After imaging during the holidays, NASA's Mars rover Curiosity resumed driving Jan. 3 and pulled within arm's reach of a sinuous rock feature called "Snake River."
Snake River is a thin curving line of darker rock cutting through flatter rocks and jutting above sand. Curiosity's science team plans to get a closer look at it before proceeding to other nearby rocks.
"It's one piece of the puzzle," said the mission's project scientist, John Grotzinger of the California Institute of Technology in Pasadena. "It has a crosscutting relationship to the surrounding rock and appears to have formed after the deposition of the layer that it transects."
The drive during the mission's 147th Martian day, or sol, on the Red Planet took Curiosity about 10 feet (3 meters) northwestward and brought the mission's total driving distance to 2,303 feet (702 meters). The rover is within a shallow depression called "Yellowknife Bay," which is a flatter and lighter-toned type of terrain from what the mission crossed during its first four months inside Gale Crater.
During a holiday break for the rover team, Curiosity stayed at a location within Yellowknife Bay from which the rover took images of its surroundings. The team is evaluating possible first targets for use of Curiosity's hammering drill in coming weeks. The drill will collect powdered samples from the interior of rocks for analysis by instruments inside the rover.
"We had no surprises over the holidays," said the mission's project manager, Richard Cook of NASA's Jet Propulsion Laboratory, Pasadena. "Now, Curiosity is back on the move. The area the rover is in looks good for our first drilling target."
Read more at Science daily
Jan 5, 2013
Secret to Fish's Waterfall-Climbing Ability Found
A waterfall-climbing fish in Hawaii uses the same muscles to both rise and feed, researchers have discovered.
Scientists looked at the Nopoli rock-climbing goby (Sicyopterus stimpsoni), also known in Hawaiian as o'opu nopili. This plant-eating fish is found throughout Hawaii, and was once greatly relished as food, apparently being a favorite snack among priests.
Many gobies can inch their way up waterfalls with the aid of a sucker on their bellies formed from fused pelvic fins. The Nopoli rock-climbing goby, on the other hand, can climb waterfalls as tall as 330 feet (100 meters) with the aid of a second mouth sucker, which develops after their mouthparts move from a forward-facing position to under the body during a two-day-long metamorphosis into adulthood.
"For a human to go the equivalent distance based on body size, it'd be like doing a marathon, some 26 miles (42 kilometers) long, except climbing up a vertical cliff-face against rushing water," researcher Richard Blob, an evolutionary biomechanist at Clemson University in South Carolina, told LiveScience. Indeed, an old Hawaiian saying is that as the Nopili clings, so will luck.
The goby, which can grow up to 7 inches (18 centimeters) long as an adult, feeds by cyclically sticking the tip of its upper jaw against rock to scrape food off surfaces. This behavior is quite distinct from other Hawaiian gobies, which feed by sucking in food from the water. Given the apparent similarity of the climbing and feeding behaviors of the S. stimpsoni species, researchers thought one might have developed from the other.
"The fish gave us an opportunity to see how unusual behaviors evolved," Blob said.
To see if these behaviors really were as similar as they looked, the scientists captured Nopoli rock-climbing gobies from a stream on the island of Hawaii by net while snorkeling and kept them in aquaria. They next filmed the gobies' jaw-muscle movements as the fish climbed and ate, either scraping food off glass microscope slides or climbing up angled plastic boards. They found that overall movements were indeed similar during both activities.
It remains uncertain whether feeding movements were adapted for climbing, or vice versa.
Read more at Discovery News
Scientists looked at the Nopoli rock-climbing goby (Sicyopterus stimpsoni), also known in Hawaiian as o'opu nopili. This plant-eating fish is found throughout Hawaii, and was once greatly relished as food, apparently being a favorite snack among priests.
Many gobies can inch their way up waterfalls with the aid of a sucker on their bellies formed from fused pelvic fins. The Nopoli rock-climbing goby, on the other hand, can climb waterfalls as tall as 330 feet (100 meters) with the aid of a second mouth sucker, which develops after their mouthparts move from a forward-facing position to under the body during a two-day-long metamorphosis into adulthood.
"For a human to go the equivalent distance based on body size, it'd be like doing a marathon, some 26 miles (42 kilometers) long, except climbing up a vertical cliff-face against rushing water," researcher Richard Blob, an evolutionary biomechanist at Clemson University in South Carolina, told LiveScience. Indeed, an old Hawaiian saying is that as the Nopili clings, so will luck.
The goby, which can grow up to 7 inches (18 centimeters) long as an adult, feeds by cyclically sticking the tip of its upper jaw against rock to scrape food off surfaces. This behavior is quite distinct from other Hawaiian gobies, which feed by sucking in food from the water. Given the apparent similarity of the climbing and feeding behaviors of the S. stimpsoni species, researchers thought one might have developed from the other.
"The fish gave us an opportunity to see how unusual behaviors evolved," Blob said.
To see if these behaviors really were as similar as they looked, the scientists captured Nopoli rock-climbing gobies from a stream on the island of Hawaii by net while snorkeling and kept them in aquaria. They next filmed the gobies' jaw-muscle movements as the fish climbed and ate, either scraping food off glass microscope slides or climbing up angled plastic boards. They found that overall movements were indeed similar during both activities.
It remains uncertain whether feeding movements were adapted for climbing, or vice versa.
Read more at Discovery News
Jan 4, 2013
The Internet is Gassy
Information communications and technologies (ICT), such as the Internet, account for approximately as much carbon dioxide emissions as the aviation industry, or roughly two percent of the global total, according to research by the consulting group Gartner.
As telecommunications use around the world continues to expand rapidly, their share of emissions may grow. However, ICT also may make other industries more efficient and reduce overall greenhouse gas emissions, experts say.
Jonathan Koomey, a researcher at the Steyer-Taylor Center for Energy Policy and Finance at Stanford University, told Discovery News that electricity use by computers was relatively modest compared to the energy they help save.
“Total electricity use for data centers was about 1.3 percent of global electricity use and two percent of U.S. electricity use in 2010, but that should help us use the other 98 percent of the electricity more efficiently, so on net, data centers probably reduce emissions,” said Koomey. “Long-term trends for computers show a doubling of efficiency every 1.5 years, a trend that has continued since the beginning of the computer age... .We're also shifting more towards mobile devices, which are much more efficient than their wired counterparts.”
“Turn off your computer at night and on weekends when not in use, enable your power management software, and use the Internet to help you avoid unnecessary errands and travel,” he said. "That should yield reduced emissions compared to the case where you didn't have a computer at all."
Greenhouse gas emissions from energy use by the Internet and related technologies were quantified in the mathematical models recently published in Environmental Science and Technology.
The use of ICT services dominates the sector’s contribution to greenhouse gas emissions, compared to the emissions associated with building the infrastructure, Thas Nirmalathas, study co-author and engineering professor in the University of Melbourne, Australia’s Centre for Energy Efficient Telecommunication (CEET), told Discovery News. Developing a standardized system for monitoring efficiency could reduce those emissions.
Operators and equipment manufacturers could then be able to use that information to improve designs.
In developing economies, such as India or China, providing Internet and other services could signifigantly increase the greenhouse gases attributable to ICT.
“The spread of ICT in the developing world is sharply rising,” said Nirmalathas. “Therefore we need to recognize that the ICT use by developing countries will be a significant portion of the carbon footprint of the ICT industry."
Read more at Discovery News
As telecommunications use around the world continues to expand rapidly, their share of emissions may grow. However, ICT also may make other industries more efficient and reduce overall greenhouse gas emissions, experts say.
Jonathan Koomey, a researcher at the Steyer-Taylor Center for Energy Policy and Finance at Stanford University, told Discovery News that electricity use by computers was relatively modest compared to the energy they help save.
“Total electricity use for data centers was about 1.3 percent of global electricity use and two percent of U.S. electricity use in 2010, but that should help us use the other 98 percent of the electricity more efficiently, so on net, data centers probably reduce emissions,” said Koomey. “Long-term trends for computers show a doubling of efficiency every 1.5 years, a trend that has continued since the beginning of the computer age... .We're also shifting more towards mobile devices, which are much more efficient than their wired counterparts.”
“Turn off your computer at night and on weekends when not in use, enable your power management software, and use the Internet to help you avoid unnecessary errands and travel,” he said. "That should yield reduced emissions compared to the case where you didn't have a computer at all."
Greenhouse gas emissions from energy use by the Internet and related technologies were quantified in the mathematical models recently published in Environmental Science and Technology.
The use of ICT services dominates the sector’s contribution to greenhouse gas emissions, compared to the emissions associated with building the infrastructure, Thas Nirmalathas, study co-author and engineering professor in the University of Melbourne, Australia’s Centre for Energy Efficient Telecommunication (CEET), told Discovery News. Developing a standardized system for monitoring efficiency could reduce those emissions.
Operators and equipment manufacturers could then be able to use that information to improve designs.
In developing economies, such as India or China, providing Internet and other services could signifigantly increase the greenhouse gases attributable to ICT.
“The spread of ICT in the developing world is sharply rising,” said Nirmalathas. “Therefore we need to recognize that the ICT use by developing countries will be a significant portion of the carbon footprint of the ICT industry."
Read more at Discovery News
Banned 'Aristotle' Sex Manual Goes to Auction
A 18th century sex manual is going to be auctioned in Edinburgh nearly 200 years after it was banned from sale in Britain.
Known as Aristotle’s Complete Master-Piece, the book has little to do with Greek philosophy.
"It has very little at all to do with Aristotle. In fact, first published in 1684, the book is an early manual of sex and pregnancy," Cathy Marsden, a book specialist at the auction house Lyon and Turnbull in Edinburgh, where the copy is set to be auctioned, said in a statement.
Drawing from the works of Nicholas Culpepper, an English herbalist, physician, and astrologer, and Albertus Magnus, the German bishop and scientist, with a good dose of old wives' tale, the manual became hugely popular in Britain, and continued to be a best-seller on the black market after it was banned for being considered "highly distasteful and lewd."
"There were more editions of this work published in the 18th century than any other medical text," Marsden said.
The book, whose author is unknown, remained forbidden reading until the 1960s, when the ban was finally lifted.
By today’s standards, the manual is more amusing than graphic.
Emphasizing late 17th-century ideas surrounding female sexuality, the book described female and male anatomy, offering "advice to both sexes on the act of copulation."
Interestingly, the manual stressed that it was beneficial for a woman to experience sexual desire in order to conceive.
"Much later on, when they realized that a woman didn't have to climax in order to conceive, the idea of a woman enjoying sex was considered far less important," Marsden told reporters.
The manual is also peppered with urban myths, warning on the "risks of having sex outside marriage" and the impact that such an action "could have on the birth of the child."
Indeed, the book is illustrated with strange images of hairy children and other "monstrous births."
According to the manual, such deformities were "a curse laid upon the child for the incontinency of the parents."
Read more at Discovery News
Known as Aristotle’s Complete Master-Piece, the book has little to do with Greek philosophy.
"It has very little at all to do with Aristotle. In fact, first published in 1684, the book is an early manual of sex and pregnancy," Cathy Marsden, a book specialist at the auction house Lyon and Turnbull in Edinburgh, where the copy is set to be auctioned, said in a statement.
Drawing from the works of Nicholas Culpepper, an English herbalist, physician, and astrologer, and Albertus Magnus, the German bishop and scientist, with a good dose of old wives' tale, the manual became hugely popular in Britain, and continued to be a best-seller on the black market after it was banned for being considered "highly distasteful and lewd."
"There were more editions of this work published in the 18th century than any other medical text," Marsden said.
The book, whose author is unknown, remained forbidden reading until the 1960s, when the ban was finally lifted.
By today’s standards, the manual is more amusing than graphic.
Emphasizing late 17th-century ideas surrounding female sexuality, the book described female and male anatomy, offering "advice to both sexes on the act of copulation."
Interestingly, the manual stressed that it was beneficial for a woman to experience sexual desire in order to conceive.
"Much later on, when they realized that a woman didn't have to climax in order to conceive, the idea of a woman enjoying sex was considered far less important," Marsden told reporters.
The manual is also peppered with urban myths, warning on the "risks of having sex outside marriage" and the impact that such an action "could have on the birth of the child."
Indeed, the book is illustrated with strange images of hairy children and other "monstrous births."
According to the manual, such deformities were "a curse laid upon the child for the incontinency of the parents."
Read more at Discovery News
Dinosaurs Shook Their Tail Feathers
Some dinosaurs danced and literally shook their tail feathers to attract potential mates, researchers say.
It's long been theorized that at least some feathered dinosaurs used their plumage for courtship. A new study, published in the journal Acta Palaeontologica Polonica, strengthens that belief.
The dancing, prancing dinosaurs were oviraptors -- two legged, plant-eating dinos, related to T. rex, that roamed parts of China, Mongolia and Alberta during the Cretaceous period, which was the final age of the dinosaur.
"Oviraptors clearly had the anatomy needed to sinuously swish and to gracefully flaunt their tails," lead author Scott Persons told Discovery News, adding that many of these dinosaurs also had arm fans and head crests, which could have been part of such eye-catching moments.
"I suspect that a displaying oviraptor would be quite a sight, but the precise choreography of a dinosaur mating dance is the sort of thing that you can't learn from bones and is, sadly, the sort of thing that paleontologists will probably never know."
Persons, a researcher at the University of Alberta, and his team, however, were able to tell a lot about the dinosaurs’ appearance and behavior based on fossil evidence.
The scientists noticed that individual vertebrae at the base of an early oviraptor Similicaudiptery and related species were short and numerous, indicating great flexibility. Based on dissections of modern reptile and bird tales, a reconstruction of the dinosaur’s tail muscles revealed oviraptors had what it took to really shake their tail feathers.
Large muscles would have extended far down the tail, having a sufficient number of broad connection points to propel the dinosaur's tail feathers vigorously from side to side and up and down.
Modern-day peacocks and turkeys use their tail plumage in a similar way. It's possible that some oviraptor feathers were as beautiful and striking as those of peacocks.
"Exceptional fossils of oviraptors from China, which were preserved in fine volcanic ash, show definitively that at least some of the tail feathers had bands of contrasting color," Persons explained. "They may have had iridescent feathers, like a peacock, but that is a harder question, and one without definitive evidence."
As for today's birds that use tail plumage to attract mates, the researchers suspect males did most of the feather flaunting and displaying.
While the timeline for feather evolution is still somewhat of a mystery, the new findings provide intriguing clues.
Oviraptors with tail feather fans date back to over 120 million years, but Persons said that "they already have well developed feathers, so I doubt that they were the first."
He thinks dinosaur feathers initially evolved for insulation, with flight and courtship uses following later. It's even possible that insulating feathers first evolved in the reptilian ancestors of dinosaurs.
"The oldest fossil feathers are nearly 160 million years old, but feathers must have evolved many millions of years before that," he said.
Read more at Discovery News
It's long been theorized that at least some feathered dinosaurs used their plumage for courtship. A new study, published in the journal Acta Palaeontologica Polonica, strengthens that belief.
The dancing, prancing dinosaurs were oviraptors -- two legged, plant-eating dinos, related to T. rex, that roamed parts of China, Mongolia and Alberta during the Cretaceous period, which was the final age of the dinosaur.
"Oviraptors clearly had the anatomy needed to sinuously swish and to gracefully flaunt their tails," lead author Scott Persons told Discovery News, adding that many of these dinosaurs also had arm fans and head crests, which could have been part of such eye-catching moments.
"I suspect that a displaying oviraptor would be quite a sight, but the precise choreography of a dinosaur mating dance is the sort of thing that you can't learn from bones and is, sadly, the sort of thing that paleontologists will probably never know."
Persons, a researcher at the University of Alberta, and his team, however, were able to tell a lot about the dinosaurs’ appearance and behavior based on fossil evidence.
The scientists noticed that individual vertebrae at the base of an early oviraptor Similicaudiptery and related species were short and numerous, indicating great flexibility. Based on dissections of modern reptile and bird tales, a reconstruction of the dinosaur’s tail muscles revealed oviraptors had what it took to really shake their tail feathers.
Large muscles would have extended far down the tail, having a sufficient number of broad connection points to propel the dinosaur's tail feathers vigorously from side to side and up and down.
Modern-day peacocks and turkeys use their tail plumage in a similar way. It's possible that some oviraptor feathers were as beautiful and striking as those of peacocks.
"Exceptional fossils of oviraptors from China, which were preserved in fine volcanic ash, show definitively that at least some of the tail feathers had bands of contrasting color," Persons explained. "They may have had iridescent feathers, like a peacock, but that is a harder question, and one without definitive evidence."
As for today's birds that use tail plumage to attract mates, the researchers suspect males did most of the feather flaunting and displaying.
While the timeline for feather evolution is still somewhat of a mystery, the new findings provide intriguing clues.
Oviraptors with tail feather fans date back to over 120 million years, but Persons said that "they already have well developed feathers, so I doubt that they were the first."
He thinks dinosaur feathers initially evolved for insulation, with flight and courtship uses following later. It's even possible that insulating feathers first evolved in the reptilian ancestors of dinosaurs.
"The oldest fossil feathers are nearly 160 million years old, but feathers must have evolved many millions of years before that," he said.
Read more at Discovery News
Curiosity Spots Mystery Mars 'Flower'
While using its robotic arm-mounted Mars Hand Lens Imager (MAHLI) camera to take some close up photos of the surface of a rocky outcrop at a location dubbed "Yellowknife Bay" on Dec. 19 (sol 132 of the mission), a bright object could be seen in one of the raw images uploaded to the mission's website. Its discovery has caused quite a stir on AboveTopSecret.com where it was first reported.
Alerted to the mystery feature, MSNBC's Alan Boyle assumed it was just another piece of litter accidentally dropped from the rover. However, this isn't the case. On putting the question to NASA spokesman Guy Webster, it appears initial analysis has confirmed it is part of the rock and not something dropped on top.
"That appears to be part of the rock, not debris from the spacecraft," Webster told Boyle in an email.
So what could it be? The high-resolution MAHLI camera is intended to snap close-up observations of Mars surface features -- acting like hand lens magnifiers used by geologists in the field. Therefore, the object -- that, as noted by Boyle, is shaped like a tiny 'flower' -- is pretty small.
Naturally, the ever-optimistic and irrational part of my brain wants this to be evidence of some kind of Mars fossil, but in all likelihood, it's a concentration of minerals embedded in the rock. The former may sound more exciting, but the latter is the most likely explanation.
The human brain often attaches significance to random shapes, concluding that if it looks like a flower on Mars, then it must be something biological. This is a psychological phenomenon known as "pareidolia" -- and Mars is a very fertile environment for fooling our brains with random shapes.
Read more at Discovery News
Alerted to the mystery feature, MSNBC's Alan Boyle assumed it was just another piece of litter accidentally dropped from the rover. However, this isn't the case. On putting the question to NASA spokesman Guy Webster, it appears initial analysis has confirmed it is part of the rock and not something dropped on top.
"That appears to be part of the rock, not debris from the spacecraft," Webster told Boyle in an email.
So what could it be? The high-resolution MAHLI camera is intended to snap close-up observations of Mars surface features -- acting like hand lens magnifiers used by geologists in the field. Therefore, the object -- that, as noted by Boyle, is shaped like a tiny 'flower' -- is pretty small.
Naturally, the ever-optimistic and irrational part of my brain wants this to be evidence of some kind of Mars fossil, but in all likelihood, it's a concentration of minerals embedded in the rock. The former may sound more exciting, but the latter is the most likely explanation.
The human brain often attaches significance to random shapes, concluding that if it looks like a flower on Mars, then it must be something biological. This is a psychological phenomenon known as "pareidolia" -- and Mars is a very fertile environment for fooling our brains with random shapes.
Read more at Discovery News
Record Temperature Set: Colder than Absolute Zero
Absolute zero is often thought to be the coldest temperature possible. But now researchers show they can achieve even lower temperatures for a strange realm of "negative temperatures."
Oddly, another way to look at these negative temperatures is to consider them hotter than infinity, researchers added.
This unusual advance could lead to new engines that could technically be more than 100 percent efficient, and shed light on mysteries such as dark energy, the mysterious substance that is apparently pulling our universe apart.
An object's temperature is a measure of how much its atoms move — the colder an object is, the slower the atoms are. At the physically impossible-to-reach temperature of zero kelvin, or minus 459.67 degrees Fahrenheit (minus 273.15 degrees Celsius), atoms would stop moving. As such, nothing can be colder than absolute zero on the Kelvin scale.
Bizarro negative temperatures
To comprehend the negative temperatures scientists have now devised, one might think of temperature as existing on a scale that is actually a loop, not linear. Positive temperatures make up one part of the loop, while negative temperatures make up the other part. When temperatures go either below zero or above infinity on the positive region of this scale, they end up in negative territory.
With positive temperatures, atoms more likely occupy low-energy states than high-energy states, a pattern known as Boltzmann distribution in physics. When an object is heated, its atoms can reach higher energy levels.
At absolute zero, atoms would occupy the lowest energy state. At an infinite temperature, atoms would occupy all energy states. Negative temperatures then are the opposite of positive temperatures — atoms more likely occupy high-energy states than low-energy states.
"The inverted Boltzmann distribution is the hallmark of negative absolute temperature, and this is what we have achieved," said researcher Ulrich Schneider, a physicist at the University of Munich in Germany. "Yet the gas is not colder than zero kelvin, but hotter. It is even hotter than at any positive temperature — the temperature scale simply does not end at infinity, but jumps to negative values instead."
As one might expect, objects with negative temperatures behave in very odd ways. For instance, energy typically flows from objects with a higher positive temperature to ones with a lower positive temperature — that is, hotter objects heat up cooler objects, and colder objects cool down hotter ones, until they reach a common temperature. However, energy will always flow from objects with negative temperature to ones with positive temperatures. In this sense, objects with negative temperatures are always hotter than ones with positive temperatures.
Another odd consequence of negative temperatures has to do with entropy, which is a measure of how disorderly a system is. When objects with positive temperature release energy, they increase the entropy of things around them, making them behave more chaotically. However, when objects with negative temperatures release energy, they can actually absorb entropy.
Negative temperatures would be thought impossible, since there is typically no upper bound for how much energy atoms can have, as far as theory currently suggests. (There is a limit to what speed they can travel — according to Einstein's theory of relativity, nothing can accelerate to speeds faster than light.)
Wacky physics experiment
To generate negative temperatures, scientists created a system where atoms do have a limit to how much energy they can possess. They first cooled about 100,000 atoms to a positive temperature of a few nanokelvin, or billionth of a kelvin. They cooled the atoms within a vacuum chamber, which isolated them from any environmental influence that could potentially heat them up accidentally. They also used a web of laser beams and magnetic fields to very precisely control how these atoms behaved, helping to push them into a new temperature realm.
"The temperatures we achieved are negative nanokelvin," Schneider told LiveScience.
Temperature depends on how much atoms move — how much kinetic energy they have. The web of laser beams created a perfectly ordered array of millions of bright spots of light, and in this "optical lattice," atoms could still move, but their kinetic energy was limited.
Temperature also depends on how much potential energy atoms have, and how much energy lies in the interactions between the atoms. The researchers used the optical lattice to limit how much potential energy the atoms had, and they used magnetic fields to very finely control the interactions between atoms, making them either attractive or repulsive.
Temperature is linked with pressure — the hotter something is, the more it expands outward, and the colder something is, the more it contracts inward. To make sure this gas had a negative temperature, the researchers had to give it a negative pressure as well, tinkering with the interactions between atoms until they attracted each other more than they repelled each other.
"We have created the first negative absolute temperature state for moving particles," said researcher Simon Braun at the University of Munich in Germany.
New kinds of engines
Negative temperatures could be used to create heat engines — engines that convert heat energy to mechanical work, such as combustion engines — that are more than 100-percent efficient, something seemingly impossible. Such engines would essentially not only absorb energy from hotter substances, but also colder ones. As such, the work the engine performed could be larger than the energy taken from the hotter substance alone.
Negative temperatures might also help shed light on one of the greatest mysteries in science. Scientists had expected the gravitational pull of matter to slow down the universe's expansion after the Big Bang, eventually bringing it to a dead stop or even reversing it for a "Big Crunch." However, the universe's expansion is apparently speeding up, accelerated growth that cosmologists suggest may be due to dark energy, an as-yet-unknown substance that could make up more than 70 percent of the cosmos.
In much the same way, the negative pressure of the cold gas the researchers created should make it collapse. However, its negative temperature keeps it from doing so. As such, negative temperatures might have interesting parallels with dark energy that may help scientists understand this enigma.
Read more at Discovery News
Oddly, another way to look at these negative temperatures is to consider them hotter than infinity, researchers added.
This unusual advance could lead to new engines that could technically be more than 100 percent efficient, and shed light on mysteries such as dark energy, the mysterious substance that is apparently pulling our universe apart.
An object's temperature is a measure of how much its atoms move — the colder an object is, the slower the atoms are. At the physically impossible-to-reach temperature of zero kelvin, or minus 459.67 degrees Fahrenheit (minus 273.15 degrees Celsius), atoms would stop moving. As such, nothing can be colder than absolute zero on the Kelvin scale.
Bizarro negative temperatures
To comprehend the negative temperatures scientists have now devised, one might think of temperature as existing on a scale that is actually a loop, not linear. Positive temperatures make up one part of the loop, while negative temperatures make up the other part. When temperatures go either below zero or above infinity on the positive region of this scale, they end up in negative territory.
With positive temperatures, atoms more likely occupy low-energy states than high-energy states, a pattern known as Boltzmann distribution in physics. When an object is heated, its atoms can reach higher energy levels.
At absolute zero, atoms would occupy the lowest energy state. At an infinite temperature, atoms would occupy all energy states. Negative temperatures then are the opposite of positive temperatures — atoms more likely occupy high-energy states than low-energy states.
"The inverted Boltzmann distribution is the hallmark of negative absolute temperature, and this is what we have achieved," said researcher Ulrich Schneider, a physicist at the University of Munich in Germany. "Yet the gas is not colder than zero kelvin, but hotter. It is even hotter than at any positive temperature — the temperature scale simply does not end at infinity, but jumps to negative values instead."
As one might expect, objects with negative temperatures behave in very odd ways. For instance, energy typically flows from objects with a higher positive temperature to ones with a lower positive temperature — that is, hotter objects heat up cooler objects, and colder objects cool down hotter ones, until they reach a common temperature. However, energy will always flow from objects with negative temperature to ones with positive temperatures. In this sense, objects with negative temperatures are always hotter than ones with positive temperatures.
Another odd consequence of negative temperatures has to do with entropy, which is a measure of how disorderly a system is. When objects with positive temperature release energy, they increase the entropy of things around them, making them behave more chaotically. However, when objects with negative temperatures release energy, they can actually absorb entropy.
Negative temperatures would be thought impossible, since there is typically no upper bound for how much energy atoms can have, as far as theory currently suggests. (There is a limit to what speed they can travel — according to Einstein's theory of relativity, nothing can accelerate to speeds faster than light.)
Wacky physics experiment
To generate negative temperatures, scientists created a system where atoms do have a limit to how much energy they can possess. They first cooled about 100,000 atoms to a positive temperature of a few nanokelvin, or billionth of a kelvin. They cooled the atoms within a vacuum chamber, which isolated them from any environmental influence that could potentially heat them up accidentally. They also used a web of laser beams and magnetic fields to very precisely control how these atoms behaved, helping to push them into a new temperature realm.
"The temperatures we achieved are negative nanokelvin," Schneider told LiveScience.
Temperature depends on how much atoms move — how much kinetic energy they have. The web of laser beams created a perfectly ordered array of millions of bright spots of light, and in this "optical lattice," atoms could still move, but their kinetic energy was limited.
Temperature also depends on how much potential energy atoms have, and how much energy lies in the interactions between the atoms. The researchers used the optical lattice to limit how much potential energy the atoms had, and they used magnetic fields to very finely control the interactions between atoms, making them either attractive or repulsive.
Temperature is linked with pressure — the hotter something is, the more it expands outward, and the colder something is, the more it contracts inward. To make sure this gas had a negative temperature, the researchers had to give it a negative pressure as well, tinkering with the interactions between atoms until they attracted each other more than they repelled each other.
"We have created the first negative absolute temperature state for moving particles," said researcher Simon Braun at the University of Munich in Germany.
New kinds of engines
Negative temperatures could be used to create heat engines — engines that convert heat energy to mechanical work, such as combustion engines — that are more than 100-percent efficient, something seemingly impossible. Such engines would essentially not only absorb energy from hotter substances, but also colder ones. As such, the work the engine performed could be larger than the energy taken from the hotter substance alone.
Negative temperatures might also help shed light on one of the greatest mysteries in science. Scientists had expected the gravitational pull of matter to slow down the universe's expansion after the Big Bang, eventually bringing it to a dead stop or even reversing it for a "Big Crunch." However, the universe's expansion is apparently speeding up, accelerated growth that cosmologists suggest may be due to dark energy, an as-yet-unknown substance that could make up more than 70 percent of the cosmos.
In much the same way, the negative pressure of the cold gas the researchers created should make it collapse. However, its negative temperature keeps it from doing so. As such, negative temperatures might have interesting parallels with dark energy that may help scientists understand this enigma.
Read more at Discovery News
Jan 3, 2013
Rare Water-Rich Mars Meteorite Discovered
A rare Martian meteorite recently found in Morocco contains minerals with 10 times more water than previously discovered Mars meteorites, a finding that raises new questions about when and how long the planet most like Earth in the solar system had conditions suitable for life.
The rock is believed to be similar to those studied by NASA's Spirit and Opportunity rovers, which landed on opposite sides of Mars in 2004 to look for signs of past water. Spirit is no longer operational, but in August Opportunity was joined by the new and more sophisticated Curiosity rover, which will be searching for chemistry and environmental conditions necessary to support microbial life.
The meteorite, known as Northwest Africa (NWA) 7034, is the second-oldest of 110 named stones originating from Mars that have been retrieved on Earth. Purchased from a Moroccan meteorite dealer in 2011, the black, baseball-sized stone, which weighs less than 1 pound, is 2.1 billon years old, meaning it formed during what is known as the early Amazonian era in Mars' geologic history.
"It's from a time on Mars that we actually don't know much about," geologist Carl Agee, with the University of New Mexico in Albuquerque, told Discovery News.
The only older Mars meteorite found so far is the 4-billion-year-old Allan Hills 84001 Antarctica stone that was the source of speculation about microfossils in 1996.
Early Mars was believed to be warm and wet, but the planet lost most of its atmosphere and its surface water to become a cold, dry desert that appears today.
"The time from when our meteorite is from is maybe a transitional period in the climate, when Mars was losing its atmosphere, losing its water on the surface," Agee said.
The meteorite is relatively rich in water -- about 6,000 parts per million -- compared with typical Martian meteorites that contain about 200- to 300 parts per million. It is similar to basaltic rocks on Earth that form in volcanic eruptions.
"The fact that this meteorite formed in the presence of water suggests that maybe this water hung around for a while, maybe a bit longer than previously thought. It at least opens our minds to the idea that maybe Mars climate change was more transitional, rather than an abrupt loss of atmosphere and water," Agee said.
Like other Mars meteorites, NWA 7034, nicknamed "Black Beauty," also contains tiny bits of carbon, formed from geologic, not biological activity, said Andrew Steele, who studies Mars meteorites at the Carnegie Institution of Washington DC.
Steele, who also is a member of the Curiosity science team, would like to do more analysis on the meteorite with instruments that are similar to those on the rover.
Scientists don't know why more meteorites like Black Beauty haven't been found on Earth. The period of time from which they originated may be relatively short, or most may not survive the trip through Earth's atmosphere.
"(Mars meteorites) are tough, but by the time they get here they're quite friable and brittle," Steele told Discovery News.
"This one does look completely different," he added. "It's jet black. The others are slightly greenish cast."
Read more at Discovery News
The rock is believed to be similar to those studied by NASA's Spirit and Opportunity rovers, which landed on opposite sides of Mars in 2004 to look for signs of past water. Spirit is no longer operational, but in August Opportunity was joined by the new and more sophisticated Curiosity rover, which will be searching for chemistry and environmental conditions necessary to support microbial life.
The meteorite, known as Northwest Africa (NWA) 7034, is the second-oldest of 110 named stones originating from Mars that have been retrieved on Earth. Purchased from a Moroccan meteorite dealer in 2011, the black, baseball-sized stone, which weighs less than 1 pound, is 2.1 billon years old, meaning it formed during what is known as the early Amazonian era in Mars' geologic history.
"It's from a time on Mars that we actually don't know much about," geologist Carl Agee, with the University of New Mexico in Albuquerque, told Discovery News.
The only older Mars meteorite found so far is the 4-billion-year-old Allan Hills 84001 Antarctica stone that was the source of speculation about microfossils in 1996.
Early Mars was believed to be warm and wet, but the planet lost most of its atmosphere and its surface water to become a cold, dry desert that appears today.
"The time from when our meteorite is from is maybe a transitional period in the climate, when Mars was losing its atmosphere, losing its water on the surface," Agee said.
The meteorite is relatively rich in water -- about 6,000 parts per million -- compared with typical Martian meteorites that contain about 200- to 300 parts per million. It is similar to basaltic rocks on Earth that form in volcanic eruptions.
"The fact that this meteorite formed in the presence of water suggests that maybe this water hung around for a while, maybe a bit longer than previously thought. It at least opens our minds to the idea that maybe Mars climate change was more transitional, rather than an abrupt loss of atmosphere and water," Agee said.
Like other Mars meteorites, NWA 7034, nicknamed "Black Beauty," also contains tiny bits of carbon, formed from geologic, not biological activity, said Andrew Steele, who studies Mars meteorites at the Carnegie Institution of Washington DC.
Steele, who also is a member of the Curiosity science team, would like to do more analysis on the meteorite with instruments that are similar to those on the rover.
Scientists don't know why more meteorites like Black Beauty haven't been found on Earth. The period of time from which they originated may be relatively short, or most may not survive the trip through Earth's atmosphere.
"(Mars meteorites) are tough, but by the time they get here they're quite friable and brittle," Steele told Discovery News.
"This one does look completely different," he added. "It's jet black. The others are slightly greenish cast."
Read more at Discovery News
Hairy Eyeball Caused by Rare Tumor
A rare tumor in a 19-year old man caused hair to grow on his eyeball, researchers report.
The tumor, called a limbal dermoid, was benign and had been present since birth. It gradually grew in size until it was about 5 mm in diameter (a little less than a quarter of an inch), and sprouted several black hairs, said the researchers from Tabriz University of Medical Sciences in Iran.
Limbal dermoids are uncommon -- an eye doctor may see just one or two cases during his career, said Dr. Mark Fromer, director of Fromer Eye Centers in New York City and an ophthalmologist at Lenox Hill Hospital, who is not involved in the Iranian man's care. These tumors contain tissue normally found in another part of the body. Most frequently, limbal dermoids contain hair follicles, but they can also contain other tissues, including cartilage and sweat glands, Fromer said.
These tumors can cause astigmatism (blurred vision), but usually don't cause dramatic vision problems, Fromer said. That's because they typically do not cover the center of the cornea, an important part of the eye for vision, he said.
Limbal dermoids can be removed for cosmetic reasons, but their removal typically doesn't change patients' eyesight, Fromer said.
Fromer currently has a female patient with a limbal dermoid that contains hairs, but she does not want it removed. "It hasn't grown or changed and it doesn't physically bother her," Former said.
Read more at Discovery News
The tumor, called a limbal dermoid, was benign and had been present since birth. It gradually grew in size until it was about 5 mm in diameter (a little less than a quarter of an inch), and sprouted several black hairs, said the researchers from Tabriz University of Medical Sciences in Iran.
Limbal dermoids are uncommon -- an eye doctor may see just one or two cases during his career, said Dr. Mark Fromer, director of Fromer Eye Centers in New York City and an ophthalmologist at Lenox Hill Hospital, who is not involved in the Iranian man's care. These tumors contain tissue normally found in another part of the body. Most frequently, limbal dermoids contain hair follicles, but they can also contain other tissues, including cartilage and sweat glands, Fromer said.
These tumors can cause astigmatism (blurred vision), but usually don't cause dramatic vision problems, Fromer said. That's because they typically do not cover the center of the cornea, an important part of the eye for vision, he said.
Limbal dermoids can be removed for cosmetic reasons, but their removal typically doesn't change patients' eyesight, Fromer said.
Fromer currently has a female patient with a limbal dermoid that contains hairs, but she does not want it removed. "It hasn't grown or changed and it doesn't physically bother her," Former said.
Read more at Discovery News
Remains of Nazi Goering's Wife Identified
Swedish scientists have solved the mystery over a a zinc coffin found 21 years ago at the German estate of Hitler's right-hand man, Hermann Göring, by identifying the skeletal remains as those of Göring's first wife Carin.
Born in Stockholm, Sweden, Carin Fock married the decorated pilot Hermann Göring in 1923. The couple settled in Germany, where Carin enjoyed a high social status as the wife of a central leader in the growing National Socialist German Workers' Party (NSDAP).
"Adolf Hitler liked her. She has been called the mascot of the Nazi party," Marie Allen, professor of forensic genetics at Uppsala University, Sweden, and colleagues wrote in the journal PLoS ONE.
But Carin Göring suffered from heart problems, and in 1931, during a visit in Sweden, she died at 42. She was buried in the family tomb at Lovön, on the island Ekerö outside Stockholm.
Three years later, Göring moved the remains to his country retreat near Berlin, Carinhall, named after his wife.
"The funeral, worthy of a statesman, was a propaganda success, with all the most prominent Nazi leaders attending, including Hitler," wrote the researchers.
"The original coffin was placed in a coffin made of zinc and this in turn was placed in a tin coffin," they added.
The most pompous among the estates owned by the Nazi elite, Carinhall was filled with looted artworks, and indeed housed the biggest private collection in the world.
It was here that Göring plotted the formation of the Gestapo, the logistics of the the first concentration camps in Germany, and the bombing of European cities in World War II.
As the Russian army advanced at the end of the war, the Nazi leader sent his looted artworks to salt mines and small towns around the country. Some artworks were destroyed in the process, while others were discovered by advancing Allied troops towards the end of the war.
Then, in 1945, Göring ordered the destruction of Carinhall. Convicted of war crimes and crimes against humanity at the Nuremberg Trials, he swallowed cyanide hours before his scheduled hanging on Oct. 15, 1946.
The fate of Carin's grave remained a mystery for decades.
In 1951 skeletal parts described as "not more than a human torso" were found near Carinhall. Thought to come from Carin Göring, they were cremated and buried in the family tomb in Sweden.
Forty years later, in 1991, treasure hunters swooping on the ruins of Carinhall found a casket with other skeletal remains. They were sent to Sweden and the National Board of Forensic Medicine for identification.
Using state-of-the-art technologies, Allen and colleagues examined a total of 26 bones. DNA analysis established that they belonged to an adult woman.
Most importantly, a comparison of mitochondrial DNA, which is transmitted from mother to child, showed identical DNA sequences between the skeletal remains and Thomas Kantzow, Carin’s son from a previous marriage.
Read more at Discovery News
Born in Stockholm, Sweden, Carin Fock married the decorated pilot Hermann Göring in 1923. The couple settled in Germany, where Carin enjoyed a high social status as the wife of a central leader in the growing National Socialist German Workers' Party (NSDAP).
"Adolf Hitler liked her. She has been called the mascot of the Nazi party," Marie Allen, professor of forensic genetics at Uppsala University, Sweden, and colleagues wrote in the journal PLoS ONE.
But Carin Göring suffered from heart problems, and in 1931, during a visit in Sweden, she died at 42. She was buried in the family tomb at Lovön, on the island Ekerö outside Stockholm.
Three years later, Göring moved the remains to his country retreat near Berlin, Carinhall, named after his wife.
"The funeral, worthy of a statesman, was a propaganda success, with all the most prominent Nazi leaders attending, including Hitler," wrote the researchers.
"The original coffin was placed in a coffin made of zinc and this in turn was placed in a tin coffin," they added.
The most pompous among the estates owned by the Nazi elite, Carinhall was filled with looted artworks, and indeed housed the biggest private collection in the world.
It was here that Göring plotted the formation of the Gestapo, the logistics of the the first concentration camps in Germany, and the bombing of European cities in World War II.
As the Russian army advanced at the end of the war, the Nazi leader sent his looted artworks to salt mines and small towns around the country. Some artworks were destroyed in the process, while others were discovered by advancing Allied troops towards the end of the war.
Then, in 1945, Göring ordered the destruction of Carinhall. Convicted of war crimes and crimes against humanity at the Nuremberg Trials, he swallowed cyanide hours before his scheduled hanging on Oct. 15, 1946.
The fate of Carin's grave remained a mystery for decades.
In 1951 skeletal parts described as "not more than a human torso" were found near Carinhall. Thought to come from Carin Göring, they were cremated and buried in the family tomb in Sweden.
Forty years later, in 1991, treasure hunters swooping on the ruins of Carinhall found a casket with other skeletal remains. They were sent to Sweden and the National Board of Forensic Medicine for identification.
Using state-of-the-art technologies, Allen and colleagues examined a total of 26 bones. DNA analysis established that they belonged to an adult woman.
Most importantly, a comparison of mitochondrial DNA, which is transmitted from mother to child, showed identical DNA sequences between the skeletal remains and Thomas Kantzow, Carin’s son from a previous marriage.
Read more at Discovery News
Deepest Corals in Great Barrier Reef Discovered
Even four times as deep as most scuba divers venture, the Great Barrier Reef blooms. A new exploration by a remote-operated submersible has found the reef's deepest coral yet.
The common coral Acropora is living 410 feet (125 meters) below the ocean's surface, a discovery that expedition leader Pim Bongaerts of the University of Queensland called "mind-blowing." The group had previously seen the coral living in the reef at a depth of about 200 feet (60 m).
Coral reefs are made of colonies of polyps which secret a rock-like exoskeleton. The polyps have a symbiotic relationship with algae that provide them nutrients using photosynthesis. Because this process requires light, coral reefs thrive in clear, relatively shallow water.
"The discovery shows that there are coral communities on the Great Barrier Reef existing at considerably greater depths than we could have ever imagined," Bongaerts said in a statement.
Coral colonies
The 410-foot distance is surprising for the Great Barrier Reef, where scuba divers find stunning coral displays at depths down to 100 feet. But corals are known to live deep elsewhere. In the Gulf of Mexico, researchers have found the coral Lophelia pertusa thriving 2,620 feet (799 m) down. Lophelia doesn't need sunlight to survive. In Puerto Rico, light-dependent corals survive as far down as 500 feet (150 m).
Bongaerts and his colleagues received funding from insurer the Catlin Group Limited to explore the Great Barrier Reef as part of an effort to understand how climate change is altering the oceans.
On the outer edge of the Ribbon Reefs, off the northern Great Barrier Reef, the researchers hit unusually calm seas and were able to deploy a remote-operated vehicle, or ROV, off the edge of the Australian continental shelf, where the ocean floor plummets hundreds of feet. It was a tough dive, said expedition member Paul Muir, a taxonomist from the Museum of Tropical Queensland.
"With more than 250 meters of cable out to provide power and communications with the ROV, it was a real struggle to collect a specimen of one of these corals," Muir said in a statement.
The deep reef
The team persevered and brought one precious coral sample back to sea level. The specimen was Acropora, a type of coral that makes up the majority of most of the world's reefs. Typically, such corals peter out in the Great Barrier Reef above 330 feet (100 m), replaced by non-light-dependent sponges and sea fans.
"These discoveries show just how little we really know about the reef and how much more is yet to be discovered," Bongaerts said. "This poses lots of questions for us, but now we have specimens, we'll be able to analyze them much more closely and can expect our findings to reveal a far greater understanding of just what is going on to enable reef corals to survive at such extreme depths."
Read more at Discovery News
The common coral Acropora is living 410 feet (125 meters) below the ocean's surface, a discovery that expedition leader Pim Bongaerts of the University of Queensland called "mind-blowing." The group had previously seen the coral living in the reef at a depth of about 200 feet (60 m).
Coral reefs are made of colonies of polyps which secret a rock-like exoskeleton. The polyps have a symbiotic relationship with algae that provide them nutrients using photosynthesis. Because this process requires light, coral reefs thrive in clear, relatively shallow water.
"The discovery shows that there are coral communities on the Great Barrier Reef existing at considerably greater depths than we could have ever imagined," Bongaerts said in a statement.
Coral colonies
The 410-foot distance is surprising for the Great Barrier Reef, where scuba divers find stunning coral displays at depths down to 100 feet. But corals are known to live deep elsewhere. In the Gulf of Mexico, researchers have found the coral Lophelia pertusa thriving 2,620 feet (799 m) down. Lophelia doesn't need sunlight to survive. In Puerto Rico, light-dependent corals survive as far down as 500 feet (150 m).
Bongaerts and his colleagues received funding from insurer the Catlin Group Limited to explore the Great Barrier Reef as part of an effort to understand how climate change is altering the oceans.
On the outer edge of the Ribbon Reefs, off the northern Great Barrier Reef, the researchers hit unusually calm seas and were able to deploy a remote-operated vehicle, or ROV, off the edge of the Australian continental shelf, where the ocean floor plummets hundreds of feet. It was a tough dive, said expedition member Paul Muir, a taxonomist from the Museum of Tropical Queensland.
"With more than 250 meters of cable out to provide power and communications with the ROV, it was a real struggle to collect a specimen of one of these corals," Muir said in a statement.
The deep reef
The team persevered and brought one precious coral sample back to sea level. The specimen was Acropora, a type of coral that makes up the majority of most of the world's reefs. Typically, such corals peter out in the Great Barrier Reef above 330 feet (100 m), replaced by non-light-dependent sponges and sea fans.
"These discoveries show just how little we really know about the reef and how much more is yet to be discovered," Bongaerts said. "This poses lots of questions for us, but now we have specimens, we'll be able to analyze them much more closely and can expect our findings to reveal a far greater understanding of just what is going on to enable reef corals to survive at such extreme depths."
Read more at Discovery News
Jan 2, 2013
Terrace Farming Unearthed at Ancient Desert City of Petra
A team of international archaeologists including Christian Cloke of the University of Cincinnati is providing new insights into successful and extensive water management and agricultural production in and around the ancient desert city of Petra, located in present-day Jordan. Ongoing investigations, of which Cloke is a part, are led by Professor Susan Alcock of the Brown University Petra Archaeological Project (BUPAP).
Using a variety of tools and techniques, including high-resolution satellite imagery and optically stimulated luminescence (OSL) dating of soils, Cloke, a doctoral student in the Department of Classics at UC, and Cecelia Feldman, classics lecturer at UMass-Amherst, have suggested that extensive terrace farming and dam construction in the region north of the city began around the first century, some 2,000 years ago, not during the Iron Age (c. 1200-300 BC) as had been previously hypothesized. This striking development, it seems, was due to the ingenuity and enterprise of the ancient Nabataeans, whose prosperous kingdom had its capital at Petra until the beginning of the second century.
The successful terrace farming of wheat, grapes and possibly olives, resulted in a vast, green, agricultural "suburb" to Petra in an otherwise inhospitable, arid landscape. This terrace farming remained extensive and robust through the third century. Based on surface finds and comparative data collected by other researchers in the area, however, it is clear that this type of farming continued to some extent for many centuries, until the end of the first millennium (between A.D. 800 and 1000). That ancient Petra was under extensive cultivation is a testament to past strategies of land management, and is all the more striking in light of the area's dry and dusty environment today.
Cloke and Feldman will present their findings Jan. 4 at the Archaeological Institute of America Annual Meeting in Seattle, in a paper titled "On the Rocks: Landscape Modification and Archaeological Features in Petra's Hinterland." Their research efforts are contributing to a growing understanding of the city, its road networks, and life in the surrounding area.
Agricultural Success Followed by Annexation
Dating the start of extensive terrace farming at Petra to the beginning of the common era has important historical implications, according to Cloke, because this date coincides closely with the Roman annexation of the Nabataean Kingdom in A.D. 106.
He explained, "No doubt the explosion of agricultural activity in the first century and the increased wealth that resulted from the wine and oil production made Petra an exceptionally attractive prize for Rome. The region around Petra not only grew enough food to meet its own needs, but also would have been able to provide olives, olive oil, grapes and wine for trade. This robust agricultural production would have made the region a valuable asset for supplying Roman forces on the empire's eastern frontier."
In other words, said Feldman, successful terrace farming and water management when Petra was at its zenith as a trading center added not only to the city's economic importance but to its strategic military value as well, because there were limited options in the region for supplying troops with essential supplies.
Terraces for Farming and Dams for Water Management
On large stretches of land north of Petra, inhabitants built complex and extensive systems to dam wadis (riverbeds) and redirect winter rainwater to hillside terraces used for farming.
Rainfall in the region occurs only between October and March, often in brief, torrential downpours, so it was important for Petra's inhabitants to capture and store all available water for later use during the dry season. Over the centuries, the Nabataeans of Petra became experts at doing so. The broad watershed of sandstone hills naturally directed water flow to the city center, and a complex system of pipes and channels directed it to underground cisterns where it was stored for later use.
"Perhaps most significantly," said Cloke, "it's clear that they had considerable knowledge of their surrounding topography and climate. The Nabataeans differentiated watersheds and the zones of use for water: water collected and stored in the city itself was not cannibalized for agricultural uses. The city's administrators clearly distinguished water serving the city's needs from water to be redirected and accumulated for nurturing crops. Thus, extensive farming activity was almost entirely outside the bounds of the city's natural catchment area and utilized separate watersheds and systems of runoff."
Read more at Science Daily
Using a variety of tools and techniques, including high-resolution satellite imagery and optically stimulated luminescence (OSL) dating of soils, Cloke, a doctoral student in the Department of Classics at UC, and Cecelia Feldman, classics lecturer at UMass-Amherst, have suggested that extensive terrace farming and dam construction in the region north of the city began around the first century, some 2,000 years ago, not during the Iron Age (c. 1200-300 BC) as had been previously hypothesized. This striking development, it seems, was due to the ingenuity and enterprise of the ancient Nabataeans, whose prosperous kingdom had its capital at Petra until the beginning of the second century.
The successful terrace farming of wheat, grapes and possibly olives, resulted in a vast, green, agricultural "suburb" to Petra in an otherwise inhospitable, arid landscape. This terrace farming remained extensive and robust through the third century. Based on surface finds and comparative data collected by other researchers in the area, however, it is clear that this type of farming continued to some extent for many centuries, until the end of the first millennium (between A.D. 800 and 1000). That ancient Petra was under extensive cultivation is a testament to past strategies of land management, and is all the more striking in light of the area's dry and dusty environment today.
Cloke and Feldman will present their findings Jan. 4 at the Archaeological Institute of America Annual Meeting in Seattle, in a paper titled "On the Rocks: Landscape Modification and Archaeological Features in Petra's Hinterland." Their research efforts are contributing to a growing understanding of the city, its road networks, and life in the surrounding area.
Agricultural Success Followed by Annexation
Dating the start of extensive terrace farming at Petra to the beginning of the common era has important historical implications, according to Cloke, because this date coincides closely with the Roman annexation of the Nabataean Kingdom in A.D. 106.
He explained, "No doubt the explosion of agricultural activity in the first century and the increased wealth that resulted from the wine and oil production made Petra an exceptionally attractive prize for Rome. The region around Petra not only grew enough food to meet its own needs, but also would have been able to provide olives, olive oil, grapes and wine for trade. This robust agricultural production would have made the region a valuable asset for supplying Roman forces on the empire's eastern frontier."
In other words, said Feldman, successful terrace farming and water management when Petra was at its zenith as a trading center added not only to the city's economic importance but to its strategic military value as well, because there were limited options in the region for supplying troops with essential supplies.
Terraces for Farming and Dams for Water Management
On large stretches of land north of Petra, inhabitants built complex and extensive systems to dam wadis (riverbeds) and redirect winter rainwater to hillside terraces used for farming.
Rainfall in the region occurs only between October and March, often in brief, torrential downpours, so it was important for Petra's inhabitants to capture and store all available water for later use during the dry season. Over the centuries, the Nabataeans of Petra became experts at doing so. The broad watershed of sandstone hills naturally directed water flow to the city center, and a complex system of pipes and channels directed it to underground cisterns where it was stored for later use.
"Perhaps most significantly," said Cloke, "it's clear that they had considerable knowledge of their surrounding topography and climate. The Nabataeans differentiated watersheds and the zones of use for water: water collected and stored in the city itself was not cannibalized for agricultural uses. The city's administrators clearly distinguished water serving the city's needs from water to be redirected and accumulated for nurturing crops. Thus, extensive farming activity was almost entirely outside the bounds of the city's natural catchment area and utilized separate watersheds and systems of runoff."
Read more at Science Daily
How Some Medieval Cultures Adapted to Rise of Islam
Medieval Afghanistan, Iran and the one-time Soviet Central Asian states were frontiers in flux as the Islamic Caliphate spread beyond the Arabian Peninsula in the seventh through 10th centuries.
As such, different groups, such as the new Arab ruling class, the native landed gentry and local farmers, jockeyed for power, position and economic advantage over an approximately 300-year period as the Sasanian Empire collapsed and the Caliphate took its place.
University of Cincinnati historian Robert Haug, assistant professor, will present his research on how social, cultural and political changes were manifested in these border areas that serve almost as a "perpetual frontier." He does so Jan. 3, 2013, at the American Historical Association, in a presentation titled "Between the Limits and the Gaps: Conceptualizing Frontiers in Medieval Arabic and Persian Geographies."
While many in the West might perceive these Middle Eastern and Asian countries as Islamic religious monoliths, their populations in the Middle Ages were only about 50 percent Muslim in the 10th century, even after 300 years of Arab rule, according to Haug.
"Some may see these areas as homogenous today, but as the fringes of empire in the Middle Ages, there were economic, cultural, political and religious tensions that were negotiated and re-negotiated," he explained.
For instance, conversion of native populations to Islam was initially discouraged by the new Arab elite. "The incoming Arab elite seeking to solidify power in these frontier border areas wanted to maintain a distinction between themselves and the long-term resident populations. The new elites wanted to be able to collect taxes and fulfill military levies, and there were more strictures on how you went about doing so with co-religionists vs. those who were not Muslim," explained Haug, adding that radical transformation and conversions did not generally take place except at the very top tier of native societies.
In studying records of the era, he also finds how subject populations maneuvered in order to maintain position, economic security or cultural identity in a shifting social climate. For instance, in comparing early ninth century records and texts to those from the late 10th centuries, Haug notes that as the number of mosques in an area increased, the vocabulary for referring to fortified farms also changed.
These were border areas on the edge of the steppes where raiders were a perpetual problem, so farmers and landed gentry wanted to keep their fortified grain silos and farms. However, these fortified enclosures were also seen as a threat by the Caliphate. After all, they could serve to harbor enemies of the Islamic empire. To negotiate this tightrope, village headmen, farmers and the landed gentry began to refer to these defensive enclosures as "ribats," which was not the former local word used, but an Arab term referencing a defensive jihad. So, now, the fortified farms and food storage could be viewed as a means for defending Islam, making them more politically and militarily acceptable to the Arab elites.
Adoption of the term doesn't mean that those using it had necessarily converted to Islam, said Haug, adding, "This had become a mixed culture with overlapping identities. Political and economic necessity likely drove such changes in the vocabulary and culture. It's not unlike how Michigan residents or Minnesotans tend to watch hockey, thus aligning themselves culturally with Canada in this regard; however, they're still U.S. citizens."
The coins minted and used in the frontier areas also speak of the struggle of local elites to retain or expand their power under the Caliphate. "The coins give you information as to who was in charge. I also like to say, 'The coin doesn't lie.' As power shifted back and forth, the names on the coins change," said Haug.
Read more at Science Daily
As such, different groups, such as the new Arab ruling class, the native landed gentry and local farmers, jockeyed for power, position and economic advantage over an approximately 300-year period as the Sasanian Empire collapsed and the Caliphate took its place.
University of Cincinnati historian Robert Haug, assistant professor, will present his research on how social, cultural and political changes were manifested in these border areas that serve almost as a "perpetual frontier." He does so Jan. 3, 2013, at the American Historical Association, in a presentation titled "Between the Limits and the Gaps: Conceptualizing Frontiers in Medieval Arabic and Persian Geographies."
While many in the West might perceive these Middle Eastern and Asian countries as Islamic religious monoliths, their populations in the Middle Ages were only about 50 percent Muslim in the 10th century, even after 300 years of Arab rule, according to Haug.
"Some may see these areas as homogenous today, but as the fringes of empire in the Middle Ages, there were economic, cultural, political and religious tensions that were negotiated and re-negotiated," he explained.
For instance, conversion of native populations to Islam was initially discouraged by the new Arab elite. "The incoming Arab elite seeking to solidify power in these frontier border areas wanted to maintain a distinction between themselves and the long-term resident populations. The new elites wanted to be able to collect taxes and fulfill military levies, and there were more strictures on how you went about doing so with co-religionists vs. those who were not Muslim," explained Haug, adding that radical transformation and conversions did not generally take place except at the very top tier of native societies.
In studying records of the era, he also finds how subject populations maneuvered in order to maintain position, economic security or cultural identity in a shifting social climate. For instance, in comparing early ninth century records and texts to those from the late 10th centuries, Haug notes that as the number of mosques in an area increased, the vocabulary for referring to fortified farms also changed.
These were border areas on the edge of the steppes where raiders were a perpetual problem, so farmers and landed gentry wanted to keep their fortified grain silos and farms. However, these fortified enclosures were also seen as a threat by the Caliphate. After all, they could serve to harbor enemies of the Islamic empire. To negotiate this tightrope, village headmen, farmers and the landed gentry began to refer to these defensive enclosures as "ribats," which was not the former local word used, but an Arab term referencing a defensive jihad. So, now, the fortified farms and food storage could be viewed as a means for defending Islam, making them more politically and militarily acceptable to the Arab elites.
Adoption of the term doesn't mean that those using it had necessarily converted to Islam, said Haug, adding, "This had become a mixed culture with overlapping identities. Political and economic necessity likely drove such changes in the vocabulary and culture. It's not unlike how Michigan residents or Minnesotans tend to watch hockey, thus aligning themselves culturally with Canada in this regard; however, they're still U.S. citizens."
The coins minted and used in the frontier areas also speak of the struggle of local elites to retain or expand their power under the Caliphate. "The coins give you information as to who was in charge. I also like to say, 'The coin doesn't lie.' As power shifted back and forth, the names on the coins change," said Haug.
Read more at Science Daily
Potent Antiobiotic Found in Giant Panda Blood
Giant panda blood may hold the secret to curing superbug illnesses in humans as well as other diseases, according to new research.
The teddy bear-like animals would hardly seem to be associated with industrial strength cleanser and potent antibiotics, but their link with these possible cure alls now appears to have been forged.
The primary component in giant panda blood is called cathelicidin-AM. It was found after analyzing the panda's DNA.
This compound kills bacteria in less than an hour. Other well known antibiotics take more than six hours to tackle the same job.
Xiuwen Yan, who led the research at the Life Sciences College of Nanjing Agricultural University in China, told the London Telegraph: "It showed potential antimicrobial activities against wide spectrum of microorganisms including bacteria and fungi, both standard and drug-resistant strains."
Yan continued, "Under the pressure of increasing microorganisms with drug resistance against conventional antibiotics, there is urgent need to develop new type of antimicrobial agents. Gene-encoded antimicrobial peptides play an important role in innate immunity against noxious microorganisms. They cause much less drug resistance of microbes than conventional antibiotics."
Giant pandas are highly endangered, with only about 1,600 left in the wild. The new discovery shows how important it is to save all species -- plants, insects, birds and animals -- as they could, like the giant panda, hold keys to solving many pressing human health issues.
Thankfully, the scientists don't have to raise a bunch of pandas in order to keep up the supply of cathelicidin-AM. Yan and colleagues have figured out a way to synthesize the compound artificially in a lab. They did this by decoding giant panda genes to produce a small molecule known as a peptide.
Yan explained, "Antimicrobial peptides are important components in innate immunity -- they can provide an effective and fast acting defence against harmful microorganisms. More than 1000 antimicrobial peptides have been found from animals, plants, and microorganisms. Analysis revealed that the panda cathelicidin had the nearest evolution relationship with dog cathelicidin."
Read more at Discovery News
The teddy bear-like animals would hardly seem to be associated with industrial strength cleanser and potent antibiotics, but their link with these possible cure alls now appears to have been forged.
The primary component in giant panda blood is called cathelicidin-AM. It was found after analyzing the panda's DNA.
This compound kills bacteria in less than an hour. Other well known antibiotics take more than six hours to tackle the same job.
Xiuwen Yan, who led the research at the Life Sciences College of Nanjing Agricultural University in China, told the London Telegraph: "It showed potential antimicrobial activities against wide spectrum of microorganisms including bacteria and fungi, both standard and drug-resistant strains."
Yan continued, "Under the pressure of increasing microorganisms with drug resistance against conventional antibiotics, there is urgent need to develop new type of antimicrobial agents. Gene-encoded antimicrobial peptides play an important role in innate immunity against noxious microorganisms. They cause much less drug resistance of microbes than conventional antibiotics."
Giant pandas are highly endangered, with only about 1,600 left in the wild. The new discovery shows how important it is to save all species -- plants, insects, birds and animals -- as they could, like the giant panda, hold keys to solving many pressing human health issues.
Thankfully, the scientists don't have to raise a bunch of pandas in order to keep up the supply of cathelicidin-AM. Yan and colleagues have figured out a way to synthesize the compound artificially in a lab. They did this by decoding giant panda genes to produce a small molecule known as a peptide.
Yan explained, "Antimicrobial peptides are important components in innate immunity -- they can provide an effective and fast acting defence against harmful microorganisms. More than 1000 antimicrobial peptides have been found from animals, plants, and microorganisms. Analysis revealed that the panda cathelicidin had the nearest evolution relationship with dog cathelicidin."
Read more at Discovery News
World's Oldest Fossils Found in Australia
Rocks that grew from bugs? Some of the oldest fossils on the planet are sedimentary rocks that were once living organisms. Western Australia is famous for both living and fossilized examples of these early Earth inhabitants. The most well studied of these microbially-built structures are called stromatolites, and they grow in a wide-range of environments: from the shore, underwater, to inland across arid salt-flats.
The ecosystems that generated Earth's oldest stromatolites also produced other types of what biogeochemist Nora Noffke of Old Dominion University in Norfolk, Va., calls microbially induced sedimentary structures or MISS. "These structures represent an entire ecosystem of surprising diversity," she says. They may even rival stromatolites with fossils dating back 3.49 billion years.
The microbes that built these ancient structures “are the oldest fossils ever described. Those are our oldest ancestors,” Noffke told the Washington Post. She and her team presented their analysis last month at a meeting of the Geological Society of America.
Like stromatolites, these other microbial mats hold minerals and sand particles in their matrix, preventing erosion of the land around them. After they die, the sand eventually turns to sandstone and preserves the mats as fossils.
Noffke and her team looked in Western Australia’s Pilbara region for the community of fossil organisms turned to stone. Their discovery still needs additional scrutiny to confirm the age, but their study illustrates how diverse life was just a billion years after the planet formed.
As the Washington Post reported:
From Discovery News
The ecosystems that generated Earth's oldest stromatolites also produced other types of what biogeochemist Nora Noffke of Old Dominion University in Norfolk, Va., calls microbially induced sedimentary structures or MISS. "These structures represent an entire ecosystem of surprising diversity," she says. They may even rival stromatolites with fossils dating back 3.49 billion years.
The microbes that built these ancient structures “are the oldest fossils ever described. Those are our oldest ancestors,” Noffke told the Washington Post. She and her team presented their analysis last month at a meeting of the Geological Society of America.
Like stromatolites, these other microbial mats hold minerals and sand particles in their matrix, preventing erosion of the land around them. After they die, the sand eventually turns to sandstone and preserves the mats as fossils.
Noffke and her team looked in Western Australia’s Pilbara region for the community of fossil organisms turned to stone. Their discovery still needs additional scrutiny to confirm the age, but their study illustrates how diverse life was just a billion years after the planet formed.
As the Washington Post reported:
“It’s not just finding this stuff that’s interesting,” says Alan Decho, a geobiologist at the University of South Carolina’s Arnold School of Public Health. “It’s showing that the life had some organization to it.” Ridges that crisscross the rocks like strands in a spider web hint that primitive bacteria linked up in sprawling networks. Like their modern counterparts, they may have lived in the equivalent of microbial cities that hosted thousands of kinds of bacteria, each specialized for a different task and communicating with the others via chemical signals.
From Discovery News
Jan 1, 2013
Dried Squash Holds Headless King's Blood
Two centuries after the French people beheaded Louis XVI and dipped their handkerchiefs in his blood, scientists believe they have authenticated the remains of one such rag kept as a revolutionary souvenir.
Researchers have been trying for years to verify a claim imprinted on an ornately decorated calabash that it contains a sample of the blood of the French king guillotined in Paris on January 21, 1793.
The dried, hollowed squash is adorned with portraits of revolutionary heroes and the text: "On January 21, Maximilien Bourdaloue dipped his handkerchief in the blood of Louis XVI after his decapitation".
He is then believed to have placed the fabric in the gourd, and had it embellished.
The sinister souvenir has been in the private hands of an Italian family for more than a century, said the team of experts from Spain and France which published its findings in the journal Forensic Science International.
Two years ago, analysis of DNA taken from blood traces found inside the ornate vegetable revealed a likely match for someone of Louis' description, including his blue eyes.
But not having the DNA of any kingly relation, researchers could not prove beyond doubt that the blood belonged to Louis.
Until now.
Using the genetic material, the team managed to draw a link to another gruesome artifact -- a mummified head believed to belong to Louis' 16th century predecessor, Henri IV.
In so doing, they provided evidence for authenticating both sets of remains -- uncovering a rare genetic signature shared by two men separated by seven generations.
"This study shows that (the owners of the remains) share a genetic heritage passed on through the paternal line. They have a direct link to one another through their fathers," French forensic pathologist Philippe Charlier said.
The revolution in which Louis and queen Marie-Antoinette lost their heads in public executions also saw mobs ransack the royal chapel at Saint-Denis, north of Paris -- hauling ancient monarchs like Henri from their tombs and mutilating the remains which they tossed into pits.
An individual was recorded to have rescued a severed head from the chaos.
Long thought to belong to Henri, assassinated at the age of 57 by a Catholic fanatic in 1610, the head changed hands several times over the next two centuries, bought and sold at auction or kept in secretive private collections.
Scientists in 2010 said they found proof that the head was indeed Henri's, citing physical features that matched 16th century portraits of the king, as well as radiocarbon dating, 3D scanning and X-rays.
The 2010 study, however, found no DNA and its findings have been contested by some.
With the new evidence, "it is about 250 times more likely that the (owners of the) head and the blood are paternally related, than unrelated," co-author Carles Lalueza Fox of the Institut de Biologia Evolutiva in Barcelona said by email.
Taken together with all the physical and forensic evidence, historical records and folklore, it would be "extremely surprising" if the remains did not belong to the two assassinated monarchs, he added.
Read more at Discovery News
Researchers have been trying for years to verify a claim imprinted on an ornately decorated calabash that it contains a sample of the blood of the French king guillotined in Paris on January 21, 1793.
The dried, hollowed squash is adorned with portraits of revolutionary heroes and the text: "On January 21, Maximilien Bourdaloue dipped his handkerchief in the blood of Louis XVI after his decapitation".
He is then believed to have placed the fabric in the gourd, and had it embellished.
The sinister souvenir has been in the private hands of an Italian family for more than a century, said the team of experts from Spain and France which published its findings in the journal Forensic Science International.
Two years ago, analysis of DNA taken from blood traces found inside the ornate vegetable revealed a likely match for someone of Louis' description, including his blue eyes.
But not having the DNA of any kingly relation, researchers could not prove beyond doubt that the blood belonged to Louis.
Until now.
Using the genetic material, the team managed to draw a link to another gruesome artifact -- a mummified head believed to belong to Louis' 16th century predecessor, Henri IV.
In so doing, they provided evidence for authenticating both sets of remains -- uncovering a rare genetic signature shared by two men separated by seven generations.
"This study shows that (the owners of the remains) share a genetic heritage passed on through the paternal line. They have a direct link to one another through their fathers," French forensic pathologist Philippe Charlier said.
The revolution in which Louis and queen Marie-Antoinette lost their heads in public executions also saw mobs ransack the royal chapel at Saint-Denis, north of Paris -- hauling ancient monarchs like Henri from their tombs and mutilating the remains which they tossed into pits.
An individual was recorded to have rescued a severed head from the chaos.
Long thought to belong to Henri, assassinated at the age of 57 by a Catholic fanatic in 1610, the head changed hands several times over the next two centuries, bought and sold at auction or kept in secretive private collections.
Scientists in 2010 said they found proof that the head was indeed Henri's, citing physical features that matched 16th century portraits of the king, as well as radiocarbon dating, 3D scanning and X-rays.
The 2010 study, however, found no DNA and its findings have been contested by some.
With the new evidence, "it is about 250 times more likely that the (owners of the) head and the blood are paternally related, than unrelated," co-author Carles Lalueza Fox of the Institut de Biologia Evolutiva in Barcelona said by email.
Taken together with all the physical and forensic evidence, historical records and folklore, it would be "extremely surprising" if the remains did not belong to the two assassinated monarchs, he added.
Read more at Discovery News
Labels:
Archeology,
Biology,
History,
Human,
Science
Alcohol: Social Lubricant for 10,000 Years
As people ring in the New Year with dancing and a bit of bubbly, they can consider themselves part of an ancient human tradition.
Several new archaeological finds suggest that alcohol has been a social glue in parties, from work festivals to cultic feasts, since the dawn of civilization.
In the December issue of the journal Antiquity, archaeologists describe evidence of nearly 11,000-year-old beer brewing troughs at a cultic feasting site in Turkey called Göbekli Tepe. And archaeologists in Cyprus have unearthed the 3,500-year-old ruins of what may have been a primitive beer brewery and feasting hall at a site called Kissonerga-Skalia. The excavation, described in the November issue of the journal Levant, revealed several kilns that may have been used to dry malt before fermentation.
The findings suggest that alcohol has been a social lubricant for ages, said Lindy Crewe, an archaeologist at the University of Manchester, who co-authored the Levant paper.
For bread or beer?
While the cultivation of grain clearly transformed humanity, why it first happened has been hotly contested.
"This debate has been going on since the 1950's: Is the first cultivation of grain about making beer or is it about making bread?" Crewe said.
Some researchers suggest that beer arose 11,500 years ago and drove the cultivation of grains. Because grains require so much hard work to produce (collecting tiny, mostly inedible parts, separating grain from chaff, and grinding into flour), beer brewing would have been reserved for feasts with important cultural purposes.
Those feasts -- and alcohol-induced friendliness -- may have enabled hunter-gatherers to bond with larger groups of people in newly emerging villages, fueling the rise of civilization. At work parties, beer may have motivated people to put a little elbow grease into bigger-scale projects such as building ancient monuments.
"Production and consumption of alcoholic beverages is an important factor in feasts facilitating the cohesion of social groups, and in the case of Göbekli Tepe, in organizing collective work," wrote Antiquity paper co-author Oliver Dietrich in an email. Dietrich is an archaeologist for the German Archaeological Institute.
Ancient party sites
The site in Cyprus includes a courtyard and hall, along with jugs, mortars and grinding tools, and crucially, several kilns that Crewe and her colleagues believe were used to toast barley for a primitive beer. To test their hypothesis the team replicated the kilns to produce malted barley and used it in a cloudy and slightly weird-tasting beer, Crewe told LiveScience.
The Göbekli Tepe site in southwestern Turkey, meanwhile, dates to nearly 11,000 years ago. Neolithic hunter-gatherers worshipped ancient deities through dancing and feasting at the temple site, which is filled with t-shaped pillars carved with animal shapes and other ancient designs. The site also had what appears to be a primitive kitchen with large limestone troughs that held up to 42 gallons (160 liters) of liquid. The troughs held traces of oxalates, which are produced during the fermentation of grain into alcohol.
Read more at Discovery News
Several new archaeological finds suggest that alcohol has been a social glue in parties, from work festivals to cultic feasts, since the dawn of civilization.
In the December issue of the journal Antiquity, archaeologists describe evidence of nearly 11,000-year-old beer brewing troughs at a cultic feasting site in Turkey called Göbekli Tepe. And archaeologists in Cyprus have unearthed the 3,500-year-old ruins of what may have been a primitive beer brewery and feasting hall at a site called Kissonerga-Skalia. The excavation, described in the November issue of the journal Levant, revealed several kilns that may have been used to dry malt before fermentation.
The findings suggest that alcohol has been a social lubricant for ages, said Lindy Crewe, an archaeologist at the University of Manchester, who co-authored the Levant paper.
For bread or beer?
While the cultivation of grain clearly transformed humanity, why it first happened has been hotly contested.
"This debate has been going on since the 1950's: Is the first cultivation of grain about making beer or is it about making bread?" Crewe said.
Some researchers suggest that beer arose 11,500 years ago and drove the cultivation of grains. Because grains require so much hard work to produce (collecting tiny, mostly inedible parts, separating grain from chaff, and grinding into flour), beer brewing would have been reserved for feasts with important cultural purposes.
Those feasts -- and alcohol-induced friendliness -- may have enabled hunter-gatherers to bond with larger groups of people in newly emerging villages, fueling the rise of civilization. At work parties, beer may have motivated people to put a little elbow grease into bigger-scale projects such as building ancient monuments.
"Production and consumption of alcoholic beverages is an important factor in feasts facilitating the cohesion of social groups, and in the case of Göbekli Tepe, in organizing collective work," wrote Antiquity paper co-author Oliver Dietrich in an email. Dietrich is an archaeologist for the German Archaeological Institute.
Ancient party sites
The site in Cyprus includes a courtyard and hall, along with jugs, mortars and grinding tools, and crucially, several kilns that Crewe and her colleagues believe were used to toast barley for a primitive beer. To test their hypothesis the team replicated the kilns to produce malted barley and used it in a cloudy and slightly weird-tasting beer, Crewe told LiveScience.
The Göbekli Tepe site in southwestern Turkey, meanwhile, dates to nearly 11,000 years ago. Neolithic hunter-gatherers worshipped ancient deities through dancing and feasting at the temple site, which is filled with t-shaped pillars carved with animal shapes and other ancient designs. The site also had what appears to be a primitive kitchen with large limestone troughs that held up to 42 gallons (160 liters) of liquid. The troughs held traces of oxalates, which are produced during the fermentation of grain into alcohol.
Read more at Discovery News
Dec 31, 2012
Happy New Year
Just wanted to take the time and wish all you readers a very happy new year. Hope that you all will have a great new year.
From A Magical Journey
From A Magical Journey
Dec 30, 2012
Hubble Eyes the Needle Galaxy: IC 2233, One of the Flattest Galaxies Known
Like finding a silver needle in the haystack of space, the NASA/ESA Hubble Space Telescope has produced a beautiful image of the spiral galaxy IC 2233, one of the flattest galaxies known.
Typical spiral galaxies like the Milky Way are usually made up of three principal visible components: the disk where the spiral arms and most of the gas and dust is concentrated; the halo, a rough and sparse sphere around the disk that contains little gas, dust or star formation; and the central bulge at the heart of the disk, which is formed by a large concentration of ancient stars surrounding the Galactic Center.
However, IC 2233 is far from being typical. This object is a prime example of a super-thin galaxy, where the galaxy's diameter is at least ten times larger than the thickness. These galaxies consist of a simple disk of stars when seen edge on. This orientation makes them fascinating to study, giving another perspective on spiral galaxies. An important characteristic of this type of objects is that they have a low brightness and almost all of them have no bulge at all.
The bluish color that can be seen along the disk gives evidence of the spiral nature of the galaxy, indicating the presence of hot, luminous, young stars, born out of clouds of interstellar gas. In addition, unlike typical spirals, IC 2233 shows no well-defined dust lane. Only a few small patchy regions can be identified in the inner regions both above and below the galaxy's mid-plane.
Lying in the constellation of Lynx, IC 2233 is located about 40 million light-years away from Earth. This galaxy was discovered by British astronomer Isaac Roberts in 1894.
Read more at Science Daily
Typical spiral galaxies like the Milky Way are usually made up of three principal visible components: the disk where the spiral arms and most of the gas and dust is concentrated; the halo, a rough and sparse sphere around the disk that contains little gas, dust or star formation; and the central bulge at the heart of the disk, which is formed by a large concentration of ancient stars surrounding the Galactic Center.
However, IC 2233 is far from being typical. This object is a prime example of a super-thin galaxy, where the galaxy's diameter is at least ten times larger than the thickness. These galaxies consist of a simple disk of stars when seen edge on. This orientation makes them fascinating to study, giving another perspective on spiral galaxies. An important characteristic of this type of objects is that they have a low brightness and almost all of them have no bulge at all.
The bluish color that can be seen along the disk gives evidence of the spiral nature of the galaxy, indicating the presence of hot, luminous, young stars, born out of clouds of interstellar gas. In addition, unlike typical spirals, IC 2233 shows no well-defined dust lane. Only a few small patchy regions can be identified in the inner regions both above and below the galaxy's mid-plane.
Lying in the constellation of Lynx, IC 2233 is located about 40 million light-years away from Earth. This galaxy was discovered by British astronomer Isaac Roberts in 1894.
Read more at Science Daily
Scientists Challenge Current Theories About Natural Habitats and Species Diversity
How can a square meter of meadow contain tens of species of plants? And what factors determine the number of species that live in an ecosystem? Science journal has defined this as one of the 25 most important unresolved questions in science, both for its importance in understanding nature and due to the value of natural ecosystems for humankind. The value of goods and services provided by natural ecosystems is estimated to exceed the GDP of our planet.
For over 50 years, conventional ecological theories have predicted that the number of species that can coexist in a given area increases with the heterogeneity of the environmental conditions in the habitat. This premise was examined in a study conducted by research students Omri Allouche and Michael Kalyuzhny, guided by Prof. Ronen Kadmon from the Alexander Silberman Institute of Life Sciences at the Hebrew University of Jerusalem, in collaboration with Prof. Gregorio Moreno-Rueda and Prof. Manuel Pizarro from Universidad de Granada.
The researchers claim that in a heterogeneous environment -- where there are many different types of habitats -- there are fewer resources and less suitable area available to each species, making them more vulnerable to local extinction. This leads to the hypothesis that excessive habitat heterogeneity may actually reduce the number of species.
This hypothesis was examined using mathematical models and empirical analyses of natural ecosystems. Its predictions were examined with a meta-analysis of tens of datasets of plant and animal species from various localities worldwide.
Both the theoretical results and the data analyses supported the researchers' hypothesis that habitat heterogeneity may increase the rate of species extinctions and therefore reduce the number of species that inhabit the ecosystem.
These findings are very important for the conservation of biodiversity, since the current practice is to conserve areas of maximal habitat heterogeneity and even to take measures to increase habitat heterogeneity. The study shows that this conventional approach may lead to negative results, especially in the case of landscapes of limited size, which is typical of nature reserves.
Ecosystems and the species they consist of are under increasing pressure of human activity. In these conditions, skillful and intelligent management of natural landscapes is vital. This study provides scientists and policy makers with important insights for the selection and management of areas for conservation.
Read more at Science Daily
For over 50 years, conventional ecological theories have predicted that the number of species that can coexist in a given area increases with the heterogeneity of the environmental conditions in the habitat. This premise was examined in a study conducted by research students Omri Allouche and Michael Kalyuzhny, guided by Prof. Ronen Kadmon from the Alexander Silberman Institute of Life Sciences at the Hebrew University of Jerusalem, in collaboration with Prof. Gregorio Moreno-Rueda and Prof. Manuel Pizarro from Universidad de Granada.
The researchers claim that in a heterogeneous environment -- where there are many different types of habitats -- there are fewer resources and less suitable area available to each species, making them more vulnerable to local extinction. This leads to the hypothesis that excessive habitat heterogeneity may actually reduce the number of species.
This hypothesis was examined using mathematical models and empirical analyses of natural ecosystems. Its predictions were examined with a meta-analysis of tens of datasets of plant and animal species from various localities worldwide.
Both the theoretical results and the data analyses supported the researchers' hypothesis that habitat heterogeneity may increase the rate of species extinctions and therefore reduce the number of species that inhabit the ecosystem.
These findings are very important for the conservation of biodiversity, since the current practice is to conserve areas of maximal habitat heterogeneity and even to take measures to increase habitat heterogeneity. The study shows that this conventional approach may lead to negative results, especially in the case of landscapes of limited size, which is typical of nature reserves.
Ecosystems and the species they consist of are under increasing pressure of human activity. In these conditions, skillful and intelligent management of natural landscapes is vital. This study provides scientists and policy makers with important insights for the selection and management of areas for conservation.
Read more at Science Daily
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