Health & Science
Journey to a strange, undersea world; Sharks broaden gene pool; All calories count; Arguments worth having
Journey to a strange, undersea worldIt’s an alien world, teeming with bizarre creatures unlike any previously seen. To find it, scientists didn’t travel to another planet; they sent a first-ever expedition of submersibles to hydrothermal vents at the bottom of the Southern Ocean, near Antarctica. There they found “a hot, dark, lost world’’ populated by dozens of strange new species that are “almost like a sight from another planet,” Oxford University zoologist Alex Rogers tells Wired.co.uk. The vents—which spew chemicals from deep underground at temperatures of up to 720 degrees—are home to hairy-chested yeti crabs, pale octopuses, and seven-armed starfish, among other wonders. Researchers have explored hydrothermal vents in the Pacific and Atlantic oceans before, but the Southern Ocean vents appear to support a completely different ecosystem, proving that such habitats are more diverse than previously thought. At hydrothermal vents, where there’s no sunlight to fuel photosynthesis, creatures get their energy from the hot water and stew of chemicals that flow through the fissures in the seabed. Scientists say studying these regions is yielding new insight into how life might arise in the harsh environments of other planets.
Sharks broaden gene poolTwo different species of sharks have been interbreeding off the coast of Australia—creating the first hybrid sharks ever seen. Australian blacktips, which live in tropical waters, have been mating with common blacktips, which are able to tolerate lower temperatures, producing offspring that can tolerate a broader range of water temperatures and geographical habitats. The discovery of these hybrids is like “catching evolution in action,’’ Bob Hueter, a shark expert at the Mote Marine Laboratory, tells MSNBC.com. Hybridization may be one way Australian blacktips are adapting to climate change; their hybrid offspring can survive in colder waters than they can, so as ocean temperatures shift, they’ll have a wider range of habitat options. Overfishing may also have depleted both species’ populations, driving them together. So far, researchers have used genetic testing to identify 57 hybrid sharks, from multiple generations.
All calories countSome popular diets say you should eat lots of protein (and very little carbohydrates) to lose weight; others say you should load up on carbs, and avoid protein and fat. A new study shows that the amount of protein in any diet is less important than the total calories you consume. When it comes to how much fat your body stores, “you don’t fool nature by adding more or less protein,” obesity researcher George Bray of the Pennington Biomedical Research Center tells CNN.com. He and his colleagues fed three groups of sedentary volunteers 1,000 extra calories a day to make them gain weight. Each group’s meals contained a different proportion of protein. After eight weeks, the subjects had put on almost exactly the same amount of body fat. There was one important difference, however. The low-protein group gained less weight overall, but lost lean muscle. By contrast, the higher-protein groups added lean muscle in addition to fat, and amped up their metabolisms to burn additional calories. The study proves that if you eat more calories than you burn, no amount of protein will keep you from packing on fat. But as part of a low-calorie diet, high-protein foods could help you shed more weight in the long run.
Arguments worth havingParents who browbeat their kids into being obedient and agreeable may not be giving them the best preparation for the real world. A new study shows that encouraging teens to argue calmly and effectively against parental orders makes them much more likely to resist peer pressure. University of Virginia researchers observed more than 150 13-year-olds as they disputed issues like grades, chores, and friends with their mothers. When researchers checked back in with the teens two and three years later, they found that those who had argued the longest and most convincingly—without yelling, whining, or throwing insults—were also 40 percent less likely to have accepted offers of drugs and alcohol than the teens who had caved quickly. “We found that what a teen learned in handling these kinds of disagreements with their parents was exactly what they took into their peer world,” study author Joseph P. Allen tells NPR.org. The key to having a constructive debate with your kids, experts say, is listening to them attentively and rewarding them when they make a good point—even if you don’t end up reaching a mutual agreement. “Think of those arguments not as a nuisance,” Allen says, “but as a critical training ground” for wise, independent decision-making.