Mar 17, 2012

Australian Saltwater Crocodiles Are World’s Most Powerful Biters

In Greg Erickson's lab at Florida State University, crocodiles and alligators rule. Skeletal snouts and toothy grins adorn window ledges and tables -- all donated specimens that are scrutinized by researchers and students alike.

Lately, Erickson, a Florida State biology professor, and his colleagues have been pondering a particularly painful-sounding question: How hard do alligators and crocodiles bite?

The answer is a bite force value of 3,700 pounds for a 17-foot saltwater crocodile (as well as tooth pressures of 350,000 pounds per square inch). That's the highest bite force ever recorded -- beating a 2,980-pound value for a 13-foot wild American alligator Erickson's lab measured in 2005. They estimate that the largest extinct crocodilians, 35- to 40-foot animals, bit at forces as high as 23,100 pounds.

Erickson, along with several colleagues, including Florida State biology professors Scott Steppan and Brian Inouye, and graduate student Paul Gignac, reported their findings in the journal PLoS One.

Funded by the National Geographic Society and the FSU College of Arts and Sciences, their study looks at the bite force and tooth pressure of every single species of crocodilian. It took more than a decade to complete and required a wily team of croc handlers and statisticians, as well as an army of undergraduate and graduate students. Erickson describes crocodilian bite-force testing as being a bit like dragon slaying by committee.

"Our work required a team effort," he said.

As a result of the study, Erickson and his team have a new understanding on how these animals became so successful and a better understanding about the remarkable biology of living crocodiles and alligators. They've also developed new methods for testing bite forces.

The data contributes to analyzing performance in animals from the past and provides unprecedented insights on evolution and statistically informed models about other reptiles such as dinosaurs.

The study's findings are so unique that Erickson's team has been contacted by editors at the "Guinness Book of World Records" inquiring about the data.

Over the 11 years that his current study took place in both the United States and Australia, Erickson and his team roped 83 adult alligators and crocodiles, strapped them down, placed a bite-force device between their back teeth and recorded the bite force. An engineering calculation was then used to estimate the force generated simultaneously by the teeth nearest the front of the jaws. The team molded the teeth with dentist's dental putty, made casts and figured out the contact areas.

Talk about dangerous work.

As Erickson describes it: "I have to admit, the first time I placed our meter into the maw of an adult crocodile, I was nervous. It was all over in the blink of an eye. When it struck, it nearly wrested my grip from the handle. The noise of the jaws coming together was like a gunshot. The power of the animal was astounding, and the violence of the event frightening."

Overall, the researchers looked at crocodilians both mundane and exotic, from American alligators to 17-foot Australian saltwater crocodiles and the Indian gharial. Among the world's most successful predatory reptiles, these creatures have been "guardians of the water-land interface for over 85 million years," Erickson said.

But just how they were able to occupy and dominate ecological niches for so long is a mystery.

Erickson and his team knew that the reptiles evolved into different sizes, from 3-footers to 40-footers, and they showed concurrent major changes in their jaw shape and tooth form, while their body form remained largely unchanged.

"We set out to answer how this anatomical variance related to their ability to generate bite force and pressures for feeding in the different forms and thus how they have been so successful," Erickson said. "The bite force over the contact area is the pressure, which is more pertinent to feeding performance than bite force. Ultimately, it tells us just what they were doing with those prodigious bite forces."

And, he added, gators and crocs have comparable maximal bite-force capacity when measured pound for pound. They basically all have the same musculoskeletal design, just different snouts and teeth.

"It is analogous to putting different attachments on a weed eater -- grass cutter, brush cutter, tree trimmer, they all have the same type of engine," Erickson said. "There are bigger and smaller engines, with higher and lower horsepower, but they have the same attachments."

His research team is already using the study's data to explore bite-force and tooth-pressure performance in fossil forms. The team is building the world's most sophisticated models for extinct crocodiles and dinosaurs based on the findings, as well as continuing to study the significance of croc snout form.

As for modern-day crocs and gators, well, there's little doubt that they are truly the world's bone-crushing champions. Just remember that old Floridian maxim: Always maintain a healthy distance between yourself and the nearest gator.

Read more at Science Daily

Past in Monsoon Changes Linked to Major Shifts in Indian Civilizations

A fundamental shift in the Indian monsoon has occurred over the last few millennia, from a steady humid monsoon that favored lush vegetation to extended periods of drought, reports a new study led by researchers at the Woods Hole Oceanographic Institution (WHOI). The study has implications for our understanding of the monsoon’s response to climate change.

The Indian peninsula sustains over a billion people, yet it lies at the same latitude as the Sahara Desert. Without a monsoon, most of India would be dry and uninhabitable. The ability to predict the timing and amount of the next year’s monsoon is vital, yet even our knowledge of the monsoon’s past variability remains incomplete.

One key to this understanding lies in the core monsoon zone (CMZ) – a region in the central part of India that is a very sensitive indicator of the monsoon throughout the India peninsula.

“If you know what’s happening there, you know more or less what’s happening in the rest of India,” said Camilo Ponton, a student in the MIT-WHOI Joint Program in Oceanography and lead author of the study recently published in Geophysical Research Letters entitled "Holocene Aridification of India". “Our biggest problem has been a lack of evidence from this region to extend the short, existing records.”

The study was designed by WHOI geologist Liviu Giosan and geochemist Tim Eglinton, now at ETH in Zurich, and makes use of a sediment core collected by the National Gas Hydrate Program of India in 2006. Sailing around India aboard the drilling vessel JOIDES Resolution for several months, Giosan enlisted colleagues from India and US to help with the project.  Extracted from a “sweet spot” in the Bay of Bengal where the Godavari River drains the central Indian peninsula and over which monsoon winds carry most of the precipitation, the core has provided the basis for a 10,000-year reconstruction of climate in the Indian peninsula’s CMZ .

 “We are fortunate to have this core from close to the river mouth, where it accumulates sediment very fast,” said Ponton. “Every centimeter of sediment contains 10 to 20 years’ worth of information. So it gives us the advantage of high temporal resolution to address the problems.”

When put together, the research tells the story of growing aridity in India, enables valuable insights into the impact of the monsoon on past cultures, and points scientists toward a way to model future monsoons.

To assemble the 10,000-year record, the team looked to both what the land and the ocean could tell them.  Contained within the sediment core’s layers are microscopic compounds from the trees, grasses, and shrubs that lived in the region and remnants of plankton fossils from the ocean.

 “The geochemical analyses of the leaf waxes tell a simple story,” said Giosan.  “About 10,000 years ago to about 4500 ago, the Godavari River drained mostly terrain that had humidity-loving plants. Stepwise changes starting at around 4,000 years ago and again after 1,700 years ago changed the flora toward aridity-adapted plants. That tells us that central India – the core monsoon zone – became drier.”

Analyses of the plankton fossils support the story reconstructed from plant remains and reveal a record of unprecedented spikes and troughs in the Bay of Bengal’s salinity – becoming saltier during drought periods and fresher when water from the monsoon filled the river and rained into the Bay.  Similar drought periods have been documented in shorter records from tree rings and cave stalagmites within India lending further support to this interpretation.

With a picture emerging of changes in the ancient flora of India, Giosan tapped archaeobotanist Dorian Fuller’s interest.

“What the new paleo-climatic information makes clear is that the shift towards more arid conditions around 4,000 years ago corresponds to the time when agricultural populations expanded and settled village life began,” says Fuller of the Institute of Archaeology, University College London. “Arid-adapted food production is an old cultural tradition in the region, with cultivation of drought-tolerant millets and soil-restoring bean species. There may be lessons to learn here, as these drought-tolerant agricultural traditions have eroded over the past century, with shift towards more water and chemical intensive forms of modern agriculture.”

Together, the geological record and the archaeological evidence tell a story of the possible fate of India’s earliest civilizations. Cultural changes occurred across the Indian subcontinent as the climate became more arid after ~4,000 years. In the already dry Indus basin, the urban Harappan civilization failed to adapt to even harsher conditions and slowly collapsed. But aridity favored an increase in sophistication in the central and south India where tropical forest decreased in extent and people began to settle and do more agriculture. Human resourcefulness proved again crucial in the rapid proliferation of rain-collecting water tanks across the Indian peninsula, just as the long series of droughts settled in over the last 1,700 years.

What can this record tell us about future Indian monsoons? According to Ponton, “How the monsoon will behave in the future is highly controversial. Our research provides clues for modeling and that could help determine whether the monsoon will increase or decrease with global warming.”

The study found that the type of monsoon and its droughts are a function of the Northern Hemisphere’s incoming solar radiation – or “insolation.”  Every year, the band of heavy rain known as the Inter-Tropical Convergence Zone, or ITCZ, moves north over India.

Read more at Science Daily

Mar 16, 2012

European Grasslands Challenge Rainforests as the Most Species-Rich Spaces On Earth

The city of Manila holds the human world record for the most densely populated space and now an international team of ecologists are seeking the natural equivalent, the most species rich area on earth. The team's findings, published in the Journal of Vegetation Science, reveal the record is contested between South America's tropical rainforests and Central European meadows.

"The coexistence of large numbers of species in one space and the questions it raises have long fascinated ecologists," said Professor Bastow Wilson, from the University of Otago, New Zealand. "For example it's a core ecological principle that two species occupying the same niche cannot co-exist long-term, so how can 942 plant species co-exist in one hectare of tropical rainforest?"

While tropical rainforests of South America and Central Africa are often believed to be the most species rich areas on Earth, Professor Wilson's team sought to establish if this is true, especially if smaller spatial scales are analysed.

"We surveyed the global literature to find records of plant species richness at scales from 1 mm² up to 1 hectare. Above 50 m², all the maximum values were from tropical rainforests in Costa Rica, Columbia or Ecuador," said Wilson. "However, looking at smaller scales we have found that long-grazed or mown grasslands are the most species rich places on Earth."

These very rich grasslands were found in the eastern half of Europe, from the German border through to Romania, although two examples were also found in Argentina. Most were over limestone, and two were from wooded meadow, a landscape once common over northern Europe but now very rare.

Using these data the team asked if there is a theoretical maximum for the number of species which can co-exist in one area. They extrapolated the relationship up to 1 hectare, predicting the number of plant species over the whole earth.

Read more at Science Daily

Live Cells 'Printed' Using Standard Inkjet Printer

Researchers from Clemson University have found a way to create temporary holes in the membranes of live cells using a standard inkjet printer.

The method will be published in JoVE, the Journal of Visualized Experiments, on March 16.

"We first had the idea for this method when we wanted to be able to visualize changes in the cytoskeleton arrangement due to applied forces on cells," said paper-author Dr. Delphine Dean.

She said other researchers have been using this method to print cells onto slides, but that they have only recently discovered that printing the cells causes the disruption in their membranes for a few hours. Creating temporary pores allow researchers to put molecules inside of cells that wouldn't otherwise fit, and study how the cells react.

"The authors have used an extremely innovative approach for bioprinting cells. Moreover, this approach can be used for applications other than cell printing," said JoVE Science Editor, Dr. Nandita Singh. "Matrix proteins can be printed onto substrates with this technique for cell patterning. This JoVE publication will make this approach simple and approachable and enable other labs to replicate the procedure."

The printer is modified by removing the paperfeed mechanism and adding a "stage" from which to feed the slides. The ink is replaced with a cell solution, and the cells are printed directly on to the slides.

Using this method, the researchers are able to process thousands of cells in a matter of minutes. Dr. Dean's team used the holes to introduce fluorescent molecules that illuminate the skeleton of the cell.

Read more at Science Daily

Miniature 'Triceratops' Ancestor Discovered

The oldest and smallest horned dinosaur in North America finally gets a name after decades of research.

The little horned dinosaur (Gryphoceratops morrisoni), measuring 1.6 feet (0.5 meters) long, lived about 83 million years ago.

The new study, published in the journal Cretaceous Research on Jan 24, also details another newly named species of horned dinosaur: Unescopceratops koppelhusae, which lived 75 million years ago, in what is now Alberta, Canada.

"These dinosaurs fill important gaps in the evolutionary history of small-bodied horned dinosaurs that lack the large horns and frills of relatives like Triceratops from North America," study researcher Michael Ryan, curator at The Cleveland Museum of Natural History, said in a statement. "Although horned dinosaurs originated in Asia, our analysis suggests that leptoceratopsids [which includes these horned dinosaurs] radiated to North America and diversified here, since the new species, Gryphoceratops, is the earliest record of the group on this continent."

The first jaw fragment of U. Koppelhusae was discovered in Dinosaur Provincial Park in 1995, but has just recently gotten a name; the other, G. morrisoni, was first discovered in 1950, but remained unnamed until recently.

The duo was much smaller than their larger Triceratops and Torosaurus relatives: U. koppelhusae measured about 6.5 feet (about 2 m) in length and weighed less than 200 pounds (91 kilograms). The researchers consider the other newbie, G. morrisoni, the smallest horned dinosaur in North America and one of the smallest plant-eating dinosaurs known.

Read more at Discovery News

Faster-Than-Light Neutrinos (Probably) Don't Exist

Neutrinos do not go faster than light, according to fresh measurements of a test last year that had suggested the particles broke the Universe's speed limit, CERN said on Friday.

The new measurements were made by a team working independently from the scientists who had made the tentative but hugely controversial claim about "faster-than-light" particles.

Their findings "indicate the neutrinos do not exceed the speed of light," the European Center for Nuclear Research (CERN) said in a press release.

CERN said last month there may have been technical hitches that had skewed the initial measurements, something that critics of the findings said they had always suspected.

The controversy began last September, when CERN's OPERA team cautiously announced that sub-atomic particles called neutrinos had traveled some six kilometers (nearly four miles) per second faster than the velocity of light, described by Einstein as the maximum speed in the cosmos.

The neutrinos were timed at their departure from CERN's giant underground lab near Geneva and again, after traveling 732 km (454 miles) through the Earth's crust, at their arrival at the Gran Sasso Laboratory in Italy.

To do the trip, the neutrinos should have taken 0.0024 seconds. Instead, the particles were recorded as hitting the detectors in Italy 0.00000006 seconds sooner than expected.

Knowing their findings would stir a storm, the OPERA team urged other physicists to carry out their own checks to corroborate or refute what had been seen.

As part of this verification, an experiment called ICARUS at the Gran Sasso Laboratory took a separate look at the flight of seven neutrinos that had also been recorded by the OPERA team.

It used a new measuring technique, called a liquid argon time projection chamber.

"ICARUS measures the neutrino's velocity to be no faster than the speed of light," said Carlo Rubbia, a Nobel winner and spokesperson for the ICARUS project.

But he and CERN Research Director Sergio Bertolucci stoutly defended the rights of scientists to make exceptional claims and to the rights of others to verify them.

"Whatever the result, the OPERA experiment has behaved with perfect scientific integrity in opening their measurement to broad scrutiny and inviting independent measurements. This is how science works," said Bertolucci.

Read more at Discovery News

Mar 15, 2012

Basketball-Sized Eyes Help Squids Play Defense

Giant and colossal squids have eyes as big as basketballs, and a Duke scientist thinks he knows why. "They're most likely using their huge eyes to spot and escape their predators, sperm whales," said Duke biologist Sonke Johnsen.

Johnsen collaborated with a group of biologists to model, both physically and biologically, how and why a squid uses such a big eye. The team found that the design and size of the eye give squids the ability to see approaching sperm whales as they disturb bioluminescent organisms. The study appears in the March 15 Current Biology.

Big squids come in two types -- giant and colossal. They can grow to weights of five adult men put together, which is comparable to a large swordfish. But swordfish eyes are about the size of softballs, about 3 inches in diameter.

"It doesn't make sense a giant squid and swordfish are similar in size but the squid's eyes are proportionally much larger, three times the diameter and 27 times the volume," Johnsen said. "The question is why. Why do giant squid need such large eyes?"

To explain the squids' eye size, Johnsen and his collaborators first measured giant and colossal squid eyes using photos and captured animals. They also found data on the water clarity and amount of light at the ocean depths where the squid live -- typically 300 to 1000 meters. Using this information, the scientists began to mathematically model how the creatures' eyes would work and what they could see.

The team found that the squids' large eyes collect more light compared to animals of similar size but with smaller eyes. The extra light intake improves the squid's ability to detect small contrast differences under the dim conditions of the deep ocean, they argue. Johnsen said this ability doesn't matter much to the majority of deep-sea animals, which are looking at small objects that become too small to see before they fade away.

But the boost in being able to sense contrast, which large eyes provide, is critical for detecting the low light differences of large, distant objects, the most important one being the bioluminescence stimulated by large animals such as approaching sperm whales, Johnsen said.

The team realized that sperm whales dive and swim continuously while emitting sonar to ping the squid. The cephalopods are deaf to the sonar, but the whale's wake triggers small organisms like plankton to produce light. Based on the design of the squid's eye, the animal could see this light, though contrast is low, over "freakishly long distances," about 120 meters -- the length of an American football field, Johnson said.

The contrast is low because water absorbs and scatters the light as it travels from the glowing plankton to the squid's eye. Bigger eyes mean seeing more of the faint light and predicting a predator's approach. But Johnson said a sperm whale's sonar would probably still detect the squid before it sees the light. As a result, the squid's basketball-sized eye, and the body to carry it, isn't necessarily for moving out of the whale's detection range, but for planning a well-timed escape.

"It's the predation by large, toothed whales that has driven the evolution of gigantism in the eyes of these squid," Johnsen said.

"I like the idea. The paper is speculative, however," said Michael Land, a University of Sussex zoologist who was not involved in the study. "Big eyes are always better, and the laws of growth that tend to make large vertebrates have relatively smaller eyes may not apply to cephalopods. Maybe they just grow that big," he said.

The scientists do extend their theory beyond squid to explain how ichthyosaurs, a type of swimming dinosaur, also may have used oversized eyes for detecting large targets, such as other marine dinosaurs, in the dim light of the deep ocean.

Read more at Science Daily

Believing the Impossible: No Evidence for Existence of Psychic Ability Found

Research failing to find evidence for the existence of psychic ability has been published, following a year of industry debate. The report is a response by a group of independent researchers to the 2011 study from social psychologist Daryl Bem, purporting the existence of precognition -- an ability to perceive future events.

Professor Chris French (Goldsmiths, University of London), Stuart Ritchie (University of Edinburgh) and Professor Richard Wiseman (University of Hertfordshire) collaborated to accurately replicate Bem's final experiment, and found no evidence for precognition. Their negative results have now been published by open access journal PLoS ONE.

Their report was rejected by the Journal of Personality and Social Psychology (JPSP), which originally published Bem's findings along with his appeal to independent researchers to attempt replications.

"Our submission was rejected without being sent for peer review on the basis that the journal has a policy of not publishing replications," said Professor Chris French. "Our paper has opened up the debate on the proper place of replication in the scientific literature."

In Bem's experiment, after completing a memory test on a list of words, participants were then shown a random selection of half the words from the original list. Results showed that participants were better at remembering the words they were about to be shown, indicating they had reached forward in time to 'practice' those words in the future.

Within parapsychology, there is a tendency to accept any positive replications but to dismiss failures to replicate if the procedures followed have not been exactly duplicated.

"We went to great pains to ensure we followed the same procedures as Bem," said Stuart Ritchie. "Using Bem's own computer programme and stats methods, we replicated his experiment three times, at each of our respective campuses, with the same number of participants as the original study."

Read more at Science Daily

Even This New Frog Is Trying to Make it In New York

Amazed biologists have uncovered a new species of frog in the jungle -- New York's concrete jungle.

The mottled green creature was for years mistaken as belonging to a widespread variety of the leopard frog. But now scientists realize this is new.

"For a new species to go unrecognized in this area is amazing," UCLA biologist Brad Shaffer said Wednesday.

New York is surrounded by wetlands and other nature-filled areas. But this latest urban creature appears to have chosen one of the grittiest corners as the center of its habitat: Yankee Stadium in the Bronx.

In the journal Molecular Phylogenetics and Evolution, Shaffer and other scientists compared the frog's DNA to that of other leopard frog species in the region. That's when they understood they were looking at a leopard frog, but a different kind.

"Many amphibians are secretive and very hard to find, but these frogs are pretty obvious animals," said Shaffer.

"This shows that even in the largest city in the US, there are still new and important species waiting to be discovered."

Lead paper author Cathy Newman, now of Louisiana State University, was studying leopard frogs when her colleague Jeremy Feinberg at Rutgers University asked her to probe some "unusual frogs."

Read more at Discovery News

Three Minutes of Violent Lunar Evolution

 In this recently released animation from NASA's Goddard Spaceflight Center celebrating the Lunar Reconnaissance Orbiter's 1,000th day in orbit around the Earth's only natural satellite, the moon's entire formation history has been compressed into under three minutes.

The moon's surface is often viewed as being static and unchanging. While this may be true from the perspective of we Earthlings down here, if you look at 4.5 billion years of lunar evolution, you find that the moon was actually pretty action packed! And helpfully, as the moon has no eroding atmosphere and no plate tectonics (unlike Earth), the surface features depicting the awesome violence of the early solar system are eternally etched into the moon's 'face.'

This is one of the most important scientific factors for any future manned mission to the moon: to "read" the lunar "open book." As the solar system evolved through its orbit around the galactic core, there is invaluable information etched deep into the moon's rock, not only providing information about the evolution of our own planet, but the evolution of our entire galaxy. It is akin to a cosmic photographic plate, exposed to the radiation and meteorite impacts for billions of years.

Read more at Discovery News

Mar 14, 2012

Developmental 'Scaffold' for Vertebrate Brain Found in Brainless Marine Worm

The origin of the exquisitely complex vertebrate brain is somewhat mysterious. "In terms of evolution, it basically pops up out of nowhere. You don't see anything anatomically like it in other animals," says Ariel Pani, an investigator at the Marine Biological Laboratory (MBL) in Woods Hole and a graduate student at the University of Chicago.

But recently in the journal Nature, Pani and colleagues report finding some of the genetic processes that regulate vertebrate brain development in (of all places) the acorn worm, a brainless, burrowing marine invertebrate that they collected from Waquoit Bay in Falmouth, Mass.

The scientists were searching for ancestral evidence of three "signaling centers" in the vertebrate embryo that are major components of an "invisible scaffold that sets up the foundation of how the brain develops," Pani says. Diagnostic molecular features of these signaling centers are mostly missing in the sea squirts and the lancelets, the invertebrate chordates that are the closest evolutionary relatives of the vertebrates. This had suggested that these signaling centers are key innovations that arose de novo in the vertebrate lineage.

Yet, surprisingly, the scientists found highly similar signaling centers in the more distantly related acorn worm (Saccoglossus kowalevskii), a hemichordate. Acorn worm embryos lack nervous system structures comparable to vertebrate brains, and their lineages diverged from vertebrates more than 500 million years ago. Pani and colleagues found that, in the acorn worm, the signaling centers direct the formation of the embryonic body plan.

"What this means is the last (common) ancestor of the hemichordates and the vertebrates, even though it presumably did not have a vertebrate-like nervous system, had some very complex and vertebrate-like mechanisms for establishing its body plan," Pani says. "And one of the broad implications is that weird, squishy marine animals can be very informative in terms of understanding the evolution of vertebrate development and genetics in a way that you wouldn't expect."

But the sea squirt shouldn't worry: it has not been usurped by the acorn worm. "The lancelet and ascidians (sea squirts) will still be the first animals we will look at if we want to understand vertebrate evolution. But if we find differences, we now know it is important to look at anatomically divergent animals, where you wouldn't have previously expected to find compelling similarities," Pani says. "I think this principle applies broadly to understanding animal evolution."

The MBL, where more than 200 different types of marine animals are collected and maintained, has long been a center for comparative studies of evolution and development. "It is a valuable perspective that scientists can now implement in a pretty straightforward way," Pani says. "Because of the advances in gene sequencing and developmental techniques, a lot of researchers are now free to pick an animal in an interesting place (in the evolutionary tree) and pursue research on it at a speed that wasn't possible before. I think that is going to have a really big impact."

Read more at Science Daily

Encyclopaedia Britannica Ends Print Edition

The Encyclopaedia Britannica -- which has been in print continuously since its beginnings in Edinburgh, Scotland, in 1768 -- is finally abandoning print and moving exclusively online.

The current print run of the venerable encyclopedia will be the last, the company announced Wed., March 14, as the publisher continues an evolution into digital products begun over 20 years ago -- and ends the print version after 244 years.

"It’s the oldest continuously printed reference work in the English language,” Tom Panelas, a spokesman for Encyclopaedia Britannica, told In that time the company has printed a little over seven million copies, he said.

The Encyclopaedia Britannica began exploring digital publishing in the 1970s, and created its first digital version -- likely the first digital encyclopedia ever -- for LexisNexis users in 1981. That lengthy history of online information may come as a surprise to many.

“Many people know us as the publisher of those big multivolume encyclopedias that have been a source of joy and learning since 1768. Today that encyclopedia is chiefly to be found in a multitude of digital forms that are updated daily,” the company’s website says.

“We reach a lot more people now online than we ever did before,” Panelas said. And despite the end of print, some traditions will continue, explained Jorge Zauz, president of Encyclopaedia Britannica.

"The real tradition is not whether or not we print but that we bring scholarly knowledge to as many knowledge seekers as we can," Zauz told "That tradition we’re very happy to continue."

As the company switches off the presses, it faces new forms of competition, notably Wikipedia, the community-driven online encyclopedia that many have come to rely upon. Zauz acknowledged that site's prominence but cautioned that its quality might not be on a par.

"We are a very different type of knowledge base, one that is by the nature of what we do, significantly smaller than Wikipedia -- but much more reliable," he told "Right now everyone knows Google loves Wikipedia. 96 percent of the time its in the top five [search results]. It’s a pity that Britannica can’t take that position too.”

Read more at Discovery News

Sharpest Teeth of All Time: Jawless

See these fearsome fangs? They just won the record for sharpest teeth of all time. Funny thing is, they’re invisible (without a microscope).

With tips only one-twentieth the width of a human hair, these minute munchers belonged to an ancient, eel-like animal known as a conodont, which died out about the time dinosaurs began their reign, 200 million years ago.

Each tiny conodont, only about two inches long, had a paired set of these precise pincers but neither the bony jaws nor the strong jaw muscles most blunter-toothed beings use to bite down on bits of food. So, how did they eat?

Paleontologist David Jones of the University of Bristol in the U.K. says the unbeatable sharpness of conodont teeth is precisely what made them so effective.

“In most big animals with teeth embedded in bony jaws, sharp teeth would quickly break and wear down under the pounding they would suffer under those large forces,” Jones told Discovery News. “In small animals by contrast, especially those without jaws, only tiny forces could be brought to bear on food, so it seems teeth must be very sharp to concentrate these forces efficiently.”

In a report published today in Proceedings of the Royal Society B, Jones and his colleagues describe how they used x-rays to create virtual models of conodont teeth. Combined with an engineering technique (finite element analysis) they used to analyze the stress on individual teeth of the conodont species Wurmiella excavata, the team was also able to discover how the paired sets of teeth worked together.

Read more at Discovery News

Mysterious Dark-Skinned Stone Age People Found

A newly found Stone Age people featured darker skin, an unusual mix of primitive and modern features and had a strong taste for venison.

Remains of possibly four individuals of the so-called "Red Deer Cave People" were unearthed in southwest China and may represent a new species of human.

The fossils from two caves, date to just 14,500 to 11,500 years ago. Until now, no hominid remains younger than 100,000 years old have been found in mainland East Asia resembling any other species than our own.

"We have discovered a new population of prehistoric humans whose skulls are an unusual mosaic of primitive, modern and unique features -- like nothing we've seen before," said Darren Curnoe, associate professor in the School of Biological, Earth & Environmental Sciences at the University of New South Wales and lead author of a study about the find in the journal PLoS One.

"They have rounded brain cases with prominent brow ridges, flat but short faces with a broad nose, jutting jaws that lack a human chin, their brains are moderate in size with modern-looking frontal lobes but primitive short parietal lobes, and they have large molar teeth," added Curnoe.

Since the prehistoric humans lived in areas with a lot of sunlight and ultraviolet radiation, they were likely dark-skinned.

Ji Xueping of the Yunnan Institute of Cultural Relics and Archaeology, Curnoe and their colleagues studied the fossils, which represent the remains of at least three individuals.

For now, the mysterious humans are being called the "Red Deer Cave people," since one of the caves where they were found is Maludong (meaning Red Deer Cave) and these individuals loved that animal.

"They clearly had a taste for venison, with evidence they hunted and cooked these large deer in the cave," Curnoe explained.

These people may represent an entirely new evolutionary line on the human family tree.

"First, their skulls are anatomically unique," he said. "They look very different to all modern humans, whether alive today or in Africa 150,000 years ago. And second, the very fact they persisted until almost 11,000 years ago when we know that very modern-looking people lived at the same time immediately to the east and south suggests they must have been isolated from them."

The isolation suggests that if the Red Deer Cave people did interbreed, they did so in a limited way. The nearby modern humans at this time were the last hunter-gatherers known to this region. They had just begun to make pottery for food storage and to gather rice. Both activities mark the first steps toward full-blown farming.

It is possible that the mysterious Stone Age people might represent a very early and previously unknown migration of modern humans out of Africa. This population may not have contributed genetically to living people.

"What the discovery shows is just how complicated, how interesting, human evolutionary history was in Asia right at the end of the Ice Age," Curnoe said.

"We had multiple populations living the area, probably representing different evolutionary lines: the Red Deer Cave people on the East Asian continent, Homo floresiensis (aka the "Hobbit" human) on the island of Flores in western Indonesia, and modern humans widely dispersed from northeast Asia to Australia.

He added, "This paints an amazing picture of diversity, one we had no clue about until the last decade. It's probably the tip of the iceberg of diversity, the opening of a new chapter in recent human evolution: the East Asian chapter."

Read more at Discovery News

Mar 13, 2012

Early Evolution of Life: Study of Ribosome Evolution Challenges 'RNA World' Hypothesis

In the beginning -- of the ribosome, the cell's protein-building workbench -- there were ribonucleic acids, the molecules we call RNA that today perform a host of vital functions in cells. And according to a new analysis, even before the ribosome's many working parts were recruited for protein synthesis, proteins also were on the scene and interacting with RNA. This finding challenges a long-held hypothesis about the early evolution of life.

The study appears in the journal PLoS ONE.

The "RNA world" hypothesis, first promoted in 1986 in a paper in the journal Nature and defended and elaborated on for more than 25 years, posits that the first stages of molecular evolution involved RNA and not proteins, and that proteins (and DNA) emerged later, said University of Illinois crop sciences and Institute for Genomic Biology professor Gustavo Caetano-Anollés, who led the new study. "I'm convinced that the RNA world (hypothesis) is not correct," Caetano-Anollés said. "That world of nucleic acids could not have existed if not tethered to proteins."

The ribosome is a "ribonucleoprotein machine," a complex that can have as many as 80 proteins interacting with multiple RNA molecules, so it makes sense that this assemblage is the result of a long and complicated process of gradual co-evolution, Caetano-Anollés said. Furthermore, "you can't get RNA to perform the molecular function of protein synthesis that is necessary for the cell by itself."

Proponents of the RNA world hypothesis make basic assumptions about the evolutionary origins of the ribosome without proper scientific support, Caetano-Anollés said. The most fundamental of these assumptions is that the part of the ribosome that is responsible for protein synthesis, the peptidyl transferase center (PTC) active site, is the most ancient.

In the new analysis, Caetano-Anollés and graduate student Ajith Harish (now a postdoctoral researcher at Lund University in Sweden) subjected the universal protein and RNA components of the ribosome to rigorous molecular analyses -- mining them for evolutionary information embedded in their structures. (They also analyzed the thermodynamic properties of the ribosomal RNAs.) They used this information to generate timelines of the evolutionary history of the ribosomal RNAs and proteins.

These two, independently generated "family trees" of ribosomal proteins and ribosomal RNAs showed "great congruence" with one another, Caetano-Anollés said. Proteins surrounding the PTC, for example, were as old as the ribosomal RNAs that form that site. In fact, the PTC appeared in evolution just after the two primary subunits that make up the ribosome came together, with RNA bridges forming between them to stabilize the association.

The timelines suggest that the PTC appeared well after other regions of the protein-RNA complex, Caetano-Anollés said. This strongly suggests, first, that proteins were around before ribosomal RNAs were recruited to help build them, and second, that the ribosomal RNAs were engaged in some other task before they picked up the role of aiding in protein synthesis, he said.

"This is the crucial piece of the puzzle," Caetano-Anollés said. "If the evolutionary build-up of ribosomal proteins and RNA and the interactions between them occurred gradually, step-by-step, the origin of the ribosome cannot be the product of an RNA world. Instead, it must be the product of a ribonucleoprotein world, an ancient world that resembles our own. It appears the basic building blocks of the machinery of the cell have always been the same from the beginning of life to the present: evolving and interacting proteins and RNA molecules."

"This is a very engaging and provocative article by one of the most innovative and productive researchers in the field of protein evolution," said University of California at San Diego research professor Russell Doolittle, who was not involved in the study. Doolittle remains puzzled, however, by "the notion that some early proteins were made before the evolution of the ribosome as a protein-manufacturing system." He wondered how -- if proteins were more ancient than the ribosomal machinery that today produces most of them -"the amino acid sequences of those early proteins were 'remembered' and incorporated into the new system."

Caetano-Anollés agreed that this is "a central, foundational question" that must be answered. "It requires understanding the boundaries of emergent biological functions during the very early stages of protein evolution," he said. However, he said, "the proteins that catalyze non-ribosomal protein synthesis -- a complex and apparently universal assembly-line process of the cell that does not involve RNA molecules and can still retain high levels of specificity -- are more ancient than ribosomal proteins. It is therefore likely that the ribosomes were not the first biological machines to synthesize proteins."

Read more at Science Daily

Two New Species of Horned Dinosaur Named

Two new horned dinosaurs have been named based on fossils collected from Alberta, Canada. The new species, Unescopceratops koppelhusae and Gryphoceratops morrisoni, are from the Leptoceratopsidae family of horned dinosaurs. The herbivores lived during the Late Cretaceous period between 75 to 83 million years ago. The specimens are described in research published in the Jan. 24, 2012, online issue of the journal Cretaceous Research.

"These dinosaurs fill important gaps in the evolutionary history of small-bodied horned dinosaurs that lack the large horns and frills of relatives like Triceratops from North America," said Michael Ryan, Ph.D., curator of vertebrate paleontology at The Cleveland Museum of Natural History, lead author on the research. "Although horned dinosaurs originated in Asia, our analysis suggests that leptoceratopsids radiated to North America and diversified here, since the new species, Gryphoceratops, is the earliest record of the group on this continent."

Unescoceratops koppelhusae lived approximately 75 million years ago. It measured about one to two meters (6.5 feet) in length and weighed less than 91 kilograms (200 pounds). It had a short frill extending from behind its head but did not have ornamentation on its skull. It had a parrot-like beak. Its teeth were lower and rounder than those of any other leptoceratopsid. In addition, its hatchet-shaped jaw had a distinct portion of bone that projected below the jaw like a small chin.

The lower left jaw fragment of Unescoceratops was discovered in 1995 in Dinosaur Provincial Park, a United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Site by Philip Currie, Ph.D., now of the University of Alberta. Originally described in 1998 by Ryan and Currie, the dinosaur was referred to as Leptoceratops. Subsequent research by Ryan and David Evans, Ph.D., of the Royal Ontario Museum in Toronto, Canada, determined the specimen was a new genus and species. The genus is named to honor the UNESCO World Heritage Site designation for the locality where the specimen was found and from the Greek "ceratops," which means "horned face." The species is named for Eva Koppelhus, Ph.D., a palynologist at the University of Alberta and wife of Currie.

Gryphoceratops morrisoni lived about 83 million years ago. It had a shorter and deeper jaw shape than any other leptoceratopsid. Researchers believe the individual was a full-grown adult. Based on unique characteristics of the jaw and its size, the researchers believe that Gryphoceratops was an adult that did not exceed one-half meter in length. This means it is the smallest adult-sized horned dinosaur in North America and one of the smallest adult-sized plant-eating dinosaurs known.

Lower right jaw fragments of Gryphoceratops were discovered in southern Alberta in 1950 by Levi Sternberg while he worked for the Royal Ontario Museum. The genus is named for "Gryphon," a mythological Greek figure with the body of a lion and the head of an eagle, which is a reference to the animal's beaked face. The species name honors Ian Morrison, a Royal Ontario Museum technician, who discovered how the bones fit together.

Second author Evans, associate curator of vertebrate palaeontology at the Royal Ontario Museum and assistant professor at the University of Toronto, said, "Small-bodied dinosaurs are typically poorly represented in the fossil record, which is why fragmentary remains like these new leptoceratopsids can make a big contribution to our understanding of dinosaur ecology and evolution."

Read more at Science Daily

Who Was St. Patrick?

How to celebrate St. Patrick's Day in the United States: Cover yourself in green (bonus points for shamrocks), put a smiling leprechaun cut-out on your front door, head to your local "Irish Pub" after work, get rowdy and wasted.

How to celebrate St. Patrick's Day in England: Eh, maybe pop down to the local pub for a nice pint.

How to celebrate St. Patrick's Day in Ireland: Go to church.

Those who recognize St. Patrick's Day celebrate it very differently depending on where they're from, and believe it or not, it's the United States that has turned the Emerald Isle's namesake tradition into a huge party scene, when its original intent was to be observed as a religious holiday.

For thousands of years, Irish Catholics have traditionally celebrated St. Patrick's Day by attending church in the morning and celebrating in the afternoon with a huge feast, honoring Ireland's patron saint. Even though March 17 falls in the middle of Lent when Catholics were forbidden to eat meat, this was waived in Ireland for feasting -- mostly on cabbage and Irish bacon, according to

Today, corned beef and cabbage is the traditional St. Patrick's Day meal, and in 2005, Americans consumed 2.4 billion pounds of cabbage, according to the U.S. Census Bureau.

But who was Saint Patrick? The truth is, much of his life is a mystery. One of the most famous legends of St. Patrick describes how he banished all snakes from the Emerald Isle into the ocean and they drowned. Philip M. Freeman, an expert in Celtic and classical studies at Washington University in St. Louis claims in his book, "St. Patrick of Ireland," that this legend is false.

What is known about St. Patrick is that he was born in England to wealthy parents near the end of the 4th century. At age 15, he was kidnapped by Irish pirates from his parents' estate in the Roman province of Britain, and sold into slavery in Ireland, where he spent six years in captivity, according to Freeman. After his escape, Patrick wrote in a letter of an "angel" speaking to him in a dream, telling him to become a missionary in Ireland, according to

After combing through two of Patrick's letters, Freeman confirms that Patrick attended training to become a priest in Ireland and was eventually made a bishop. He converted many of the Irish people from paganism to Christianity. St. Patrick is believed to have died on March 17, around 460 A.D., and many villagers across Ireland mourned his death on this day. From that, grew a celebration.

Like many other holidays, such as Halloween, St. Patrick's Day was recognized as a national holiday in the United States after thousands of Irish people immigrated to the country during the potato famine of the 1880s, bringing their traditions with them. Also like many other holidays, what began as small community affairs, St. Patrick's Day celebrations have exploded into full-on extravaganzas in the United States.

The first U.S. St. Patrick's Day parade took place in New York City on March 17, 1762, when Irish soldiers serving in the English military marched through the city. Now, over 100 cities across the country hold public festivities, according to the U.S. Census Bureau. Today, about 34.7 million Americans identify themselves as having Irish ancestry.

Read more at Discovery News

Why the Man in the Moon is Always 'Looking' at Earth

    "The man in the moon came down too soon,
    and asked his way to Norwich,
    They sent him south and he burnt his mouth
    By eating cold pease-porridge."

    -- Traditional nursery rhyme

It's human nature to see shapes and patterns all around us, and ascribe a meaning to what is actually just a random coincidence. The phenomenon is called pareidolia, and includes things like seeing the Virgin Mary in a piece of burnt toast, for example.

But some examples are more persistent than others -- like the Man in the Moon. It's not a real face, of course, just a quirk of how the dark areas (the lunar maria, or "seas") and lighter highlands of the lunar surface are arranged. Yet the illusion is powerful enough to have a Western mythology dating back thousands of years, inspiring all manner of nursery rhymes and literary references.

And there's some interesting physics at work here as well, at least according to a new paper in the journal Icarus. See, the Man in Moon is always staring at us here on Earth -- or, if you want to be all science-y about it, those particular features of the lunar surface always face Earth.

It happens because the moon is locked in what's known as a "synchronous orbit": for every orbit it completes around the Earth, the moon also rotates exactly one time. So we always see that face.

But it didn't necessarily have to be that way; why is this side of the moon, and not the other, the one that faces Earth? There had to be a 50/50 chance of it being one way or the other. Or so astronomers have thought -- until now.

Two Caltech astronomers, along with an Israeli colleague, think that there's a perfectly good explanation why the Man in the Moon always faces us -- and it's not due to the proverbial coin toss. Rather, Oded Aharanson, Peter Goldreich, and Re'em Sari propose that it's due to the fact that the Moon spun around its axis much faster in the past than it does today. And the rate at which it gradually slowed its pace could explain why it eventually became locked in the current orientation.

When the moon formed some four billion years ago, it was a blob of hot molten stuff. The Earth's gravitational pull stretched it a bit, elongating it like a football, and that shape stuck when the Moon cooled off. The Man in the Moon is at one of those oblong ends.

Back then -- about a couple billion years ago -- any inhabitants of Earth would have seen varying sides of the moon, not just the fixed face. But that relentless gravitational pull from Earth eventually slowed down the Moon's rate of spin on its axis, and tidal forces created yet another bulge, one that moved around in such a way that it always pointed toward Earth.

And this is where the physics starts to get interesting. Per the official press release:

    The bulge continued to point toward Earth as the moon rotated through it, causing the moon's interior to squish and flex as the bulge changed position. The internal friction from this flexing acted as a brake that slowed the moon's spinning until its rotation rate matched its revolution rate, when it settled into a synchronous orbit.

    In this way, as a result of Earth's gravity, the moon became locked into an orientation with its long axis pointing toward our planet.

So far, so good, but it still seems like a bit of a coin toss when it comes to which side of the moon faces Earth. The Caltech team ran a series of computer simulations, plugging in many different rates of slowing, and found they could "load" the coin however they wanted, so that either side of the moon would always face the Earth when it hit that locking point -- depending on that rotational energy dissipation rate.

Read more at Discovery News

Mar 12, 2012

World's Tallest Man Stops Growing

The world's tallest man appears to have stopped growing following treatment at the University of Virginia Medical Center, earning the medical center a mention in the 2012 Guinness World Records.

In May 2010, 8-foot-3-inch Sultan Kosen of Turkey made his first visit to UVA for treatment by endocrinologist Mary Lee Vance, MD. Kosen suffers from acromegaly, which is usually caused by a tumor in the pituitary gland. The tumor causes a large amount of growth hormone to be produced, which can lead to gigantism if the excess growth hormone is produced before puberty begins.

The condition can cause a range of health problems, Dr. Vance says. "His skeleton just can't support him," she says.

Advanced Treatments

Dr. Vance placed Kosen on a new medication that could potentially help control the production of growth hormone and stop his continued growth. Because Kosen's pituitary tumor had spread to areas of his brain where doctors could not safely perform open surgery, UVA neurosurgeon Jason Sheehan, MD, then performed Gamma Knife radiosurgery in August 2010.

Gamma Knife radiosurgery is a noninvasive procedure that delivers focused beams of radiation guided by MRI to a specific spot in a patient's body -- in this case, Kosen's pituitary tumor.

About three months ago, Kosen's doctors in Turkey told Dr. Sheehan that Kosen has stopped growing. "The treatments that we provided at the University of Virginia have stopped the production of his excess growth hormone and stopped the growth of the tumor itself," Dr. Sheehan says.

Stopping Growth, Saving a Life

Kosen's listing in the 2012 edition of Guinness World Records cites his treatment at UVA, though Dr. Vance and Dr. Sheehan are happiest that they were able to provide effective care.

"Treating someone 8 feet 3 inches tall is no different from treating someone 5 feet 10 inches tall," Dr. Vance says. "The important thing is to stop the production of the excess growth hormone."

Read more at Science Daily

3-D Printer With Nano-Precision

Printing three-dimensional objects with incredibly fine details is now possible using "two-photon lithography." With this technology, tiny structures on a nanometer scale can be fabricated. Researchers at the Vienna University of Technology (TU Vienna) have now made a major breakthrough in speeding up this printing technique: The high-precision-3D-printer at TU Vienna is orders of magnitude faster than similar devices. This opens up completely new areas of application, such as in medicine.

Setting a New World Record

The 3D printer uses a liquid resin, which is hardened at precisely the correct spots by a focused laser beam. The focal point of the laser beam is guided through the resin by movable mirrors and leaves behind a hardened line of solid polymer, just a few hundred nanometers wide. This fine resolution enables the creation of intricately structured sculptures as tiny as a grain of sand. "Until now, this technique used to be quite slow," says Professor Jürgen Stampfl from the Institute of Materials Science and Technology at the TU Vienna. "The printing speed used to be measured in millimeters per second -- our device can do five meters in one second." In two-photon lithography, this is a world record.

This amazing progress was made possible by combining several new ideas. "It was crucial to improve the steering mechanism of the mirrors," says Jan Torgersen (TU Vienna). The mirrors are continuously in motion during the printing process. The acceleration and deceleration-periods have to be tuned very precisely to achieve high-resolution results at a record-breaking speed.

Photoactive Molecules Harden the Resin

3D-printing is not all about mechanics -- chemists had a crucial role to play in this project too. "The resin contains molecules, which are activated by the laser light. They induce a chain reaction in other components of the resin, so-called monomers, and turn them into a solid," says Jan Torgersen. These initiator molecules are only activated if they absorb two photons of the laser beam at once -- and this only happens in the very center of the laser beam, where the intensity is highest. In contrast to conventional 3D-printing techniques, solid material can be created anywhere within the liquid resin rather than on top of the previously created layer only. Therefore, the working surface does not have to be specially prepared before the next layer can be produced, which saves a lot of time. A team of chemists led by Professor Robert Liska (TU Vienna) developed the suitable ingredients for this special resin.

Researchers all over the world are working on 3D printers today -- at universities as well as in industry. Because of the dramatically increased speed, much larger objects can now be created in a given period of time. This makes two-photon-lithography an interesting technique for industry.

Read more at Science Daily

Lost Da Vinci Found? Mona Lisa Paint Lends Clue

Researchers struggling to solve a longstanding Leonardo da Vinci mystery -- the fate of a lost masterpiece known as the "Battle of Anghiari -- have found intriguing traces of paint hidden behind a 5-inch-thick frescoed wall in Palazzo Vecchio, Florence's 14th-century city hall.

The color is consistent with that used by the Renaissance creator of the Mona Lisa, suggesting that Leonardo's artwork has remained hidden behind that frescoed wall for more than 500 years.

Known as the "Battle of Marciano," the mural was painted by the renowned 15th-century painter, architect and writer Giorgio Vasari (1511-1574) in the imposing Hall of the Five Hundred. The hall was a room built at the end of the 15th century to accommodate the meetings of the Florentine Council.

Right behind that wall could lie one of the biggest discoveries in the history of art, according to art diagnostic expert Maurizio Seracini, director of the Center of Interdisciplinary Science for Art, Architecture and Archaeology at the University of California, San Diego, who has been searching for the lost masterpiece since the 1970s.

Three months ago Seracini's team drilled six tiny holes into Vasari's fresco, inserted a 0.15-inch-wide probe and micro-cameras and collected samples of red, white, orange and black material.

Analysis with a scanning electron microscope revealed the black material had an unusual chemical makeup of manganese and iron.

The compound corresponds to the "black pigment found in brown glazes on Leonardo's 'Mona Lisa' and 'St John the Baptist,'" Seracini said on Monday at a press conference in the Hall of Five Hundred.

Red material, most likely red lacquer, was also found. The researchers said that this kind of material is unlikely to be present in an ordinary plastered wall. High definition endoscopic images also revealed a beige material which "could only have been applied by a paint brush," the researcher said.

"Evidence suggests we are searching in the right place," Seracini said.

"The Battle of Anghiari" has a mysterious history. It was conceived in 1503, when Leonardo and Michelangelo received twin commissions to paint on opposite walls of the Palazzo Vecchio.

Both murals were to represent historic Florentine victories, and the commissions reinforced the intense rivalry between the two artists.

While Michelangelo never got past a sketch of his "Battle of Cascina," Leonardo began to paint the "Battle of Anghiari" on June 6, 1505, when he was 53. The mural would celebrate the Florentines' victory over Milanese troops in 1440.

In his 1550 book "Lives of the Artists," Vasari said that Leonardo painted only a portion of the 12- by 15-foot fresco. It was a battle known as the "Fight for the Standard," which represented "the rage and fury both of the men and the horses," Vasari wrote.

He also said that Leonardo abandoned the project because of technical problems arising from his experimental mixing of oil paint and fresco.

Historians, however, have questioned Vasari's conclusion. Some speculated that he made up the story, and that the fresco actually was completed.

Hailed by Leonardo's contemporaries as his finest work, the "Battle of Anghiari" now survives in several preparatory drawings and sketches by the master himself and in a Rubens drawing which was inspired by an anonymous copy of the fresco.

Ten years after writing his account of the "Battle of Anghiari," Vasari was hired to modify the council room into the Hall of Five Hundred, a hall dedicated to the ruling Medici family.

In the course of this work, Leonardo's mural disappeared.

It wasn't the only artwork to dissolve. Working on the city-wide renovation plan devised by Duke Cosimo I to celebrate the Medici family, Vasari had to sacrifice masterpieces such as Masaccio's Trinity in the church of Santa Maria Novella.

Yet he did not destroy the work; he just bricked it over and added his own fresco, the "Madonna of the Rosary."

Masaccio's work remained obscured until 1861, when Vasari's wall was removed.

Read more at Discovery News

Earthlings Dazzled by Venus-Jupiter Close Encounter

The two brightest planets in the sky, Venus and Jupiter, will likely draw attention to the western sky as darkness falls this week.

Planetariums, observatories and perhaps even weather forecast offices might get a number of inquiries about what those "two bright lights in the sky" are.

On Monday evening (March 12) they'll appear to line up side-by-side, and on Tuesday evening (March 13), they will be separated by just 3 degrees (about the width of two fingers held out at arm's length), with Venus standing just above and to Jupiter's right.

Shining in a completely dark sky for more than two hours before finally disappearing beyond the west-southwest horizon after 10:30 p.m. local daylight time, this planetary pair may appear even more eerie when they're sitting just above the horizon as opposed to when they appear higher in the sky.

There are also three interesting aspects concerning this eye-catching configuration.

Eight Times Brighter

When the planets are closest, Venus will glow at magnitude -4.3, while Jupiter will shine at -2.1 on astronomers' magnitude scale in which lower numbers correspond to brighter objects (negative numbers suggest an extremely bright view).

So how much brighter than Jupiter will Venus look? You might think that Venus is 2.2 times brighter than Jupiter, but this would be wrong.  Here's why:

During the second century B.C., the Greek astronomer Hipparchus placed the naked-eye stars into six brightness categories. We still use his methodology today: The lower the figure of magnitude, the brighter the object.

Then in 1856, British astronomer Norman Pogson defined Hipparchus's magnitude scale mathematically, making it follow a logarithmic relationship, in which two objects that differ in brightness by five magnitudes differ in apparent brightness by a factor of exactly 100. In other words, an increase of one magnitude represents a brightness increase that is equal to 2.512.

So the brightness factor equals 2.512 raised to the power of the magnitude difference.  In the case of Venus and Jupiter, their 2.2 magnitude difference works out to a light ratio difference of 7.59. Thus, Venus will appear nearly eight times brighter than Jupiter. Check it out for yourself.

Rare Events

Contrary to popular belief, conjunctions between Venus and Jupiter are not rare events; in fact they occur on average about every 13 months. Interestingly, the sidereal revolution periods (that is, the time it takes them to make one full orbit relative to the stars) of Venus, Earth and Jupiter are, respectively, 224.7008, 365.2564, and 4332.5894 days.

So 39 such periods of Venus are virtually equal to 24 orbital periods of the Earth and 2 periods of Jupiter.  For this reason, circumstances involving specific conjunctions between Venus and Jupiter repeat under almost identical conditions after a time span of just over 24 years.

On March 5, 1988, Venus and Jupiter were in conjunction, with Venus passing 2.2 degrees north of Jupiter. A little more than 24 years later brings us to this week. On March 13, 2012, Venus will pass 3 degrees north of Jupiter.

Looking ahead, on March 22, 2036, these same two planets will come to conjunction once again, with Venus passing 4 degrees north of Jupiter.

Six Full Moons

While you're out on Tuesday (March 13) making sure Venus is about eight times brighter than Jupiter, try to also imagine that no less than six full moons can be lined up in the space between those planets. This is because the apparent width of the moon equals about 0.5 degrees, so certainly six moons should fit the 3-degree gap between the two planets.

And yet it doesn't seem possible when you're looking at them in the actual sky; the illusion is maddening.  You might think two or three moons maybe, but it seems impossible that six moons can be squeezed into the gap between the planets. And yet they can.

Interestingly, this strange illusion also extends to the "pretend universe" of the planetarium.

When the first star projectors were designed back in 1927, the moon and sun were made to appear to extend across 0.5 degrees as they would on the real sky.  But it was quickly discovered that they appeared too small to look realistic, although they were in actuality the correct angular size.

Read more at Discovery News

Mar 11, 2012

Thermonuclear Behavior of Unique Neutron Star Captured

A neutron star is the closest thing to a black hole that astronomers can observe directly, crushing half a million times more mass than Earth into a sphere no larger than a city. In October 2010, a neutron star near the center of our galaxy erupted with hundreds of X-ray bursts that were powered by a barrage of thermonuclear explosions on the star's surface. NASA's Rossi X-ray Timing Explorer (RXTE) captured the month-long fusillade in extreme detail. Using this data, an international team of astronomers has been able to bridge a long-standing gap between theory and observation.

"In a single month from this unique system, we have identified behavior not seen in observations of nearly 100 bursting neutron stars during the past 30 years," said Manuel Linares, a postdoctoral researcher at the Kavli Institute for Astrophysics and Space Research at the Massachusetts Institute of Technology in Cambridge. He led a study of the RXTE data that will be published in the March 20 issue of The Astrophysical Journal.

On Oct. 10, 2010, the European Space Agency's INTEGRAL satellite detected a transient X-ray source in the direction of Terzan 5, a globular star cluster about 25,000 light-years away toward the constellation Sagittarius. The object, dubbed IGR J17480-2446, is classed as a low-mass X-ray binary system, in which the neutron star orbits a star much like the sun and draws a stream of matter from it. As only the second bright X-ray source to be found in the cluster, Linares and his colleagues shortened its moniker to T5X2.

Three days after the source's discovery, RXTE targeted T5X2 and detected regular pulses in its emission, indicating that the object was a pulsar -- a type of neutron star that emits electromagnetic energy at periodic intervals. The object's powerful magnetic field directs infalling gas onto the star's magnetic poles, producing hot spots that rotate with the neutron star and give rise to X-ray pulses. At NASA's Goddard Space Flight Center in Greenbelt, Md., RXTE scientists Tod Strohmayer and Craig Markwardt showed that T5X2 spins at a sedate -- for neutron stars -- rate of 11 times a second. And because the pulsar's orbital motion imparts small but regular changes in the pulse frequency, they showed that the pulsar and its sun-like companion revolve around each other every 21 hours.

That same day, RXTE observed its first burst from the system: an intense spike in X-rays lasting nearly 3 minutes and caused by a thermonuclear explosion on the neutron star's surface. Ultimately, RXTE cataloged some 400 events like this between Oct. 13 and Nov. 19, with additional bursts observed by INTEGRAL and NASA's Swift and Chandra observatories. NASA decommissioned RXTE on Jan. 5, 2012.

In the T5X2 system, matter streams from the sun-like star to the neutron star, a process called accretion. Because a neutron star packs more than the sun's mass into a sphere between 10 and 15 miles across -- about the size of Manhattan or the District of Columbia -- its surface gravity is extremely high. The gas rains onto the pulsar's surface with incredible force and ultimately coats the neutron star in a layer of hydrogen and helium fuel. When the layer builds to a certain depth, the fuel undergoes a runaway thermonuclear reaction and explodes, creating intense X-ray spikes detected by RXTE and other spacecraft. The bigger the blast, the more intense its X-ray emission.

Models designed to explain these processes made one prediction that had never been confirmed by observation. At the highest rates of accretion, they said, the flow of fuel onto the neutron star can support continuous and stable thermonuclear reactions without building up and triggering episodic explosions.

At low rates of accretion, T5X2 displays the familiar X-ray pattern of fuel build-up and explosion: a strong spike of emission followed by a long lull as the fuel layer reforms. At higher accretion rates, where a greater volume of gas is falling onto the star, the character of the pattern changes: the emission spikes are smaller and occur more often.

Read more at Science Daily

A Cheap and Fully Optical Solution for Ultra-Fast Internet

Blisteringly fast Internet speeds, more robust connections and a big increase in network capacity at little extra cost, even in rural areas? It's the sort of fantasy that keeps telecommunication company executives and bandwidth-hungry Internet users awake at night... until now. Groundbreaking fibre-optic technology recently developed with EU-fundingis promising all those things and more.

A consortium of universities, research institutes, equipment vendors and one telecom operator joined forces in the 'Scalable advanced ring-based passive dense access network architecture' Sardana project to develop pioneering techniques to dramatically improve the scalability and robustness of the fibre-to-home networks that already serve millions of European internet users. Supported by EUR 2.6 million in research funding from the European Commission, the project not only demonstrated connection speeds of up to 10 Gigabits per second (Gbps), around 2,000 times faster than most Internet users experience today, but the researchers showed that such speeds can be achieved at relatively little extra cost using existing fibre infrastructure and off-the-shelf components.

Though still in the experimental stages, the fully optical technology, if deployed commercially, would mark a giant leap forward in fibre network performance, directly addressing one of the biggest challenges currently facing service providers and consumers.

According to some estimates, yearly global Internet traffic will need to be measured in Zettabytes (one trillion Gigabytes) within the next three years, a four-fold increase from today and the data equivalent of all the movies ever made passing through operators' networks every five minutes. Streaming video from sites such as YouTube and Netflix will account for most of the traffic, alongside more widespread use of similarly bandwidth-demanding video conferencing and telepresence applications.

European network operators have been warning in recent years that in order to meet this ever-rising demand for more bandwidth and capacity they will be forced to invest billions in new infrastructure and that the cost will have to be passed on to end users.

The Sardana researchers believe they have found a viable alternative. 'We are proposing a new access network architecture using fibre to the home that provides new functionalities and extended performance,' says Josep Prat, a researcher in the Optical Communications Group (GCO) at the Universitat Politècnica de Catalunya (UPC) and the scientific coordinator of the Sardana project.

Conventional fibre-to-home networks, also known as Passive Optical Networks (PONs), have a tree-like structure with the telephone exchange central office at their root. 'Passive' refers to their use of optical splitters which do not require additional power. From there a thick main trunk of cables spreads out into smaller branches to homes and businesses. Conventional tree PONs use Time Division Multiplexing (TDM), a multiplexing method inwhich signals are transferred apparently simultaneously as sub-channelsin one communication channel, but are actually physically taking turns on the channel. In practice, this means that a 5 Gbps connection at the central office can turn into a 30 Mbps downstream connection by the timeit reaches someone's home, with upstream bandwidth usually a mere fraction of that.

From trees to rings

The Sardana researchers are proposing a different and totally new approach, enablingnot only much faster connections, but more capacity and robustness. Instead of a single big tree, they are proposing multiple smaller trees branching out to end users from a main ring. The ring transmits signals bidirectionally from the central office using Wave Division Multiplexing(WDM), a multiplexing technology that enables different signals to be carried simultaneously on the same optical fibre by using different wavelengths of laser light. At Remote Nodes along the ring, the signals split off onto single fibre trees to homes and businesses using TDM technology.

The bidirectional ring approach improves network robustness because if the cable is broken at any location on the WDM ring the signal will still reach end users from the other direction. It also results in massive increases in connection speed.

'Using WDM on the ring means we can multiply bandwidth by 40 wavelengths so individual users can enjoy 1 Gbps: not just in one direction, but in both directions, both upstream and downstream,' Prof. Prat says. 'This could open the door to entirely new applications that are simply not possible today, such as high definition video conferencing.'

Laboratory tests by Finnish equipment vendor Tellabs were followed by a field trial near France Telecom-Orange's facilities in Brittany, France,and a demonstration at the Fibre to the Home Council (FTTH) in Milan. Using emulation technology combined with real-world infrastructure, the tests showed that the network is able to serve between 1,000 and 4,000 users within 20 kilometres of the main ring with symmetric internet connections at speeds of around 300 Mbps. Separately, the researchers also demonstrated that the technology could be used to transmit optical signals up to 100 kilometres from the central office in order to provideup to 250 homes with asymmetrical 10 Gbps downstream and 2.5 Gbps upstream connections. Crucially, from a commercial point of view, such improvements can be achieved at little extra cost and the technology maintains network transparency, supporting the use of the same infrastructure by multiple service providers.

Read more at Science Daily

In Recognizing Faces, the Whole Is Not Greater Than the Sum of Its Parts

How do we recognize a face? To date, most research has answered "holistically": We look at all the features -- eyes, nose, mouth -- simultaneously and, perceiving the relationships among them, gain an advantage over taking in each feature individually. Now a new study overturns this theory. The researchers -- Jason M. Gold and Patrick J. Mundy of the Indiana University and Bosco S. Tjan of the University of California Los Angeles -- found that people's performance in recognizing a whole face is no better than their performance with each individual feature shown alone. "Surprisingly, the whole was not greater than the sum of its parts," says Gold. The findings appear in the journal Psychological Science, which is published by the Association for Psychological Science.

To predict each participant's best possible performance in putting together the individual features, the investigators used a theoretical model called an "optimal Bayesian integrator" (OBI). The OBI measures someone's success in perceiving a series of sources of information -- in this case, facial features -- and combines them as if they were using the sources together just as they would when perceiving them one by one. Their score recognizing the combination of features (the whole face) should equal the sum of the individual-feature scores. If the whole-face performance exceeds this sum, it implies that the relationships among the features enhanced the information processing -- that is, "holistic" facial recognition exists.

In the first experiment participants were shown fuzzy images of three male and three female faces. Then either one feature -- a left or right eye, nose, or mouth -- or all four in proper face-like relationships appeared on the screen. That image would disappear and, if they saw an eye, all six eyes would appear; if a whole face, six whole faces. The participants clicked on the feature or face they'd just seen. In a second experiment, the whole-face images were superimposed on face-shaped ovals -- in case such context helps holistic recognition, as is often claimed. In both experiments, participants' performance with the whole faces was no better than with the isolated features -- and no better than the OBI -- indicating that the facial features were not processed holistically when shown in combination.

"The OBI offers a clearly defined mathematical framework for studying what historically has been a rather loosely defined set of concepts," says Gold.

Read more at Science Daily

America, the Beautiful (And Nutty): A Skeptic’s Lament

Almost one-third of Americans believe the ancient Mayan prediction of global calamity this December are “somewhat true,” according to a recent National Geographic poll. The prediction is based on a huge stone calendar wheel but exact nature of the disaster — already the subject of major motion pictures and fodder for a Super Bowl ad of remarkably black humor — is an open question. Perhaps an apocalypse will be sparked by expensive gasoline or another Charlie Sheen tantrum. Or maybe those early Mexicans just ran out of stone.

I’m a magician by profession, now retired and dedicated to communicating the facts about the so-called paranormal and the occult, and the supernatural people, claims, and stories that abound. My organization — The James Randi Educational Foundation — serves as a source of information about what I call “woo woo.” We work with a large number scientists, statisticians, and experts to evaluate and debunk for the benefit of the media, scientists, writers, students, and the merely curious.

Our efforts have brought JREF to the forefront of the world skeptical movement, following in the footsteps of Carl Sagan, Isaac Asimov, Martin Gardner, Richard Feynman, Sir Arthur C. Clarke, and so many others — and I’m proud to say that I knew them all well.

We do this day in and day out. And humans aren’t born crazy. But somehow nonsense science has what seems like a permanent foothold in our culture.

Not all dissonance is perilous. The general public accepts some obviously false beliefs: whales are fish, we only use about 10% of our brains, “free energy” is just around the corner for us all.

Wrong, but not nuts.

Now consider this: Some 70% of Americans believe in some aspect of the paranormal — ESP, devils, ghosts, homeopathy, and spiritual healing. More than 25% believe there are humans who can “psychically” predict the future. About 20% believe it’s possible to talk to dead people (and that the dead talk back).

In other words, a sizable portion of the U.S. population accepts as a given that an unseen world of magical paranormal power exists, and all that remains is to discover how to take advantage of it. Some pay handsomely in that vain — I mean this in both senses of the word — pursuit.

Personality traits, psychological motivation, flawed cognition, emotional instability, local demographics, social influences — all these could contribute to what might be called Lack of Reason Syndrome. Let’s add as well: basic ignorance. But experimental psychology has yet to fully explain why essentially rational beings seem to need to be at least a little irrational.

But we humans are gullible and not terribly perceptive. In my world these handicaps, and an audience’s innate desire to believe, combine to, well, make magic. The trick is really over before it begins because the magician has, without your knowledge, manipulated your behavior to suit his needs.

That’s just good fun. The stakes in the real world are much higher.

While the science establishment hasn’t always been vociferous enough about paranormal silliness and schemes, make no mistake: my respect for real science knows no bounds. Yes, my work inescapably points out where science has, for one reason or another, sometimes failed to police its own. But I believe — I know — that science is a glorious, righteous pursuit.

And so I begin my work here at Wired Opinion with a direct, firm, personal statement of my own convictions, derived from 60+ years of close association with dedicated scientists and the responsible media:

    Those very popular mythical beasties — ESP, psychokinesis, prophecy, etc. — don’t exist.
    Homeopathy is a dangerous farce.
    Faith-healing is a deadly joke.
    Perpetual motion is a juvenile dream.
    Uri Geller is a 4-trick magician.
    The dead don’t talk to anyone.
    Religion is an ancient notion we need to get over.


Having identified the illness, the question is, how able is the patient to participate in a cure? Figuring that out is part science, and part art.

The advertising industry knows this. They know that consumers will often respond to pricing tricks that do not bear up under the barest scrutiny. A 2009 Cornell University study found that we tend to interpret precise numbers that are bigger than rounded numbers as being lower: participants, for example, incorrectly judged $395,425 to be smaller than $395,000.

The skeptical mind boggles …

Read more at Wired Science