Sunday, August 1, 2010

NEW HYPOTHESIS FOR HUMAN EVOLUTION AND HUMAN NATURE

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It's no secret to any dog-lover or cat-lover that humans have a special connection with animals. But in a new journal article and forthcoming book, paleoanthropologist Pat Shipman of Penn State University argues that this human-animal connection goes well beyond simple affection. Shipman proposes that the interdependency of ancestral humans with other animal species — "the animal connection" — played a crucial and beneficial role in human evolution over the last 2.6 million years.

"Establishing an intimate connection to other animals is unique and universal to our species," said Shipman, a professor of biological anthropology. Her paper describing the new hypothesis for human evolution based on the tendency to nurture members of other species will be published in the August 2010 issue of the journal Current Anthropology.

In addition to describing her theory in the scientific paper, Shipman has authored a book for the general public, now in press with W. W. Norton, titled The Animal Connection. "No other mammal routinely adopts other species in the wild — no gazelles take in baby cheetahs, no mountain lions raise baby deer," Shipman said. "Every mouthful you feed to another species is one that your own children do not eat. On the face of it, caring for another species is maladaptive, so why do we humans do this?"

Shipman suggests that the animal connection was prompted by the invention of stone tools 2.6-million years ago. "Having sharp tools transformed wimpy human ancestors into effective predators who left many cut marks on the fossilized bones of their prey," Shipman said. Becoming a predator also put our ancestors into direct competition with other carnivores for carcasses and prey. As Shipman explains, the human ancestors who learned to observe and understand the behavior of potential prey obtained more meat. "Those who also focused on the behavior of potential competitors reaped a double evolutionary advantage for natural selection," she said.

Over time, Shipman explains, the volume of information about animals increased, the evolutionary benefits of communicating this knowledge to others increased, and language evolved as an external means of handling and communicating information through symbols. "Though we cannot discover the earliest use of language itself, we can learn something from the earliest prehistoric art with unambiguous content. Nearly all of these artworks depict animals. Other potentially vital topics — edible plants, water, tools or weapons, or relationships among humans — are rarely if ever shown," Shipman said. She sees this disproportion as evidence that the evolutionary pressure to develop an external means of storing and transmitting information — symbolic language — came primarily from the animal connection

Shipman concludes that detailed information about animals became so advantageous that our ancestors began to nurture wild animals — a practice that led to the domestication of the dog about 32,000 years ago. She argues that, if insuring a steady supply of meat was the point of domesticating animals, as traditionally has been assumed, then dogs would be a very poor choice as an early domesticated species. "Why would you take a ferocious animal like a wolf, bring it into your family and home, and think this was advantageous?" Shipman asks. "Wolves eat so much meat themselves that raising them for food would be a losing proposition."

Shipman suggests, instead, that the primary impetus for domestication was to transform animals we had been observing intently for millennia into living tools during their peak years, then only later using their meat as food. "As living tools, different domestic animals offer immense renewable resources for tasks such as tracking game, destroying rodents, protecting kin and goods, providing wool for warmth, moving humans and goods over long distances, and providing milk to human infants" she said.

Domestication, she explained, is a process that takes generations and puts selective pressure on abilities to observe, empathize, and communicate across species barriers. Once accomplished, the domestication of animals offers numerous advantages to those with these attributes. "The animal connection is an ancient and fundamentally human characteristic that has brought our lineage huge benefits over time," Shipman said. "Our connection with animals has been intimately involved with the evolution of two key human attributes — tool making and language — and with constructing the powerful ecological niche now held by modern humans."

(Photo: H. Jensen. Copyright: University of Tübingen)

Penn State University

RESEARCHERS SEEKING THE FOURTH PROPERTY OF ELECTRONS

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Electrons are negatively charged elementary particles. They form the shells around atoms and ions. This or something similar is what you will find in text books. Soon, however, this information may have to be supplemented. The reason is that many physicists believe that electrons have a permanent electric dipole moment.

An electric dipole moment is usually created when positive and negative charges are spatially separated. Similar to the north and south poles of a magnet, there are two electric poles. In the case of electrons, the situation is much more complicated because electrons should not actually have any spatial dimension. Despite this, an entire range of physical theories that go beyond the standard model of elementary particle physics are based upon the existence of dipole moment. These theories in turn would explain how the universe in the form that we know it could have been created in the first place. According to prevailing theories, the big bang some 13.7 billion years ago would have had to have created just as much matter as antimatter. Since both obliterate each other, nothing would have remained. In reality, however, more matter than antimatter was actually created. An electric dipole moment of the electron could explain this imbalance.

Up to now, nobody has successfully proven the existence of this assumed tiny dipole moment. Existing methods are simply not sensitive enough. A small piece of ceramic is set to change this soon. Dr. Marjana Ležaić and Dr. Konstantin Rushchanskii from the Institute of Solid State Physics at Forschungszentrum Jülich and Professor Nicola Spaldin from the University of California in Santa Barbara designed this ceramic, which has very special properties, in a virtual laboratory using the Jülich supercomputer JUROPA. The new europium barium titanate should enable measurements to be 10 times more sensitive than they were in the past. According to the Jülich physicists, "this could be sufficient to find the electric dipole moment of the electron".

As electric moment cannot be directly measured, the physicists are working together with scientists from the American Yale University as well as with Czech research institutions in Prague in order to indirectly prove its existence. The researchers in Yale have developed an experimental setup that uses an extremely sensitive SQUID magnetometer to measure the magnetization of the piece of ceramic in an electric field. Their aim is to demonstrate a change in the magnetization when the electric field is reversed. This would simultaneously be the sought-after evidence that the electric dipole moment exists. In an electron, an electric dipole can only ever be oriented parallel or anti-parallel to the electron spin. In an electric field, most of the electrons are oriented so that their dipole moment is parallel to the field. Fewer are oriented in the other direction. This should lead to a measurable magnetization. If the electric field is reversed, the dipole moments of the electrons are reversed leading consequently to a simultaneous, measurable change in the magnetization. Without an electric dipole moment, on the other hand, the magnetization would remain unchanged.

"It would have been very difficult to find such a well-suited material by trial and error," said Ležaić. This material must have an unusual combination of properties: a high concentration of magnetic ions, magnetic disorder at temperatures below four degrees Kelvin and a reversible electric polarization. "Our colleagues in Yale who came up with the idea of the measurements and conducted them had already tested different materials. However, a new material with all of the necessary properties can be found faster with the use of theoretical analysis and computer simulations." Ležaić, as the head of the young investigators group, her group member Rushchanskii, and her cooperation partner Spaldin virtually synthesized and analysed europium barium titanate on the supercomputer in Jülich. To do so, all they needed was its chemical composition and the basic equations of quantum mechanics. From these, they calculated the interaction between individual atoms and electrons and the local magnetic properties. So it was that they found the optimum ceramic.

Team colleagues in Prague have already synthesized and characterized the material in the laboratory and confirmed the properties calculated in Jülich. Only the sought-after dipole moment of the electron remains undiscovered. "Unwanted effects are still inhibiting the measurements," said a disappointed Ležaić. "But we're working intensively on improving the material even further."

(Photo: Forschungszentrum Juelich)

The Helmholtz Association

FOREIGN ACCENTS MAKE SPEAKERS SEEM LESS TRUTHFUL TO LISTENERS

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A foreign accent undermines a person's credibility in ways that the speaker and the listener don't consciously realize, new research at the University of Chicago shows.

Because an accent makes a person harder to understand, listeners are less likely to find what the person says as truthful, researchers found. The problem of credibility increases with the severity of the accent.

"The results have important implications for how people perceive non-native speakers of a language, particularly as mobility increases in the modern world, leading millions of people to be non-native speakers of the language they use daily," said Boaz Keysar, a Professor of Psychology at the University of Chicago and an expert on communication.

"Accent might reduce the credibility of non-native job seekers, eyewitnesses, reporters or people taking calls in foreign call centers," said Shiri Lev-Ari, lead author of "Why Don't We Believe Non-native Speakers? The Influence of Accent on Credibility," written with Keysar and published in the current issue of the Journal of Experimental Social Psychology. Levi-Ari is a post-doctoral researcher at the University whose work focuses on the interactions between native and non-native speakers.

To test the impact of accent on credibility, American participants were asked to judge the truthfulness of trivia statements by native or non-native speakers of English, such as, "A giraffe can go without water longer than a camel can."

Simple prejudice could affect ratings of truthfulness, so the researchers tried to minimize that effect by telling participants the information in the statements was prepared for the speakers, and was not based on the speakers' own knowledge.

Despite knowing the speakers were reciting from a script, the participants judged as less truthful the statements coming from people with foreign accents. On a truthfulness scale prepared for the experiment, the participants gave native speakers a score of 7.5, people with mild accents a score of 6.95 and people with heavy accents a score of 6.84.

"The accent makes it harder for people to understand what the non-native speaker is saying," Keysar said. "They misattribute the difficulty of understanding the speech to the truthfulness of the statements."

In a second experiment, researchers tested whether awareness reduces the impact of accent on perceived truthfulness. Researchers told participants that they were being tested to see if accents undermine credibility.

That experiment was conducted with identical recorded statements, but with different results. While participants rated statements with mild accent just as truthful as statements by native speakers, they rated heavily accented statements as less truthful, Lev-Ari said.

Accent is one of the factors that influences people's perception of foreigners in a society, Keysar pointed out. But its insidious impact on credibility is something researchers had not previously known, he added.

University of Chicago

BATTERY RESEARCH COULD LEAD TO SHORTER RECHARGE TIME FOR CELL PHONES

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New battery materials developed by the Department of Energy's Pacific Northwest National Laboratory and Vorbeck Materials Corp. of Jessup, Md., could enable electric vehicles, power tools and even cell phones to recharge in minutes rather than hours.

In collaboration with Vorbeck and researcher Ilhan Aksay at Princeton University, PNNL has demonstrated that small quantities of graphene — an ultra-thin sheet of carbon atoms — can dramatically improve the power and cycling stability of lithium-ion batteries, while maintaining high energy storage capacity. The pioneering work could lead to the development of batteries that store larger amounts of energy and recharge quickly.

Today, a typical cell phone battery takes between two and five hours to fully recharge. Researchers think using new battery materials with graphene could cut recharge time to less than 10 minutes.

Battelle, which operates PNNL for DOE, entered into a Cooperative Research and Development Agreement with Vorbeck for use of its unique graphene material, Vor-xTM, in battery materials synthesis research.

This research is made possible the by the Department of Energy's Office of Energy Efficiency and Renewable Energy's Technology Commercialization Fund.

(Photo: PNNL)

Pacific Northwest National Laboratory

A PERSON'S LANGUAGE MAY INFLUENCE HOW HE THINKS ABOUT OTHER PEOPLE

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The language a person speaks may influence their thoughts, according to a new study on Israeli Arabs who speak both Arabic and Hebrew fluently. The study found that Israeli Arabs' positive associations with their own people are weaker when they are tested in Hebrew than when they are tested in Arabic.

The vast majority of Arab Israelis speak Arabic at home and usually start learning Hebrew in elementary school. The subjects in this study were Arab Israelis, fluent in both Hebrew and Arabic, who were students at Hebrew-speaking universities and colleges. Researchers Shai Danziger of Ben-Gurion University and Robert Ward of Bangor University took advantage of the tensions between Arabs and Israelis to design an experiment that looked at how the students think differently in Arabic and Hebrew. Their hypothesis: "It's likely that a bilingual Arab Israeli will consider Arabs more positively in an Arab speaking environment than a Hebrew speaking environment," says Danziger.

The study used a computer test known as the Implicit Association Test, which is often used to study bias. Words flash on the computer screen, and subjects have to categorize them by pressing two keys on the keyboard as quickly as possible. It's a nearly automatic task, with no time to think about the answers. The trick is, the subjects are classifying two different kinds of words: words describing positive and negative traits and, in this case, names - Arab names like Ahmed and Samir and Jewish names like Avi and Ronen. For example, they might be told to press "M" when they saw an Arab name or a word with a good meaning, or "X" when they saw a Jewish name and a word with a bad meaning. In this example, if people automatically associate "good" words with Arabs and "bad" with Jews, they'll be able to do the classifications faster than if their automatic association between the words is the other way around. In different sections of the test, different sets of words are paired.

For this study, the bilingual Arab Israelis took the implicit association test in both languages “Hebrew and Arabic” to see if the language they were using affected their biases about the names. The Arab Israeli volunteers found it easier to associate Arab names with "good" trait words and Jewish names with "bad" trait words than Arab names with "bad" trait words and Jewish names with "good" trait words. But this effect was much stronger when the test was given in Arabic; in the Hebrew session, they showed less of a positive bias toward Arab names over Jewish names. "The language we speak can change the way we think about other people," says Ward. The results are published in Psychological Science, a journal of the Association for Psychological Science.

Danziger himself learned both Hebrew and English as a child. "I am a bilingual and I believe that I actually respond differently in Hebrew than I do in English. I think in English I'm more polite than I am in Hebrew," he says. "People can exhibit different types of selves in different environments. This suggests that language can serve as a cue to bring forward different selves."

The Association for Psychological Science

ETHANOL-FUELED RACECAR ENGINES OUTPOWER LEAD-FUELED ENGINES

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A group of automotive researchers from the U.S. Department of Energy's (DOE) Argonne National Laboratory and industry have shown that a fuel-injected racing car engine fueled by E-85, an ethanol-based fuel, outperforms the same engine with a carburetor and leaded racing fuel.

Specifically, the group, dubbed Project Green, demonstrated during benchmark testing a seven percent improvement in the torque and speed of a General Motors' CT525 LS3 fuel-injected engine with a catalytic convertor attached to the exhaust system and renewable E-85 in the fuel tank, said Forrest Jehlik, principal mechanical engineer at Argonne's Center for Transportation Technology. The General Motors engine is a popular choice among circle track racers.

"The testing disproves two widely and firmly held beliefs in the circle track racing community – that carbureted engines are inherently more powerful than engines equipped with a fuel injection system; and that E-85, which is less expensive than leaded racing fuel, is not well-suited as a fuel for race cars," said Jehlik, who leads the benchmark testing for Project Green.

Aside from the garages of classic and vintage car collectors, race tracks are about the only venues these days where engines with carburetors are in active use. Fuel injection systems began replacing carburetors in earnest in the early 1980s because they allow for greater fuel efficiency as a result of precise and even fuel distribution to each cylinder.

Moreover, tailpipe emissions from cars with fuel injection engines are lowered due to the precise metering of fuel, thereby reducing the amount of oxides of nitrogen, hydrocarbon and carbon monoxide combustion byproducts.

Catalytic convertors, which further reduce the amount of emissions generated by internal combustion engines, are not normally part of the exhaust systems of racing cars. But Project Green's dynamometer testing of the GM engine utilizing catalytic convertors resulted in a 50 percent to 60 percent decrease in nitrogen oxide, one of the main ingredients involved in the formation of ground-level ozone.

However, there was not an appreciable decrease in carbon monoxide and hydrocarbon emissions. After analyzing the test data to determine why the decrease was so slight, the team developed a secondary air-injection system that will increase the level of oxygen in the exhaust stream and thereby allow oxidation of those by-products. Results from on-track testing set for the week of July 12th at the New Smyrna Speedway in New Smyrna Beach, Fla., are expected to validate that new approach.

Professional circle track racing series have been reluctant to require racing teams to use today's cleaner and more efficient automotive technologies and fuels in their vehicles. But Project Green is optimistic that these technologies will eventually be adopted by the sport, just as the American Le Mans Series' Green Challenge has adopted green racing principles established by DOE, the U.S. Environmental Protection Agency and the Society of Automotive Engineers.

"If you start getting the racing community to see that cars can run just as fast and more efficiently with fuel-injected engines and domestically produced biofuels that are more environmentally friendly and less expensive, it has the potential to really catch on with race car drivers and their large fan base," Jehlik said.

"The bottom line is that we have shown that modern fuel-injection technology, renewable E-85 fuel and catalytic convertors provide better performance and increased efficiency while reducing emissions; it is a reality today. Truly, there are no compromises. It’s a win-win for everyone, and we believe it is the future of racing and a step towards sustainability in the transportation fuels we use as a country."

(Photo: Darryl Moran / Creative Commons)

Argonne National Laboratory

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