flow shower head may end up taking longer showers. And there's also an indirect rebound effect — if a consumer does save money from high-efficiency products, he may use that money to buy other things that require more greenhouse emissions, whether it's a new TV or a flight to Florida. If this rebound effect is high enough, it can lead to what's known as "backfire," or more net energy use than if the efficiency hadn't been improved. And as the Times points out, this concept isn't new: It's also called the "Jevons Paradox," named after a 19th-century economist who noticed that steam engines not only burned coal more efficiently, but also spurred so much economic growth that overall coal consumption went up. This effect has been largely ignored since then, and as energy efficiency now eclipses efforts to replace dirty fuels like coal with cleaner ones like wind and sunlight, the Jevons Paradox may be more relevant than ever — especially as large countries like China and India industrialize.

"Efficiency advocates try to distract attention from the rebound effect by saying that nobody will vacuum more because their vacuum cleaner is more efficient," explains a co-author from a recent study on energy efficiency. "But this misses the picture at the macro and global level ... When you increase the efficiency of a steel plant in China, you'll likely see more steel production and thus more energy consumption."

(Sources: New York Times, Encyclopedia of Earth)


Apples can do more than just improve your health — they might actually lengthen your life. That's according to a new study in the Journal of Agricultural and Food Chemistry, which found that eating apples can extend average life span by 10 percent. The study was conducted on fruit flies, but the insects are already used as stand-ins for humans in hundreds of research projects every year, the study's authors note.

The findings also support previous research that has linked eating apples to similar outcomes in other animals. One recent study, for example, showed that women who frequently ate apples had a 13 to 22 percent decrease in their risk of heart disease. This is apparently due to antioxidants in apples known as polyphenols, which counteract the effects of destructive substances in the body called free radicals. Free radicals are associated with aging as well as certain diseases such as cancer, and therefore can limit a person's (or a fruit fly's) life span. Antioxidants combat the damage done by free radicals, making antioxidant-rich foods like brightly colored fruits and vegetables — including apples — a powerful weapon in the fight against aging-related illnesses.

In the new study, Chinese University of Hong Kong professor Zhen-Yu Chen and his colleagues found that apple polyphenols went beyond merely prolonging the flies' average life span. They also helped preserve the insects' ability to walk, climb and move around, making them generally more physically fit as they aged. The polyphenols also reversed the amounts of various biochemical markers found in elderly flies that are typically seen as signs of age-related deterioration. In other words, an apple a day might help you live longer and keep the doctor away.

(Source: ScienceDaily)


It's already hard for some people to accept that chimpanzees are highly intelligent, so imagine their horror at learning this: A new study reports that elephants not only belong to an "elite group" of smart, socially complex animals, but in some cases their problem-solving skills eclipse even those of chimps. "As humans, we like to show that we're unique," lead author Joshua Plotnik tells the BBC, "but we're repeatedly shot down."

In humanity's latest humbling, Plotnik and his colleagues showed that elephants aren't as hard-headed as they might seem — in fact, they're well-aware when they need a helping hand. The researchers had already trained a group of elephants how to pull a floating platform toward them using a rope, but for this experiment they introduced a twist: The platform still held food as a reward, but suddenly the rope was looped around the platform like a belt, so that tugging on one end simply pulled out the rope without budging the platform. To successfully retrieve their reward, two elephants would have to work together, each pulling one end of the rope so it couldn't come loose from the platform. Not only did they realize this, but they mastered the task with surprising ease. "When we released one elephant before the other, they quickly learned to wait for their partner before they pulled the rope," Plotnik tells the BBC. "They learned that rule quicker than chimps doing the same task." One young elephant learned the rule so well, in fact, that she simply stood on her end of the rope, letting her partner do all the work.

By better appreciating elephant intelligence, humans become better able to co-exist with them in the wild, the researchers argue. "The more we can understand about their intelligence, the better we can develop solutions to things like human-elephant conflict," Plotnik says. "So when the animals are raiding crops, we need to think of solutions that are based on the reasons why, and that benefit elephants as well as people."

(Sources: BBC News, Wired, PhysOrg)


Spring has apparently not yet sprung in New England, where a ferocious snowstorm dumped more than 2 feet of snow Monday, extending what has already been an unusually extreme winter across North America. Up to 30 inches of snow fell in some areas of northern New England and upstate New York, while heavy rains triggered dangerous flooding in Canada. 

As National Weather Service meteorologist Bruce Taber tells the AP, the storm was caused by two very different air masses crashing together. "We had almost a tropical air mass across southern New England that was trying to push north at the same time a polar air mass was trying to push south," Taber says. "It was that battleground that created this intense snowfall." And "battleground" is an apt metaphor for the scene in many places — a 10-mile stretch of Interstate 89 in northern Vermont was closed for hours as blowing snow triggered whiteout conditions, for example, while a work crew in southern Vermont had to stop repairing downed power lines because of ice-covered trees crashing down all around them. At the storm's peak, more than 50,000 power outages were reported, most of them in Albany, N.Y., but also many in Vermont. 

As with other recent storms this winter, it wasn't just the snow that wreaked havoc. Freezing rain fell in several states, making road travel treacherous, while downpours also spurred floods and mudslides from Connecticut to western Canada. "There's a little bit of everything," says NWS meteorologist Margaret Curtis in Maine, parts of which received 18 straight hours of rain followed by sleet and heavy snow. 

(Sources: Associated Press, National Weather Service)


An Italian volcano erupts, Monty Python castle benefits bats, and more.

Russell McLendon

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Photo (energy-efficient dishwasher): ZUMA Press

Photo (red delicious apple): U.S. Department of Agriculture

Photo (elephants bathing): Lonely Planet Images

Photo (snowfall on March 7, 2011): zaui/Flickr

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