Gee, and all this time I thought it was a mob hit
Volcanic Eruptions, Not Meteor, May Have Killed The Dinosaurs
ScienceDaily (Oct. 30, 2007) — A series of monumental volcanic eruptions in India may have killed the dinosaurs 65 million years ago, not a meteor impact in the Gulf of Mexico. The eruptions, which created the gigantic Deccan Traps lava beds of India, are now the prime suspect in the most famous and persistent paleontological murder mystery, say scientists who have conducted a slew of new investigations honing down eruption timing.
"It's the first time we can directly link the main phase of the Deccan Traps to the mass extinction," said Princeton University paleontologist Gerta Keller. The main phase of the Deccan eruptions spewed 80 percent of the lava which spread out for hundreds of miles. It is calculated to have released ten times more climate altering gases into the atmosphere than the nearly concurrent Chicxulub meteor impact, according to volcanologist Vincent Courtillot from the Physique du Globe de Paris.
Keller's crucial link between the eruption and the mass extinction comes in the form of microscopic marine fossils that are known to have evolved immediately after the mysterious mass extinction event. The same telltale fossilized planktonic foraminifera were found at Rajahmundry near the Bay of Bengal, about 1000 kilometers from the center of the Deccan Traps near Mumbai. At Rajahmundry there are two lava "traps" containing four layers of lava each. Between the traps are about nine meters of marine sediments. Those sediments just above the lower trap, which was the mammoth main phase, contain the incriminating microfossils.
Previous work had first narrowed the Deccan eruption timing to within 800,000 years of the extinction event using paleomagnetic signatures of Earth's changing magnetic field frozen in minerals that crystallized from the cooling lava. Then radiometric dating of argon and potassium isotopes in minerals narrowed the age to within 300,000 years of the 65-million-year-old Cretaceous-Tertiary (a.k.a. Cretaceous-Paleogene) boundary, sometimes called the K-T boundary.
The microfossils are far more specific, however, because they demonstrate directly that the biggest phase of the eruption ended right when the aftermath of the mass extinction event began. That sort of clear-cut timing has been a lot tougher to pin down with Chicxulub-related sediments, which predate the mass extinction.
"Our results are consistent and mutually supportive with a number of new studies, including Chenet, Courtillot and others (in press) and Jay and Widdowson (in press), that reveal a very short time for the main Deccan eruptions at or near the K-T boundary and the massive carbon dioxide and sulfur dioxide output of each major eruption that dwarfs the output of Chicxulub," explained Keller. "Our K-T age control combined with these results strongly points to Deccan volcanism as the likely leading contender in the K-T mass extinction." Keller's study was funded by the National Science Foundation.
The Deccan Traps also provide an answer to a question on which Chicxulub was silent: Why did it take about 300,000 years for marine species to recover from the extinction event? The solution is in the upper, later Deccan Traps eruptions.
"It's been an enigma," Keller said. "The very last one was Early Danian, 280,000 years after the mass extinction, which coincides with the delayed recovery."
Keller and her colleagues are planning to explore the onset of the main phase of Deccan volcanism, that is, the rocks directly beneath the main phase lavas at Rajahmundry. That will require drilling into the Rajahmundry Traps, a project now slated for December-January 2007/2008.
Keller and her collaborator Thierry Adatte from the University of Neuchatel, Switzerland, are scheduled to present the new findings on Tuesday, 30 October, at the annual meeting of the Geological Society of America in Denver. They will also display a poster on the matter at the meeting on Wednesday, 31 October.
Adapted from materials provided by Geological Society of America.
Volcano, meteor, volcano, meteor—either way they’re still dead, right? Unless this story is just a plant so we don’t worry about that big meteor headed this way.
This just in from our “We’re Smart and You’re Not” Department
Brain Activity Differs For Creative And Noncreative Thinkers
ScienceDaily (Oct. 29, 2007) — Why do some people solve problems more creatively than others? Are people who think creatively different from those who tend to think in a more methodical fashion?
These questions are part of a long-standing debate, with some researchers arguing that what we call “creative thought” and “noncreative thought” are not basically different. If this is the case, then people who are thought of as creative do not really think in a fundamentally different way from those who are thought of as noncreative. On the other side of this debate, some researchers have argued that creative thought is fundamentally different from other forms of thought. If this is true, then those who tend to think creatively really are somehow different.
A new study led by John Kounios, professor of Psychology at Drexel University and Mark Jung-Beeman of Northwestern University answers these questions by comparing the brain activity of creative and noncreative problem solvers. The study, published in the journal Neuropsychologia, reveals a distinct pattern of brain activity, even at rest, in people who tend to solve problems with a sudden creative insight -- an “Aha! Moment” – compared to people who tend to solve problems more methodically.
At the beginning of the study, participants relaxed quietly for seven minutes while their electroencephalograms (EEGs) were recorded to show their brain activity. The participants were not given any task to perform and were told they could think about whatever they wanted to think about. Later, they were asked to solve a series of anagrams – scrambled letters that can be rearranged to form words [MPXAELE = EXAMPLE]. These can be solved by deliberately and methodically trying out different letter combinations, or they can be solved with a sudden insight or “Aha!” in which the solution pops into awareness. After each successful solution, participants indicated in which way the solution had come to them.
The participants were then divided into two groups – those who reported solving the problems mostly by sudden insight, and those who reported solving the problems more methodically – and resting-state brain activity for these groups was compared. As predicted, the two groups displayed strikingly different patterns of brain activity during the resting period at the beginning of the experiment – before they knew that they would have to solve problems or even knew what the study was about.
One difference was that the creative solvers exhibited greater activity in several regions of the right hemisphere. Previous research has suggested that the right hemisphere of the brain plays a special role in solving problems with creative insight, likely due to right-hemisphere involvement in the processing of loose or “remote” associations between the elements of a problem, which is understood to be an important component of creative thought. The current study shows that greater right-hemisphere activity occurs even during a “resting” state in those with a tendency to solve problems by creative insight. This finding suggests that even the spontaneous thought of creative individuals, such as in their daydreams, contains more remote associations.
Second, creative and methodical solvers exhibited different activity in areas of the brain that process visual information. The pattern of “alpha” and “beta” brainwaves in creative solvers was consistent with diffuse rather than focused visual attention. This may allow creative individuals to broadly sample the environment for experiences that can trigger remote associations to produce an Aha! Moment.
For example, a glimpse of an advertisement on a billboard or a word spoken in an overheard conversation could spark an association that leads to a solution. In contrast, the more focused attention of methodical solvers reduces their distractibility, allowing them to effectively solve problems for which the solution strategy is already known, as would be the case for balancing a checkbook or baking a cake using a known recipe.
Thus, the new study shows that basic differences in brain activity between creative and methodical problem solvers exist and are evident even when these individuals are not working on a problem. According to Kounios, “Problem solving, whether creative or methodical, doesn’t begin from scratch when a person starts to work on a problem. His or her pre-existing brain-state biases a person to use a creative or a methodical strategy.”
In addition to contributing to current knowledge about the neural basis of creativity, this study suggests the possible development of new brain imaging techniques for assessing potential for creative thought, and for assessing the effectiveness of methods for training individuals to think creatively.
Yeah, nice little study with the EEG, the alpha and the beta and the Aha Moment. Too bad they didn’t work the paycheck factor into their study. As in, “who makes more?” Yeah, pal, I got your creative thinkin’ right here.
Headline of the day
Hunter recovering after being shot by dog
(AP and MSNBC)
So, you ask, what does a slow news day look like in science land?
Condiments Can Take Food From 'Blah' To 'Ahh' And Add Nutritional Value
ScienceDaily (Oct. 27, 2007) — With the right choice of condiments, seasonings or sauces, ordinary food can go from “blah” to “ahh” – with a boost in nutritional value.
“Think color,” said University of Arkansas dietetics professor Marjorie Fitch-Hilgenberg. “We eat with our eyes, and choosing colorful condiments can enhance the nutritional value of a routine food.”
Fitch-Hilgenberg uses the term condiments broadly to include all the “accompaniments” to food, such as seasonings, sauces, garnishes and marinades. All have their place in making food interesting and nutritious.
“Look at an average sandwich – some meat or cheese between slices of bread and slathered with mayonnaise,” Fitch-Hilgenberg said. “When you add dark leafy greens and tomatoes and replace the mayo, you can create a quick lunch with a serving or more of vegetables and little excess fat.”
Fitch-Hilgenberg’s research has shown that most people don’t notice the difference when nutrient-rich spinach replaces lettuce on burgers and subs. The resulting sandwich provides greater quantities of key nutrients, including vitamin C, vitamin A and folic acid.
There are more healthy alternatives to mayonnaise, beyond the low-fat and non-fat options on the grocery shelves. Fitch-Hilgenberg recommended looking for opportunities to replace mayonnaise with low-fat yogurt. For example, yogurt mixed with coarse mustard and dill is a tasty topping for grilled salmon steaks or salmon croquettes. She also uses a variety of mustards – Dijon, coarse-ground, spicy brown and wasabi – as low-calorie, high-flavor condiments.
“You don’t have to use mayo on a sandwich,” Fitch-Hilgenberg said. “You can spread some salsa, cranberry sauce, mango chutney or sauerkraut. They all add great taste and some extra nutrients without adding fat.”
She also looks for ways to add fruit to a meal by using it to flavor foods. For example, adding orange slices to cooked carrots can make the carrots more appealing to children and even more nutritious. Whipping fresh or frozen fruit in the blender makes a good topping for ice cream or a stir-in for plain yogurt.
“Condiments give you a chance to be adventurous and to taste other cuisines without leaving home,” Fitch-Hilgenberg said. “Chicken can be marinated in tandoori sauce, barbeque sauce or spicy brown mustard to take your meal to India, Texas or Germany.”
Two condiments from south Asia can be found in most groceries – curries and chutneys. Curry, which some studies have shown to contribute to healthy aging, does not have to be hot. A mild curry can be an intriguing addition to cooked carrots or rice and broccoli. Chutneys come in many different varieties, and Fitch-Hilgenberg advised reading the label before buying. Some contain fruit, such as mango chutney; others contain high levels of sodium.
Fitch-Hilgenberg cautioned that the downside to condiments is that they can add empty calories while disguising the flavor of foods. Marinades are a good way to flavor foods instead of spreading sauces on after cooking. Similarly, when a salad is tossed in a large bowl with a little dressing, the flavor of the greens is enhanced without being drenched in dressing that is high in fat and sodium. A plus, Fitch-Hilgenberg noted, is that it is much cheaper to use a little sauce or dressing in the kitchen than to put the bottle on the table.
“Healthy condiments can be used by everyone, whether for plain food or gourmet, carnivore or vegetarian,” Fitch-Hilgenberg said. “The condiments we choose are only limited by our imagination.”
If you’re waiting for me to drag out a “Hot today, chili tomorrow” joke, you’re wasting your time.
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