Monday, July 26, 2010

ARCHAEOLOGY FIND SHEDS NEW LIGHT ON FAMILY PETS

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A University of Leicester archaeologist has discovered a bone belonging to a late 19th-century tortoise from Stafford Castle, Staffordshire - believed to be the earliest archaeological evidence of a tortoise kept as a family pet.

As reported in Post-Medieval Archaeology (volume 44/1) by University of Leicester archaeologist Dr Richard Thomas, the significance of the find is in the insights it gives on the early importation of tortoises and the changing attitude of British society towards family pets.

The Stafford Castle tortoise bone was found amongst the skeletons of cats and dogs, in a context that suggests it was kept as a pet, possibly by the family who were caretakers at the castle at the time. The date of the find coincides with the late 19th-century increase in the trade of live animals and with the widespread importation of tortoises in particular.

As Dr. Thomas says, “Although we have archaeological evidence for terrapins and turtles from the 17th century, this is the first archaeological evidence we have for land tortoise in Britain. It seems very likely that this specimen was imported from North Africa or the Mediterranean; by the later 19th-century there was a dramatic rise in the commercial trade in tortoises from these regions to satisfy the growing demand for pet animals”.

The morality of keeping pets was considered highly suspect in the strict religious doctrines of Medieval and Early Modern society, and although there was an avid fascination in exotic creatures at the time, this seems to have curiously bypassed the tortoise.

Attitudes towards pets began to change in the 17th century, particularly under the famously dog-loving Stuart kings, and the reputation of the tortoise had certainly risen high enough by the early 17th century for the ill-fated Archbishop Laud to have kept one.

During the 18th and 19th centuries a more ‘modern’ attitude to pet animals gradually emerged. The sculptor Joseph Gott created sentimental statues of dogs during the 19th century, and in 1824 the Society (later Royal Society) for the Prevention of Cruelty to Animals was founded.

Pet burials have also been found from the period, in stark contrast to the bones of earlier domestic animals simply thrown out with the rubbish.

The discovery of the Stafford Castle tortoise bone a few years ago, now reported in Post-Medieval Archaeology, adds to the archaeological evidence that by the late 19th century ordinary families were keeping animals as pets with which there was probably some bond of affection.

As Dr. Thomas reveals, “Unfortunately, this interest in keeping exotic pet animals resulted in the capture and translocation of millions of wild tortoises each year during the 20th century. The animals were crated in ships and kept in appalling conditions; countless tortoises died during this journey and those that survived fared little better, given away as fairground prizes and kept by people with little knowledge of their upkeep. It was not until an EEC regulation in 1988, that this trade in wild tortoises was prohibited”.

Dr Richard Thomas is a Zooarchaeologist and Head of the University of Leicester’s Bone Laboratory in the internationally acclaimed School of Archaeology and Ancient History. His research interests focus on the study of animal bones as a means of understanding past human-animal relationships.

(Photo: U. Leicester)

University of Leicester

YOU CAN'T HIDE YOUR LYIN' EYES

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Shifty eyes long have been thought to signify a person's problem telling the truth. Now a group of University of Utah researchers are taking that old adage to a new level.

Educational psychologists John Kircher, Doug Hacker, Anne Cook, Dan Woltz and David Raskin are using eye-tracking technology to pioneer a promising alternative to the polygraph for lie detection. The researchers' efforts to commercialize their new technology reached a milestone recently when the University of Utah licensed the technology to Credibility Assessment Technologies (CAT).

CAT is based in Park City, Utah, and managed by venture capitalists Donald Sanborn and Gerald Sanders, who are the president and chairman, respectively.

"The eye-tracking method for detecting lies has great potential," Sanders says. "It's a matter of national security that our government agencies have the best and most advanced methods for detecting truth from fiction, and we believe we are addressing that need by licensing the extraordinary research done at the University of Utah."

In addition to bringing the technology closer to the marketplace, the licensing also helps maintain the university's leadership in lie-detection research. The university has been a leader in the field for at least 30 years, through the work of Raskin and Kircher, who both completed substantial research on the subject. Raskin now is a professor emeritus.

Tracking eye movement to detect lies became possible in recent years because of substantial improvements in technology. The Utah researchers say they are the first to develop and assess the software and methods for applying these tests effectively.

Using eye movement to detect lies contrasts with polygraph testing. Instead of measuring a person's emotional reaction to lying, eye-tracking technology measures the person's cognitive reaction. To do so, the researchers record a number of measurements while a subject is answering a series of true-and-false questions on a computer. The measurements include pupil dilation, response time, reading and rereading time, and errors.

The researchers determined that lying requires more work than telling the truth, so they look for indications that the subject is working hard. For example, a person who is being dishonest may have dilated pupils and take longer to read and answer the questions. These reactions are often minute and require sophisticated measurement and statistical modeling to determine their significance.

"We have gotten great results from our experiments," says Kircher. "They are as good as or better than the polygraph, and we are still in the early stages of this innovative new method to determine if someone is trying to deceive you."

Besides measuring a different type of response, eye-tracking methods for detecting lies has several other benefits over the polygraph. Eye tracking promises to cost substantially less, require one-fifth of the time currently needed for examinations, require no attachment to the subject being tested, be available in any language and be administered by technicians rather than qualified polygraph examiners.

Research into this method began five years ago, when faculty members started discussing the concept casually. They secured seed funding and the university's Department of Educational Psychology hired new faculty with relevant skills. Each member of the research team fills an important function, but few ever dreamed they would be working on lie-detection technology.

"I came to the University of Utah to do work in reading comprehension, but I jumped at the chance to get involved with this research," Cook says. "That's the fun of this kind of job. You get the opportunity to collaborate with your colleagues to achieve more than any of you could individually."

People across campus assisted the researchers. Help included research assistance from graduate students, intellectual property management through the Technology Commercialization Office and business development advice through the David Eccles School of Business's Lassonde New Venture Development Center, which links faculty researchers with master's of business administration students and graduate students from science, engineering and law.

The researchers still have more development work to do, but they hope the recent licensing will help them attract the additional funding necessary and interest from potential customers. Numerous government agencies, such as the U.S. Department of Defense, Department of Homeland Security, Customs and Border Protection, and Department of Energy use polygraphs regularly to screen employees and applicants for sensitive positions, and these agencies always are looking for more effective ways to detect lies.

"It's exciting," Cook says, "that our testing method is going to be taken from a basic research program to commercial use."

University of Utah

EXERCISE'S BRAIN BENEFITS

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Athletes have long known about the natural “high” exercise can induce. Now, for the first time, medical researchers have demonstrated that exercise can reverse the effects in the brain of psychological trauma experienced early in life.

Exercise can ameliorate anxiety and depression-like behaviours induced by an adverse early-life environment by altering the chemical composition in the hippocampus – the part of the brain that regulates stress response, researchers from UNSW have found.

The findings, derived from studies on lab rats, are further evidence of the plasticity of the brain and its ability to re-map neural networks. Previous studies from UNSW’s School of Medical Sciences have shown that comfort eating – eating palatable food rich in fat and sugar – achieves similar results.

With many neurological diseases displaying origins in early life, the researchers believe the results could provide clues for novel ways to tackle a range of mood and behaviour disorders.

“What’s exciting about this is that we are able to reverse a behavioural deficit that was caused by a traumatic event early in life, simply through exercise,” said Professor of Pharmacology Margaret Morris, who will present the findings this week at the International Congress of Obesity in Stockholm.

In the study, rats were divided into groups and either isolated from their mothers for controlled periods of time to induce stress or given normal maternal contact. Half were given access to a running wheel.

In addition to being more anxious, animals that were subjected to stress early in life had higher levels of stress hormones and fewer steroid receptors in the part of the brain controlling behaviour.

“Both the anxious behaviour and the levels of hormones in these rats were reversed with access to the exercise wheel,” Professor Morris said.

“We know that exercise can elevate mood, but here we are seeing chemical changes that may underpin this improvement. One of these is increases in brain-derived neurotrophic factor (BDNF), which helps nerve cells grow.

“Many neurological diseases appear to have their origins early in life. Stress hormones affect the way nerve cells grow in the brain. This discovery may be giving us a clue about a different way to tackle a range of conditions that affect mood and behaviour,” she said.

“Here we also compared effects of exercise to eating palatable food, and it was equally effective, suggesting there’s a more healthy option as an alternative.”

A paper detailing the work appears this month in the journal Psychoneuroendocrinology.

The University of New South Wales

MOJOCERATOPS: NEW DINOSAUR SPECIES NAMED FOR FLAMBOYANT FRILL

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When Nicholas Longrich discovered a new dinosaur species with a heart-shaped frill on its head, he wanted to come up with a name just as flamboyant as the dinosaur's appearance. Over a few beers with fellow paleontologists one night, he blurted out the first thing that came to mind: Mojoceratops.

"It was just a joke, but then everyone stopped and looked at each other and said, ‘Wait — that actually sounds cool,' " said Longrich, a postdoctoral associate at Yale University.”I tried to come up with serious names after that, but Mojoceratops just sort of stuck."

With the publication of Longrich's paper describing his find in the Journal of Paleontology, the name is now official.

The dinosaur is one of more than a dozen species belonging to the chasmosaurine ceratopsid family, which are defined by elaborate frills on their skulls. A plant eater about the size of a hippopotamus, Mojoceratops appeared about 75 million years ago during the Late Cretaceous — 10 million years earlier than its well-known cousin, the Triceratops. The species, which is related to another dinosaur in Texas, is found only in Canada's Alberta and Saskatchewan provinces and was short-lived, having survived for only about one million years.

It was only after coming up with the unusual name that Longrich looked into its etymology. Surprisingly, he found that it was a perfect fit for the species, which sported a flamboyant, heart-shaped frill on its head.

"I discovered that ‘mojo' is an early 20th-century African-American term meaning a magic charm or talisman, often used to attract members of the opposite sex," he said. "This dinosaur probably used its frill to attract mates, so the name made sense." The full name is Mojoceratops perifania, with "perifania" meaning pride in Greek. (The other part of the name mojoceratops follows the convention of other related species, with "ceras" being Greek for horn and "ops" being Greek for face.)

While all ceratopsids have frills on the tops of their skulls, "Mojoceratops is the most ostentatious," Longrich said, adding that their frill is also the most heart-shaped of all the related species.

Longrich got his first clue that he might have found a new species at the American Museum of Natural History in New York, where he was studying the dinosaur fossil collection in 2008. There, he found a distinctive frill that didn't match anything previously known. Later, while sketching the skull of another specimen on display, which was thought to be a species called Chasmosaurus, he noticed the skull was identical to the one on the specimen next to it.

"I realized the skull on the supposed Chasmosaurus must have been a reconstruction," he explained. When he studied the front of the skull, Longrich noticed some differences from the typical Chasmosaurus, including longer horns than usual. Trips to other museums in Western Canada turned up more examples that didn't fit with the rest of the known species. "The fossils didn't look like anything we'd seen before. They just looked wrong," he said.

Finding yet another previously unknown large dinosaur species that comes from Dinosaur Provincial Park in Alberta, Canada-which boasts the world's most diverse dinosaur fauna-was somewhat surprising, Longrich said, because the fossils have been studied for such a long time already. "So far, we really have no good explanation for why there are so many dinosaurs in the area and just how they managed to coexist," he said.

All in all, Longrich turned up eight partial skulls of the new species, which now boasts a name with just as much flair as its unusually shaped head.

"You're supposed to use Latin and Greek names, but this just seemed more fun," Longrich said. "You can do good science and still have some fun, too. So why not?"

(Photo: Nicholas Longrich)

Yale University

SMOKING MIND OVER SMOKING MATTER

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Nicotine patches and gum are common — and often ineffective — ways of fighting cigarette cravings, as most smokers have discovered. Now a new study from Tel Aviv University shows why they're ineffective, and may provide the basis for more successful psychologically-based smoking cessation programs.

In the new study published in the Journal of Abnormal Psychology, Dr. Reuven Dar of Tel Aviv University's Department of Psychology found that the intensity of cravings for cigarettes had more to do with the psychosocial element of smoking than with the physiological effects of nicotine as an addictive chemical.

"These findings might not be popular with advocates of the nicotine addiction theory, because they undermine the physiological role of nicotine and emphasize mind over matter when it comes to smoking," Dr. Dar says. He hopes this research will help clinicians and health authorities develop more successful smoking cessation programs than those utilizing expensive nicotine patches or gum.

Dr. Dar and his colleagues' conclusions are based on two landmark studies. In the most recent study, he and his colleagues monitored the smoking behavior and craving levels of in-flight attendants, both women and men, who worked at the Israeli airline El Al. Each participant was monitored during two flights — a long flight of 10 to 13 hours in duration, from Tel Aviv to New York, for example; and a two-hop shorter trip from Israel to Europe and back, each leg lasting three to five hours. Using a questionnaire, he sampled craving levels of the attendants throughout the duration of their flights.

Dr. Dar and his colleagues found that the duration of the flight had no significant impact on craving levels, which were similar for short and long flights. Moreover, craving levels at the end of each short flight were much higher those at the end of the long flight, demonstrating that cravings increased in anticipation of the flight landing, whatever the flight's total duration. He concluded that the craving effect is produced by psychological cues rather than by the physiological effects of nicotine deprivation.

In an earlier 2005 study, Dr. Dar examined smokers who were religious Jews, forbidden by their religion to smoke on the Sabbath. He asked them about their smoking cravings on three separate days: the Sabbath, a regular weekday, and a weekday on which they'd been asked to abstain. Participants were interviewed at the end of each day about their craving levels during that day.

What Dr. Dar found is that cravings were very low on the morning of the Sabbath, when the smoker knew he would not be able to smoke for at least 10 hours. Craving levels gradually increased at the end of the Sabbath, when participants anticipated the first post-Sabbath cigarette. Craving levels on the weekday on which these people smoked as much as they wanted were just as high as on the day they abstained, showing that craving has little to do with nicotine deprivation.

Dr. Dar's studies conclude that nicotine is not addictive as physiological addictions are usually defined. While nicotine does have a physiological role in increasing cognitive abilities such as attention and memory, it's not an addictive substance like heroin, which creates true systemic and biologically-based withdrawal symptoms in the body of the user, he says.

Dr. Dar believes that people who smoke do so for short-term benefits like oral gratification, sensory pleasure and social camaraderie. Once the habit is established, people continue to smoke in response to cues and in situations that become associated with smoking. Dr. Dar believes that understanding smoking as a habit, not an addiction, will facilitate treatment. Smoking cessation techniques should emphasize the psychological and behavioral aspects of the habit and not the biological aspects, he suggests.

(Photo: TAU)

Tel Aviv University

ANCIENT BIRDS FROM NORTH AMERICA COLONISED THE SOUTH

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Scientists studying ancient species migration believe northern birds had the ability to colonise continents that southern species lacked. The research, published in Ecography, reveals how the ancient ‘land bridge’ of Panama, which first connected North and South America, caused an uneven species migration, leading to a new understanding of species diversity today.

The continents of North and South America were historically isolated until they were abruptly joined three million years ago through the tectonic uplift of Central America and the formation of a land corridor in modern day Panama, creating a land bridge.

“This connection allowed an unprecedented degree of intercontinental exchange between species that had been isolated for millions of years,” said lead author Brian Tilston Smith from the University of Nevada. “However the relatively poor fossil record has prevented us from understanding how the land bridge shaped New World bird communities.”

Using molecular data and phylogenetic evidence from 11 orders, 34 families, and over 100 genera of bird species the team applied a ‘molecular clock’ to estimate the historical timing of the migration, giving a unique insight into how the ancient history of American bird migration led to present day species diversity across the equator

The results reveal that while ancient birds could fly most species did not cross the water between the two isolated continents, so were subject to the same constraints as their land based mammalian counterparts. The land bridge was therefore crucial in facilitating cross continental migration.

“This inter-continental migration was far from even. While within the tropics around the equator exchange was equal in both directions, between the temperate zones of North and South America it was not,” said Smith. “Avian lineages from the northern Nearctic regions have repeatedly invaded the tropics and radiated throughout South America. In contract species with South American tropical origins remain largely restricted to the confines of the tropical regions.”

Existing studies show that in mammals 50% of modern South American species have Northern origins whereas only 10% of species from the North originated in the South. The team found that this pattern is also reflected in birds. When considering the perching birds oscine and suboscine the team found that despite having northern ancestral origins, 55% of New World oscine species now breed in South America, many of them in tropical habitats. In contrast, only 2.4% of suboscines have secondarily adapted to North American temperate zone habitats.

“Our study suggests the formation of the panama land bridge was crucial for allowing cross continental bird migration,” concluded Smith. “We believe that the ability of species to colonise and radiate across this area represents an important and underappreciated factor to the distribution of species around the equator.”

Wiley

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