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Eat healthy for a super brain as you age PEOPLE WHO are having healthier diets with higher quantities of vegetables, fruits, fish, nuts, soy products intake are at a reduced risk of cognitive decline as they get older, says new research. The team from Ontario-based McMaster University tracked the health and habits of 28,000 people who were taking part in two international studies across 40 countries. Researchers found that of the 5,700 people with the healthiest diets, 14 per cent had developed cognitive decline. On the other hand, in the 5,460 people with the least healthy diets, about 18 per cent of them experienced cognitive decline. The unhealthy foods were red meat, deep-fried foods and sweets. It may not sound like a big difference but it is about a 24 per cent reduction in risk for the people on healthy diets. “The consumption of ‘healthy’ choices may be beneficial but the effect may be reduced with the consumption of ‘unhealthy’ choices,” Forbes reported.
Simple exercises can help control snoring, says research IF SNORING is hampering your partner’s sound sleep, simple mouth and tongue exercises can do wonders. Researchers have found that these exercises can reduce frequency of snoring by 36 percent and total power of snoring by 59 per cent. “This study demonstrates a promising, non-invasive treatment for large populations suffering from snoring, the snorers and their bed partners, that are largely omitted from research and treatment,” said Barbara Phillips, medical director, sleep laboratory at the University of Kentucky College of Medicine in the US.
Master protein that initiates organ formation found
Climate change threatens species As the planet warms it could drive to extinction as many as one in six animal and plant species, according to a new analysis
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n a study published Thursday in the journal Science, Mark Urban, an ecologist at the University of Connecticut, also found that as the planet warms in the future, species will disappear at an accelerating rate. “We have the choice,” he said in an interview. “The world can decide where on that curve they want the future Earth to be.” As dire as Urban’s conclusions are, other experts said the real toll may turn out to be even worse. The number of extinctions “may well be two to three times higher,” said John J. Wiens, an evolutionary biologist at the University of Arizona. Global warming has raised the planet’s average surface temperature about 1.5 degrees Fahrenheit since the Industrial Revolution. Species are responding by shifting their ranges. In 2003, Camille Parmesan of the University of Texas and Gary Yohe of Wesleyan University analyzed studies of more than 1,700 plant and animal species. They found that, on average, their ranges shifted 3.8 miles per decade toward the planet’s poles. If emissions of carbon dioxide and other greenhouse gases continue to grow, climate researchers project the world could warm by as much as 8 degrees Fahrenheit. As the climate continues to change, scientists fear, some species won’t be able to find suitable habitats. For example, the American pika, a hamsterlike mammal that lives on mountains in the West,
has been retreating to higher elevations in recent decades. Since the 1990s, some pika populations along the species’s southernmost ranges have vanished. Hundreds of studies published over the past two decades have yielded a wide range of predictions regarding the number of extinctions that will be caused by global warming. Some have predicted few extinctions while others have predicted that 50 percent of species face oblivion. There are many reasons for the wide variation. Some scientists looked only at plants in the Amazon while others focused on butterflies in Canada. In some cases, researchers assumed just a couple of degrees of warming while in others they looked at much hotter scenarios. Because scientists rarely were able to say just how quickly a given species might shift ranges, they sometimes produced a range of estimates. To get a clearer picture, Urban decided to revisit every climate extinction model ever published. He threw out all the studies that examined just a single species, such as the American pika, on the grounds that these might artificially inflate the result of his meta-analysis. (Scientists often pick out individual species to study because they already suspect they are vulnerable to climate change.) Urban ended up with 131 studies examining plants, amphibians, fish, mammals, reptiles and invertebrates spread out across the planet. He reanalysed all the
Hundreds of studies published over the past two decades have yielded a wide range of predictions regarding the number of extinctions that will be caused by global warming. Some have predicted few extinctions while others have predicted that 50 per cent of species face oblivion data in those reports. Overall, he found that 7.9 per cent of species. were predicted to become extinct from climate change. Estimates based on low levels of warming yielded much fewer extinctions than hotter scenarios. By his calculation, with an increase of 3.6 degrees Fahrenheit in surface temperature, 5.2 per cent of species would become extinct. At 7.7 degrees, 16 percent would. Urban found that the rate of extinctions would not increase steadily, but would accelerate if temperatures rose. Richard Pearson, a biogeographer at University College Lon-
don, called the new meta-analysis “an important line in the sand that tells us we know enough to see climate change as a major threat to biodiversity and ecosystems.” But he said that Urban was likely underestimating the scale of extinctions. The latest generation of climate extinction models are more accurate, Pearson said: sadly, they also produce more dire estimates. Wiens also noted that the tropics have been underrepresented in climate extinction studies. In Urban’s meta-analysis, 78 studies focused on species in North America and Europe while only seven came from South America. Yet when Urban combined all the data from South American studies, he found that 23 percent of species were at risk of extinction. In North America, by contrast, only 5 percent faced extinction. What makes this imbalance all the more glaring, Wiens said, is the fact that most of the planet’s species live in tropical forests such as the Amazon. If climate extinction research took tropical diversity into account, the planet’s overall risk would be much higher. Urban acknowledged that his meta-analysis is far from the final word. “This is a summary of the best information we have right now,” he said. As predictions improve, Urban said, they will allow conservation biologists to pinpoint the species at greatest risk of extinction and help plan strategies to save them. -Carl Zimmer/The New York Times News Service
RESEARCHERS have identified the “master” protein that directs the development of multi-cellular animals One of developmental biology’s most perplexing questions concerns what signals transform masses of undifferentiated cells into various organs. The new research provides evidence that it all begins with a single “master” growth factor receptor that regulates the entire genome. At the centre of the discovery is a single protein called nuclear Fibroblast Growth Factor Receptor 1 (nFGFR1). “FGFR1 occupies a position at the top of the gene hierarchy that directs the development of multicellular animals,” said study author Michal Stachowiak from University at Buffalo in the US. The FGFR1 gene is known to govern gastrulation, occurring in early development, where the threelayered embryonic structure forms. -IANS