Oct 8, 2011

Reefs Recovered Faster After Mass Extinction Than First Thought

Metazoan-dominated reefs only took 1.5 million years to recover after the largest species extinction 252 million years ago, an international research team including paleontologists from the University of Zurich has established based on fossils from the southwestern United States.

Harsh living conditions caused by major fluctuations in the carbon content and sea levels, overacidification and oxygen deficiency in the seas triggered the largest mass extinction of all time at the end of the Permian era 252 million years ago. Life on Earth was also anything but easy after the obliteration of over 90 percent of all species: Throughout the entire Early Triassic era, metazoan-dominated reefs were replaced by microbial deposits. Researchers had always assumed it took Earth as long as five million years to recover from this species collapse.

Now, however, an international team, including the paleontologist Hugo Bucher from the University of Zurich and his team of researchers, has shown that reefs already existed again in the southwest of what is now the USA 1.5 million years after the mass extinction. These were dominated by metazoan organisms such as sponges, serpulids and other living creatures, the researchers report in Nature Geoscience.

Read more at  Science Daily

Computer Chemicals Linked to Pancreatic Cancer

Chemicals associated with the production of computers and other electronic equipment can be present in high levels in patients suffering from pancreatic cancer, the disease that Steve Jobs was diagnosed with in 2004.

Over the past decade, awareness and concern about computer chemicals and other related components, such as arsenic, cadmium, lead, benzene and hydrochloric acid, have increased. The European Union, for example, now restricts hazardous substances in electrical and electronic equipment. Apple, as for PC manufacturers, admits to receiving criticism from environmental organizations, and now calls itself  "a greener Apple."

Despite such efforts, computers are still full of toxins, and many older electronic devices remain in  homes and businesses. One pervasive and potentially dangerous component is cadmium, which should be carefully recycled. This soft, silver-white metal is in paints, alloys, cathode ray tubes, and more. It's perhaps best known for use in nickel-cadmium batteries, which deliver a lot of power for the money and are rechargeable.

Cadmium also appears to be directly tied to pancreatic cancer.

The northeast Nile Delta region of Egypt exhibits a high incidence of early-onset pancreatic cancer. This region is one of the most polluted areas of Egypt, with the pollutants often winding up in soil and affecting farm workers. Researchers conducted a study to explore the possible connection between cadmium and the often deadly cancer.

Alison Kriegel of Tulane University Health Sciences Center and her colleagues assessed blood cadmium levels of 31 newly diagnosed pancreatic cancer patients and 52 hospital comparison subjects from Mansoura, Egypt. The scientists "found a significant difference between the mean serum cadmium levels in patients versus comparison subjects but not in age, sex, residence, occupation, or smoking status."

The study further point out that two commonly mentioned risk factors for pancreatic cancer -- age and smoking -- can also be associated with cadmium.

The authors explain: "Cadmium accumulates in the body over time because there are no specific mechanisms for its removal. The half-life of this metal in the body ranges from 10 to 30 years, with an average of 15 years. In addition, cigarette smoking is a significant source of cadmium. One cigarette contains 1–2 μg cadmium, and inhaled cadmium is absorbed much more efficiently than is ingested cadmium."

Certain people may also have a family history of cancer, making them more genetically suscptible to it.

While studies continue to show links between cancer and cadmium, as well as numerous other chemicals and components used to manufacture electronics, it remains a challenge to tease apart what risk factors, without a doubt, contribute to instances of the disease.

Pancreatic cancer is now the fourth leading cause of cancer death, according to the American Cancer Society. However, the type that Steve Jobs had, pancreatic neuroendocrine cancer, is considered to be quite rare.

Read more at Discovery News

Oct 7, 2011

Genetic Link to Suicidal Behavior Confirmed

A new study from the Centre for Addiction and Mental Health has found evidence that a specific gene is linked to suicidal behaviour, adding to our knowledge of the many complex causes of suicide. This research may help doctors one day target the gene in prevention efforts.

In the past, studies have implicated the gene for brain-derived neurotrophic factor (BDNF) in suicidal behaviour. BDNF is involved in the development of the nervous system.

After pooling results from 11 previous studies and adding their own study data involving people with schizophrenia, CAMH scientists confirmed that among people with a psychiatric diagnosis, those with the methionine ("met") variation of the gene had a higher risk of suicidal behaviour compared to those with the valine variation.

The review, published in the International Journal of Neuropsychopharmacology, included data from 3,352 people, of whom 1,202 had a history of suicidal behaviour.

"Our findings may lead to the testing and development of treatments that target this gene in order to help prevent suicide," says Dr. James Kennedy, director of CAMH's Neuroscience Research Department. "In the future, if other researchers can replicate and extend our findings, then genetic testing may be possible to help identify people at increased risk for suicide."

As the low-functioning BDNF met variation is a risk factor for suicidal behaviour, it may also be possible to develop a compound to increase BDNF functioning, Dr. Kennedy says.

About 90 per cent of people who have died by suicide have at least one mental health disorder, the researchers note. Within the studies they reviewed, participants had schizophrenia, depression, bipolar disorder or general mood disorders. In each case, the researchers compared the genotypes of people who had attempted or completed suicide with those who were non-suicidal.

"Our findings provide a small piece of the puzzle on what causes suicidal behaviour," says Dr. Kennedy.

Read more at Science Daily

Prehistoric Dog Found with Mammoth Bone in Mouth

The remains of three Paleolithic dogs, including one with a mammoth bone in its mouth, have been unearthed at Předmostí in the Czech Republic, according to a new Journal of Archaeological Science paper.

The remains indicate what life was like for these prehistoric dogs in this region, and how humans viewed canines. The dogs appear to have often sunk their teeth into meaty mammoth bones. These weren’t just mammoth in terms of size, but came from actual mammoths.

In the case of the dog found with the bone in its mouth, the researchers believe a human inserted it there after death.

"The thickness of the cortical bone shows that it is from a large mammal, like a rhinoceros, steppe bison or mammoth," lead author Mietje Germonpré told Discovery News. "At Předmostí, mammoth is the best represented animal, with remains from more than 1,000 individuals, so it is probable that the bone fragment is from a mammoth."

Germonpré, a paleontologist at the Royal Belgian Institute of Natural Sciences, and colleagues Martina Laznickova-Galetova and Mikhail Sablin, first studied the remains, focusing on the skulls, to see what animals they represented. In the fossil record, there is sometimes controversy over what is a wolf, dog or other canid.

"These skulls show clear signs of domestication," Germonpré said, explaining they are significantly shorter than those of fossil or modern wolves, have shorter snouts, and noticeably wider braincases and palates than wolves possess.

She described them as large, with an estimated body weight of just over 77 pounds. The shoulder height was at least 24 inches.

"The shape of their skull resembles that of a Siberian husky, but they were larger and heavier than the modern Husky," she said.

The dogs died when they were between 4 and 8 years old, suffering from numerous broken teeth during their lifetimes.

Based on what is known of the human culture at the site, the researchers believe these dogs “were useful as beasts of burden for the hauling of meat, bones and tusks from mammoth kill sites and of firewood, and to help with the transport of equipment, limiting the carrying costs of the Předmostí people.”

Since mammoth meat was likely the food staple, the scientists further believe that the surplus meat “would have been available to feed the dogs.”

The dog skulls show evidence that humans perforated them in order to remove the brain. Given that better meat was available, the researchers think it’s unlikely the brains served as food.

Instead, based on these archaeological finds and the ethnographic record, it’s possible that the body manipulation after death held ritual importance.

Read more at Discovery News

Jumping Fish Shed Light on Evolution

Any fisherman or flying fish fan knows that fish can execute impressive jumps, but new research demonstrates these leaps can happen with height and precision on land too.

Considering that fish don't have legs, wings, arms, or other helpful anatomy to control such jumps, the feat seems almost improbable.

Alice Gibb of the Northern Arizona University Biology Department and her team proved it can happen after studying several different types of fish jumping with apparent skill and purpose. The research, published in the Journal of Experimental Zoology: Ecological Genetics and Physiology, was inspired by a mangrove rivulus jumping out of a small net and back into the water. The move wasn't just a random flop, Gibb noticed. The fish seemed to be in full control.

This control wasn't lost on land either, which has significant implications for evolutionary biology, Gibb said, because the finding implies that "the invasion of the land by vertebrates may have occurred much more frequently than has been previously thought."

In other words, land life on Earth probably started with leaps and bounds, with terrestrial jumping by fully aquatic fish.

Gibb said the study "supports a big-picture theory in evolution," which is that the nervous system, in its control of bones and muscles, can allow a new behavior to appear without necessarily bringing about a physical change.

In the case of aquatic fish, Gibb said, "This shows that you don't have to have legs or rigid pectoral fins to move around on land. So if you go back and look at the fossil record to try to say which fish could move around on land, you’d have a hard time knowing for sure."

The scientists' tests on everything from guppies to mosquitofish demonstrated that even clearly non-amphibious fish could jump with skill and direction on land.

The mosquitofish "has become our lab rat," Gibb said. "It's accessible, it comes from a group that has other jumpers, and it’s been reported that this fish jumps out of the water to get away from predators and then jumps back in."

Read more at Discovery News

Oct 6, 2011

Biologists Find 'Surprising' Number of Unknown Viruses in Sewage

Though viruses are the most abundant life form on Earth, our knowledge of the viral universe is limited to a tiny fraction of the viruses that likely exist. In a paper published in the online journal mBio, researchers from the University of Pittsburgh, Washington University in St. Louis, and the University of Barcelona found that raw sewage is home to thousands of novel, undiscovered viruses, some of which could relate to human health.

There are roughly 1.8 million species of organisms on our planet, and each one is host to untold numbers of unique viruses, but only about 3,000 have been identified to date. To explore this diversity and to better characterize the unknown viruses, Professor James Pipas, Distinguished Professor of Biological Sciences Roger Hendrix, and Assistant Professor Michael Grabe, all of the Department of Biological Sciences in Pitt's Kenneth P. Dietrich School of Arts and Sciences, are developing new techniques to look for novel viruses in unique places around the world.

With coauthors David Wang and Guoyan Zhao of Washington University in St. Louis and Rosina Girones of the University of Barcelona, the team searched for the genetic signatures of viruses present in raw sewage from North America, Europe, and Africa.

In the paper, titled "Raw Sewage Harbors Diverse Viral Populations," the researchers report detecting signatures from 234 known viruses that represent 26 different families of viruses. This makes raw sewage home to the most diverse array of viruses yet found.

"What was surprising was that the vast majority of viruses we found were viruses that had not been detected or described before," says Hendrix.

The viruses that were already known included human pathogens like Human papillomavirus and norovirus, which causes diarrhea. Also present were several viruses belonging to those familiar denizens of sewers everywhere: rodents and cockroaches. Bacteria are also present in sewage, so it was not surprising that the viruses that prey on bacteria dominated the known genetic signatures. Finally, a large number of the known viruses found in raw sewage came from plants, probably owing to the fact that humans eat plants, and plant viruses outnumber other types of viruses in human stool.

This study was also the first attempt to look at all the viruses in the population. Other studies have focused on bacteria, or certain types of viruses. The researchers also developed new computational tools to analyze this data. This approach, called metagenomics, had been done before, but not with raw sewage.

The main application of this new technology, says Hendrix, will be to discover new viruses and to study gene exchange among viruses. "The big question we're interested in is, 'Where do emerging viruses come from?'" he says. The team's hypothesis is that new viruses emerge, in large part, through gene exchange. But before research on gene exchange can begin in earnest, large numbers of viruses must be studied, the researchers say.

Read more at Science Daily

Prehistoric Teen Girl's Grave Found Near Henge

Four to five thousand years ago, a wealthy teenage girl was laid to rest in a grave at what archaeologists believe is a newly found henge in Kent, England.

The discovery of the 17-year-old's grave -- along with a unique prehistoric pot inside of a ringed ditch near two other women -- strengthens the idea that important death-related rituals took place at many of these mysterious ancient monuments when they were first erected.

Mystery still surrounds Stonehenge and other sacred sites in the U.K., but a new probable henge in Kent strengthens the idea that important death-related rituals took place at many of these monuments when they were first erected 5000 to 4000 years ago.

"What is becoming clear is that with a series of major excavations in Kent linked to road and rail works, and new aerial photography, there are many circular earthworks that look part barrow and part henge, and like the one fully excavated example at Ringlemere (Kent), some of these may be both," said archaeologist Mike Pitts, publisher of British Archaeology, where a summary of the recent finds appears.

"This comes after many years in which archaeologists believed there were no henges in south-east England at all," Pitts told Discovery News.

Staff from Oxford Wessex Archaeology, during recent extensive excavations, discovered the early teen's grave on the Isle of Thanet, Kent, near what is now Manston Airport. The girl was buried laying on her side with flexed limbs, with an unusual pot standing by her right elbow.

Pitts explained that the pot consists of three small bowls joined together. Separately made pots were joined with bridging clay before decorating and firing, he suspects. Neil Wilkin, a researcher at the University of Birmingham studying early vessels, said the features of the pot confirm its suspected age and attribution.

Only one other example of multiple joined pots from the time has been seen before, Pitts said. In that other case, just two small bowls were attached together.

Two other women, aged 25-30 and 35-50, were also found buried inside the 72 feet-wide ditch. It remains unclear if the number of attached pots was somehow tied to the number of women found at the site. What is clear is that they must have been wealthy individuals. A conical amber button was located near the teenager's head. She might have then worn clothing bejewelled with amber accents.

A separate Kent excavation, near Maidstone, uncovered the new likely henge. Such monuments are seen across Britain, but this latest one may be only the second henge known to exist in south-east England.

Read more at Discovery News

Steve Jobs: Dents in the Universe

Steve Jobs was a visionary, a marketer and a perfectionist, but he was also a quote machine. One of his better lines was this exhortation to Apple employees: "Make a dent in the universe."

Apple chief executive Steve Jobs died too soon Wednesday at age 56 -- only months after his resignation as chief executive of the company he co-founded, but long after he, his colleagues, and those inspired and empowered by their work had pounded a series of dents into the universe.

For me, the first one felt was the arrival of the Mac. To sit down in front of a Mac Plus in high school (especially if you, hypothetically speaking, had an IBM PCjr at home) was to be awakened: Yes, this is how things could work. What you saw on the screen could be what came out of the printer, not a crude, 80-characters-per-line simulation.

But before I'd figured that out, Jobs had long since been kicked out of Apple.

He rebooted his career to found NeXT Computer -- the World Wide Web was developed on a NeXT workstation -- and help launch Pixar. Too few paid attention to either move at the time, not least since Apple prospered without him for several years.

By the time the rot had set in at Apple in the mid-1990s and the increasingly desperate firm bought NeXT in 1997, few industry observers, myself included, expected great things from the founder's return.

Jobs had other plans. He led one of the greatest corporate reinventions in American history, first rudely discarding ventures like the Newton and Apple's licensing of the Mac operating system to "Mac clone" manufacturers, then shipping the first of many versions of the iMac and the NeXT-based Mac OS X operating system.

The iPod turned Apple into a consumer electronics competitor, the iPhone reset and continues to redefine the smartphone, and the iPad took ownership of the tablet-computing market. Apple software such as iMovie let "mere mortals," as Jobs liked to say during his product keynotes, aspire to making their own Pixar-worthy productions.

The iTunes Store liberated music buyers from the recording industry's condescending attempts to control music downloads. The App Store freed mobile phone software from the dictates of the wireless carriers -- although it then subjected them to Apple's largely unaccountable curation.

Read more at Discovery News

Oct 5, 2011

Meet LUCA: Our Complex Ancestor

The relative of all living things, dubbed the Last Universal Common Ancestor (LUCA), was a sophisticated organism with a complex structure recognizable as a cell, according to a new paper in the journal Biology Direct.

Prior theories have held that this great-grandparent of all living things was little more than a crude assemblage of molecular parts, a chemical soup out of which evolution gradually constructed more complex forms. This latest research suggests that was not the case, although LUCA was not a multi-celled creature.

“LUCA was probably a single celled organism because the extracellular machinery needed for multicellularity was developed in eukaryotes (organisms whose cells contain microstructures) very late in evolution,” lead author Manfredo Seufferheld told Discovery News.

“We do not know its appearance, but we hypothesize it looked very much like an archaeum,” added Seufferheld, who is a professor of crop sciences at the University of Illinois.

The archaea are a group of microorganisms that are somewhat similar to, but genetically distinct from, bacteria.

The study builds on research into a once-overlooked feature of microbial cells, a region with a high concentration of polyphosphate.Seufferheld and colleagues Kyung Kim, James Whitfield, Alejandro Valerio and���tavo Caetano-Anollés made the determinations after studying this region of cells which is a type of energy currency.

Through genetic analysis, including the construction of “family trees,” the researchers demonstrated how this polyphosphate storage site actually represents the first known universal organelle. Such specialized subunits, organelles, were once thought to be absent from bacteria and their distantly related microbial cousins, the archaea.

The evidence now indicates the organelle dates back to LUCA, before the three main branches of the tree of life appeared. It is therefore likely present in the three primary domains of today’s Earthly life. These are bacteria, archaea and eukaryotes (plants, animals, fungi, algae and everything else).

“We hypothesize that LUCA developed this organelle very early in evolution so that it could have a sustainable source of energy stored in its cellular make up,” Seufferheld explained, adding that mitochondria (organelles functioning as cellular power plants) “were later developed and replaced the major energetic role” of the polyphosphate storage site when Earth became oxygenated.

The findings add to what is already suspected about LUCA, thought to have emerged about 3.8 billion years ago.

Nicolas Lartillot, a bio-informatics professor at the University of Montreal, and his team also conducted genetic and tree of life analyses. These suggest early life on Earth was composed of ribonucleic acid (RNA) rather than DNA. RNA is particularly sensitive to heat, so this provides yet another clue about LUCA.

Lartillot said that “our data suggests that LUCA was actually sensitive to warmer temperatures and lived in a climate below 50 degrees.”

He said this negates the idea “that LUCA was a heat-loving or hyperthermophilic organism. A bit like one of those weird organisms living in the hot vents along the continental ridges deep in the oceans today.”

Read more at Discovery News

Monkeys play computer games with their minds

Two rhesus monkeys learned to operate a virtual arm with their brain power and were able to differentiate between the textures of virtual objects they were "feeling".

It is hoped this could pave the way for the development of a ''robotic exoskeleton'' to be worn by severely paralysed people, helping them move and experience the world around them using brainwaves.

Miguel Nicolelis, co-director of the Duke University Centre for Neuroengineering in Durham, North Carolina, said: ''Someday in the near future, quadriplegic patients will take advantage of this technology not only to move their arms and hands and to walk again, but also to sense the texture of objects placed in their hands, or experience the nuances of the terrain on which they stroll with the help of a wearable robotic exoskeleton.''

The electrical brain activity of the two rhesus monkeys trained at the centre was used to direct the hands of a virtual monkey shown on a screen - without them moving any part of their real bodies.

The virtual hands were then used to explore the surface of three virtual objects, which looked the same but had been designed to have different textures, which were expressed as tiny electrical signals sent back to the monkeys' brains.

In the task, the monkeys had to search for a virtual object with a particular texture and were rewarded with fruit juice if they correctly identified it.

Professor Nicolelis said the study, published in the journal Nature, gave hope to people with spinal cord lesions because feedback on textures took place without any movement of the monkey's body.

He said: ''We hope that in the next few years this technology could help to restore a more autonomous life to many patients who are currently locked in without being able to move or experience any tactile sensation of the surrounding world.

''This is also the first time we've observed a brain controlling a virtual arm that explores objects while the brain simultaneously receives electrical feedback signals that describe the fine texture of objects 'touched' by the monkey's newly acquired virtual hand.

''Such an interaction between the brain and a virtual avatar was totally independent of the animal's real body, because the animals did not move their real arms and hands, nor did they use their real skin to touch the objects and identify their texture.

''It's almost like creating a new sensory channel through which the brain can resume processing information that cannot reach it anymore through the real body and peripheral nerves.''

Read more at The Telegraph

Did Ocean Water Originate From Comets?

A family of comets from the Kuiper Belt may have assisted asteroids with bringing water to early Earth, a key development in the planet's ability to host life.

Scientists believe Earth’s water was delivered sometime after the planet formed, as its close proximity to the sun would have boiled off water inside rocks that were part of the original building materials.

Previous studies of meteorites, which are bits of asteroids that land on Earth, show a water chemistry that is similar to Earth’s oceans. The analysis is based on the ratio of regular water -- two hydrogen atoms bound with an oxygen atom, or H2O -- and so-called “heavy water,” which has an extra neutron in its nucleus.

The ratio was different in a handful of measurements made of comets, so scientists theorized that asteroids were the primary source of Earth’s water.

Not so, concludes a new study that looked at a comet hailing from a different part of the solar system than previously studied comets.

The target, Comet Hartley 2, is believed to have formed in the Kuiper Belt region, located beyond Neptune's orbit. Hartley 2 is now a member of the Jupiter family of short-period comets that swing around the sun in less than 20 years. The comet's water chemistry matches that of Earth's.

"This is an important constraint on models of the formation of planets in the solar system, a field of science which is moving forward very rapidly at present," astronomer Miriam Rengel of the Max Planck Institute for Solar System Research in Germany, wrote in an email to Discovery News.

Previous studies, which looked at comets originating from the Oort cloud, a spherical cluster of icy bodies in the outer solar system, led scientists to conclude that only about 10 percent of Earth's water could have come from comets.

Read more at Discovery News

Lava Rocks: Cradle for Life on Earth?

Early life may have formed between a rock and a wet place.

Floating rafts of lava rock had the right conditions to nurture life as it emerged from the primordial ooze of chemicals in the Earth's early oceans. Researchers from the University of Oxford in England suggest lava rock, or pumice, had four special qualities that may have made it the cradle of life.

1. Only the cruelest of mothers would put her baby in a lava rock cradle. But for Mother Nature, the sharp nooks and crannies of lava rock that torture bare feet also made the rock a great shelter for the chemical reactions that led to life. The many crevices provide a large surface area compared to the volume of the rock.

2. Pumice “is the only known rock type that floats as rafts at the air-water interface and then becomes beached in the tidal zone for long periods of time,” wrote the researchers in the journal Astrobiology.

Wading near the beaches of the early Earth would create a mix of water, solids and air from which the building blocks of life could be drawn. Plus, like a modern day beach-goer, the chemical soup would be soaking up the sun, giving it a dose of UV radiation, which could have caused chemical reaction leading to more complex organic chemicals and eventually life.

3. As they floated on the surface of the sea and bumped into the shore, the lava rock was exposed to a wide variety of conditions, including lightning strikes and dehydration. The changing conditions could have fostered chemical reactions leading to life.

4. “Finally, from rafting to burial, it (pumice) has a remarkable ability to adsorb metals, organics, and phosphates as well as to host organic catalysts such as zeolites and titanium oxides,” wrote the researchers.

Metals, organics, and phosphates are the construction materials for building life. The organic catalysts are the tools and workers that get the job done faster than it would happen randomly.

Read more at Discovery News

Oct 4, 2011

Recent Human Evolution Detected in Quebec Town History

Though ongoing human evolution is difficult to see, researchers believe they’ve found signs of rapid genetic changes among the recent residents of a small Canadian town.

Between 1800 and 1940, mothers in Ile aux Coudres, Quebec gave birth at steadily younger ages, with the average age of first maternity dropping from 26 to 22. Increased fertility, and thus larger families, could have been especially useful in the rural settlement’s early history.

According to University of Quebec geneticist Emmanuel Milot and colleagues, other possible explanations, such as changing cultural or environmental influences, don’t fit. The changes appear to reflect biological evolution.

“It is often claimed that modern humans have stopped evolving because cultural and technological advancements have annihilated natural selection,” wrote Milot’s team in their Oct. 3 Proceedings of the National Academy of Sciences paper. “Our study supports the idea that humans are still evolving. It also demonstrates that microevolution is detectable over just a few generations.”

ow humans evolve in modern societies is an enduringly fascinating question. It’s easy to assume that, in an age of developed-world plenty, biological evolutionary pressures have ceased, and biological evolution is supposedly too slow to detect in time scales of a few generations.

In fact, genetic signals of recent human evolution have been found, and there’s even reason to think it’s speeding up. But such genetic signatures, unconnected for now to identifiable traits, are far less glamorous and tangible than fertility.

Milot’s team based their study on detailed birth, marriage and death records kept by the Catholic church in Ile aux Coudres, a small and historically isolated French-Canadian island town in the Gulf of St. Lawrence. It wasn’t just the fact that average first birth age — a proxy for fertility — dropped from 26 to 22 in 140 years that suggested genetic changes. After all, culture or environment might have been wholly responsible, as nutrition and healthcare are for recent, rapid changes in human height. Rather, it was how ages dropped that caught their eye.

The patterns fit with models of gene-influenced natural selection. Moreover, thanks to the detailed record-keeping, it was possible to look at other possible explanations. Were better nutrition responsible, for example, improved rates of infant and juvenile mortality should have followed; they didn’t. Neither did the late-19th century transition from farming to more diversified professions.

“I am inclined to have faith in the analyses since they are established within the quantitative genetic community,” said University of Utah anthropologist Henry Harpending, who has studied changing rates of human evolution. “Evolution, gene frequency change, can work in a hurry and is working all the time in our species.”

According to Harpending, the findings are part of a trend away from assuming that changes in populations are always environmental. “Here and elsewhere we are discovering that changes are due to genetic changes, not changes in the environment,” he said.

Read more at Wired Science

9/11 Terrorists Debunk 9/11 Conspiracies

In a surprising twist, terrorist group al-Qaeda recently issued a statement ridiculing 9/11 conspiracy theories claiming U.S. involvement in the attacks.

The victims and the perpetrator of the terrorism are both saying that Osama bin Laden and al-Qaeda acted alone and without any knowledge or support from the American government. The statement came in response to a speech that the Iranian President gave at the U.N. General Assembly in which he repeated his claim that the U.S. masterminded the terrorism. As ABC News reported last week,

    The terror group al-Qaeda has found itself curiously in agreement with the "Great Satan"--which it calls the U.S. -- in issuing a stern message to Iranian President Mahmoud Ahmadinejad: stop spreading 9/11 conspiracy theories. In the latest issue of the al Qaeda English-language magazine Inspire, an author appears to take offense to the "ridiculous" theory repeatedly spread by Ahmadinejad that the 9/11 terror attacks were actually carried out by the U.S. government in order to provide a pretext to invade the Middle East. "The Iranian government has professed on the tongue of its president Ahmadinejad that it does not believe that al Qaeda was behind 9/11 but rather, the U.S. government," an article reads. "So we may ask the question: why would Iran ascribe to such a ridiculous belief that stands in the face of all logic and evidence?"

If anyone in the world would have hard evidence of American collusion in carrying out the September 11, 2001, attacks (and strong motivation for making it public), it would be al-Qaeda. If the conspiracy claims are true, al-Qaeda would have no reason to deny that America helped organize and carry out the attacks. It would call into question the American government’s credibility in a way that various ad hoc conspiracy theorists could never hope to, and forever tarnish America’s political and moral legitimacy.

Of course terrorism has fueled many conspiracy theories. Earlier this year, conspiracies circulated that Osama bin Laden had not actually been killed by American commandos. I wrote a column about it, pointing out that the best proof that bin Laden is dead is that he hasn’t been seen since his death was announced by President Obama. If bin Laden is alive, what better way to embarrass and discredit the United States than to make a smiling public appearance? In fact, not only has bin Laden not emerged from hiding since his (alleged) killing in May, but al-Qaeda itself publicly acknowledged that bin Laden was killed.

The fact that al-Qaeda has denied that America had any role in the attacks strikes a heavy blow to the already shaky credibility of the “Truther” movement and other 9/11 conspiracy theorists. They must not only explain the stark lack of evidence implicating the American government in the attacks, but also explain why America’s longtime sworn enemy would deny U.S. involvement if it were true.

Read more at Discovery News

Astrophysicists Share Nobel -- and a Mystery

A trio of relatively young astronomers won the prestigious Nobel Prize for Physics today, not for solving a problem, but for making an observation: our universe is expanding faster now than it did in the past.

Whoever figures out why this is happening likely will get a Nobel of his or her own -- plus the one just awarded to 41-year-old astronomer Adam Riess, with Johns Hopkins University and the Space Telescope Science Institute in Baltimore.

"It's a very juicy problem," Riess told reporters on a conference call. "It's hard and you'll win a Nobel Prize if you figure it out. In fact, I’ll give you mine."

The leading theory for the universe's accelerating girth is an anti-gravity force called dark energy, but that's pure speculation at this point. New observatories providing deep and wide views of the universe will help, but what is really needed to resolve the puzzle is a new conceptual framework.

"At best we will get some clues about the nature of dark energy (from observations) but we won’t really resolve it until some brilliant person, the next Einstein-like person, is able to get the idea of what's going on and we can test that idea," Riess told Discovery News.

Riess shares the 2011 Nobel Prize in Physics with University of California-Berkeley astrophysicist Saul Perlmutter, who headed a rival team looking at the same phenomena, and with American-Australian Brian Schmidt, 44, a professor of astronomy at the Australian National University, who worked with both teams.

"It’s going to be a huge job for us to get to the bottom of what's going on here," Perlmutter, who turned 52 last week, tells Discovery News.

Evidence, which is still being collected, comes from measuring the brightness of exploding stars called supernova, which emit roughly the same amount of light wherever and whenever they're found. If you know you're looking at 100-watt light bulb, for example, you can tell how far away it is based on how much of the light you can see. From the observations of supernovae, scientists were able to determine that the universe is expanding at a faster rate now than it did in its younger days.

Perlmutter's team began by observing the rate of expansion of the distant universe and comparing it with today's acceleration. Riess' team worked from present day, back to the past. During presentations of research papers at science conferences, they came to realize that they were both making the same bizarre findings, so while there was competition, there also was comfort that the weirdness was not an error in instrument, technique or judgment.

Read more at Discovery News

Doomsdays That Never Happened

Last week, the mischievous eggheads of Improbable Research -- which publishes the mock journal Annals of Improbable Research, among other activities -- gathered at Harvard University's Sanders Theater to award the annual Ig Nobel Prizes in honor of scientific achievement that first makes you laugh, and then makes you think.

It's kind of a dubious honor to receive an Ig Nobel: some scientists are tickled by the prospect, like physicist Andre Geim, who won in 2000 for his research on levitating frogs. Others? Not so much. But a few recipients always show up for the ceremony to accept their prizes, regardless. Such was not the case for the winners of this year's Ig Nobel Mathematics Prize, awarded to:

    Dorothy Martin of the USA (who predicted the world would end in 1954), Pat Robertson of the USA (who predicted the world would end in 1982), Elizabeth Clare Prophet of the USA (who predicted the world would end in 1990), Lee Jang Rim of KOREA (who predicted the world would end in 1992), Credonia Mwerinde of UGANDA (who predicted the world would end in 1999), and Harold Camping of the USA (who predicted the world would end on September 6, 1994 and later predicted that the world will end on October 21, 2011), for teaching the world to be careful when making mathematical assumptions and calculations.

Making predictions about the end of the world as we know it is pretty much a stock in trade for crackpots; expect to hear a rising chorus of panicked doomsday prophets next year as we move inevitably towards Dec. 21, 2012 and the end of the Mayan calendar -- plus a nifty planetary alignment (the Earth, the sun and the center of the Milky Way galaxy) that, as Neil de Grasse Tyson is more than happy to tell you, occurs every year:

Unusual planetary alignments are a common culprit when it comes to doomsday prophecies (along with comets or asteroids). The technical term is syzgy, and it narrowly refers to a three-body system -- usually the sun, the earth, and either the moon or another planet in the solar system that is either in conjunction or opposition to the other bodies.

But in the broader sense, it's applied to any unusual conjunction of planets. The term might be familiar to fans of The X-Files; it was the title of an early episode in the series, where a key plot rested on an unusual planetary alighment.

So these kinds of predictions are common; they're also usually wrong, and this year's motley collection of Ig Nobel doomsday prophets is no exception. I suppose they can take comfort in the fact that they're in very good company. Here's just a sampling of famous failed Doomsday predictions from eras past, most of which sought to place the blame squarely on the cosmos.

2800 B.C. One of the earliest known Doomsday Predictions was inscribed on an acient Assyrian clay tablet. Loosely translated, it read, "Our earth is degenerate in these latter days. There are signs that the world is speedily coming to an end. Bribery and corruption are common."

February 1, 1524. London astrologers were convinced that odd planetary activity would give rise to a second Great Flood, causing 20,000 residents to panic and flee to higher ground.

1881. A 16th-century British prophetess named Mother Shipton supposedly wrote that the world would end in 1881, although the publisher of said prophecy, one Charles Hindley, later admitted he made the whole thing up to sell more books.  That didn't stop Scottish astronomer Charles Piazzi Smyth from finding "clues" in the Great Pyramids of Giza indicating the world would indeed end in 1881.

May 18, 1910. This date marked the return of Halley's Comet, along with the usual doomsday fears -- in this case, the suspicion that the human race would be wiped out by noxious gases in the comet's tail.  When Halley's comet swung by Earth on April 29, 1987, doomsday prophet Leland Jensen predicted a collision between it and the Earth that would lead to mass extinction. He, too, was wrong. Coincidental side note: author Mark Twain -- born in 1835, another Halley's Comet year -- correctly "predicted" he would die when the comet returned in 1910. Sometimes the universe just likes to mess with you.

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Oct 3, 2011

Powerful Chile Telescope Opens its Eyes

A much anticipated telescope has finally opened its eyes. And, oh, the wonders it can see...

The very first images from the Atacama Large Millimeter/submilimeter Array, or ALMA, have been released to the public today. With just this first image, the potential of the new instrument to peer into the darkest and most exciting recesses of the universe can be seen. And the telescope hasn't even begun.

In the picture above, we can see a multi-wavelength composite of the galaxies NGC4038 and NGC4039, better known as the Antennae. The white and pink are from Hubble Telescope data, the blue from the radio emission seen by the Very Large Array, and the yellow and orange the new contributions from ALMA. The Antennae are a pair of spiral galaxies in the process of smashing together.

When galaxies collide, no stars collide due to their immense distances from each other, but gas can collide, igniting one of the grandest fireworks displays in the cosmos.

New stars are born, burn brightly, and die in fantastic supernovae in the span of just tens of millions of years. The complex process of star formation itself, however, is still a great puzzle for astronomers to piece together.

This is one area where ALMA will shine. Millimeter and submillimeter wave radiation can penetrate the thick, obscuring dust that surrounds the forming stars in the earliest stages. In the image below, the yellow and orange represents the emission seen by ALMA, tracing star formation even where the visible light image shows only a dark region.

Though an impressive amount of science has been done with previous mm/sub-mm telescopes, they lacked the sensitivity and ability to see fine details. They laid the groundwork whereas ALMA will be the first major workhorse telescope in these bands.

Observing at these wavelengths is very challenging because of the amount of water in Earth's atmosphere. Water absorbs and distorts the mm/sub-mm light coming from space, so astronomers had to go to the high desert region of the Chilean Andes in order to build this telescope. When completed, it will have 66 individual antennas working as one complete telescope using one of my favorite techniques ever, interferometry.

Though it can take a lot of work to produce an image from a radio interferometer, especially one with so many challenges from the atmosphere, ALMA has been designed to calibrate for weather effects and eventually have a pipeline process for data so that astronomers new to radio astronomy can get science-quality data for their work with little tweaking.

I should note, also, that ALMA's power is not only in imaging but in spectroscopy. The light collected by ALMA can be spread out by frequency (or wavelength, depending on your tastes) where tons and TONS of emission lines can be seen from molecules in space. The identities of many of these molecules are unknown, so ALMA will be like a chemistry lab for the universe as well, with its own set of tools.

On a personal note, I've been hearing about ALMA since I was a wee undergrad just getting into this radio astronomy business. I heard it discussed while I was a summer student at MIT's Haystack Observatory in 2003, and a little more when I got my first internship at the National Radio Astronomy Observatory (NRAO), the organization contributing the US share of the telescope's development.

I even visited the three test antennas out in New Mexico when they were decided on final designs. Now, I live and work in Charlottesville, home of the North American ALMA Science Center at NRAO headquarters. I've seen engineers designing and building special receivers for the telescopes at the NRAO Technology Center. We even have a joke amongst the grad students that no astronomer can give a talk in Charlottesville without mentioning ALMA somewhere in the talk!

So, yeah, though I've been watching from the sidelines, I am thrilled to see this come to fruition after the dedicated hard work of so many people for so long.

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Beheaded Archbishop's Face Revealed

The face of a 14th-century former Archbishop of Canterbury has been revealed 630 years after he was beheaded by angry peasants.

Resembling a character out of a science fiction movie, the medieval cleric Simon of Sudbury now stares at visitors in St. Gregory's Church at Sudbury in Suffolk, where the 3-D model is on permanent display alongside the original skull.

"There was a gasp when people saw what he looked like as his sculpture was unveiled. He was compared to characters such as Spock and Shrek, and some were surprised by the size of him. Indeed, he is quite a big guy," forensic artist Adrienne Barker from the University of Dundee told Discovery News.

Simon of Sudbury, who was Chancellor of Salisbury and Bishop of London before becoming Archbishop of Canterbury in 1375, crowned King Richard II at Westminster Abbey in 1377.

Named Lord Chancellor of England three years later, the mild and gentle archbishop soon became the target of the peasants' hatred.

Seen as responsible for introducing the third poll tax, Simon met a grisly end when insurgents stormed the Tower of London during the Peasants' Revolt, or the Great Rising of 1381. They dragged him from his chamber to Tower Hill, struck off his head and placed it on a spike on Tower Bridge.

It is believed that the gruesome trophy was spotted by a man from Sudbury, who grabbed it in the middle of the night and brought it back to his hometown in a barrel of brine.

While the archbishop's body was buried in Canterbury Cathedral, the head has been kept at St. Gregory's Church at Sudbury in Suffolk ever since.

To reconstruct the archbishop's face, Barker first carried out CT scans on his partly mummified skull.

The scans provided grim details about the execution.

"The CT images showed evidence of only one blow, which would have cut through the neck tissue at least halfway and would have severed the cervical spinal nerve 4, causing respiratory arrest," Barker said.

"This is not to say that there weren't more blows; however these would have occurred to tissues we no longer had access to," she added.

Barker, who created a website detailing how the reconstruction worked step by step, made use of known measurements of the thickness of soft tissue at key areas on human faces.

Once a cast of the skull was produced, she stuck in wooden pegs cut to the lengths of the desired tissue thickness on the corresponding points of the skull.

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Beetles Die During Sex With Beer Bottles

Besotted beetles are dying while trying to get it on with discarded brown beer bottles, according to research conducted by Darryl Gwynne, a University of Toronto Mississauga professor.

It's a case of mistaken attraction, because the beer bottles happen to possess all of the features that drive male Australian jewel beetles wild. They're big and orangey brown in color, with a slightly dimpled surface near the bottom (designed to prevent the bottle from slipping out of one's grasp) that reflects light in much the same way as female wing covers.

As a result, the beer bottles are irresistible to the male insects, which will die trying to mate with them in the hot Australian sun.

Gwynne made these observations with colleague David Rentz. This week they were awarded with an Ig Nobel Prize at Harvard University.

The Ig Nobel Prizes, a parody of the Nobel Prizes, are awarded annually by the scientific humor magazine Annals of Improbable Research to first make people laugh and then make them think." The prizes are intended to celebrate the unusual, honor the imaginative and spur people's interest in science, medicine and technology.

"I'm honored, I think," Gwynne, who is a professor of biology, was quoted as saying in a press release. "Really, we've been sitting here by the phone for the past 20 plus years waiting for the call. Why did it take them so long?"

Gwynne and Rentz were conducting field work in Western Australia when they noticed something unusual along the side of the road.

He explained, "We were walking along a dirt road with the usual scattering of beer cans and bottles when we saw about six bottles with beetles on top or crawling up the side. It was clear the beetles were trying to mate with the bottles."

The bottles –- stubbies as they are known in Australia, Canada and a few other countries –- resemble a "super female" jewel beetle. Male beetles are so captivated by the bottles that they will gird their loins and go through the expected motions, refusing to leave until they fry to death, are consumed by hungry ants, or are physically removed by the researchers.

The male beetles are very particular about the bottles. Beer cans or wine bottles do nothing for them. It's all about the shape, color, and texture, and doesn't have anything to do with booze. As the researchers wrote, "Not only do western Australians never dispose of a beer bottle with beer still in it, but many of the bottles had sand and detritus accumulated over many months."

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Oct 2, 2011

Getting Intimate with a Black Hole Behemoth

Black holes have captured our imagination and fascination since they were first hinted to exist in the universe. People love to ask about black holes, how they work, how we know they are there.

My favorite black holes are the monsters that live in the centers of most galaxies where they have the potential to make themselves known through powerful processes that can be seen across the universe.

Active galactic nuclei, or AGNs, are the bright, sometimes chaotic, always powerful regions around a supermassive black hole that is eating up the surrounding material. How massive? Try millions, even billions of times the mass of our sun, which is something like 300,000 times the mass of our whole planet. So yeah, "behemoth" doesn't even begin to describe it.

So far, we know that when material gets pulled into a black hole, it is gone from the observable universe for good. So, how can we see so much activity in an AGN? Well, not all of the material makes it in, and the stuff that does sure can make its presence known beforehand.

Astronomers have been plugging away at describing the details of these regions for decades, figuring out all the complex balances of radiation pressure and gas pressure and turbulent velocities and rotational velocities and so much more. Yet, the complex puzzle has yet to be solved.

No wonder it's taken a team of 26 astronomers on four continents to get the latest, finest probe of the AGN of a galaxy called Markarian 509.

This "test case" went under extreme scrutiny by 5 different space telescopes in order to probe the finer effects of the supermassive black hole on its surroundings. The AGN was monitored in visible, x-ray, and gamma-ray wavelengths with the European Space Agency's XMM-Newton and INTEGRAL satellites.

Astronomers go to such high frequencies when studying AGN because these show where some of the most energetic processes are happening. After monitoring in this way for six weeks, they acquired deep observations with two of the best imaging telescopes in space, the Hubble Space Telescope and Chandra X-Ray Observatory. To top it off, the satellite Swift monitored the galaxy at several wavelength through the whole campaign.

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Dead Sea Not Quite Dead Yet

The Dead Sea is not really dead. Freshwater springs are still feeding the rapidly drying body of water.

A collaborative team of researchers from Ben-Gurion University of the Negev in Israel and the Max Planck Institute of Marine Microbiology in Germany used highly skilled divers to observe the springs and undersea life. The scientists knew the springs and the organisms that grew around them were there, but they has never been able to observe them directly.

"While researchers have known for decades that the 'Dead' Sea was a misnomer, the rich variety of life as evidenced in the vicinity of the springs was unexpected," said Danny Ionescu of the Max Planck Institute in a press release.

"While there are no fish present, carpets of micro-organisms that cover large seafloor areas contain considerable richness of species," Ionescu said.

"The micro-organisms in the Dead Sea water mainly belong to the domain Archaea and they number around 1,000 to 10,000 per milliliter, much lower than regular sea water," said Ionescu. "Never before have microbial mats/ biofilms been found in the Dead Sea and not much is known about sediment micro-organisms in the Dead Sea."

The Dead Sea itself is dying. The salty sea has been shrinking by about three feet per year because its main source of fresh water, the Jordan River, is used to give drinking water to Israelis, Palestinians, and Jordanians. The famous Jordan River, site of Jesus' baptism, is siphoned off just below the Sea of Galilee.

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