A space rock crashed into Earth about 12,900 years ago, wiping out some of North America's biggest beasts and ushering in a period of extreme cooling, researchers say, based on new evidence supporting this comet-crash scenario.
If such an impact took place, it did not leave behind any obvious clues like a crater. But microscopic melted rock formations called spherules and nano-size diamonds in ancient soil layers could be telltale signs of a big collision. The mix of particles could only have formed under extreme temperatures, created by a comet or asteroid impact. Researchers first reported in 2007 that these particles were found at several archaeological sites in layers of sediment 12,900 years old. Now an independent study published in the Sept.17 issue of the Proceedings of the National Academy of Sciences (PNAS) says those findings hold up. |  |
Bolivia enacts law to protect Amazon pink dolphins
Bolivian President Evo Morales has enacted a law aimed at protecting a unique species of dolphins that live in the country's Amazon rivers.
The new legislation bans fishing freshwater pink dolphins and declares the species a national treasure. At a ceremony along the shores of the Ibare river, President Morales called on the armed forces to protect the habitats of the pink dolphins. |  |
Scientists create atlas of human brain
A comprehensive atlas of the adult human brain that reveals the activity of genes across the entire organ has been created by scientists.
The map was created from genetic analyses of about 900 specific parts of two "clinically unremarkable" brains donated by a 24-year-old and 39-year-old man, and half a brain from a third man. Researchers at the Allen Institute for Brain Science in Seattle said the atlas will serve as a baseline against which they and others can compare the genetic activity of diseased brains, and so shed light on factors that underlie neurological and psychiatric conditions. |  |
Unearthed scarab proves Egyptians were in Tel Aviv
A rare scarab amulet newly unearthed in Tel Aviv reveals the ancient Egyptian presence in this modern Israeli city.
Archaeologists excavating the ancient city of Jaffa, now part of Tel Aviv, have long uncovered evidence of Egyptian influence. Now, researchers have learned that a gateway belonging to an Egyptian fortification in Jaffa was destroyed and rebuilt at least four times. They have also found the scarab, which bears the cartouche of the Egyptian Pharaoh Amenhotep III, who ruled from 1390 to 1353 B.C. Scarabs were common charms in ancient Egypt, representing the journey of the sun across the sky and the cycle of life. |  |
Administrative court orders recovery of 179 artifacts from US
EGYPT INDEPENDENT
The State Council Administrative Court on Saturday ordered the government to take the necessary procedures to recover 179 artifacts that belonged to Queen Cleopatra from the United States.
Former Prime Minister Ahmed Nazif had issued a decree to display the artifacts in the United States, based on an individual agreement signed by Zahi Hawass, the former head of the Supreme Council of Antiquities; the National Geographic Society, owned by billionaire Rupert Murdoch; and two other American associations.
The court ruled that the agreement is a violation of Article 10 of the Antiquities Protection Act, which prohibits contracts with private foreign societies to display antiquities outside Egypt.
Former Prime Minister Ahmed Nazif had issued a decree to display the artifacts in the United States, based on an individual agreement signed by Zahi Hawass, the former head of the Supreme Council of Antiquities; the National Geographic Society, owned by billionaire Rupert Murdoch; and two other American associations.
The court ruled that the agreement is a violation of Article 10 of the Antiquities Protection Act, which prohibits contracts with private foreign societies to display antiquities outside Egypt.
Interstellar Travel Is Hard, Why Bother?
Intercontinental travel will never happen. The nearest shore is thousands of miles away. This means that even if we had the ability to row five miles per day from our little island, it would take years to get there!
To rub (sea) salt into the wound, the nearest shoreline is probably not a place we'd want to visit anyway. We've heard that beasts of unimaginable horror lurk over the horizon. Even worse, what if that undiscovered country is a desert-like place, or a disease-ridden tropic? Perhaps water doesn't even flow as a liquid! Imagine trying to live in a land covered with ice. What a thought!. |  |
Dark Energy Really IS Real
Our universe is a mysterious place. Only 4 percent or so is made up of the ordinary matter we see around us, including all those galaxies filled with stars. The rest, physicists believe, is made of up weakly interacting dark matter, and a mysterious substance called dark energy that is causing the cosmos to expand at an accelerating rate.
At least, that's the working hypothesis, and it seems to fit the data, although there are scientists who question its existence and tout alternatives to explain that accelerating expansion. A new, two-year study by scientists at the University of Portsmouth and Ludwig-Maximilians-Universitat Munchen concludes that dark energy does, indeed, exist. Those results just appeared in the journal Monthly Notices of the Royal Astronomical Society. |  |
Future Jets Will Flock Together
European aerospace giant Airbus is proposing a new method of air transport that takes advantage of bird-like formations to reduce drag, save energy and fly more quickly to their destinations. The planes going in the same general direction would join together in an aerodynamic formation before splitting off to land.
Airbus' proposal for 2050 also includes robot-assisted take-off for passenger jets, (just like fighters on carrier decks) to shorten runways and get planes to cruising altitude more quickly. The company claims shorter runways will also take up less land and produce fewer carbon emissions. |  |
Enough wind to power global energy demand, new research says
There is enough energy available in winds to meet all of the world's demand. Atmospheric turbines that convert steadier and faster high-altitude winds into energy could generate even more power than ground- and ocean-based units. New research from Carnegie's Ken Caldeira examines the limits of the amount of power that could be harvested from winds, as well as the effects high-altitude wind power could have on the climate as a whole. Their work is published September 9 by Nature Climate Change.
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Gamechanging Natural Gas Tech Gets Green Lighta
In April, the U.S. Department of Energy and an international consortium of major oil and gas companies completed an unprecedented two-month proof-of-concept test in the North Slope of Alaska. The experiment was supposed to show that a steady flow of methane molecules could be extracted from a substance known as methane or gas hydrates submerged under the sea floor.
It worked and the world moved one step closer to tapping gas hydrates, the most abundant fossil fuel resource on Earth. |  |
Nuclear Fuel From the Sea
Next time you go to the beach, think about this: You’re swimming in nuclear fuel. Our oceans contain an estimated 4.5 billion metric tons of uranium, diluted down to a minuscule 3.3 parts per billion. The idea of extracting uranium from seawater has been kicking around for decades now, but the materials and processes to do so may finally be economically viable.
The best method works like this: A polymer substrate—basically, plastic—is irradiated, and then chemicals with an affinity for uranium are grafted onto it. The material is woven into 60-meter-long braids, and these are then brought out by boat to water at least 100 meters deep. The braids are chained to the ocean floor and allowed to float passively in the water, like an artificial kelp forest. After about 60 days, the boat returns and pulls in the adsorbent materials—now sporting a healthy yellow tint from the uranium. The plastic is then brought back to shore, and the uranium is eluted off. |  |
Bee study lifts lid on hive habits
Experiments on the division of labour in honeybee hives have revealed why some bees do the waggle dance while others nurse their queens.
The roles require drastically different behaviours, with nurses feeding the larvae and performing royal grooming duties, and foragers navigating great distances and performing complex dance routines to point others in the direction of rich sources of nectar. According to a report in the journal Nature Neuroscience, the job a worker bee does corresponds to distinct patterns of chemicals that latch on to and regulate certain genes in their brains. |  |
Birds of a feather flock together, even in death
How do birds react when a member of their flock dies? Apparently, for western scrub jays, commotion ensues.
These birds call loudly when they come upon another jay that is dead, attracting nearby birds, which often join in the noise. A team of scientists from UC Davis hypothesized that these “cacophonous aggregations” may function to warn other birds of potential danger. To test this hypothesis, the scientists tracked the response of the birds to a dead jay laying on the ground, and compared those with the birds’ reactions to three other stimuli: a stuffed and mounted jay, a stuffed and mounted great horned owl, and a neutral object that was somewhat similar in shape and color to a dead bird (painted pieces of wood). |  |
The Rock of Gibraltar: Neanderthals’ Last Refuge
I was intrigued when I saw this headline over at NPR’s 13.7 blog earlier this week: “A Neanderthal-Themed Park for Gibraltar?“ As it turns out, no one’s planning a human evolution Disney World along Gibraltar’s cliffs. Instead, government officials are hoping one of the area’s caves will become a Unesco World Heritage site. Gibraltar certainly deserves that distinction. The southwestern tip of Europe’s Iberian Peninsula, Gibraltar was home to the last-surviving Neanderthals. And then tens of thousands of years later, it became the site of one of the first Neanderthal fossil discoveries.
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Ancient Baby Graveyard Not for Child Sacrifice, Scientists Say
A Carthaginian burial site was not for child sacrifice but was instead a graveyard for babies and fetuses, researchers now say.
A new study of the ancient North African site offers the latest volley in a debate over the primary purpose of the graveyard, long thought to be a place of sacred sacrifice. "It's all very great, cinematic stuff, but whether that was a constant daily activity ― I think our analysis contradicts that," said study co-author Jeffrey Schwartz of the University of Pittsburgh. |  |
Arctic expert predicts final collapse of sea ice within four years
One of the world's leading ice experts has predicted the final collapse of Arctic sea ice in summer months within four years.
In what he calls a "global disaster" now unfolding in northern latitudes as the sea area that freezes and melts each year shrinks to its lowest extent ever recorded, Prof Peter Wadhams of Cambridge University calls for "urgent" consideration of new ideas to reduce global temperatures. In an email to the Guardian he says: "Climate change is no longer something we can aim to do something about in a few decades' time, and that we must not only urgently reduce CO2 emissions but must urgently examine other ways of slowing global warming, such as the various geoengineering ideas that have been put forward.". |  |
Sir Ranulph Fiennes to attempt record Antarctica trek
British explorer Sir Ranulph Fiennes is to lead the first team on foot across Antarctica during the southern winter.
The six-month expedition next year is being called the Coldest Journey, crossing terrain where the temperature has hit -90C. It will be 68-year-old Sir Ranulph's latest record attempt. Past feats have seen him go pole to pole and climb Everest as a pensioner. Guinness World Records describes him as the world's greatest living explorer. |  |
Study links chemical BPA to obesity in white children
Deepening the mystery surrounding the health effects of bisphenol A, a large new study has linked high levels of childhood and adolescent exposure to the industrial chemical to higher rates of obesity — in white children only.
The latest research, published in the Journal of the American Medical Assn., measured bisphenol A, or BPA, levels in the urine of a diverse group of 2,838 Americans ages 6 to 19. Researchers from New York University also reviewed data on the participants' weight, dietary intake, physical activity and socioeconomic backgrounds.
At first blush, the link between BPA and obesity appeared to be powerful: Compared with children and teens with the lowest apparent exposure to the ubiquitous chemical, those with the highest exposure were roughly 2.5 times more likely to be obese.
The latest research, published in the Journal of the American Medical Assn., measured bisphenol A, or BPA, levels in the urine of a diverse group of 2,838 Americans ages 6 to 19. Researchers from New York University also reviewed data on the participants' weight, dietary intake, physical activity and socioeconomic backgrounds.
At first blush, the link between BPA and obesity appeared to be powerful: Compared with children and teens with the lowest apparent exposure to the ubiquitous chemical, those with the highest exposure were roughly 2.5 times more likely to be obese.
Oldest dental filling is found in a Stone Age tooth
You may not want to try this at home. A simple wax cap that was applied to a broken tooth 6500 years ago is the oldest dental filling on record. It adds to evidence that Neolithic communities had a surprisingly sophisticated knowledge of dentistry.
The recipient of the treatment was most likely a 24 to 30-year-old man, living in what is now Slovenia. His fossilised jawbone was found early last century near the village of Lonche. At the time, the find – one of the oldest human bones ever found in the region – was described, catalogued and filed away in a museum in nearby Trieste, Italy. images here |  |
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