What dinosaurs ate - The belly of the beast

A chance discover y from China suggests some dinosaurs lived in trees

WHAT dinosaurs ate is, of course, a question as interesting and illuminating as what ate dinosaurs. In the case of one particular dinosaur, Microraptor, the matter was addressed in a presentation to the annual meeting of the Society of Vertebrate Palaeontology by Jingmai O'Connor of the Institute of Vertebrate Palaeontology and Palaeoanthropology, in Beijing.

Microraptor (see photograph) is one of many small, feathered dinosaurs found in what is now China that were alive during the Cretaceous period more than 66m years ago. Being feathered, it and its kind were cousins to birds. The actual split between the two groups, though, had happened much earlier, during the Jurassic period (the first known bird is Archaeopteryx, from 150m years ago), and by the late Cretaceous there were many species of bird around. What Dr O'Connor and her colleagues have found is the remains of one of those birds, of an as-yet-unidentified species, in the stomach of a specimen of Microraptor.

That is interesting. Discovering direct evidence of what a fossil animal ate, rather than having to infer it from details such as the shape of its teeth, is always valuable. But the find's true significance is a small detail of the prey's anatomy: the third toe of its foot. The size of the prey's third toe is important because, among birds, long third toes are helpful for grasping branches and perching in trees. Indeed, the trait is so useful for arboreal life that it is used by many avian palaeontologists to decide whether newly excavated species of fossil birds lived in trees or on the ground. And the last meal of this particular specimen of Microraptor did, indeed, have a long third toe.

That elongated toe suggests to Dr O'Connor that Microraptor, too, was arboreal, and hints that its feathers may have helped it to move through an environment where hops, jumps and flaps between branches were a regular part of its daily activity. Whether the first birds evolved from arboreal or terrestrial ancestors is a matter of lively debate among palaeontologists. A fossil formed so long after birds emerged does not, in truth, shed much light on that debate. But it does suggest feathers may have helped promote life in the trees, even for creatures that could not actually fly.

Source of Information : [The.Economist] Volume 401 Number 8759 Nov 12th - Nov 18th 2011

What ate dinosaurs? Old crocs

Even in their heyday, dinosaurs were not quite as dominant as popular myth makes th em out to be

0NE answer to the question, "What ate dinosaurs?" is, obviously, "Other dinosaurs." Theropod predators like Tljrannosaurus and Allosaurus loom large in the imagination of every lover of prehistoric monsters, and their animatronic fights with the likes of Diplodocus and Stegosaurus are the stuff of cliche. Science, though, tries to look beyond the obvious, and at this year's meeting of the Society of Vertebrate Palaeontology, held in Las Vegas, some of the speakers asked whether the top predators of the Mesozoic era really were all dinosaurs. Their conclusion was "no". Another group of reptiles, until recently neglected, were also important carnivores. And it is a group that is still around today: the crocodiles.

That the past role of crocodiles (or, strictly, crocodilians, since they came in many sizes and shapes, not all of which resemble the modern animals) has been underestimated was suggested a few years ago by Paul Sereno. Dr Sereno, a palaeontologist at the University of Chicago, uncovered a crocodile-dominated ecosystem from about 1oom years ago (the middle of the Cretaceous period), in what is now north Africa. Besides water-dwelling giants similar to (though much bigger than) today's animals, he found a range of forms including vegetarians and species that ran on elongated legs- more like dogs than crocodiles. That discovery has prompted other fossil hunters to look elsewhere. As a result, even the well-studied rocks of North America are revealing that dinosaurs did not have it all their own way in the ecosystems of the Mesozoic- as Stephanie Drumheller of the University of Iowa and Clint Boyd of the University of Texas at Austin explained to the meeting.

The Cretaceous equivalent of zebra and antelopes- the victim species in every wildlife documentary about the dramas of the African savannah- were herbivorous dinosaurs called ornithopods. Frequently, these were taken by theropods. But not always. When Ms Drumheller and Mr Boyd examined the bones of juvenile upperCretaceous ornithopods dug up in Utah they saw marks on one skeleton that looked suspiciously like those modem crocodiles inflict when biting and tearing at their prey. On examining these marks more closely, they found a crocodilian tooth stuck in one of them.


Crocodile tears
It was not a large tooth. Its size suggests the animal which made it was no more than a metre and a half (about 5 feet) long. Such a predator would have been unable to take on an adult ornithopod. Nevertheless, this tooth is the first unarguable proof that crocodilians did indeed snack on dinosaurs. Moreover, it helps to confirm suspicions that the other crocodile-bite-like marks that Ms Drumheller and Mr Boyd have discovered really are what they look like. By combining that with an analysis of the whole site, the two researchers argue that what they have discovered is a dinosaur nesting ground that was being raided by crocodilians.

Such suspicions have been aroused before. Other sites in Utah are known to be
dinosaur nesting grounds, since eggs are found there. Crocodilian bones frequently turn up at such sites. Ms Drumheller and Mr Boyd, however, seem to have nailed the connection down. Juvenile dinosaurs, at least, were indeed the prey of crocodilians. But what about adults?


More than mere morsels
To investigate that question, Martin Lockley at the University of Colorado, Denver, and Spencer Lucas of the New Mexico Museum of Natural History and Science, turned to one of the most famous fossil phenomena on the planet- the dinosaur freeway that runs through Colorado, New Mexico, Kansas and Oklahoma. This collection of tracks, scattered over several sites of the same age along the coast of an inland sea, is thought to mark an ancient migration route. The traces of more than 1,380 individual animals can be distinguished. Most, but not all, were omithopods. Some were small carnivorous dinosaurs-the sort that might pick off young stragglers in the way that the crocodilians identified by Ms Drumheller and Mr Boyd did. But there is, Dr Lockley and Dr Lucas realised, something missing from the picture. When they looked for traces of big predatory dinosaurs, they found none.

That is ecologically absurd. Unless, of course, the top predator of the system- the one that could hunt down adult ornithopods-was not a dinosaur at all. And, when Dr Lockley and Dr Lucas re-examined the tracks they found that that was exactly what was going on. Instead of therepod footmarks, they found those of crocodilians. More than a quarter of the places where the dinosaur freeway sur- faces have yielded signs of crocs. And they
were big: sometimes more than four metres long. That is certainly large enough to
take on an adult ornithopod. Such megacrocs, then, could easily have acted as top predators in this ecosystem. But that does not completely explain the absence of theropod tracks. Modem migrating herbivores fall victim to many sorts of carnivore: big cats, wolves and hyenas, to name but three. The marshy conditions of the dinosaur freeway (the reason its footprints formed, and have survived) may, though, have favoured crocodilians over predators that had evolved on drier land. In that sort of environment even a big theropod would constantly have been looking over its shoulder. Perhaps the real reason why they did not plant their footprints on the dinosaur freeway is that they might have ended up as prey, as well.

Source of Information : [The.Economist] Volume 401 Number 8759 Nov 12th - Nov 18th 2011

Cristina the alchemist BUENOS AIRES

Argentina is trying to build a scientific establishment

SOUTH AFRICA is not the only middleincome country which aspires to join the world's scientific powers (see previous story). Argentina would like to as well. The place is proud of its three Nobel science prizes-the largest haul of any Latin American nation-even if the most recent was awarded in 1984. But many researchers fled in the 1990s, when budgets were slashed. Now the government is trying to attract them back, and to encourage younger talent to consider a scientific career.

When Nest or Kirchner, the predecessor and late husband of the current president,
Cristina Fermindez, took office in 2003, Argentina was spending just 0-41% of its GDP on research and development (R&D). Now, that figure is 0.64%. (Brazil, by comparison, spent 0.95% in 2003 and 1.18% in 2009.) Kirchner raised researchers' salaries, launched a scheme to repatriate departed scientists and gave tax breaks to software companies. Ms Fernandez followed suit by creating a science ministry and putting a biologist, Lino Baraiiao, in charge of it. She also increased grants to firms that try to develop new products. Many of the Kirchners' critics were sceptical, seeing the ministry either as a political marketing ploy or as a soft touch for lobbyists seeking unjustified subsidies.
But the strategy seems to be working. With help from the Inter-American Development Bank the government has, since 2004, lured back 854 expatriate scientists. It has done so by providing new laboratories and equipment for them, moving their families, and forking out extra money for their salaries. As a consequence, according to Dr Baraiiao, Argentine researchers have published179 articles in leadingjournals in the past decade, compared with just 30 in the1990s.

Most of the returners are academics. But commercial science has benefited, too. In dear, a joint public-private biotechnology-research centre based in Santa Fe, recently worked out how to transfer a gene for drought resistance from sunflowers to crops such as maize, soya beans and wheat.

That can increase yields in droughts by up to 40%. And the government has also doled out $54m in grants for the development of products that include coagulant factors to treat haemophilia, transgenic cattle which secrete valuable hormones in their milk, and better ways of probing for oil deposits.

Help for high-tech innovation comes in other forms, too. The state offers, for example, to pay the cost of patenting inventions in foreign jurisdictions and of hiring lawyers to defend those patents. It also acts as a headhunter for information-technology firms seeking employees with PhDs, and will pay part of the salaries of such recruits. None of these programmes has faced allegations of corruption. Whether all this activity will have the effect of stimulating high-tech industry, as Ms Fernandez hopes, remains to be seen. Argentine scientists are happy to take taxpayers' money but according to Luis Dambra, a professor at the IAE business school in Buenos Aires, they look down their noses at the idea of actually getting their hands dirty by going into industry. Mr Dambra, though, says industry is equally to blame. In 2009 (the latest year for which data are available), only 21% of Argentine R&D was paid for by the private sector, compared with 44% of Brazil's. Firms that might recruit academic scientists often do not see the point. Even those that do may struggle to accommodate people with a non-commercial background into the business world.

Attitudes can change, of course. In the 1980s many British academics were as snobbish about commerce as Argentina's are now. These days, Britain's top universities are gung-ho for spin-outs and the revenue they can provide. But it takes time and consistent policy to make such changes and Argentina is notorious for sudden alterations in the political weather. That makes the country a perilous place to invest, whatever the current climate.

Source of Information : The Economist Volume 401 Number 8758 Nov 05th - Nov 11th 2011

Better Health for the Uncounted Urban Masses

Most of the people who moved to London, New York City, Chicago, Berlin and other big cities during the 19th century traded away their health to make better wages. Crowding, unsafe drinking water, bad sanitation, harsh working conditions and industrial pollution made them sicker than their cousins back home in the countryside and shortened their life spans. But starting in the middle decades of the 1800s, government reforms and urban leaders began turning the health of these cities around by investing in water, sanitation, waste removal, education and more. Today affluent cities are among the healthiest places to live. Even in many middle-income countries urban dwellers go about their lives largely unthreatened by the classic epidemics.

Yet the 800 million to 900 million people living in the informal settlements that make up modern-day slums still await such miracles. They suffer the effects of overcrowding, contaminated water and lack of affordable health care. In many of these places one in six children dies before the age of five, and life expectancies are less than half as long as those in the healthiest cities. The situation will not get better until governments take greater responsibility for the wellness of the poorest residents. Governments are often a large part of the problem, however. Most of the poorest settlements are on land that is illegally occupied or subdivided, so urban bureaucracies may ignore their existence. In addition, formal laws and institutions tend to assume that people can afford to live in sanitary homes and therefore often do more to marginalize communities that are at the edge of subsistence than to help them. Governments may also shy away from engaging with activists who encourage impoverished residents to organize around demands for improvements, but these organizers must be engaged if government programs that are put in place can hope to succeed.

Bright spots exist, however. Some local governments are now acknowledging the informal settlements and are collaborating with the inhabitants to install the health infrastructure and services needed. One of the most effective initiatives is the secure housing program run by the government of Thailand’s Community Organizations Development Institute, which has supported hundreds of community-driven upgrading schemes, including paying for better water and sewage infrastructure and lending money to shack dwellers to improve their homes. Federations of slum dwellers are working with local authorities to change conditions in more than 15 other nations. As these programs show, poor people’s health and their economic status both benefit most when governments, international agencies and slum dwellers work together to plan, implement and manage changes. More cities must see their “uncounted, unhealthy masses” as partners with resources and capacities if they want to complete a meaningful urban revolution.

Source of Information : Scientific American Magazine

Password Prevented

In a world drowning in absurd security requirements, it’s nice to see a few islands of reason

Nobody seems to think_ much about passwords. After all, isn’t their purpose obvious? You need one on your bank account so that nobody else can use your money. You need one on your e-mail account so that strangers can’t find out your innermost thoughts. But I was astonished when my daughter told me that her school has instituted a new security initiative. Student passwords must now be at least eight characters long, must contain letters, numbers and punctuation, and may not incorporate any recognizable English word. And the password must be changed every 30 days.

Can you guess what this password is meant to lock down? The fifth-grade homework downloading Web page. That’s right. All of that inconvenience, memorization
And hassle is intended to make sure some disturbed maniac doesn’t read this week’s spelling list. Then there’s the video production company I worked with recently, which hired a new tech guy. The first thing he did was to declare the company’s network to be unsafe. He decided that workers could no longer choose their own passwords; he would supply them. They would be 12 characters long and consist of alphanumeric gibberish, and they would have to be changed every month.

He also blocked chat programs, e-mail attachments and YouTube. So is the production company more secure? That’s hard to say. They haven’t had any hacker break-ins—of course, they had never had any before, either. But there is a difference. Now the employees watch YouTube videos on their phones, use Gmail to get file attachments and keep their unmemorizable passwords on Post-It notes taped to the monitor. Nice going, Mr. Security.

My point, of course, is that while it’s important to be secure, it’s equally important to ask why—and to consider the trade-off between security and convenience. Obscure and harmless entities sometimes get locked up like Fort Knox, punishing nobody but the legitimate users. (Don’t even get me started on the Transportation Security Administration.) Other entities, such as Sony, Citibank and Lockheed Martin, are apparently not locked up enough. (Their computer systems were all hacked this past spring.)

It is actually possible to devise a system that ensures both security and convenience—if you’re smart. For example, if you reserve a room as a member of Omni Hotels’s Select Guest loyalty program, you can check in just by walking up to the counter and giving your name. They hand over your key and say, “Good evening, [your name here]. Have a great stay.”

They don’t ask for your ID. They don’t say, “May I have your credit card for incidentals?” They don’t tap on their keyboard for five minutes. They don’t ask you any questions. No interrogation of any kind. They have your key waiting, and they just hand it over. How can they get away with such lax security? Couldn’t some ruffian pose as you, take your key and crawl into the bed in your hotel room? It’s never happened in the history of the Omni’s Express check-in program. Why not? Because theru ruffians don’t know who you are or that you’ve booked a hotel room. And if you ever did arrive and find some evildoer in your bed, you would be able to clear up the confusion pretty quickly by showing your ID.

Here’s another example: When you buy a program from Apple’s online Mac App Store, the program is downloaded and installed on your Mac automatically. You are not prompted for your system password, you don’t click through any installer screens, there’s no warning about software downloaded from the Internet. It’s the height of convenience.

Shouldn’t Apple be more worried about security? No, because it’s done some thinking. It controls both ends of the transaction. It’s not worried about viruses or malware, because it’s providing the software itself. It doesn’t have to ask you if you want to install the software—of course you want to (otherwise, why would you be buying it?). Whether you’re an administrator, designer or consumer, in other words, it’s worth putting some thought into the security/convenience trade-off. Passwords have their place—but it’s not every place.

Source of Information : Scientific American Magazine

Cooking That Sucks

Vacuum pumps in the kitchen

Nature, famously, abhors a vacuum. But some cooks have learned to feel differently. Step through the swinging doors at the back of a top restaurant like Alinea in Chicago, and you may find vacuum pumps being used to reduce cooking juices into concentrated sauces, to distill essential oils from fruits and vegetables, to dehydrate chips or to brew coffee.

Many of these techniques originated in chemistry laboratories or industrial food-processing operations, and the equipment involved still evokes the bench scientist more than the top chef. But with all those Erlenmeyer flasks, innovative cooks have discovered ways to achieve culinary feats that are impractical by any conventional means.

Consider the common problem of concentrating the flavors and aromas that are in a dilute liquid mixture, such as a broth. The old-fashioned method—a long stovetop simmer to boil off the water—allows many of the most piquant and fragrant compounds to escape with the steam. The kitchen may smell great—but at the cost of a duller sauce. A lengthy sit over the heat also chemically alters many of those compounds that remain, so they no longer taste or smell fresh. A vacuum-reduction setup does a better job because it uses low pressure, rather than high heat, to accelerate evaporation. Pour the liquid into a Pyrex flask that has a side port and connect the flask to a vacuum pump with a rubber hose. Then drop in a magnetic rod, stopper the flask and put it on a hot plate, which uses a spinning magnet to stir and gently warm the broth while the pump reduces the air pressure inside the flask. As the pressure drops, the boiling point of the liquid falls as well; the goal is to sustain a mild, low-temperature boil.

That relatively simple setup greatly reduces chemical changes, but it still permits some aromatics to escape through the hose. A more expensive and complex bit of gear, called a rotary evaporator, can capture those vaporized essences and condense them back into liquid form. The cooks at our research kitchen in Bellevue, Wash., use this technique to concentrate apple juice, cabbage juice and vinegar to make a fantastic red coleslaw. Concentrated watermelon juice is also a delight.

Source of Information : Scientific American Magazine 2011

New Help for Smokers

An antinicotine vaccine is moving closer to regulatory approval

As any smoker can tell you, quitting is relatively easy. The hard part is avoiding relapse—the urge to light up weeks or even months after you have supposedly kicked the habit. The patch, the gum and all the other tricks smokers use to get through the first few months are often powerless against those later urges.

That is one reason why an antinicotine vaccine now wending its way through clinical trials has public health officials so excited. Like all vaccines, NicVAX, made by NABI Biopharmaceuticals works by stimulating the body’s immune system to produce antibodies against a certain target—in this case, nicotine. Because immune responses are generally lifelong, the vaccine makers say it could serve as a longterm antismoking aid.

Normally nicotine molecules are small enough to evade detection by the immune system.
They are even small enough to slip past the blood-brain barrier and bind to receptors on brain cells, where they trigger a chemical cascade that leads to addiction. NicVAX floods the body with nicotine molecules that have been chemically attached to large, carrier proteins, forcing the immune system to recognize and deploy antibodies against the cigarette ingredient. Then, when ordinary nicotine molecules enter the system, those antibodies bind to them, making them too large to cross the blood-brain barrier.

The vaccine doesn’t work for everyone. An earlier trial showed that 16 percent of heavy smokers who were vaccinated and had high antibody levels remained abstinent from cigarettes one year after quitting, compared with 6 percent of the placebo group. Those who produced high antibodies but did not quit cut their smoking in half, from around 20 cigarettes a day to 10.

Results from wider, or “phase III,” trials are expected as early as September. For these studies, researchers recruited 1,000 smokers who consume at least 10 cigarettes a day. The volunteers received five to six injections spaced roughly one month apart and were asked to quit after 14 weeks, when around 80 percent of subjects have high antibody levels. (Why 20 percent of subjects fail to produce a high antibody response to the vaccine is unclear.). “The idea is to ensure that when we tell them to quit, they have the tools—the antibodies— to help them,” says NABI CEO Raafat E. F. Fahim. He and his team have yet to determine how long patients will need to get shots.

If results from the phase III trials are as good as everyone expects, the vaccine could hit pharmacy shelves soon after. Meanwhile researchers are already at work on other antiaddiction vaccines, including one against cocaine that employs the same strategy as NicVAX.

Source of Information : Scientific American Magazine