Fungi, Feces Show Comet Didn't Kill Ice Age Mammals?

A microscope picture shows the spongy texture of a carbon spherule.

Tiny balls of fungus and feces may disprove the theory that a huge space rock exploded over North America about 12,900 years ago, triggering a thousand-year cold snap, according to a new study.

The ancient temperature drop, called the Younger Dryas, has been well documented in the geologic record, including soil and ice core samples.

The cool-down also coincides with the extinction of mammoths and other Ice Age mammals in North America, and it's thought to have spurred our hunter-gatherer ancestors in the Middle East to adopt an agricultural lifestyle.

But the theory that a comet or asteroid explosion is behind the cooling event is wrong, according to study leader Andrew C. Scott, a paleobotanist at Royal Holloway University in London.

For years proponents of the impact theory have cited tiny spherules of carbon found in a layer of charred sediment throughout North America that dates to the Younger Dryas period.

According to the theory, these spherules are organic matter subjected to intense heat after debris from an exploded meteor rained down on Earth, sparking massive wildfires.

The new research, however, detected carbon spherules in soil layers from before, during, and after the Younger Dryas, making it hard to argue that the particles are products of a sudden impact.

What's more, Scott's team found that most of the spherules are similar to tightly packed balls of fungus found in modern soils that have been exposed to low to moderate heat during wildfires. Plant and soil fungi are known to create these balls of material to help them survive extreme conditions.

Other elongated forms of the spherules match modern fecal pellets from insects.

"All these particles are of natural biological origin and are not related to either intense wildfires or cosmic impacts," Scott said in an email.

"The press and public are very interested in catastrophic explanations," he added. "But it is important that when evidence stacks up to show the theory does not work, then it should be abandoned."

What About the Nanodiamonds?

In fact, most experts acknowledge that carbon spherules are found throughout the geological record, including biological forms associated with wildfires, said James Kennett, an emeritus geologist at the University of California, Santa Barbara, who supports the cosmic-impact hypothesis.

However, the spherules are not often found in large quantities, he said, and there is "a peak in carbon spherules at the Younger Dryas boundary."

What's more, those spherules are found alongside microscopic diamonds, or nanodiamonds, which often form under the conditions caused by extraterrestrial impacts.

The new study does not report evidence of nanodiamonds, Kennett noted, which is expected, since the team wasn't directly looking for them.

"So their [reported] data is consistent," Kennett said.

Study leader Scott said that his team has studied the nanodiamond issue, but he's not yet able to discuss the results.

He did, however, hint that the particles might not be nanodiamonds at all: Fungal spores the team examined have similar microscopic features.

And, Scott said, "obviously [spores] are not nanodiamonds."

The carbon spherule study has been accepted for publication in the journal Geophysical Research Letters.

Researchers Create Self-Assembling Nanodevices That Move and Change Shape on Demand

By emulating nature's design principles, a team at Harvard's Wyss Institute for Biologically Inspired Engineering, Harvard Medical School and Dana-Farber Cancer Institute has created nanodevices made of DNA that self-assemble and can be programmed to move and change shape on demand. In contrast to existing nanotechnologies, these programmable nanodevices are highly suitable for medical applications because DNA is both biocompatible and biodegradable.
The work appears in the June 20 advance online Nature Nanotechnology.

Built at the scale of one billionth of a meter, each device is made of a circular, single-stranded DNA molecule that, once it has been mixed together with many short pieces of complementary DNA, self-assembles into a predetermined 3D structure. Double helices fold up into larger, rigid linear struts that connect by intervening single-stranded DNA. These single strands of DNA pull the struts up into a 3D form -- much like tethers pull tent poles up to form a tent. The structure's strength and stability result from the way it distributes and balances the counteracting forces of tension and compression.

This architectural principle -- known as tensegrity -- has been the focus of artists and architects for many years, but it also exists throughout nature. In the human body, for example, bones serve as compression struts, with muscles, tendons and ligaments acting as tension bearers that enable us to stand up against gravity. The same principle governs how cells control their shape at the microscale.

"This new self-assembly based nanofabrication technology could lead to nanoscale medical devices and drug delivery systems, such as virus mimics that introduce drugs directly into diseased cells," said co-investigator and Wyss Institute director Don Ingber. A nanodevice that can spring open in response to a chemical or mechanical signal could ensure that drugs not only arrive at the intended target but are also released when and where desired.

Further, nanoscopic tensegrity devices could one day reprogram human stem cells to regenerate injured organs. Stem cells respond differently depending on the forces around them. For instance, a stiff extracellular matrix -- the biological glue surrounding cells -- fabricated to mimic the consistency of bone signals stem cells to become bone, while a soupy matrix closer to the consistency of brain tissue signals the growth of neurons. Tensegrity nanodevices "might help us to tune and change the stiffness of extracellular matrices in tissue engineering someday," said first author Tim Liedl, who is now a professor at Ludwig-Maximilians-Universität in Munich.

"These little Swiss Army knives can help us make all kinds of things that could be useful for advanced drug delivery and regenerative medicine," said lead investigator William Shih, Wyss core faculty member and associate professor of biological chemistry and molecular pharmacology at HMS and Dana-Farber Cancer Institute. "We also have a handy biological DNA Xerox machine that nature evolved for us," making these devices easy to manufacture.

This new capability "is a welcome element in the structural DNA nanotechnology toolbox," said Ned Seeman, professor of chemistry at New York University.

This research was funded by the Wyss Institute for Biologically Inspired Engineering at Harvard University, National Institutes of Health, Deutscher Akademischer Austauschdienst Fellowship, Swedish Science Council Fellowship and Claudia Adams Barr Program Investigator award.

World's First Plastic Antibodies in Live Organisms: Stop Spread of Bee Venom in Mice

UC Irvine researchers have developed the first "plastic antibodies" successfully employed in live organisms -- stopping the spread of bee venom through the bloodstream of mice.
Tiny polymeric particles -- just 1/50,000th the width of a human hair -- were designed to match and encase melittin, a peptide in bee venom that causes cells to rupture, releasing their contents. Large quantities of melittin can lead to organ failure and death.

The polymer nanoparticles were prepared by "molecular imprinting" a technique similar to plaster casting: UCI chemistry professor Kenneth Shea and project scientist Yu Hoshino linked melittin with small molecules called monomers, solidifying the two into a network of long polymer chains. After the plastic hardened, they removed the melittin, leaving nanoparticles with minuscule melittin-shaped holes.

When injected into mice given high doses of melittin, these precisely imprinted nanoparticles enveloped the matching melittin molecules, "capturing" them before they could disperse and wreak havoc -- greatly reducing deaths among the rodents.

"Never before have synthetic antibodies been shown to effectively function in the bloodstream of living animals," Shea says. "This technique could be utilized to make plastic nanoparticles designed to fight more lethal toxins and pathogens."

Takashi Kodama of Stanford University and Hiroyuki Koide, Takeo Urakami, Hiroaki Kanazawa and Naoto Oku of Japan's University of Shizuoka also contributed to the study, published recently in the Journal of the American Chemical Society.

Unlike natural antibodies produced by live organisms and harvested for medical use, synthetic antibodies can be created in laboratories at a lower cost and have a longer shelf life.

"The bloodstream includes a sea of competing molecules -- such as proteins, peptides and cells -- and presents considerable challenges for the design of nanoparticles," Shea says. "The success of this experiment demonstrates that these challenges can be overcome."

Scientists Discover Heavenly Solar Music

Musical sounds created by longitudinal vibrations within the Sun's atmosphere, have been recorded and accurately studied for the first time by experts at the University of Sheffield, shedding light on the Sun's magnetic atmosphere.
Using state-of-the-art mathematical theory combined with satellite observations, a team of solar physicists from the University have captured the music on tape and revealed the harmonious sounds are caused by the movement of giant magnetic loops in the solar corona -- the outermost, mysterious, and least understood layer of the Sun's atmosphere. Most importantly, the team studied how this sound is decaying, giving an unprecedented insight into the physics of the solar corona.

High-resolution images taken by a number of satellites show that the solar corona is filled with large banana-shaped magnetic structures known as coronal loops. It is thought that these giant magnetic loops, some of them over a few 100,000 km long, play a fundamental role in governing the physics of the corona and are responsible for huge atmospheric explosions that occur in the atmosphere, known as solar flares.

These giant coronal loops have also been observed to undergo periodic (oscillatory) motion, which can be thought of as someone plucking a guitar string (transversal oscillations) or blowing the wind-pipe instrument (longitudinal oscillations). With the length and thickness of the string fixed, the pitch of the note is determined by the tension of the string and the tone is made up of the harmonics of the modes of oscillation.

In this sense, the solar atmosphere is constantly pervaded by the music of the coronal loops. The coronal music also provides scientists with a unique and unprecedented tool to study the magnetic solar atmosphere, as the motion of these loops is determined by their local surroundings. This technique is known as solar magneto-seismology and is very similar to the seismology methods used by geologists studying earthquakes.

Studying this magnetic solar atmosphere will help the team, which is headed-up by Professor Robertus von Fáy-Siebenbürgen and includes postgraduate student Richard Morton and postdoctoral research associate Dr Youra Taroyan, all from the Dept of Applied Mathematics, make further breakthroughs into understanding one of the key and central unresolved problems of modern astrophysics, i.e. the heating of solar and tellar coronal plasmas, and reveal the underlying physical processes: Are there millions of localised magnetic explosions releasing the energy necessary to maintain the corona at millions of degrees or is the physics related to the numerous waves propagating from the internal regions of the Sun toward its outer regions, reaching even space around the Earth's atmosphere.

The discovery was presented by the University experts to an audience of MPs both from the House of Commons and the House of Lords at the House of Commons Marquee, as well as and senior scientists representing prestigious institutions such as the Royal Society, after being selected by the Parliamentary and Scientific Committee.

The next step for the team will be to develop cutting edge numerical modelling that will be able to give further insight into the sub-resolution properties of coronal loops, i.e. on spatial scales that are not even observable with the latest high-resolution satellites available to scientist.

This is the second solar related breakthrough made by experts at the University. The way in which the solar corona is heated to temperatures of over a million degrees had, until recently, remained a long-standing puzzle of solar and space physics, as this region of the sun is even further away from the centre of energy production than the underlying solar surface. However Professor von Fáy-Siebenbürgen and his team last month solved this enigma and revealed that Transition Region Quakes -- described by the experts as 'mega-tsunamis' -- power the lower base of the solar corona.

The news comes as the University of Sheffield launches a unique venture entitled Project Sunshine, led by the Faculty of Science. The Project aims to unite scientists across the traditional boundaries in both the pure and applied sciences to harness the power of the sun and tackle the biggest challenge facing the world today: meeting the increasing food and energy needs of the world´s population in the context of an uncertain climate and global environment change. It is hoped that Project Sunshine will change the way scientists think and work and become the inspiration for a new generation of scientists focused on solving the world´s problems.

Professor Robertus von Fáy-Siebenbürgen from the University of Sheffield's Department of Applied Mathematics and Head of SP2RC, said: "The results of our latest coronal research, presented in the Parliament at Westminster, allow us to gain a fundamentally new insight into the fascinating but at the same time very mysterious solar atmosphere. I'm most proud to have such talented young scientists within my research group and department. The invitation by SET for Britain and our collaborative research efforts clearly demonstrate our international leadership position in the field of solar physics."

A video of the solar music is available on YouTube at the following URL: http://www.youtube.com/watch?v=ZbIffp40U8w

Hubble Captures Bubbles and Baby Stars

A spectacular new NASA/ESA Hubble Space Telescope image -- one of the largest ever released of a star-forming region -- highlights N11, part of a complex network of gas clouds and star clusters within our neighbouring galaxy, the Large Magellanic Cloud. This region of energetic star formation is one of the most active in the nearby Universe.
The Large Magellanic Cloud contains many bright bubbles of glowing gas. One of the largest and most spectacular has the name LHA 120-N 11, from its listing in a catalogue compiled by the American astronomer and astronaut Karl Henize in 1956, and is informally known as N11. Close up, the billowing pink clouds of glowing gas make N11 resemble a puffy swirl of fairground candy floss. From further away, its distinctive overall shape led some observers to nickname it the Bean Nebula. The dramatic and colourful features visible in the nebula are the telltale signs of star formation. N11 is a well-studied region that extends over 1000 light-years. It is the second largest star-forming region within the Large Magellanic Cloud and has produced some of the most massive stars known.

It is the process of star formation that gives N11 its distinctive look. Three successive generations of stars, each of which formed further away from the centre of the nebula than the last, have created shells of gas and dust. These shells were blown away from the newborn stars in the turmoil of their energetic birth and early life, creating the ring shapes so prominent in this image.

Beans are not the only terrestrial shapes to be found in this spectacular high resolution image from the NASA/ESA Hubble Space Telescope. In the upper left is the red bloom of nebula LHA 120-N 11A. Its rose-like petals of gas and dust are illuminated from within, thanks to the radiation from the massive hot stars at its centre. N11A is relatively compact and dense and is the site of the most recent burst of star development in the region.

Other star clusters abound in N11, including NGC 1761 at the bottom of the image, which is a group of massive hot young stars busily pouring intense ultraviolet radiation out into space. Although it is much smaller than our own galaxy, the Large Magellanic Cloud is a very vigorous region of star formation. Studying these stellar nurseries helps astronomers understand a lot more about how stars are born and their ultimate development and lifespan.

Both the Large Magellanic Cloud and its small companion, the Small Magellanic Cloud, are easily seen with the unaided eye and have always been familiar to people living in the southern hemisphere. The credit for bringing these galaxies to the attention of Europeans is usually given to Portuguese explorer Fernando de Magellan and his crew, who viewed it on their 1519 sea voyage. However, the Persian astronomer Abd Al-Rahman Al Sufi and the Italian explorer Amerigo Vespucci recorded the Large Magellanic Cloud in 964 and 1503 respectively.

Summer Solstice 2010: Why It's the First Day of Summer

People stretch their hands toward the sun during a summer solstice 2010 celebration at Stonehenge.

Why summer starts today, and why it's the longest day of the year—but not the hottest.

The first day of summer officially kicks off today at 7:28 a.m. ET, the beginning of the summer solstice and the longest day of the year—at least in the Northern Hemisphere.


The summer solstice is a result of the Earth's north-south axis being tilted 23.5 degrees relative to the sun. The tilt causes different amounts of sunlight to reach different regions of the planet.

Today the North Pole is tipped closer to the sun than on any other day of 2010. The opposite holds true for the Southern Hemisphere, for which today is the winter solstice, the shortest day of the year.

As a result, at high noon on the first day of summer, the sun appears at its highest point in the sky—its most directly overhead position—in the Northern Hemisphere.

That doesn't mean the sun will be exactly overhead at noon for everyone, said James Bell, an astronomer at Cornell University in New York State.

It depends on the viewer's latitude—the sun is only shining down directly overhead at noon at the Tropic of Cancer. "It's still at a low angle if you're up in Alaska," Bell explained.

No matter where you are in the Northern Hemisphere, the path of the sun across the sky—which rises in the lead-up to the first day of summer, then begins descending over the rest of the summer—seems not to change for the few days before and after the summer solstice.

In reality, the sun's position is still changing, but at a slower rate.

Summer Solstice Wobbles Around the Calendar

While the June solstice generally occurs on the same day every year, the date does change every once in a while. For example, in 2008, the summer solstice occurred on June 20.

This date shifting is a result of the discrepancy between a human calendar year—which is usually counted as 365 days—and an astronomical year, which is 365.25 days.

Our leap year system—which adds an extra day to the calendar every four years—ensures our calendars are accurate, but it also causes the solstice date to flop around a bit.

"It's nothing astronomical changing. What's changing is the human side of it," Bell said.

Solstice Is Longest Day of the Year—Not Hottest

On the summer solstice, the Northern Hemisphere receives more sunlight than on any other day of the year, but that doesn't mean the first day of summer is also the hottest day of summer.

Earth's oceans and atmosphere act like heat sinks, absorbing and reradiating the sun's rays over time. So even though the planet is absorbing lots of sunlight on the summer solstice, it takes several weeks to release it. As a result, the hottest days of summer usually occur in July or August.

"If you think about turning up an oven—it takes it a long time to heat up," explained Robert Howell, an astronomer at the University of Wyoming. "And after you turn it off, it takes a while for it to cool down. It's the same with the Earth."

First Day of Summer Sparked Ancient Celebrations

The summer solstice is recognized and often celebrated in many cultures around the world, in both the past and present.

The ancient Egyptians, for example, built the Great Pyramids so that the solstice sunset, when viewed from the Sphinx, sets precisely between two of the Pyramids.

The Inca of South America celebrated the summer solstice with a ceremony called Inti Raymi, which included food offerings and sacrifices of animals and maybe even people. (See a picture of an Inca summer solstice festival.)



And perhaps most famously, Stonehenge in the United Kingdom has been associated with the winter and summer solstices for about 5,000 years.

Observers in the center of the standing stones can watch the summer solstice sun rise over the Heel Stone, which stands just outside Stonehenge's stone circles.

For many of the ancients, though, the summer solstice wasn't just an excuse to party or pray—it was essential to their well-being.

Associated with agriculture, the summer solstice was a reminder that a turning point in the growing season had been reached.

"The calendar was very important—much more important than it is now," said Ricky Patterson, an astronomer at the University of Virginia. "People wanted to know what was going to happen so that they could be ready."

Spectacular Aurora Ribbon Photographed by Astronaut : Big Pic

June 21, 2010 -- This spectacular photograph shows a snaking aurora over the southern hemisphere as the International Space Station (ISS) orbited overhead. It occurred during a geomagnetic storm, likely caused by a coronal mass ejection (CME) slamming into our planet's magnetosphere.

Remote-Control Tron Legacy Light Cycle Defies Gravity

NEW YORK — A new remote-control light cycle toy scales walls just like the sci-fi vehicles do in the upcoming film Tron Legacy.

“In the movie, the light cycles drive in 3-D on the walls, so we wanted to re-create that,” said Chris Heatherly, vice president of toys and electronics for Disney Consumer Products, at a press event here Monday showing off the company’s new line of Tron-inspired toys, games and gear.

Battle of the Bugs Leaves Humans as Collateral Damage

It's a tragedy of war that innocent bystanders often get caught in the crossfire. But now scientists at the University of Pennsylvania and the University of Oxford have shown how a battle for survival at a microscopic level could leave humans as the unlikely victims.
In work funded by the US Public Health Service and the Wellcome Trust, the researchers have found a possible explanation for why some bacteria turn nasty, even at great risk to their own survival.

The body is home to a wide range of bacteria which in the vast majority of cases exist quietly, causing no harm. Sometimes, a bacterium will evolve properties which are potentially deadly to its human host. But evolution comes at a cost and this presents a paradox: why should it harm its host when this could result in the demise of the bacteria themselves?

"For many microbes, living in harmony with their host is the best option, so why do some suddenly turn nasty?" asks Dr Sam Brown, a Wellcome Trust Research Career Development Fellow at the University of Oxford. "Sometimes the answer is obvious -- for example, the cold virus makes its host sneeze, helping it spread wider. But for other bacteria and viruses, which do not normally cause disease, the reason isn't at all clear."

In a study published June 17 in Current Biology, scientists have modelled in mice how a commonly-found bacterium known as Streptococcus pneumoniae interacts with other bacteria, showing that competition for space between rival bacteria can cause deadlier forms of bacteria to evolve. S. pneumoniae usually exists in the nasal passage, where it sits quietly: as many as two in five people in some countries will carry the bug without being aware of it.

When S. pneumoniae is forced to share space with Haemophilus influenzae, another common and ordinarily asymptomatic bacterium, the two begin a tussle for space. But H. influenzae has an extra trick up its sleeve, calling on our immune system to help get rid of its competitor by recruiting white blood cells called neutrophils, which surround and attack the S. pneumoniae bacteria.

"Many bacteria are not a problem to our immune system, so can be left alone," explains Dr. Lysenko. "But the H. influenzae bacteria stir up trouble, saying to the body, 'S. pneumoniae are bad guys -- beat them up'. The neutrophils respond, attacking the innocent bacteria and thus helping H. influenzae to survive."

Many strains of S. pneumoniae exist, each coated with a thick sugar capsule. In some strains, the capsule is particularly protective, and appears to act as armour against the host's immune response. This allows the bacterium to enter the blood stream where it can go on to replicate and cause serious diseases such as pneumonia, bacteraemia (blood infection), septicaemia and meningitis.

The researchers tested different combinations of three bacteria -- two pneumococcal strains (armoured and un-armoured), and H. influenzae. They found that when a sufficient amount of H. influenzae was present, the more virulent, armoured strain of S. pneumoniae began to out-compete its rivals: its thick sugar coating was allowing it to escape attack from the neutrophils, but this property also made it more deadly when it entered the blood stream.

Dr Brown concludes: "Creating a new armour is costly to S. pneumoniae in terms of the energy expended to make it, but it means the bacterium wins the battle with H. influenzae. However, it also means that if S. pneumoniae enters the blood stream, the immune system is unable to stop its rampant progress. Our bodies are unable to cope and the armoured bug could pay the ultimate price: death to its host and death to itself."

According to Dr Jeff Weiser from the University of Pennsylvania School of Medicine, Philadelphia, the results could have implications for the development of new treatments and vaccines against infection.

"Our study demonstrates the complex interactions among the many microbial species that live in our bodies," he says. "Usage of antibiotics and vaccines is increasingly influencing these relationships, potentially tipping the outcome of the battle between competing microbes. Our ongoing war on infectious diseases should consider the effects of microbes on one another."

Super-Complex Organic Molecules Found in Interstellar Space

A team of scientists from the Instituto Astrofísica de Canarias (IAC) and the University of Texas has succeeded in identifying one of the most complex organic molecules yet found in the material between the stars, the so-called interstellar medium. The discovery of anthracene could help resolve a decades-old astrophysical mystery concerning the production of organic molecules in space.

The researchers report their findings in the journal Monthly Notices of the Royal Astronomical Society.

'We have detected the presence of anthracene molecules in a dense cloud in the direction of the star Cernis 52 in Perseus, about 700 light years from the Sun,' explains Susana Iglesias Groth, the IAC researcher heading the study.

In her opinion, the next step is to investigate the presence of amino acids. Molecules like anthracene are prebiotic, so when they are subjected to ultraviolet radiation and combined with water and ammonia, they could produce amino acids and other compounds essential for the development of life

'Two years ago,' says Iglesias, 'we found proof of the existence of another organic molecule, naphthalene, in the same place, so everything indicates that we have discovered a star formation region rich in prebiotic chemistry.' Until now, anthracene had been detected only in meteorites and never in the interstellar medium. Oxidized forms of this molecule are common in living systems and are biochemically active. On our planet, oxidized anthracene is a basic component of aloe and has anti-inflammatory properties.

The new finding suggests that a good part of the key components in terrestrial prebiotic chemistry could be present in interstellar matter.

Since the 1980s, hundreds of bands found in the spectrum of the interstellar medium, known as diffuse spectroscopic bands, have been known to be associated with interstellar matter, but their origin has not been identified until now. This discovery indicates that they could result from molecular forms based on anthracene or naphthalene. Since they are widely distributed in interstellar space, they might have played a key role in the production of many of the organic molecules present at the time of the formation of the Solar System.

The results are based on observations carried out at the William Herschel Telescope at Roque de los Muchachos Observatory on La Palma in the Canary Islands and with the Hobby-Eberly Telescope in Texas in the United States.

3.6 Million-Year-Old Relative of 'Lucy' Discovered: Early Hominid Skeleton Confirms Human-Like Walking Is Ancient

Meet "Lucy's" Great-Grandfather. Cleveland Museum of Natural History Curator and Head of Physical Anthropology Dr. Yohnannes Haile-Selassie led an international team that discovered and analyzed a 3.6 million-year-old partial skeleton found in Ethiopia. The early hominid is 400,000 years older than the famous "Lucy" skeleton and is significantly larger in size. Research on the new specimen reveals that advanced human-like, upright walking occurred much earlier in the evolutionary timeline than previously thought.
Haile-Selassie is the first author of the initial analysis of the specimen, which will be published in the online early edition of the Proceedings of the National Academy of Sciences during the week of June 21, 2010.

The partial skeleton belongs to "Lucy's" species, Australopithecus afarensis. It was found in the Woranso-Mille area of Ethiopia's Afar region by a team led by Haile-Selassie that excavated of the skeleton over five years following the discovery in 2005 of the lower arm bone. The team recovered the most complete clavicle and one of the most complete shoulder blades ever found in the human fossil record. A significant portion of the rib cage was also found.

The specimen was nicknamed "Kadanuumuu" (kah-dah-nuu-muu) by the authors. This means "big man" in the Afar language and reflects its large size. The male hominid stood between 5 to 5 ½ feet tall, while "Lucy" stood only 3 ½ feet tall.

"This individual was fully bipedal and had the ability to walk almost like modern humans," said Haile-Selassie. "As a result of this discovery, we can now confidently say that 'Lucy' and her relatives were almost as proficient walking on two legs as we are, and that the elongation of our legs came earlier in our evolution that previously thought."

He explained, "All of our understanding of Australopithecus afarenis' locomotion was dependent on 'Lucy.' Because she was an exceptionally small female with absolutely short legs, this gave some researchers the impression that she was not fully adapted to upright walking. This new skeleton falsifies that impression because if 'Lucy's' frame had been as large as this specimen, her legs would also have been proportionally longer."

Kent State University Professor Dr. C. Owen Lovejoy was a co-author of the research and helped analyze the skeleton. When comparing it to "Lucy," Lovejoy said, "They both have pelves, a complete lower limb bone and elements of the forelimb, vertebral column and thorax. However, the new specimen has more complete ribs and a nearly complete scapula, which tells us much more about body form in Australopithecus afarensis than 'Lucy' was able to alone."

Authors of the research include Cleveland scientists Dr. Bruce Latimer, interim director of the Center for Human Origins of the Institute for the Science of Origins at Case Western Reserve University, and Dr. Beverly Saylor, associate professor of geological sciences at Case Western Reserve University. Other co-authors are from Addis Ababa University in Ethiopia, Berkeley Geochronology Center and Stanford University.

Australopithecus afarenis is the best-known direct early human ancestor. Until now, the only partial skeleton assigned to this species was "Lucy," a 3.2 million-year-old female individual, which was discovered in 1974 by a team led by then Museum curator Dr. Donald Johanson.

The analysis of "Kadanuumuu" indicates that the shoulder and rib cage of this species were different from those of chimpanzees. "These findings further confirm what we concluded from the 'Ardi' specimen -- that chimpanzees have undergone a great deal of specialized evolution since we shared a last common ancestor with them," said Lovejoy.

"Ardi," or Ardipithecus ramidus is a 4.4 milion-year-old hominid species that was unveiled in October 2009 by a team that included Haile-Selassie, Lovejoy, and Museum scientists and associate researchers Dr. Linda Spurlock, Dr. Bruce Latimer and Dr. Scott Simpson. "Ardi" was named by the journal Science as breakthrough discovery of the year. Click here to find out more about "Ardi."

Of Lice and Man: Researchers Sequence Human Body Louse Genome

Like an unwelcome houseguest or itinerant squatter, the human body louse shows up when times are bad and always makes them worse. Now a multi-institutional team reports that it has sequenced the body louse genome, an achievement that will yield new insights into louse -- and human -- biology and evolution.

The study, which also sequenced the genome of a microbe that lives inside the body louse, appears in Proceedings of the National Academy of Sciences.

Thanks to its tenacity, the tiny, blood-sucking parasite Pediculus humanus humanus L. has witnessed, and played a role in, millions of years of human history. The body louse spread epidemic typhus and what is now termed trench fever to Napoleon's retreating army in Russia in 1812, and body lice plagued Lewis and Clark on their adventures in the New World.

The human body louse seems to appear out of nowhere during economic downturns, wars and other crises that cause people to live in unsanitary conditions. It is closely related to the head louse, Pediculus humanus capitis, which also feeds on human blood. But the body louse lives in clothing and, unlike the head louse, can spread bacterial diseases.

The body louse genome is the smallest known genome of any insect, said University of Illinois entomology professor Barry Pittendrigh (pronounced PITT-in-dree), who led the drive to fund the project and coordinated the international team of scientists who analyzed the sequence. The size of the body louse genome probably reflects its rather protected habitat and predictable diet, he said.

"The ecology of lice is very, very simple. It either lives in your hair or on your clothing, and it has one type of meal, and that's blood," he said. "So most of the genes that are responsible for sensing or responding to the environment are very much reduced."

The genome analysis found very few genes for light-sensing protein receptors, for example. University of Illinois entomology professor Hugh Robertson was responsible for sorting out the genes contributing to chemical sensing, and discovered that the louse has significantly fewer taste and odorant receptors than other insects.

The body louse also has "the smallest number of detoxification enzymes observed in any insect," the researchers wrote. John Clark, of the University of Massachusetts at Amherst, and Si Hyeock Lee, of Seoul National University, led this part of the analysis. The body louse's pared-down list of detoxifying enzymes makes it an attractive organism for the study of resistance to insecticides or other types of chemical defense, Pittendrigh said. University of Illinois entomology professor and department head May Berenbaum and former graduate student Reed Johnson contributed to this effort.

The body louse is completely dependent on humans for its survival; it will die if separated from its host for very long. It is just as reliant on a microbe that lives inside it: the bacterium Candidatus Riesia pediculicola.

In the Riesia genome, the team found genes for the production of an essential nutrient, pantothenate (Vitamin B5), which the louse requires and cannot make on its own. The Riesia genome also is quite small in comparison to its closest "free-living" relatives. So too are the genomes of the bacterial pathogens that the body louse transmits to its human hosts: Rickettsia prowazekii (which causes epidemic typhus), Borrelia recurrentis (the agent of relapsing fever) and Bartonella quintana (which causes trench fever). This, the researchers report, will make the body louse a useful tool for understanding the co-evolution of disease-carrying parasites and their bacterial co-conspirators.

The body louse genome will aid a host of other lines of research, Pittendrigh said.

"Lice have been used to understand human evolution and migration. They've been used to estimate when we started wearing clothing," he said. "The genome should also help us develop better methods of controlling both head and body lice."

"Beyond its importance in the context of human health, the body louse genome is of considerable importance to understanding insect evolution," Berenbaum said. "It is only the second genome sequenced to date of an insect with gradual development -- that is, that does not undergo profound anatomical and ecological change as it matures from egg to adult. Although most of the insect species on the planet undergo complete metamorphosis -- developing from egg to caterpillar to pupa to adult -- in fact gradual metamorphosis is the older developmental program. The body louse genome can provide a baseline for understanding how complete metamorphosis, a key to insect domination of the planet, came to evolve."

The genome sequencing effort involved researchers at 28 institutions in the U.S., Europe, Australia and South Korea. First author Ewen Kirkness coordinated sequencing and gene identification at the J. Craig Venter Institute. Clark; Lee; Spencer Johnson, of Texas A&M University; Jeanne Romero-Severson, of the University of Notre Dame; Greg Dasch, of the Centers for Disease Control and Prevention; and Pittendrigh wrote the original proposal to obtain funding for the genome sequencing effort from the National Institutes of Health and guided the effort. Evgeny Zdobnov and his team conducted the evolutionary analysis.

Six New Planets Discovered

An international team, including Oxford University scientists, has discovered six diverse new planets, from 'shrunken-Saturns' to 'bloated hot Jupiters', as well a rare brown dwarf with 60 times the mass of Jupiter.

The CoRoT (Convection, Rotation and Transits) space telescope is operated by the French space agency CNES. It discovers planets outside our solar system -- exoplanets -- when they 'transit', that is pass in front of their stars.

Once CoRoT detects a transit, additional observations are made from the ground, using a number of telescopes all over the world. Although astronomers cannot see the planets directly, they use the space- and ground-based data to measure the sizes, masses, and orbits of these new planets precisely. This is why, among all known exoplanets, those with transits yield the most complete information about planet formation and evolution.

"Each of these planets is interesting in its own right, but what is really fascinating is how diverse they are," said co-investigator Dr. Suzanne Aigrain from Oxford University's Department of Physics. "Planets are intrinsically complex objects, and we have much to learn about them yet."

"Every discovery of an extrasolar planetary system is a new piece in the puzzle of how these systems do form and evolve. The more systems we uncover, the better we can hope to understand the processes at play," said Magali Deleuil, researcher at the Laboratoire d'Astrophysique de Marseille (LAM) and head of the CoRoT exoplanet program.

The six new planets are:

CoRoT-8b: the smallest in this batch: At about 70% of the size and mass of Saturn, CoRoT-8b is moderately small among the previously known transiting exoplanets. Its internal structure should be similar to that of ice giants, like Uranus and Neptune, in the Solar System. It is the smallest planet discovered by the CoRoT team so far after CoRoT-7b, the first transiting Super-Earth.

CoRoT-10b: the eccentric giant: The orbit of CoRoT-10b is so elongated that the planet passes both very close to and very far away from its star. The amount of radiation it receives from the star varies tenfold in intensity, and scientists estimate that its surface temperature may increase from 250 to 600°C, all in the space of 13 Earth-days (the length of the year on CoRoT-10b).

CoRoT-11b: the planet whose star does the twist: CoRoT-11, the host star of CoRoT-11b, rotates around its axis in 40 hours. For comparison, the Sun's rotation period is 26 days. It is particularly difficult to confirm planets around rapidly rotating stars, so this detection is a significant achievement for the CoRoT team.

CoRoT-12b, 13b and 14b: a trio of giants: These three planets all orbit close to their host star but have very different properties. Although CoRoT-13b is smaller than Jupiter, it is twice as dense. This suggests the presence of a massive rocky core inside the planet. With a radius 50% large than Jupiter's (or 16 times larger than the Earth's), CoRoT-12b belongs to the family of `bloated hot Jupiters', whose anomalously large sizes are due to the intense stellar radiation they receive. On the other hand, CoRoT-14b, which is even closer to its parent star, has a size similar to Jupiter's. It is also massive, 7.5 times the mass of Jupiter, which may explain why it is less puffed up. Such very massive and very hot planets are rare, CoRoT-14b is only the second one discovered so far.

CoRoT-15b: the brown dwarf: CoRoT-15b's mass is about 60 times that of Jupiter. This makes it incredibly dense, about 40 times more so than Jupiter. For that reason, it is classified as a brown dwarf, intermediate in nature between planets and stars. Brown dwarfs are much rarer than planets, which makes this discovery all the more exciting.

Dr. Suzanne Aigrain leads a team of UK researchers at the Universities of Oxford, Exeter and St Andrews who participate in the CoRoT exoplanet program. Their research is supported by the Science and Technology Facilities Research Council.

Why Estonia Is the Poster Child for Cyber-Security

I'm just back from a conference on cyber security held in Estonia, or, as the editors always force me to write: "the tiny Baltic nation of Estonia." Other popular tropes: "in Estonia, more than 90 percent of all banking is done online, digital signatures are used widely by government officials and you can pay for parking with your cell phone. Geeks have dubbed the place E-stonia. Oh, and four Estonians built Skype."

Right, we get it. Twenty years ago, the country shook free of the Soviets and made a strategic decision to invest, heavily, in information technology. The country's President, Toomas Hendrik Ilves, put it this way: "We are a small, unassuming European country that's fairly advanced when it comes to Internet applications."

You may also remember that the last time Estonia was in the headlines was back in 2007, when a series of denial of service attacks wrecked havoc with the the e-services that Estonians have come to depend on, and expect. The attacks began at the same time a real-world battle had developed over the fate of a statue of a Russian soldier in Tallinn. Online, banks, newspapers, and some government ministry websites were on the target list.

Some accused the Russians of coordinating the attacks, although no conclusive proof has ever been shown. Likewise, groups inside and outside Russia have claimed responsibility, but that's never proven either. To date, one student in Tallinn has been convicted of being involved. His punishment? A $1,500 fine.

At the time, headlines outside of the country did a lot of screaming about "Cyber-War!!" etc. The Estonians took things a bit more in stride, and got to work getting their systems back online. The attack was "the IT equivalent of a paleolithic attack with rocks and clubs," President Ilves said. "But we know that even attacks with rocks and clubs can cause damage."

Ilves was speaking last week in the capital Tallinn, at the opening of a major conference on cyber-security. Since 2008, Estonia has also been home to the Cooperative Cyber Defense Center of Excellence (CCD COE), a NATO-approved think-tank whose mission is essentially to formulate new strategies for understanding, and preventing, online attacks. Representatives from across NATO countries and beyond use the center to carry out research and share information.

The Center was actually in the works long before the attacks, but they did lend an added urgency to the need for concentrated, coordinated and above all global thinking when it comes to fending off Internet attacks. It's not just about dealing with the technical aspects of understanding and eliminating threats. It's also thinking about how we update our national laws, and the laws of war, into a world where, as Ilves said, "You don't need a tank. All you need is a keystroke."

Estonia has, it must be said, become something of a poster child for the whole notion of "cyber-war." There's a lot of fear-mongering right now about "Internet Pearl Harbors" and "Cyber 9-11s." But here's the thing that the experts gathered in Tallinn agreed on: we don't even know how to define "cyber-war," either from a strategic point of view, or a legal point of view. And without a conceptual framework for it, it's hard to know how to prevent it, or who to hold responsible for it.

What strikes me, in reflecting on the interviews I did in Tallinn, was how much we all might be able to learn from the way the Estonians dealt with the cyber-attacks in 2007, and how they continue to deal with both online threats, and the attention they bring.

Estonia's Defense Minister, Jaak Aaviksoo, has spent three years thinking about these things. On the attention focused on Estonia he says, "I wouldn't say it's good or bad. I have to live with it." He's philosophical when it comes to dealing with a future filled with online threats: "New technologies emerge every day, and both the good guys and the bad guys have access to them. We can't monopolize technology into the good guys' hands." The only way we'll learn to move forward, he says, is by going through a painful growing process of suffering from, and dealing with, online attacks.

Another official told me that Estonians haven't been frightened off of IT by the 2007 attacks. On the contrary, she said, they are using e-services more than ever. "We're too used to them now to give them up," she told me.

"Just because you get mugged once in a park," she said, "doesn't mean you stop going to parks."

If you want to read and hear more about the conference, by the way, I wrote it up for BBC News online, and for public radio radio too.

Are We Overlooking Alien Beacons?

Last week Hubble Space Telescope images definitively showed that the bright flash of light seen on Jupiter was simply a meteor. Albeit, a blinding bright meteor to be seen across 400 million miles of interplanetary space. As reported by Ian O’Neill Hubble failed to find any telltale debris as seen in Jupiter comet and asteroid impacts.

Now Hubble astronomers tell us that Jupiter super-meteors might be detectable as frequently every few days. Australian amateur astronomer Anthony Wesley just got lucky because he was viewing a video transmission of Jupiter when the brilliant flash appeared.

This event was sobering to me because my mind invariably wandered to wondering if a signal from an extraterrestrial civilization might be just as transient.

SLIDE SHOW: Top 10 Places to Find Alien Life
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WATCH VIDEO: Will the real ET be little green men or little green bacteria?

Despite our best search strategies, are signals from E.T. manifested in anomalous flashes of radio energy from our galaxy that are missed, or dismissed as natural phenomena? Maybe alien transmissions are popping off all around us but we just aren’t looking at the right place or right time to seen them.

In a recently published paper by James Benford and Dominic Benford of Microwave Sciences in Lafayette, California, the authors imagine that SETI beacons might be much like a lighthouse, sweeping the galactic plane in a raster pattern. Depending on beam size and scan rate, many days could pass between the brief Twitter-like bursts of “here we are” flashes from alien civilizations.

"We should learn how to identify any such beacons," the authors say. For starters they expect the beam would pulsate to conserve energy and also have amplitude or frequency modulation of the carrier to draw attention to itself.

WIDE ANGLE: Are We Alone?
Blazar1


The problem is that pulsars (powerful bursts of radiation from rotating neutron star magnetospheres) look just what an alien transmission might look like according to this SETI "lighthouse" model. In fact when pulsars were first discovered in the mid 1960’s they were nicknamed “LGMs” for “Little Green Men.”

There are certain unusual transient phenomena that are likely due to pulsars behaving, well, unusually. These occasionally repeat, but others do not. The authors say that we should consider SETI beacons as a candidate explanation when perplexing non-repeating signals that are seen in the radio sky.

One example they cite is PSR J1928+15 that was a transient burst of radio pulses that was observed only for two minutes in 2005 near the galactic plane -- and never repeated in several dozen subsequent searches. Three pulses came in succession. The first and third pulse was down a factor of ten from the powerful central pulse. The source is estimated to be 26,000 light years away, the distance to the heart of our galaxy.

The SETI-lighthouse hypothesis would explain PSR J1928+15 as an E.T. scanning beacon. As it swept past Earth, the giant Arecibo radio telescope in Puerto Rico caught the central pulse of the true beam. The first and third pulses were at the edges of the beam width according to this interpretation.

Pulsar seti
A far simpler explanation is that the transient was caused by an asteroid falling into the neutron star from a circumpulsar disk. This perturbed the pulsar’s intense magnetic field.

If we diligently apply Occam’s Razor (going with the simplest explanation) the crashing asteroid solution wins over E.T. saying “Hi.”

Also, the central beam pulse was 190,000 terawatts -- 10,000 times the total power output of our civilization! I wouldn't want to pay that electric bill.

Still, this kind of mega-engineering would be cheaper than the ticket price high-speed interstellar travel. The authors say there might be a scaling effect where super-civilizations build extraordinarily powerful transmitters. These aliens might have limitless armies of self-replicating machines that tirelessly construct vast antenna arrays orbiting a star and sucking up solar energy.

Another problem is that such civilizations are probably rare in the galaxy. And, at the same time we need to assume that they’d decide to stick with radio wavelengths as a viable communications channel for reaching any entities they would be interested in contacting.

Less ambitious or less advanced civilizations might try beacons too, but the beams would be weaker, though likely to be more numerous in the galaxy.

Seti array

The dilemma is that exotic astrophysics theories, no matter how exotic, would always trump any conclusion that super-aliens where pumping out extravagantly powerful broadcasts. Even suggesting “I fount E.T.” could be a career-killer for any young astronomer.

If such artificially produced flashes are real, they will likely remain ghosts in the cosmic night that are as fleeting as Jupiter’s super-meteors.