Italian archaeologists have retrieved a sunken treasure of 3,422 ancient bronze coins in the small Sicilian island of Pantelleria, they announced today.
Discovered by chance during a survey to create an underwater archaeological itinerary,the coins have been dated between 264 and 241 BC.
At that time, Pantelleria, which lies about 70 miles southwest of Sicily, in the middle of the Sicily Strait, became a bone of contention between the Romans and Carthaginians.
Rome captured the small Mediterranean island in the First Punic War in 255 BC, but lost it a year later.
In 217 BC, in the Second Punic War, Rome finally regained the island, and even celebrated the event with commemorative coins and a holiday.
Lying at depth of about 68 feet, the coins most likely represent an episode of the Romans and Carthaginians struggle.
Amazingly, all 3,422 coins feature the same iconography.
On one side, they show Kore/Tanit, the ancient goddess of fertility, whom Carthaginians worshipped on the island around 550 BC.
On the other, the coins display the head of a horse, surrounded by symbols such as stars, letters and a caduceus. A staff often surmounted by two wings and entwined with two snakes, the caduceus was the symbol of Hermes, the messenger of the gods in Greek mythology.
Read more at Discovery News
Aug 12, 2011
Pregnant Fossil Proves Live Birth for Sea Reptile
Scientists recently got a two-for-one when they discovered the fossils of a huge fetus within the remains of a 78-million-year-old plesiosaur.
The discovery, described in the latest issue of the journal Science, represents the first known plesiosaur embryo. Plesiosaurs -- now-extinct marine reptiles -- were top sea predators while dinosaurs dominated Earth's land.
The 15.4-foot-long adult female is now the first plesiosaur for which the sex is known with certainty. The findings also provide evidence that these animals gave birth to single, live individuals instead of hatching offspring from eggs on land. Giving birth in this way indicates life was pretty good for the big, predatory reptiles.
"We speculate that this reproductive mode indicates a sedentary species living in a stable environment," co-author F. Robin O’Keefe, an associate professor in the Biology Department at Marshall University, told Discovery News.
A sometimes-sedentary lifestyle didn't prevent the animals from securing dinner, though.
"Like a lot of large apex predators, these animals would ambush or pursuit predators, basically chasing down large fish, birds, squid, ammonites, or other marine reptiles, then killing and eating them," he said. "Also, like a lot of top carnivores (particularly reptilian ones) they probably ate whatever they could catch, and would not turn up their nose at carrion either."
Other predators within their ecosystem included sharks, mosasaurs, toothed birds and pterodactyls. Plesiosaurs seldom, if ever, interacted with non-avian dinosaurs.
O'Keefe and colleague Luis Chiappe made the embryo discovery after studying the mother plesiosaur, originally unearthed in 1987 by Charles Bonner on the Bonner Ranch in Logan County, Kansas. The researchers believe at least 4 lines of evidence prove the adult plesiosaur fossils include a two-thirds mature fetus.
First, they write that the structure and attachment of the two animal remains establish the "juvenile was both articulated and within the adult body cavity at the time of deposition, before burial." It remains unclear what led to the mother's death.
Second, both sets of fossils belong to the same species, Polycotylus latippinus. Third, the juvenile skeleton displays embryonic features. And finally, "the juvenile shows no indication of having been consumed by the adult." If that'd been the case, damage caused by stomach acid, gastroliths (stomach stones), and other things would have been evident.
This particular species of plesiosaur had a unique body shape. Its neck "was short by plesiosaur standards," O’Keefe said. "All four limbs are adapted into wing-shaped flippers that the animal used to fly underwater. The tail was short and probably carried a tailfin."
The researchers suspect this plesiosaur lived in social groups and engaged in parental care, which doesn't always happen with marine predators. Great white sharks, for example, cannibalize any competing womb-mates and come into the world toothy and strong with next to zero parental care.
In humans and some other animals, attentive mothering can foster intelligence, since young have a chance to learn while being protected. Plesiosaurs, however, may have been spoiled but still rather stupid.
Read more at Discovery News
The discovery, described in the latest issue of the journal Science, represents the first known plesiosaur embryo. Plesiosaurs -- now-extinct marine reptiles -- were top sea predators while dinosaurs dominated Earth's land.
The 15.4-foot-long adult female is now the first plesiosaur for which the sex is known with certainty. The findings also provide evidence that these animals gave birth to single, live individuals instead of hatching offspring from eggs on land. Giving birth in this way indicates life was pretty good for the big, predatory reptiles.
"We speculate that this reproductive mode indicates a sedentary species living in a stable environment," co-author F. Robin O’Keefe, an associate professor in the Biology Department at Marshall University, told Discovery News.
A sometimes-sedentary lifestyle didn't prevent the animals from securing dinner, though.
"Like a lot of large apex predators, these animals would ambush or pursuit predators, basically chasing down large fish, birds, squid, ammonites, or other marine reptiles, then killing and eating them," he said. "Also, like a lot of top carnivores (particularly reptilian ones) they probably ate whatever they could catch, and would not turn up their nose at carrion either."
Other predators within their ecosystem included sharks, mosasaurs, toothed birds and pterodactyls. Plesiosaurs seldom, if ever, interacted with non-avian dinosaurs.
O'Keefe and colleague Luis Chiappe made the embryo discovery after studying the mother plesiosaur, originally unearthed in 1987 by Charles Bonner on the Bonner Ranch in Logan County, Kansas. The researchers believe at least 4 lines of evidence prove the adult plesiosaur fossils include a two-thirds mature fetus.
First, they write that the structure and attachment of the two animal remains establish the "juvenile was both articulated and within the adult body cavity at the time of deposition, before burial." It remains unclear what led to the mother's death.
Second, both sets of fossils belong to the same species, Polycotylus latippinus. Third, the juvenile skeleton displays embryonic features. And finally, "the juvenile shows no indication of having been consumed by the adult." If that'd been the case, damage caused by stomach acid, gastroliths (stomach stones), and other things would have been evident.
This particular species of plesiosaur had a unique body shape. Its neck "was short by plesiosaur standards," O’Keefe said. "All four limbs are adapted into wing-shaped flippers that the animal used to fly underwater. The tail was short and probably carried a tailfin."
The researchers suspect this plesiosaur lived in social groups and engaged in parental care, which doesn't always happen with marine predators. Great white sharks, for example, cannibalize any competing womb-mates and come into the world toothy and strong with next to zero parental care.
In humans and some other animals, attentive mothering can foster intelligence, since young have a chance to learn while being protected. Plesiosaurs, however, may have been spoiled but still rather stupid.
Read more at Discovery News
Smidgen of Antimatter Surrounds Earth
Astrophysicists studying cosmic rays have spotted "the most abundant source of antiprotons near the Earth" -- i.e., antimatter -- according to a new paper in Astrophysical Journal Letters by scientists on NASA's PAMELA project.
PAMELA stands for Payload for Antimatter Exploration and Light-nuclei Astrophysics, and the satellite-based experiment was launched in 2006 for the purpose of studying cosmic rays, high-energy subatomic particles that are slamming into the Earth's atmosphere constantly, creating showers of "daughter" particles in the process. That's right, Nature is running her very own particle accelerator experiment at the edge of Earth's atmosphere.
That means that the showers of daughter particles should include small amounts of antiprotons, just like in manmade particle accelerators. Most of those would annihilate the moment they came into contact with their ordinary matter counterparts, but astrophysicists have long hypothesized that a few remaining antiprotons could become trapped within the Earth's magnetic field, resulting in "an antiproton radiation belt" similar to the Van Allen radiation belts that already exist.
That's what PAMELA scientists think they've found, nestled within the Van Allen belts -- specifically, a region called the South Atlantic Anomaly. There's so many high energy particles trapped in this region, the Hubble Space Telescope needs to switch off whenever it passes through several times a day. So it seemed like the best place to look for elusive antiprotons.
"Trapped antiprotons can be lost in the interactions with atmospheric constituents, especially at low altitudes where the annihilation becomes the main loss mechanism," study co-author Alessandro Bruno of the University of Bari told BBC News. "Above altitudes of several hundred kilometers, the loss rate is significantly lower, allowing a large supply of antiprotons to be produced."
PAMELA scientists analyzed 850 days worth of data, focusing on those periods when the satellite was in the anomalous region. And lo and behold, they detected a small amount of antiprotons trapped in the Van Allen belts. We do mean "small": 28 antiprotons. It's still roughly three times more than one would expect to find from the solar wind, so it seems as if the hypothesis is correct.
And that, in turn, might shed light on one of the foremost mysteries in modern cosmology: what gave rise to the matter/antimatter asymmetry in the earliest moments of our universe that gave us the matter-based cosmos we know and love?
Interesting and noteworthy for physicists, sure, but is it especially exciting otherwise? I wondered, until I read the fourth sentence in the BBC News story about the paper: "The researchers say there may be enough to implement a scheme using antimatter to fuel future spacecraft."
Talk about burying your lede! But I'll go ahead and be the wet blanket here and point out that this is a pretty optimistic interpretation of "the most abundant source of antiprotons near the Earth." We're talking about exactly 28 antiprotons, here.
I get it: everyone loves Star Trek, and geeks around the world still dream of one day being able to harness the power of antimatter to fuel their very own version of the USS Enterprise, which relies on large quantities of the stuff to supply sufficient propulsion to boost the starship into its famous "warp drive."
As he did with many technical aspects of the series, for the Enterprise propulsion system, creator Gene Roddenberry drew on established scientific fact. The concept of matter/antimatter propulsion is not just the stuff of science fiction.
Read more at Discovery News
PAMELA stands for Payload for Antimatter Exploration and Light-nuclei Astrophysics, and the satellite-based experiment was launched in 2006 for the purpose of studying cosmic rays, high-energy subatomic particles that are slamming into the Earth's atmosphere constantly, creating showers of "daughter" particles in the process. That's right, Nature is running her very own particle accelerator experiment at the edge of Earth's atmosphere.
That means that the showers of daughter particles should include small amounts of antiprotons, just like in manmade particle accelerators. Most of those would annihilate the moment they came into contact with their ordinary matter counterparts, but astrophysicists have long hypothesized that a few remaining antiprotons could become trapped within the Earth's magnetic field, resulting in "an antiproton radiation belt" similar to the Van Allen radiation belts that already exist.
That's what PAMELA scientists think they've found, nestled within the Van Allen belts -- specifically, a region called the South Atlantic Anomaly. There's so many high energy particles trapped in this region, the Hubble Space Telescope needs to switch off whenever it passes through several times a day. So it seemed like the best place to look for elusive antiprotons.
"Trapped antiprotons can be lost in the interactions with atmospheric constituents, especially at low altitudes where the annihilation becomes the main loss mechanism," study co-author Alessandro Bruno of the University of Bari told BBC News. "Above altitudes of several hundred kilometers, the loss rate is significantly lower, allowing a large supply of antiprotons to be produced."
PAMELA scientists analyzed 850 days worth of data, focusing on those periods when the satellite was in the anomalous region. And lo and behold, they detected a small amount of antiprotons trapped in the Van Allen belts. We do mean "small": 28 antiprotons. It's still roughly three times more than one would expect to find from the solar wind, so it seems as if the hypothesis is correct.
And that, in turn, might shed light on one of the foremost mysteries in modern cosmology: what gave rise to the matter/antimatter asymmetry in the earliest moments of our universe that gave us the matter-based cosmos we know and love?
Interesting and noteworthy for physicists, sure, but is it especially exciting otherwise? I wondered, until I read the fourth sentence in the BBC News story about the paper: "The researchers say there may be enough to implement a scheme using antimatter to fuel future spacecraft."
Talk about burying your lede! But I'll go ahead and be the wet blanket here and point out that this is a pretty optimistic interpretation of "the most abundant source of antiprotons near the Earth." We're talking about exactly 28 antiprotons, here.
I get it: everyone loves Star Trek, and geeks around the world still dream of one day being able to harness the power of antimatter to fuel their very own version of the USS Enterprise, which relies on large quantities of the stuff to supply sufficient propulsion to boost the starship into its famous "warp drive."
As he did with many technical aspects of the series, for the Enterprise propulsion system, creator Gene Roddenberry drew on established scientific fact. The concept of matter/antimatter propulsion is not just the stuff of science fiction.
Read more at Discovery News
Aug 11, 2011
Alien World Is Blacker Than Coal
Astronomers have discovered the darkest known exoplanet -- a distant, Jupiter-sized gas giant known as TrES-2b. Their measurements show that TrES-2b reflects less than one percent of the sunlight falling on it, making it blacker than coal or any planet or moon in our solar system.
The new work appears in a paper in the journal Monthly Notices of the Royal Astronomical Society.
"TrES-2b is considerably less reflective than black acrylic paint, so it's truly an alien world," said astronomer and lead author David Kipping of the Harvard-Smithsonian Center for Astrophysics (CfA).
In our solar system, Jupiter is swathed in bright clouds of ammonia that reflect more than a third of the sunlight reaching it. In contrast, TrES-2b (which was discovered in 2006 by the Trans-Atlantic Exoplanet Survey, or TrES) lacks reflective clouds due to its high temperature.
TrES-2b orbits its star at a distance of only five million kilometres. The star's intense light heats TrES-2b to a temperature of more than 1000 degrees Celsius -- much too hot for ammonia clouds. Instead, its exotic atmosphere contains light-absorbing chemicals like vaporized sodium and potassium, or gaseous titanium oxide. Yet none of these chemicals fully explain the extreme blackness of TrES-2b.
"It's not clear what is responsible for making this planet so extraordinarily dark," stated co-author David Spiegel of Princeton University. "However, it's not completely pitch black. It's so hot that it emits a faint red glow, much like a burning ember or the coils on an electric stove."
Kipping and Spiegel determined the reflectivity of TrES-2b using data from NASA's Kepler spacecraft. Kepler is designed to measure the brightnesses of distant stars with extreme precision.
The team monitored the brightness of the TrES-2 system as the planet orbited its star. They detected a subtle dimming and brightening due to the planet's changing phase.
TrES-2b is believed to be tidally locked like our moon, so one side of the planet always faces the star. And like our moon, the planet shows changing phases as it orbits its star. This causes the total brightness of the star plus planet to vary slightly.
"By combining the impressive precision from Kepler with observations of over 50 orbits, we detected the smallest-ever change in brightness from an exoplanet: just 6 parts per million," said Kipping. "In other words, Kepler was able to directly detect visible light coming from the planet itself."
The extremely small fluctuations proved that TrES-2b is incredibly dark. A more reflective world would have shown larger brightness variations as its phase changed.
Read more at Science Daily
The new work appears in a paper in the journal Monthly Notices of the Royal Astronomical Society.
"TrES-2b is considerably less reflective than black acrylic paint, so it's truly an alien world," said astronomer and lead author David Kipping of the Harvard-Smithsonian Center for Astrophysics (CfA).
In our solar system, Jupiter is swathed in bright clouds of ammonia that reflect more than a third of the sunlight reaching it. In contrast, TrES-2b (which was discovered in 2006 by the Trans-Atlantic Exoplanet Survey, or TrES) lacks reflective clouds due to its high temperature.
TrES-2b orbits its star at a distance of only five million kilometres. The star's intense light heats TrES-2b to a temperature of more than 1000 degrees Celsius -- much too hot for ammonia clouds. Instead, its exotic atmosphere contains light-absorbing chemicals like vaporized sodium and potassium, or gaseous titanium oxide. Yet none of these chemicals fully explain the extreme blackness of TrES-2b.
"It's not clear what is responsible for making this planet so extraordinarily dark," stated co-author David Spiegel of Princeton University. "However, it's not completely pitch black. It's so hot that it emits a faint red glow, much like a burning ember or the coils on an electric stove."
Kipping and Spiegel determined the reflectivity of TrES-2b using data from NASA's Kepler spacecraft. Kepler is designed to measure the brightnesses of distant stars with extreme precision.
The team monitored the brightness of the TrES-2 system as the planet orbited its star. They detected a subtle dimming and brightening due to the planet's changing phase.
TrES-2b is believed to be tidally locked like our moon, so one side of the planet always faces the star. And like our moon, the planet shows changing phases as it orbits its star. This causes the total brightness of the star plus planet to vary slightly.
"By combining the impressive precision from Kepler with observations of over 50 orbits, we detected the smallest-ever change in brightness from an exoplanet: just 6 parts per million," said Kipping. "In other words, Kepler was able to directly detect visible light coming from the planet itself."
The extremely small fluctuations proved that TrES-2b is incredibly dark. A more reflective world would have shown larger brightness variations as its phase changed.
Read more at Science Daily
Like Humans, Chimps Are Born With Immature Forebrains
In both chimpanzees and humans, portions of the brain that are critical for complex cognitive functions, including decision-making, self-awareness and creativity, are immature at birth. But there are important differences, too. Baby chimpanzees don't show the same dramatic increase in the volume of prefrontal white matter in the brain that human infants do.
Those are the conclusions of a study reported in the August 11th Current Biology that is the first to track the development of the chimpanzee brain over time and to make the comparison to humans.
"One of the most marked evolutionary changes underlying human-specific cognitive traits is a greatly enlarged prefrontal cortex," said Tetsuro Matsuzawa of Kyoto University in Japan. "It is also one of the latest-developing brain regions of the cerebrum."
That built-in developmental delay, now shown to be shared with chimps, may provide an extended period of plasticity, allowing both humans and our closest evolutionary cousins to develop complex social interactions, knowledge and skills that are shaped by life experiences, the researchers say.
"Both humans and chimpanzees need to render their neural network and brain function more susceptible to the influence of postnatal experience," Matsuzawa said.
For instance, he added, both chimps and humans enjoy close relationships between infants and adults, as indicated by smiles and mutual gazes. On the other hand, the greater prefrontal expansion in the human brain may contribute to the development of language, complex social interaction and other abilities that are unique to us.
Matsuzawa's team made their discoveries by studying magnetic resonance imaging (MRI) scans of three growing chimpanzees from the age of six months to six years, when chimps reach pre-puberty.
The findings suggest that a less mature and more protracted elaboration of neuronal connections in the prefrontal portion of the developing brain existed in the last common ancestor of chimpanzees and humans. That commonality is in contrast to what has been observed in studies of our more distant ancestors, the macaques.
Read more at Science Daily
Those are the conclusions of a study reported in the August 11th Current Biology that is the first to track the development of the chimpanzee brain over time and to make the comparison to humans.
"One of the most marked evolutionary changes underlying human-specific cognitive traits is a greatly enlarged prefrontal cortex," said Tetsuro Matsuzawa of Kyoto University in Japan. "It is also one of the latest-developing brain regions of the cerebrum."
That built-in developmental delay, now shown to be shared with chimps, may provide an extended period of plasticity, allowing both humans and our closest evolutionary cousins to develop complex social interactions, knowledge and skills that are shaped by life experiences, the researchers say.
"Both humans and chimpanzees need to render their neural network and brain function more susceptible to the influence of postnatal experience," Matsuzawa said.
For instance, he added, both chimps and humans enjoy close relationships between infants and adults, as indicated by smiles and mutual gazes. On the other hand, the greater prefrontal expansion in the human brain may contribute to the development of language, complex social interaction and other abilities that are unique to us.
Matsuzawa's team made their discoveries by studying magnetic resonance imaging (MRI) scans of three growing chimpanzees from the age of six months to six years, when chimps reach pre-puberty.
The findings suggest that a less mature and more protracted elaboration of neuronal connections in the prefrontal portion of the developing brain existed in the last common ancestor of chimpanzees and humans. That commonality is in contrast to what has been observed in studies of our more distant ancestors, the macaques.
Read more at Science Daily
The Smithsonian Celebrates its 165th Birthday
Lucky for the bison, and perhaps also for today's tourists to Washington, D.C., the Smithsonian Institution built a zoo, along with 18 other complexes, to promote science, art and natural history and house more than 137 million artifacts – including bison. And it all began 165 years ago today, Aug. 10, 1846, when the institution got its official start.
The world's largest museum complex, the Smithsonian Institution had its humble beginnings in the heart and mind -- and ultimately, the death -- of an illegitimate son of English nobility.
James Lewis Macie, born in 1765, was the son of a Duke, Hugh Smithson, and widowed English royalty, Elizabeth Keate Hungerford Macie. After his mother's death, he took his father's surname: Smithson.
A scientist by trade and at heart, Smithson published 27 papers throughout his life -- on chemistry, geology and mineralogy -- in various scientific journals. His choice of topics included everything from the chemical compounds in a lady's teardrop to an improved method of brewing coffee. He was most famous for overturning popular scientific opinion by proving that zinc carbonates were true carbonate minerals, not zinc oxides.
But what mark his papers didn't leave on the world, his final request did. Smithson died in Italy on June 27, 1829, at the age of 64. He left all of his estate and belongings to his nephew -- with one provision that would change the course of American history. If his nephew died without any heirs, the inheritance would go to "the United States of America, to found at Washington, under the name of the Smithsonian Institution, an Establishment for the increase and diffusion of knowledge ... ."
Needless to say, Smithson's nephew left no heirs. But the United Sates didn't just inherit a sum of $508,813. It inherited a full-on political debate about accepting gifts from foreigners. Several senators made claims against the practice, afraid it would set a precedent of people being able to "purchase" their namesakes on national institutions.
President Andrew Jackson ultimately laid the groundwork for the young nation to accept the posthumous gift. But it would take several more years of legal battles in England before the money would make it back the U.S.
Read more at Discovery News
The world's largest museum complex, the Smithsonian Institution had its humble beginnings in the heart and mind -- and ultimately, the death -- of an illegitimate son of English nobility.
James Lewis Macie, born in 1765, was the son of a Duke, Hugh Smithson, and widowed English royalty, Elizabeth Keate Hungerford Macie. After his mother's death, he took his father's surname: Smithson.
A scientist by trade and at heart, Smithson published 27 papers throughout his life -- on chemistry, geology and mineralogy -- in various scientific journals. His choice of topics included everything from the chemical compounds in a lady's teardrop to an improved method of brewing coffee. He was most famous for overturning popular scientific opinion by proving that zinc carbonates were true carbonate minerals, not zinc oxides.
But what mark his papers didn't leave on the world, his final request did. Smithson died in Italy on June 27, 1829, at the age of 64. He left all of his estate and belongings to his nephew -- with one provision that would change the course of American history. If his nephew died without any heirs, the inheritance would go to "the United States of America, to found at Washington, under the name of the Smithsonian Institution, an Establishment for the increase and diffusion of knowledge ... ."
Needless to say, Smithson's nephew left no heirs. But the United Sates didn't just inherit a sum of $508,813. It inherited a full-on political debate about accepting gifts from foreigners. Several senators made claims against the practice, afraid it would set a precedent of people being able to "purchase" their namesakes on national institutions.
President Andrew Jackson ultimately laid the groundwork for the young nation to accept the posthumous gift. But it would take several more years of legal battles in England before the money would make it back the U.S.
Read more at Discovery News
Roman-Era Sword Uncovered in Ancient Ditch
A sword used by a Roman soldier during the brutal pacification of the Jews and the destruction of the Temple at Jerusalem nearly 2,000 years ago, has emerged from an ancient drainage tunnel beneath the city, Israeli authorities announced this week.
Excavated since 2007, the tunnel, which was used by Jewish rebels as a hiding place from the Romans, has also yielded a stone object adorned with a rare engraving of a menorah, the seven-branched temple candelabra that was the symbol of ancient Judaism.
The 60-centimetre (23.6-inches) long weapon, still in its leather scabbard, is the third Roman sword found in Jerusalem.
What makes the finding unique is the fine state of preservation, said the excavation directors Eli Shukron of the Israel Antiquities Authority and Ronny Reich of the University of Haifa.
"It seems that the sword belonged to an infantryman of the Roman garrison stationed in Israel at the outbreak of the Great Revolt against the Romans in 66 AD," the researchers said in a statement.
At that time, the Jewish people revolted against the tyranny of Rome, but despite a remarkable resistance, they were ultimately crushed.
The Romans also destroyed the second Temple, which, according to Jewish tradition, was built by King Herod the Great on the site of King Solomon’s temple. This was razed by the Babylonians around 587 BC.
In 70 AD, the Romans under Titus plundered tons of gold, silver trumpets and gold candelabra from Herod’s magnificent white-and-gold temple. Then they paraded the treasure, which also helped finance the building of the Colosseum, through the streets of Rome in triumph.
The moment was captured in a frieze carved into the Arch of Titus, which clearly shows the menorah, the seven-branched temple candelabra, being exposed through the streets.
Read more at Discovery News
Excavated since 2007, the tunnel, which was used by Jewish rebels as a hiding place from the Romans, has also yielded a stone object adorned with a rare engraving of a menorah, the seven-branched temple candelabra that was the symbol of ancient Judaism.
The 60-centimetre (23.6-inches) long weapon, still in its leather scabbard, is the third Roman sword found in Jerusalem.
What makes the finding unique is the fine state of preservation, said the excavation directors Eli Shukron of the Israel Antiquities Authority and Ronny Reich of the University of Haifa.
"It seems that the sword belonged to an infantryman of the Roman garrison stationed in Israel at the outbreak of the Great Revolt against the Romans in 66 AD," the researchers said in a statement.
At that time, the Jewish people revolted against the tyranny of Rome, but despite a remarkable resistance, they were ultimately crushed.
The Romans also destroyed the second Temple, which, according to Jewish tradition, was built by King Herod the Great on the site of King Solomon’s temple. This was razed by the Babylonians around 587 BC.
In 70 AD, the Romans under Titus plundered tons of gold, silver trumpets and gold candelabra from Herod’s magnificent white-and-gold temple. Then they paraded the treasure, which also helped finance the building of the Colosseum, through the streets of Rome in triumph.
The moment was captured in a frieze carved into the Arch of Titus, which clearly shows the menorah, the seven-branched temple candelabra, being exposed through the streets.
Read more at Discovery News
Aug 10, 2011
Study Builds On Plausible Scenario for Origin of Life On Earth
A relatively simple combination of naturally occurring sugars and amino acids offers a plausible route to the building blocks of life, according to a paper published in Nature Chemistry.
The study shows how the precursors to RNA could have formed on Earth before any life existed. It was authored by Jason E. Hein, Eric Tse and Donna G. Blackmond, a team of researchers with the Scripps Research Institute. Hein is now a chemistry professor with University of California, Merced.
Biological molecules, such as RNA and proteins, can exist in either a natural or unnatural form, called enantiomers. By studying the chemical reactions carefully, the research team found that it was possible to generate only the natural form of the necessary RNA precursors by including simple amino acids.
"These amino acids changed how the reactions work and allowed only the naturally occurring RNA precursors to be generated in a stable form," said Hein. "In the end, we showed that an amazingly simple result emerged from some very complex and interconnected chemistry."
The natural enantiomer of the RNA precursor molecules formed a crystal structure visible to the naked eye. The crystals are stable and avoid normal chemical breakdown. They can exist until the conditions are right for them to change into RNA.
More at Science Daily
The study shows how the precursors to RNA could have formed on Earth before any life existed. It was authored by Jason E. Hein, Eric Tse and Donna G. Blackmond, a team of researchers with the Scripps Research Institute. Hein is now a chemistry professor with University of California, Merced.
Biological molecules, such as RNA and proteins, can exist in either a natural or unnatural form, called enantiomers. By studying the chemical reactions carefully, the research team found that it was possible to generate only the natural form of the necessary RNA precursors by including simple amino acids.
"These amino acids changed how the reactions work and allowed only the naturally occurring RNA precursors to be generated in a stable form," said Hein. "In the end, we showed that an amazingly simple result emerged from some very complex and interconnected chemistry."
The natural enantiomer of the RNA precursor molecules formed a crystal structure visible to the naked eye. The crystals are stable and avoid normal chemical breakdown. They can exist until the conditions are right for them to change into RNA.
More at Science Daily
Polar Dinosaur Tracks Open New Trail to Past
Paleontologists have discovered a group of more than 20 polar dinosaur tracks on the coast of Victoria, Australia, offering a rare glimpse into animal behavior during the last period of pronounced global warming, about 105 million years ago.
The discovery, reported in the journal Alcheringa, is the largest and best collection of polar dinosaur tracks ever found in the Southern Hemisphere.
"These tracks provide us with a direct indicator of how these dinosaurs were interacting with the polar ecosystems, during an important time in geological history," says Emory paleontologist Anthony Martin, who led the research. Martin is an expert in trace fossils, which include tracks, trails, burrows, cocoons and nests.
The three-toed tracks are preserved on two sandstone blocks from the Early Cretaceous Period. They appear to belong to three different sizes of small theropods -- a group of bipedal, mostly carnivorous dinosaurs whose descendants include modern birds. Photos of the tracks, above and below, by Anthony Martin.
The research team also included Thomas Rich, from the Museum Victoria; Michael Hall and Patricia Vickers-Rich, both from the School of Geosciences at Monash University in Victoria; and Gonzalo Vazquez-Prokopec, an ecologist and expert in spatial analysis from Emory's Department of Environmental Studies.
The tracks were found on the rocky shoreline of remote Milanesia Beach, in Otways National Park. This area, west of Melbourne, is known for energetic surf and rugged coastal cliffs, consisting of layers of sediment accumulated over millions of years. Riddled with fractures and pounded by waves and wind, the cliffs occasionally shed large chunks of rock, such as those containing the dinosaur tracks.
One sandstone block has about 15 tracks, including three consecutive footprints made by the smallest of the theropods, estimated to be the size of a chicken. Martin spotted this first known dinosaur trackway of Victoria last June 14, around noon. He was on the lookout, since he had earlier noticed ripple marks and trace fossils of what looked like insect burrows in piles of fallen rock.
"The ripples and burrows indicate a floodplain, which is the most likely area to find polar dinosaur tracks," Martin explains. The second block containing tracks was spotted about three hours later by Greg Denney, a local volunteer who accompanied Martin and Rich on that day's expedition. That block had similar characteristics to the first one, and included eight tracks. The tracks show what appear to be theropods ranging in size from a chicken to a large crane.
"We believe that the two blocks were from the same rock layer, and the same surface, that the dinosaurs were walking on," Martin says.
The small, medium and large tracks may have been made by three different species, Martin says. "They could also belong to two genders and a juvenile of one species -- a little dinosaur family -- but that's purely speculative," he adds.
The Victoria Coast marks the seam where Australia was once joined to Antarctica. During that era, about 115-105 million years ago, the dinosaurs roamed in prolonged polar darkness. Earth's average temperature was 68 degrees Fahrenheit -- just 10 degrees warmer than today -- and the spring thaws would cause torrential flooding in the river valleys.
The dinosaur tracks were probably made during the summer, Martin says. "The ground would have been frozen in the winter, and in order for the waters to subside so that animals could walk across the floodplain, it would have to be later in the season," he explains.
More at Science Daily
The discovery, reported in the journal Alcheringa, is the largest and best collection of polar dinosaur tracks ever found in the Southern Hemisphere.
"These tracks provide us with a direct indicator of how these dinosaurs were interacting with the polar ecosystems, during an important time in geological history," says Emory paleontologist Anthony Martin, who led the research. Martin is an expert in trace fossils, which include tracks, trails, burrows, cocoons and nests.
The three-toed tracks are preserved on two sandstone blocks from the Early Cretaceous Period. They appear to belong to three different sizes of small theropods -- a group of bipedal, mostly carnivorous dinosaurs whose descendants include modern birds. Photos of the tracks, above and below, by Anthony Martin.
The research team also included Thomas Rich, from the Museum Victoria; Michael Hall and Patricia Vickers-Rich, both from the School of Geosciences at Monash University in Victoria; and Gonzalo Vazquez-Prokopec, an ecologist and expert in spatial analysis from Emory's Department of Environmental Studies.
The tracks were found on the rocky shoreline of remote Milanesia Beach, in Otways National Park. This area, west of Melbourne, is known for energetic surf and rugged coastal cliffs, consisting of layers of sediment accumulated over millions of years. Riddled with fractures and pounded by waves and wind, the cliffs occasionally shed large chunks of rock, such as those containing the dinosaur tracks.
One sandstone block has about 15 tracks, including three consecutive footprints made by the smallest of the theropods, estimated to be the size of a chicken. Martin spotted this first known dinosaur trackway of Victoria last June 14, around noon. He was on the lookout, since he had earlier noticed ripple marks and trace fossils of what looked like insect burrows in piles of fallen rock.
"The ripples and burrows indicate a floodplain, which is the most likely area to find polar dinosaur tracks," Martin explains. The second block containing tracks was spotted about three hours later by Greg Denney, a local volunteer who accompanied Martin and Rich on that day's expedition. That block had similar characteristics to the first one, and included eight tracks. The tracks show what appear to be theropods ranging in size from a chicken to a large crane.
"We believe that the two blocks were from the same rock layer, and the same surface, that the dinosaurs were walking on," Martin says.
The small, medium and large tracks may have been made by three different species, Martin says. "They could also belong to two genders and a juvenile of one species -- a little dinosaur family -- but that's purely speculative," he adds.
The Victoria Coast marks the seam where Australia was once joined to Antarctica. During that era, about 115-105 million years ago, the dinosaurs roamed in prolonged polar darkness. Earth's average temperature was 68 degrees Fahrenheit -- just 10 degrees warmer than today -- and the spring thaws would cause torrential flooding in the river valleys.
The dinosaur tracks were probably made during the summer, Martin says. "The ground would have been frozen in the winter, and in order for the waters to subside so that animals could walk across the floodplain, it would have to be later in the season," he explains.
More at Science Daily
Enormous Bird Lived Alongside Dinosaurs
An enormous prehistoric bird, which might have resembled a very big ostrich, lived alongside dinosaurs around 83 million years ago, according to new research.
The bird, called Samrukia nessovi after the mythical Kazakh Phoenix, lived in what is now Kazakhstan. It is described in the latest Royal Society Biology Letters.
The discovery confirms "that big birds were living alongside Cretaceous non-avian dinosaurs," lead author Darren Naish said. "In fact, these big birds fit into the idea that the Cretaceous wasn't 'a non-avian dinosaurs-only theme park.' Sure, non-avian dinosaurs were important and big in ecological terms, but there was at least some space for other land animals."
Naish is an honorary research associate in the School of Earth & Environmental Sciences at the University of Portsmouth. He and his team made the discovery after analyzing the fossil for Samrukia, which previously had been modified by someone to resemble an oviraptorosaur (a type of feathered dinosaur).
All that's left of this big bird is its toothless lower jaw. The structure and characteristics of the jaw are associated with birds and not non-avian dinosaurs, the researchers believe.
They conclude that the skull of the bird during its lifetime would have been about a foot long. If flightless, it could have stood close to 10 feet tall. If it flew, its wingspan is likely to have exceeded 13 feet.
The big bird is now the second known large avian from the dinosaur era. The first to be identified was Gargantuavis philoinos, which lived in southern France around 70 million years ago. It too may have been flightless and ostrich-like.
"So we can now be really confident that Mesozoic terrestrial birds weren't all thrush-sized or crow-sized animals," Naish said. "Giant size definitely evolved in these animals, and giant forms were living in at least two distinct regions. This fits into a larger, emerging picture: Mesozoic birds were ecologically diverse, with lots of overlap between them and modern groups."
During its day, Samrukia existed in an ecosystem that included armored dinosaurs, duckbilled dinosaurs, and tyrannosaurs -- along with other predatory dinos. Smaller birds are also known from this site, called the Bostobynskaya Formation. Sharks, turtles and salamanders from the bird's time period have also been found in the region.
At present, the site is dry and hot. It's dominated by semi-desert or scrub. Back in the dinosaur era, it was more of a floodplain environment, with a flat plain crisscrossed by big, meandering rivers. Fossil wood suggests forests were nearby.
It remains unclear what the big bird hunted, but the researchers could not find any evidence for obvious specialization, such as dedication to plant consumption or aquatic prey. They therefore suspect it was a generalist, per many modern birds today.
The bird probably also spent a lot of time running or flying away from the numerous meat-eating dinosaurs from the area.
Such distinctions were obviously important to the animals at the time, but paleontologists now must tease apart birds from non-avian dinosaurs. In the case of this latest discovery, a fossil attributed to a dinosaur was determined to be a bird. Recently, however, the supposed "world's oldest known bird," Archaeopteryx, was found to be a non-avian dinosaur. Naish and his team agree with that assessment.
Read more at Discovery News
The bird, called Samrukia nessovi after the mythical Kazakh Phoenix, lived in what is now Kazakhstan. It is described in the latest Royal Society Biology Letters.
The discovery confirms "that big birds were living alongside Cretaceous non-avian dinosaurs," lead author Darren Naish said. "In fact, these big birds fit into the idea that the Cretaceous wasn't 'a non-avian dinosaurs-only theme park.' Sure, non-avian dinosaurs were important and big in ecological terms, but there was at least some space for other land animals."
Naish is an honorary research associate in the School of Earth & Environmental Sciences at the University of Portsmouth. He and his team made the discovery after analyzing the fossil for Samrukia, which previously had been modified by someone to resemble an oviraptorosaur (a type of feathered dinosaur).
All that's left of this big bird is its toothless lower jaw. The structure and characteristics of the jaw are associated with birds and not non-avian dinosaurs, the researchers believe.
They conclude that the skull of the bird during its lifetime would have been about a foot long. If flightless, it could have stood close to 10 feet tall. If it flew, its wingspan is likely to have exceeded 13 feet.
The big bird is now the second known large avian from the dinosaur era. The first to be identified was Gargantuavis philoinos, which lived in southern France around 70 million years ago. It too may have been flightless and ostrich-like.
"So we can now be really confident that Mesozoic terrestrial birds weren't all thrush-sized or crow-sized animals," Naish said. "Giant size definitely evolved in these animals, and giant forms were living in at least two distinct regions. This fits into a larger, emerging picture: Mesozoic birds were ecologically diverse, with lots of overlap between them and modern groups."
During its day, Samrukia existed in an ecosystem that included armored dinosaurs, duckbilled dinosaurs, and tyrannosaurs -- along with other predatory dinos. Smaller birds are also known from this site, called the Bostobynskaya Formation. Sharks, turtles and salamanders from the bird's time period have also been found in the region.
At present, the site is dry and hot. It's dominated by semi-desert or scrub. Back in the dinosaur era, it was more of a floodplain environment, with a flat plain crisscrossed by big, meandering rivers. Fossil wood suggests forests were nearby.
It remains unclear what the big bird hunted, but the researchers could not find any evidence for obvious specialization, such as dedication to plant consumption or aquatic prey. They therefore suspect it was a generalist, per many modern birds today.
The bird probably also spent a lot of time running or flying away from the numerous meat-eating dinosaurs from the area.
Such distinctions were obviously important to the animals at the time, but paleontologists now must tease apart birds from non-avian dinosaurs. In the case of this latest discovery, a fossil attributed to a dinosaur was determined to be a bird. Recently, however, the supposed "world's oldest known bird," Archaeopteryx, was found to be a non-avian dinosaur. Naish and his team agree with that assessment.
Read more at Discovery News
Aug 9, 2011
Chimpanzees Not as Selfish as We Thought
Humans aren't the only altruistic primates. New research demonstrates chimpanzees also show unselfish concern for the welfare of others.
The study, published in the latest Proceedings of the National Academy of Sciences, negates prior findings that concluded chimpanzees are "indifferent to the welfare" of their fellow chimps.
Insects and many other creatures help each other out, but it's believed that primate altruism is empathy-based, with this trait being widespread among mammals.
"Since empathy is an old mammalian trait, there is no reason why the sort of altruism we describe should be unique for the primates," co-author Frans de Waal, director of the Living Links Center at the Yerkes Primate Center, told Discovery News.
"I expect it will be found in dogs (and) rats," he added. "We, and others, found it previously in monkeys: capuchin monkeys, marmosets, tamarins."
For this latest study, de Waal and colleagues Victoria Horner, J. Devyn Carter and Malini Suchak presented 7 female chimps with a bucket containing 30 tokens. The scientists chose to look at all females to avoid potential sex-based conflicts.
For each experiment, the tokens came in two different colors. Choosing tokens of a certain color would result in a "selfish outcome," which was a food reward for just the participant. Choosing tokens of the other color resulted in food rewards for both the token selector and another nearby chimp in an adjacent compartment.
The food rewards consisted of banana slices wrapped in butcher paper that made a loud sound when unwrapped.
The chimp participants nearly always chose the tokens that would yield food rewards for both the selector and the nearby observing chimp. They would do this with or without solicitation from the chimp bystander, who could smell the bananas and hear the tantalizing paper unwrapping. At times the bystanders begged, whined and even spit water. Such behavior didn’t help their cause much, contradicting prior suggestions that chimps only share when under social pressure.
The researchers believe earlier studies confused chimp participants, since the experiments involved rather complex apparatuses. These earlier studies, according to lead author Horner and her team, also promoted competition, caused the chimps to become preoccupied with visible reward options, and permitted little communication among the chimps. In this study, “extensive communication” between the participants took place.
Christophe Boesch, director of the Department of Primatology at the Max Planck Institute for Evolutionary Anthropology, told Discovery News, "All studies with wild chimpanzees have amply documented that they share meat and other food abundantly, that they help one another in highly risky situations, like when facing predators or neighboring communities, and adopt needing orphans."
Given this information, both he and de Waal expressed frustration over the earlier research that concluded chimpanzees were essentially selfish animals.
More at Discovery News
The study, published in the latest Proceedings of the National Academy of Sciences, negates prior findings that concluded chimpanzees are "indifferent to the welfare" of their fellow chimps.
Insects and many other creatures help each other out, but it's believed that primate altruism is empathy-based, with this trait being widespread among mammals.
"Since empathy is an old mammalian trait, there is no reason why the sort of altruism we describe should be unique for the primates," co-author Frans de Waal, director of the Living Links Center at the Yerkes Primate Center, told Discovery News.
"I expect it will be found in dogs (and) rats," he added. "We, and others, found it previously in monkeys: capuchin monkeys, marmosets, tamarins."
For this latest study, de Waal and colleagues Victoria Horner, J. Devyn Carter and Malini Suchak presented 7 female chimps with a bucket containing 30 tokens. The scientists chose to look at all females to avoid potential sex-based conflicts.
For each experiment, the tokens came in two different colors. Choosing tokens of a certain color would result in a "selfish outcome," which was a food reward for just the participant. Choosing tokens of the other color resulted in food rewards for both the token selector and another nearby chimp in an adjacent compartment.
The food rewards consisted of banana slices wrapped in butcher paper that made a loud sound when unwrapped.
The chimp participants nearly always chose the tokens that would yield food rewards for both the selector and the nearby observing chimp. They would do this with or without solicitation from the chimp bystander, who could smell the bananas and hear the tantalizing paper unwrapping. At times the bystanders begged, whined and even spit water. Such behavior didn’t help their cause much, contradicting prior suggestions that chimps only share when under social pressure.
The researchers believe earlier studies confused chimp participants, since the experiments involved rather complex apparatuses. These earlier studies, according to lead author Horner and her team, also promoted competition, caused the chimps to become preoccupied with visible reward options, and permitted little communication among the chimps. In this study, “extensive communication” between the participants took place.
Christophe Boesch, director of the Department of Primatology at the Max Planck Institute for Evolutionary Anthropology, told Discovery News, "All studies with wild chimpanzees have amply documented that they share meat and other food abundantly, that they help one another in highly risky situations, like when facing predators or neighboring communities, and adopt needing orphans."
Given this information, both he and de Waal expressed frustration over the earlier research that concluded chimpanzees were essentially selfish animals.
More at Discovery News
Why Some People Don't Develop Fingerprints
A fingerprint can identify you at birth, death and any time in between. But some people don't develop unique dermal ridges on their fingers, and thus, do not have fingerprints.
In the womb, a fetus begins to form fingerprints after 24 weeks. These patterns, called dermatoglyphs, remain the same throughout most people's lives. But researchers suspect a mutation in one gene allows some people to skip the process of forming fingerprints during development. The rare result: adermatoglyphia, or the condition of not having fingerprints.
After looking at 16 related individuals, scientists reported a mutation in a version of the SMARCAD1 gene region associated with people who lacked fingerprints. They also found adermatoglyphia to be autosomal dominant, meaning only one parent needs to pass on the mutation for the child to show it.
As you can imagine, not having fingerprints can present challenges in countries that regularly use them for identification and travel. In fact, the condition was informally called "immigration delay disease" because of its tendency to limit travel. Interestingly, the team of researchers decided to study one Swiss woman with the condition -- and her family -- after she had issues entering the United States because she had no fingerprints to scan, according to one ScienceNOW article.
Read more at Discovery News
In the womb, a fetus begins to form fingerprints after 24 weeks. These patterns, called dermatoglyphs, remain the same throughout most people's lives. But researchers suspect a mutation in one gene allows some people to skip the process of forming fingerprints during development. The rare result: adermatoglyphia, or the condition of not having fingerprints.
After looking at 16 related individuals, scientists reported a mutation in a version of the SMARCAD1 gene region associated with people who lacked fingerprints. They also found adermatoglyphia to be autosomal dominant, meaning only one parent needs to pass on the mutation for the child to show it.
As you can imagine, not having fingerprints can present challenges in countries that regularly use them for identification and travel. In fact, the condition was informally called "immigration delay disease" because of its tendency to limit travel. Interestingly, the team of researchers decided to study one Swiss woman with the condition -- and her family -- after she had issues entering the United States because she had no fingerprints to scan, according to one ScienceNOW article.
Read more at Discovery News
Mystery Minnesota Monster Sparks Speculation
A strange animal found on a Douglas County, Minnesota, road has people talking monsters.
The Star Tribune offered this description of the animal that Lacey Ilse found alongside a road in Alexandria: “ghostly white and hairless, its neck bloated out of proportion with the rest of its limp body.” Ilse said it looked “half human,” and told her friends about it.
Soon photos of the little beastie flew around the Internet and became a minor Facebook sensation. The Montreal Gazette claimed a few days ago that “scientists are baffled,” though the public has been happy to offer their theories.
Speculations about what the creature may be include a dog, a badger, a wolf, raccoon, and even a top-secret government experiment. Predictably, some suggested that the monster is instead the chupacabra, the Hispanic vampire beast. In fact the animal looks nothing like the original chupacabra (which was revealed earlier this year to have come from a science fiction film), nor does it resemble the “chupacabras” found mainly in Texas that have been shown through DNA analysis to be dogs and coyotes. Furthermore, it was not seen (nor even suspected of) sucking blood.
So what is it?
Biologists have several ways of identifying animals. One of the best is through simply comparing the animal's weight, size, and other characteristics to those of known animals. There’s an even more specialized field of study called taphonomy that deals specifically with dead and decaying animals. Since many animals are found in early states of decomposition, it's important to understand what happens to creatures after they die. For example, hair falls out, tissue shrinks away from teeth and nails, and so on; all these can contribute to a mysterious or otherworldly appearance.
Then, of course, there's genetic analysis. This is considered by many to be the gold standard, though in some cases those who have found mysterious animals have refused to accept the results of DNA testing.
A close analysis of photographs and video of the creature give some important clues to its identity. For one thing, its length and size is well within the normal range for a badger. It has five toes, each ending with long nails. Canine (for example, dog, coyote, or fox) nails are not usually that long, and Minnesota wildlife expert Kevin Kotts said that "It's got five long front claws on each of its front feet, which would be characteristic of a badger.”
Why would it be “ghostly white and hairless”? Because it's been dead a while and the blood has pooled or coagulated, and most of the hair has fallen out from decay. Why would the back part look so misshapen, as several people noticed? Probably because it had been run over by a car or truck, having been found in the middle of the road.
There's another, less obvious reason to believe that the beast is merely a common animal instead of a new creature or unknown monster: only one of them has been found. For the same reason that there must be thousands, or tens of thousands, of Bigfoot in North America to maintain a sufficiently large breeding population, there should be thousands of these critters around if they are a new species.
Read more at Discovery News
The Star Tribune offered this description of the animal that Lacey Ilse found alongside a road in Alexandria: “ghostly white and hairless, its neck bloated out of proportion with the rest of its limp body.” Ilse said it looked “half human,” and told her friends about it.
Soon photos of the little beastie flew around the Internet and became a minor Facebook sensation. The Montreal Gazette claimed a few days ago that “scientists are baffled,” though the public has been happy to offer their theories.
Speculations about what the creature may be include a dog, a badger, a wolf, raccoon, and even a top-secret government experiment. Predictably, some suggested that the monster is instead the chupacabra, the Hispanic vampire beast. In fact the animal looks nothing like the original chupacabra (which was revealed earlier this year to have come from a science fiction film), nor does it resemble the “chupacabras” found mainly in Texas that have been shown through DNA analysis to be dogs and coyotes. Furthermore, it was not seen (nor even suspected of) sucking blood.
So what is it?
Biologists have several ways of identifying animals. One of the best is through simply comparing the animal's weight, size, and other characteristics to those of known animals. There’s an even more specialized field of study called taphonomy that deals specifically with dead and decaying animals. Since many animals are found in early states of decomposition, it's important to understand what happens to creatures after they die. For example, hair falls out, tissue shrinks away from teeth and nails, and so on; all these can contribute to a mysterious or otherworldly appearance.
Then, of course, there's genetic analysis. This is considered by many to be the gold standard, though in some cases those who have found mysterious animals have refused to accept the results of DNA testing.
A close analysis of photographs and video of the creature give some important clues to its identity. For one thing, its length and size is well within the normal range for a badger. It has five toes, each ending with long nails. Canine (for example, dog, coyote, or fox) nails are not usually that long, and Minnesota wildlife expert Kevin Kotts said that "It's got five long front claws on each of its front feet, which would be characteristic of a badger.”
Why would it be “ghostly white and hairless”? Because it's been dead a while and the blood has pooled or coagulated, and most of the hair has fallen out from decay. Why would the back part look so misshapen, as several people noticed? Probably because it had been run over by a car or truck, having been found in the middle of the road.
There's another, less obvious reason to believe that the beast is merely a common animal instead of a new creature or unknown monster: only one of them has been found. For the same reason that there must be thousands, or tens of thousands, of Bigfoot in North America to maintain a sufficiently large breeding population, there should be thousands of these critters around if they are a new species.
Read more at Discovery News
Meteorites Carried Life's Building Block to Earth
A new analysis of carbon meteorites suggests that they likely carried some of the building blocks needed for DNA to the Earth, according to a NASA-funded study.
The research in the Proceedings of the National Academy of Sciences adds weight to the long-debated theory that at least some of the materials needed to make early life forms came to our planet via meteorites.
Scientists used advanced mass spectrometry instruments to scan 11 organic-rich meteorites called carbonaceous chondrites for nucleobases, which contribute to making DNA and RNA.
They found three nucleobases -- purine, 6,8-diaminopurine and 2,6-diaminopurine -- that "are widely distributed in carbonaceous chondrites" and which are "rare or absent in terrestrial biology," said the study.
Scientists found no significant concentrations of the trio in soil and ice samples near where the meteorites landed, the study said.
"Finding nucleobase compounds not typically found in Earth's biochemistry strongly supports an extraterrestrial origin," said Jim Cleaves, one of the study's authors from the Carnegie Institute of Washington's Geophysical Laboratory.
"This shows us that meteorites may have been molecular tool kits, which provided the essential building blocks for life on Earth," Cleaves said.
More at Discovery News
The research in the Proceedings of the National Academy of Sciences adds weight to the long-debated theory that at least some of the materials needed to make early life forms came to our planet via meteorites.
Scientists used advanced mass spectrometry instruments to scan 11 organic-rich meteorites called carbonaceous chondrites for nucleobases, which contribute to making DNA and RNA.
They found three nucleobases -- purine, 6,8-diaminopurine and 2,6-diaminopurine -- that "are widely distributed in carbonaceous chondrites" and which are "rare or absent in terrestrial biology," said the study.
Scientists found no significant concentrations of the trio in soil and ice samples near where the meteorites landed, the study said.
"Finding nucleobase compounds not typically found in Earth's biochemistry strongly supports an extraterrestrial origin," said Jim Cleaves, one of the study's authors from the Carnegie Institute of Washington's Geophysical Laboratory.
"This shows us that meteorites may have been molecular tool kits, which provided the essential building blocks for life on Earth," Cleaves said.
More at Discovery News
Aug 8, 2011
Did Past Climate Change Encourage Tree-Killing Fungi?
The demise of the world's forests some 250 million years ago likely was accelerated by aggressive tree-killing fungi triggered by global climate change, according to a new study by a University of California, Berkeley, scientist and her Dutch and British colleagues.
The researchers do not rule out the possibility that today's changing climate could cause a similar increase in pathogenic soil bacteria that could devastate forests already stressed by a warming climate and pollution.
The study, available online Aug. 5, will be published in the September 2011 print edition of the journal Geology of the Geological Society of America.
The death of the forests -- primarily composed of conifers, which are distant relatives of today's pines and firs -- was part of the largest extinction of life on Earth, which occurred when today's continents were part of one supercontinent, Pangaea. The so-called Permian extinction likely was triggered by immense volcanic eruptions in what is now Siberia. The huge amounts of gas and dust thrown into the atmosphere altered global climate, and some 95 percent of marine organisms and 70 percent of land organisms eventually went extinct.
The scientists claim that thread-like or filamentous microfossils commonly preserved in Permian rock are relatives of a group of fungi, Rhizoctonia, that today is known for members that attack and kill plants.
"Modern Rhizoctonia include some of the most ubiquitous plant pathogens, causing root, stem and foliar diseases in a wide variety of plants," said coauthor Cindy Looy, UC Berkeley assistant professor of integrative biology. "Based on patterns of present-day forest decline, it is likely that fungal disease has been an essential accessory in woodland destabilization, accelerating widespread tree mortality during the end-Permian crisis."
The conifer forests, which covered the semi-arid equatorial region of Pangaea, were eventually replaced by lycopods -- four foot-tall relatives of today's diminutive club mosses -- as well as by seed ferns (pteridosperms). The conifers didn't recover for another 4 to 5 million years.
Looy and her colleagues -- Henk Visscher of the Laboratory of Palaeobotany and Palynology at Utrecht University in the Netherlands and Mark Sephton of the Impacts and Astromaterials Research Centre at Imperial College, London -- caution that today's changing climate could also lead to increased activity of pathogenic soil microbes that could accelerate the death of trees already stressed by higher temperatures and drought.
"Pathogenic fungi are important elements of all forest ecosystems," said Visscher. "When an entire forest becomes weakened by environmental stress factors, onslaught of damaging fungal diseases can result in large-scale tissue death and tree mortality."
The researchers dispute the conclusion of other researchers who claim that the thread-like microfossils are the remains of algae. Furthermore, while the researchers previously thought that Reduviasporonites were fungi that took advantage of dying forests, they now believe the fungi actively helped destroy the forests.
"Previously, mass occurrences of Reduviasporonites had been ascribed to wood-rotting fungi living off an excessive abundance of dead wood," said Looy, a paleobotanist who focuses on pollen and spores as keys to understanding past plant communities. "However, the notion that the microfossils represent Rhizoctonia-like resting structures suggest a much more active role for fungi in the ecological crisis:"
The researchers' conclusion comes largely from the fact that they have found living fungi in the genus Rhizoctonia that have a dormant or resting stage during their life cycles in which they look nearly identical to Reduviasporonites.
Read more at Science Daily
The researchers do not rule out the possibility that today's changing climate could cause a similar increase in pathogenic soil bacteria that could devastate forests already stressed by a warming climate and pollution.
The study, available online Aug. 5, will be published in the September 2011 print edition of the journal Geology of the Geological Society of America.
The death of the forests -- primarily composed of conifers, which are distant relatives of today's pines and firs -- was part of the largest extinction of life on Earth, which occurred when today's continents were part of one supercontinent, Pangaea. The so-called Permian extinction likely was triggered by immense volcanic eruptions in what is now Siberia. The huge amounts of gas and dust thrown into the atmosphere altered global climate, and some 95 percent of marine organisms and 70 percent of land organisms eventually went extinct.
The scientists claim that thread-like or filamentous microfossils commonly preserved in Permian rock are relatives of a group of fungi, Rhizoctonia, that today is known for members that attack and kill plants.
"Modern Rhizoctonia include some of the most ubiquitous plant pathogens, causing root, stem and foliar diseases in a wide variety of plants," said coauthor Cindy Looy, UC Berkeley assistant professor of integrative biology. "Based on patterns of present-day forest decline, it is likely that fungal disease has been an essential accessory in woodland destabilization, accelerating widespread tree mortality during the end-Permian crisis."
The conifer forests, which covered the semi-arid equatorial region of Pangaea, were eventually replaced by lycopods -- four foot-tall relatives of today's diminutive club mosses -- as well as by seed ferns (pteridosperms). The conifers didn't recover for another 4 to 5 million years.
Looy and her colleagues -- Henk Visscher of the Laboratory of Palaeobotany and Palynology at Utrecht University in the Netherlands and Mark Sephton of the Impacts and Astromaterials Research Centre at Imperial College, London -- caution that today's changing climate could also lead to increased activity of pathogenic soil microbes that could accelerate the death of trees already stressed by higher temperatures and drought.
"Pathogenic fungi are important elements of all forest ecosystems," said Visscher. "When an entire forest becomes weakened by environmental stress factors, onslaught of damaging fungal diseases can result in large-scale tissue death and tree mortality."
The researchers dispute the conclusion of other researchers who claim that the thread-like microfossils are the remains of algae. Furthermore, while the researchers previously thought that Reduviasporonites were fungi that took advantage of dying forests, they now believe the fungi actively helped destroy the forests.
"Previously, mass occurrences of Reduviasporonites had been ascribed to wood-rotting fungi living off an excessive abundance of dead wood," said Looy, a paleobotanist who focuses on pollen and spores as keys to understanding past plant communities. "However, the notion that the microfossils represent Rhizoctonia-like resting structures suggest a much more active role for fungi in the ecological crisis:"
The researchers' conclusion comes largely from the fact that they have found living fungi in the genus Rhizoctonia that have a dormant or resting stage during their life cycles in which they look nearly identical to Reduviasporonites.
Read more at Science Daily
Brain's Map of Space Falls Flat When It Comes to Altitude
Animal's brains are only roughly aware of how high-up they are in space, meaning that in terms of altitude the brain's 'map' of space is surprisingly flat, according to new research.
In a study published online August 7 in Nature Neuroscience, scientists studied cells in or near a part of the brain called the hippocampus, which forms the brain's map of space, to see whether they were activated when rats climbed upwards.
The study, supported by the Wellcome Trust, looked at two types of cells known to be involved in the brain's representation of space: grid cells, which measure distance, and place cells, which indicate location. Scientists found that only place cells were sensitive to the animal moving upwards in altitude, and even then only weakly so.
Professor Kate Jeffery, lead author from UCL Psychology and Language Sciences, said: "The implication is that our internal sense of space is actually rather flat -- we are very sensitive to where we are in horizontal space but only vaguely aware of how high we are.
"This finding is surprising and it has implications for situations in which people have to move freely in all three dimensions -- divers, pilots and astronauts for example. It also raises the question -- if our map of space is flat, then how do we navigate through complex environments so effectively?"
How the hippocampus makes its map of space is fairly well understood for flat environments, but the world is of course not flat -- it has a richly varied topography, and a useful map therefore needs to work in all three dimensions. However, adding a third dimension to the two horizontal ones makes things very much more complicated for a map, and it is not clear how -- or even if -- the brain can encode this.
To begin to answer this question scientists looked at neurons known as grid cells, which become active periodically and at very regular distances as animals walk around, forming a grid-like structure of activity hot-spots. Previous work has found that grid cells are largely concerned with marking out distances.
In the study, rats walked not just on flat ground but also on pegs on a climbing wall, or else on a spiral staircase, so that the rats moved not only horizontally but also vertically. Interestingly, the grid cells still kept track of horizontal distance but did not measure out vertical distances. It seems as if grid cells do not "know" how high they are.
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In a study published online August 7 in Nature Neuroscience, scientists studied cells in or near a part of the brain called the hippocampus, which forms the brain's map of space, to see whether they were activated when rats climbed upwards.
The study, supported by the Wellcome Trust, looked at two types of cells known to be involved in the brain's representation of space: grid cells, which measure distance, and place cells, which indicate location. Scientists found that only place cells were sensitive to the animal moving upwards in altitude, and even then only weakly so.
Professor Kate Jeffery, lead author from UCL Psychology and Language Sciences, said: "The implication is that our internal sense of space is actually rather flat -- we are very sensitive to where we are in horizontal space but only vaguely aware of how high we are.
"This finding is surprising and it has implications for situations in which people have to move freely in all three dimensions -- divers, pilots and astronauts for example. It also raises the question -- if our map of space is flat, then how do we navigate through complex environments so effectively?"
How the hippocampus makes its map of space is fairly well understood for flat environments, but the world is of course not flat -- it has a richly varied topography, and a useful map therefore needs to work in all three dimensions. However, adding a third dimension to the two horizontal ones makes things very much more complicated for a map, and it is not clear how -- or even if -- the brain can encode this.
To begin to answer this question scientists looked at neurons known as grid cells, which become active periodically and at very regular distances as animals walk around, forming a grid-like structure of activity hot-spots. Previous work has found that grid cells are largely concerned with marking out distances.
In the study, rats walked not just on flat ground but also on pegs on a climbing wall, or else on a spiral staircase, so that the rats moved not only horizontally but also vertically. Interestingly, the grid cells still kept track of horizontal distance but did not measure out vertical distances. It seems as if grid cells do not "know" how high they are.
More at Science Daily
Earth May Not Have Needed Moon for Life
Scientists have long believed that without the moon's stabilizing gravitational influence, variations in Earth's tilt would have caused climate change too dynamic for complex life to evolve. Not so, concludes a new study that has implications for understanding conditions for life elsewhere in the solar system.
The study sprang from the ongoing Kepler Telescope mission to find Earth-like planets circling in habitable zones around other stars in the Milky Way.
"We were wondering 'Do we really have to find a moon or not?' around potentially habitable worlds, planetary scientist Jason Barnes, with the University of Idaho, told Discovery News.
Previous studies showed that without the steadying gravitational influence of a large moon, Earth's tilt would shift by as much as about 85 degrees every 100,000 years or so, alternatively freezing and baking the planet's poles. Scientists believe a stable climate spanning about 500,000 years was necessary for complex life to blossom on Earth.
A new computational analysis, however, shows that a moonless Earth would still have swings in its tilt but the influence of Jupiter and other factors would limit the variations to about 10 degrees in either direction.
Earth's rotational tilt varies between 0.5 and 1 degree about every 100,000 years.
"Plus- or minus-10 would certainly be noticeable and may be a problem, but I don't think it would prevent life from coming about," Barnes said.
"It's a very intriguing result. It's provocative," Richard Vondrak, lead scientist with NASA's ongoing Lunar Reconnaissance Orbiter mission, told Discovery News.
"On the moon we can find important evidence and clues of what happened to not only to the moon, but also to the Earth-moon system over the last 4.5 billion years," said Vondrak, a planetary scientist with NASA's Goddard Space Flight Center in Greenbelt, Md.
The study also showed that if Earth revolved around the sun in the opposite direction, called a retrograde orbit, it wouldn't need a moon at all to have a climate about as stable as it has today. Likewise, a Jupiter about half the distance to Earth as its present location would have had a similar steading hand, Barnes added.
The findings are causing extrasolar planet hunters to revise their thinking on what constitutes a habitable planet.
"We think that at least 80 or 90 percent of planets out there statistically won't even require a moon" to have a stable climate, Barnes said.
Location is key. In our own solar system, Mars shows evidence of extreme climate change, the result, scientists believe, of a rotational tilt that flips between zero and 60 degrees over time. A big moon likely could have helped stabilize Mars' orbit, but the planet has just two small moons, most likely captured asteroids, that don't have much gravitational muscle.
Read more at Discovery News
The study sprang from the ongoing Kepler Telescope mission to find Earth-like planets circling in habitable zones around other stars in the Milky Way.
"We were wondering 'Do we really have to find a moon or not?' around potentially habitable worlds, planetary scientist Jason Barnes, with the University of Idaho, told Discovery News.
Previous studies showed that without the steadying gravitational influence of a large moon, Earth's tilt would shift by as much as about 85 degrees every 100,000 years or so, alternatively freezing and baking the planet's poles. Scientists believe a stable climate spanning about 500,000 years was necessary for complex life to blossom on Earth.
A new computational analysis, however, shows that a moonless Earth would still have swings in its tilt but the influence of Jupiter and other factors would limit the variations to about 10 degrees in either direction.
Earth's rotational tilt varies between 0.5 and 1 degree about every 100,000 years.
"Plus- or minus-10 would certainly be noticeable and may be a problem, but I don't think it would prevent life from coming about," Barnes said.
"It's a very intriguing result. It's provocative," Richard Vondrak, lead scientist with NASA's ongoing Lunar Reconnaissance Orbiter mission, told Discovery News.
"On the moon we can find important evidence and clues of what happened to not only to the moon, but also to the Earth-moon system over the last 4.5 billion years," said Vondrak, a planetary scientist with NASA's Goddard Space Flight Center in Greenbelt, Md.
The study also showed that if Earth revolved around the sun in the opposite direction, called a retrograde orbit, it wouldn't need a moon at all to have a climate about as stable as it has today. Likewise, a Jupiter about half the distance to Earth as its present location would have had a similar steading hand, Barnes added.
The findings are causing extrasolar planet hunters to revise their thinking on what constitutes a habitable planet.
"We think that at least 80 or 90 percent of planets out there statistically won't even require a moon" to have a stable climate, Barnes said.
Location is key. In our own solar system, Mars shows evidence of extreme climate change, the result, scientists believe, of a rotational tilt that flips between zero and 60 degrees over time. A big moon likely could have helped stabilize Mars' orbit, but the planet has just two small moons, most likely captured asteroids, that don't have much gravitational muscle.
Read more at Discovery News
Aug 7, 2011
Potential New Eye Tumor Treatment Discovered
New research from a team including several Carnegie scientists demonstrates that a specific small segment of RNA could play a key role in the growth of a type of malignant childhood eye tumor called retinoblastoma. The tumor is associated with mutations of a protein called Rb, or retinoblastoma protein. Dysfunctional Rb is also involved with other types of cancers, including lung, brain, breast and bone.
Their work, which will be the cover story of the August 15th issue of Genes & Development, could result in a new therapeutic target for treating this rare form of cancer and potentially other cancers as well.
MicroRNAs are a short, single strands of genetic material that bind to longer strands of messenger RNA--which is the courier that brings the genetic code from the DNA in the nucleus to the cell's ribosome, where it is translated into protein. This binding activity allows microRNAs to silence the expression of select genes in a targeted manner. Abnormal versions of microRNAs have been implicated in the growth of several types of cancer.
The paper from Carnegie's Karina Conkrite, Maggie Sundby and David MacPherson--as well as authors from other institutions -- focuses on a cluster of microRNAs called miR-17~92. Recent research has shown that aberrant versions of this cluster are involved in preventing pre-cancerous cells from dying and allowing them to proliferate into tumors. Previous work has shown that miR-17~92 can be involved in the survival of lymphoma and leukemia cells by reducing the levels of a tumor-suppressing protein called PTEN.
The team's new research shows that miR-17~92 can also be involved in retinoblastoma, although it does not act in the same way, via the PTEN protein, as it does in other types of cancers. Rather, miR-17~92 acts to help cells that lack the tumor-suppressing Rb protein to proliferate.
First the team demonstrated that miR-17~92 is expressed in higher-than-usual quantities in all human retinoblastomas examined and in some mouse retinoblastomas. The authors engineered mice to express high levels of miR-17~92 in their retinas. When coupled with inactivation of Rb family members, expression of miR-17~92 led to extremely rapid and aggressive retinoblastoma. Then they showed that this abundance of miR-17~92 acts to suppress an inhibitor of proliferation, called p21Cip1, which is supposed to compensate for the loss of Rb.
More at Science Daily
Their work, which will be the cover story of the August 15th issue of Genes & Development, could result in a new therapeutic target for treating this rare form of cancer and potentially other cancers as well.
MicroRNAs are a short, single strands of genetic material that bind to longer strands of messenger RNA--which is the courier that brings the genetic code from the DNA in the nucleus to the cell's ribosome, where it is translated into protein. This binding activity allows microRNAs to silence the expression of select genes in a targeted manner. Abnormal versions of microRNAs have been implicated in the growth of several types of cancer.
The paper from Carnegie's Karina Conkrite, Maggie Sundby and David MacPherson--as well as authors from other institutions -- focuses on a cluster of microRNAs called miR-17~92. Recent research has shown that aberrant versions of this cluster are involved in preventing pre-cancerous cells from dying and allowing them to proliferate into tumors. Previous work has shown that miR-17~92 can be involved in the survival of lymphoma and leukemia cells by reducing the levels of a tumor-suppressing protein called PTEN.
The team's new research shows that miR-17~92 can also be involved in retinoblastoma, although it does not act in the same way, via the PTEN protein, as it does in other types of cancers. Rather, miR-17~92 acts to help cells that lack the tumor-suppressing Rb protein to proliferate.
First the team demonstrated that miR-17~92 is expressed in higher-than-usual quantities in all human retinoblastomas examined and in some mouse retinoblastomas. The authors engineered mice to express high levels of miR-17~92 in their retinas. When coupled with inactivation of Rb family members, expression of miR-17~92 led to extremely rapid and aggressive retinoblastoma. Then they showed that this abundance of miR-17~92 acts to suppress an inhibitor of proliferation, called p21Cip1, which is supposed to compensate for the loss of Rb.
More at Science Daily
Captain Morgan's Pirate Ship Found
The lost wreckage of a ship belonging to 17th century pirate Captain Henry Morgan has been discovered in Panama, said a team of U.S. archaeologists -- and the maker of Captain Morgan rum.
Near the Lajas Reef, where Morgan lost five ships in 1671 including his flagship "Satisfaction," the team uncovered a portion of the starboard side of a wooden ship's hull and a series of unopened cargo boxes and chests encrusted in coral.
The cargo has yet to be opened, but Captain Morgan USA -- which sells the spiced rum named for the eponymous pirate -- is clearly hoping there's liquor in there.
"There's definitely an irony in the situation," Fritz Hanselmann an archaeologist with the River Systems Institute and the Center for Archaeological Studies at Texas State University and head of the dive team told KVUE Austin. The Captain Morgan rum group stepped in on the quest for Captain Morgan after team -- which found a collection of iron cannons nearby -- ran out of funds before they could narrow down the quest.
The new funding allowed the team to do a magnetometer survey, which looks for metal by finding any deviation in the earth's magnetic field.
"When the opportunity arose for us to help make this discovery mission possible, it was a natural fit for us to get involved. The artifacts uncovered during this mission will help bring Henry Morgan and his adventures to life in a way never thought possible," said Tom Herbst, brand director of Captain Morgan USA, in a statement.
In the 17th century, Captain Henry Morgan sailed as a privateer on behalf of England, defending the Crown's interests and pioneering expeditions to the New World. In 1671, in an effort to capture Panama City and loosen the stronghold of Spain in the Caribbean, Morgan set out to take the Castillo de San Lorenzo, a Spanish fort on the cliff overlooking the entrance to the Chagres River, the only water passageway between the Caribbean and the capital city.
Read more at Discovery News
Near the Lajas Reef, where Morgan lost five ships in 1671 including his flagship "Satisfaction," the team uncovered a portion of the starboard side of a wooden ship's hull and a series of unopened cargo boxes and chests encrusted in coral.
The cargo has yet to be opened, but Captain Morgan USA -- which sells the spiced rum named for the eponymous pirate -- is clearly hoping there's liquor in there.
"There's definitely an irony in the situation," Fritz Hanselmann an archaeologist with the River Systems Institute and the Center for Archaeological Studies at Texas State University and head of the dive team told KVUE Austin. The Captain Morgan rum group stepped in on the quest for Captain Morgan after team -- which found a collection of iron cannons nearby -- ran out of funds before they could narrow down the quest.
The new funding allowed the team to do a magnetometer survey, which looks for metal by finding any deviation in the earth's magnetic field.
"When the opportunity arose for us to help make this discovery mission possible, it was a natural fit for us to get involved. The artifacts uncovered during this mission will help bring Henry Morgan and his adventures to life in a way never thought possible," said Tom Herbst, brand director of Captain Morgan USA, in a statement.
In the 17th century, Captain Henry Morgan sailed as a privateer on behalf of England, defending the Crown's interests and pioneering expeditions to the New World. In 1671, in an effort to capture Panama City and loosen the stronghold of Spain in the Caribbean, Morgan set out to take the Castillo de San Lorenzo, a Spanish fort on the cliff overlooking the entrance to the Chagres River, the only water passageway between the Caribbean and the capital city.
Read more at Discovery News
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