Wednesday, September 28, 2011
Sunday, September 25, 2011
Researchers made quite a find this week in Utah: a new species of raptor dinosaur. The ancient creature, a meat-eater, was small and fast, with talon-like toes.
"These animals were incredibly fast, incredibly intelligent and some of them wielded very significant claws and sharp teeth," Dr. Lindsay Zanno of the New University of Wisconsin tells NPR's Scott Simon. Zanno led the dig team that made the discovery.
Zanno named the species Talos Sampsoni afterher friend and colleague, Dr. Scott Sampson, also known as "Dr. Scott" on the television series, Dinosaur Train. Talos Sampsoni was feathered and about 5-feet long and about 2-and-a-half feet at the hips, Zanno says. "Definitely an overgrown vicious Labrador retriever-sized animal," she says.
Michael Knell, a graduate student at Montana State University, actually made the discovery. Knell had been hunting the Badlands in Southern Utah for fossilized turtles. "He turned the corner and found one of the most amazing raptor-dinosaur specimens we have from the late Cretaceous in North America," Zanno says.
The bones were intact and, in the ground, looked the way they would have in life — a discovery, she says, that is fairly rare in North America.
"Most dinosaur specimens that we have have been laying out on the surface for a long time and the bones have become scattered," Zanno says.
The discovery is significant not because it reveals anything new about the biology of these animals, Zanno says, but rather because it's a piece of the puzzle researchers had speculated about but never confirmed. Zanno says that footprint evidence suggested that the specialized talon on the foot of the raptor dinosaur wasn't used for walking and was regularly put in harm's way. But this kind of evidence is ambiguous.
"Finding Talos was something we were all waiting for and was confirmation we'd been speculating about for a long time," she says.
The dinosaur will soon go on display at the Utah Museum of Natural History in Salt Lake City.
As for Knell? "He's still plugging away at his degree and hopefully getting some good fanfare out of his important discovery," Zanno says.
September 24, 2011
Thursday, September 22, 2011
A half-billion-year-old fossil "compound" eye (left)—likely from an ancient shrimplike predator—was surprisingly advanced for its time and gave its owner vision comparable to those of modern insects, such as the robber fly (right), a new study says.
The fossil eyes were found on Kangaroo Island (map) in southern Australia and are estimated to be about 515 million years old.
Unlike human eyes, which have only one lens, the compound eyes of arthropods—including insects and crustaceans—have hundreds or even thousands of separate lenses.
"The owner of a compound eye sees the world as a series of dots. Each dot is generated by one lens in the eye, so the more lenses you have, the more detail you see the world with," explained Michael Lee, an evolutionary biologist at Australia's University of Adelaide.
"If you have very few lenses, you're going to see the world with very few dots—everything will look like very bad newsprint."
The research by Lee and his team was detailed in the June 30 issue of the journal Nature.
The links between red wine and longevity aren't nearly as strong as they once seemed, according to new research in the journalNature. In fact, the research calls into question the whole mechanism used to explain wine's power to extend life.
This all has to do with some natural proteins called sirtuins. (That's pronounced sir-TWO-ins in American English, in case you're reading this out loud at a bar.) Yeast carry a version. So do worms, mice and people.
About 10 years ago, scientists noticed that an extra helping of sirtuins seemed to help living things live longer. And there was some evidence that a substance in red wine called resveratrolcould crank up sirtuin production.
Then, in 2006, a Harvard researcher named David Sinclairreported that obese mice that got doses of resveratrol lived longer than fat mice who didn't — about 30 percent longer.
The study was published in Nature and reported by media around the world. The assumption was that what was good for fat mice would also be good for thin animals, or even people.
As a result, sales of red wine jumped and a biotechnology company founded by Sinclair and others to develop the substance as a drug became extremely valuable. In 2008, the drug company GlaxoSmithKline bought Sinclair's company, Sirtris, for $720 million.
But over the years, some scientists had begun to question whether sirtuins really were the key to extending life. Some studies of sirtuins even suggested they didn't affect lifespan.
And this week, Nature published research that offers a strong rebuttal to the idea.
The centerpiece is a study by a team including David Gems, a geneticist who studies aging at University College London. The team attempted to replicate some of the early experiments with worms and fruit flies.
"We could create worms and flies with elevated levels of this sirtuin protein," Gems says. But, he adds, "They were not long-lived."
The reason that animals in the original studies lived longer, Gems says, is that they had genetic mutations that had nothing to do with sirtuins. And this puts the proteins in a very different light, he says.
"What this should do is act as a cap on the idea that they are important in the biology of aging," Gems says.
It also "blows apart" the idea that scientists have figured out the nature of aging, says Scott Pletcher a geneticist at the University of Michigan who wrote an article that accompanies the new Sirtuin research in Nature.
Some of the researchers who did the early work on sirtuins disagree with that conclusion. But they concede that there were genetic changes in some of the animals in those early studies.
"One strain did have a problem and so we redid everything," says Leonard Guarente from MIT, who is on the science advisory board of Sirtris.
When that strain was removed from the results, Guarente says, sirtuins still produced a life-extending effect, but it was "in the 10 to 15 percent range rather than the 30 percent range."
People shouldn't give up on sirtuin drugs though — especially people who eat too much, or have a high-fat diet, Guarente says.
He says a primary goal of the research on sirtuins was to develop drugs that could prevent diseases associated with aging, like diabetes and heart disease. As a result, many of the experiments have looked at drugs that affect sirtuins in animals that are obese or eat a lot of fat.
And those studies show that sirtuin drugs do make a difference, Guarente says.
"We're treating diseases," he says. "We're not treating aging itself."
Other scientists agree that sirtuin drugs do show promise in preventing diseases in high-risk individuals. In theory, that could mean drugs that would let you eat fatty foods or get fat without putting your life at risk.
But it's unlikely that red wine will help by activating sirtuins.
The new research in Nature includes an experiment that tested the supposed active ingredient in red wine: Resveratrol. The researchers found that resveratrol had no effect on sirtuins.
We have no doubt we haven't reached the bottom of the bottle on this one.
September 21, 2011
A powerful typhoon slammed into Japan Wednesday, halting trains and leaving 13 people dead or missing in south-central regions before grazing a crippled nuclear plant and heaping rain on the tsunami-ravaged northeast.
But the typhoon brought new misery to the northeastern region already slammed by the March 11 earthquake and tsunami, dumping up to 17 inches of rain in some areas.
Authorities warned of a high risk of mudslides in that region. Hundreds of tsunami survivors in government shelters in the Miyagi state town of Onagawa were forced to evacuate for fear of flooding.
More than 200,000 households in central Japan were without electricity late Wednesday. Police and local media reported 13 people dead or missing in southern and central regions, many of them believed swept away by rivers swollen with rains.
The storm, packing sustained winds of up to 100 mph, made landfall in the early afternoon near the city of Hamamatsu, about 125 miles west of Tokyo. The fast-moving storm went past the capital in the evening and then headed up into the northeast, where it was losing strength.
At the Fukushima plant, engineers are still working to stabilize the reactors six months after three of them melted down when the tsunami disabled the plant's power and back-up generators.
"The contaminated water levels have been rising, and we are watching the situation very closely to make sure it stays there," Matsumoto told reporters.
As the storm headed further into the north, it triggered landslides in parts of Miyagi state that already were hit by the March disasters. The local government requested the help of defense troops. Dozens of schools canceled classes.
The disaster-struck region had a chilling reminder of its earlier disasters when a magnitude-5.3 earthquake struck late Wednesday just south of Fukushima in the Ibaraki state. Officials said the temblor posed no danger to the plant, and that it did not cause any damage or injuries in the region.
Heavy rains prompted floods and caused road damage earlier in dozens of locations in Nagoya and several other cities, the Aichi prefectural (state) government said.
Parts of Japan's central city of Nagoya, about 170 miles west of Tokyo, were flooded near swollen rivers where rescue workers helped residents evacuate in rubber boats.
Police in nearby Gifu prefecture said a 9-year-old boy and an 84-year-old man were missing after apparently falling into swollen rivers.
More than 200 domestic flights were canceled and some bullet train services were suspended.
A typhoon that slammed Japan earlier this month left about 90 people dead or missing,
Wednesday, September 21, 2011
The marine invertebrates called crinoids filled the seas during the Carboniferous period and even earlier. Their fossils are frequently found in limestone from the period, giving the Carboniferous the nickname the "Age of the Crinoids."