Carbon dioxide, methane levels in atmosphere increase Atmospheric levels of carbon dioxide, the principal heat-trapping gas, are continuing to rise at an accelerating rate, the National Oceanic and Atmospheric Administration has reported. And after a decade of stability, levels of an even more potent heat-trapper, methane, rose as well. The agency said atmospheric levels of carbon dioxide reached nearly 385 parts per million last year, up from 280 in 1850 and an increase of 2.6 parts per million from 2006, chiefly from the burning of fossil fuels. The methane situation is less clear. Methane is produced naturally by swamps but also by activities including burning fossil fuels. The issue is important because climate experts have long worried that if Arctic permafrost thaws, the process would release potentially catastrophic amounts of methane into the atmosphere. In a statement, the agency said the most likely causes of the methane increase were economic development in Asia and emissions from Arctic wetlands. It said it was “too soon to tell” if the increase signals an Arctic thaw. The bumblebee takes over The bumblebee and other native wild bees are proving important in the garden now that the population of honeybees in the US is in such decline — down to 2.4 million colonies last year from 5.5 million in 1945, according to the US Department of Agriculture, due mainly, scientists say, to mites infesting the hives and, lately, to a mysterious epidemic called colony collapse disorder. Native bees pollinate everything from pear and cherry trees to blueberries, tomatoes and eggplant. They are also fascinating to watch. But native bees are on the decline too. The European honeybee, Apis mellifera, was brought to the US by the colonists in the early 1600s to make honey. Until then, from the time the first flowering plant was pollinated by a bee 120 million years ago, native bees had been doing the job just fine. In fact, they are at least 10 times more efficient than honeybees. Native bees fly farther between flowers, thus doing a better job at cross-pollinating than do honeybees.Praise as good as cash to brainPaying people a compliment appears to activate the same reward centre in the brain as paying them cash, Japanese researchers said on Wednesday. Their study offers scientific support for the long-held assumption that people get a psychological boost from having a good reputation. “We found that seemingly different kinds of rewards are biologically coded by the same neural structure, the striatum,” said Dr. Norihiro Sadato of the Japanese National Institute for Physiological Sciences in Okazaki. His team studied 19 healthy people using functional magnetic resonance imaging. In one set of experiments, people played a gambling game in which they were told one of three cards would yield a payout. The researchers then monitored the brain activity triggered when the subjects got a cash reward. In a second set of experiments, people were told they were being evaluated by strangers based on information from a personality questionnaire and a video they had made. The researchers then monitored reactions to these staged evaluations—including when the subjects thought strangers had paid them a compliment. Both kinds of rewards triggered activity in a reward-related area of the brain.
