Apr 16, 2011

Moth Mutation Explains Classic Example of Evolution

The molecular mechanics behind a classic example of evolution that dates back to Darwin’s time may soon be revealed.

As soot from coal-fired factories blackened trees and buildings in 19th-century England, naturalists noticed that peppered moths were also trading in their light-colored wings sprinkled with black specks for a sleek, all-black stealth-bomber look known as the carbonaria form. Within a few decades of their first appearance near Manchester, the black moths dominated, making up 90 percent or more of the peppered moth population in local urban areas.

Biology textbooks often cite peppered moths as a classic example of adaptation to changing environmental conditions. The trouble is, no one really knew which molecular changes led the moths to switch wing color. It was an open debate whether the change, which presumably allowed moths to blend better into the increasingly grimy background and avoid bird predators, was due to one mutation or many, and if the adaptation occurred once or several times.

Now, researchers led by Ilik Saccheri, an ecological geneticist at the University of Liverpool in England, report online April 14 in Science that they have traced the mutation responsible for the funereal look to a single page in the moth’s genetic instruction book. That page is a region of a chromosome that contains genetic instructions for creating color patterns on wings in butterflies and other related species. This region of the butterfly and moth genome is an adaptation hot spot — one in which mutations produce hundreds of different wing-color patterns in many species, including variations that allow edible butterfly species to mimic foul-tasting species, and mutations that control the size of eyespots on butterfly wings.

“The fact that the carbonaria mutation maps to the same region as butterfly-wing-pattern genes is amazing,” says Robert D. Reed, an evolutionary developmental biologist at the University of California, Irvine, who was not involved in the study. “Presumably it takes hundreds of genes to make a wing pattern, so why does this region appear over and over again?”

As yet, no one has identified the precise DNA changes that lead to the hundreds of different color patterns, but scientists are actively scouring the region for the pattern-changing mutations.

Likewise, Saccheri and his colleagues don’t yet know which genes or regulatory elements are altered by the carbonaria mutation. What they do know is that the black moths they collected from 80 sites in the United Kingdom share some key genetic signposts, suggesting that the carbonaria mutation involves only one spot in the genome and happened just once, probably shortly before the first reported sightings in 1848 near Manchester.

“I think we have fairly strong evidence that industrial melanism in the U.K. was seeded by a single recent mutation,” Saccheri says. That might not settle the matter, though. “Until we find the causal mutation it’s still open to some debate.”

Peppered moths in continental Europe and the eastern United States also went dark during the industrial revolution. Saccheri does not know if those moths have mutations in the same region as the British moths or if mutations elsewhere produced the same color pattern.

Read more at Wired Science

First Signs of Lake Life Having Sex on the Beach

A vacation lake trip can involve plenty of party time, taking in the sun’s rays, as well as a lot of shore-side romance if the weather is nice.

Early life was taking in the sun and looking for love in lakes too. One billion year old fossilized microorganisms from Scotland’s Loch Torridon had complex structures that made photosynthesis and sexual reproduction possible.

What makes these early eukaryotic fossils important is that they came from what was once a lakebed. Evolution of specialized structures in the cell, like the nucleus, mitochondria, and chloroplasts, had originally been thought to occur only in the oceans.

These Scottish fossils had all the biological equipment for enjoying a day of sex and sunbathing. The nucleus is vital for containing genetic information and facilitates sexual reproduction. The chloroplasts allow organisms to turn sunlight into usable energy.

"It may even be that the sort of conditions found in the ancient lakes around Loch Torridon favored a key step in this transformation, which involved the incorporation of symbiotic bacteria into the cell to form chloroplasts, rather than this occurring in the sea as usually envisaged,” said Martin Brasier of the University of Oxford in a press release from the University of Sheffield.

Brasier was one of the authors of a paper published in Nature detailing the ancient Scottish lake-dwellers. He worked with a team of scientists from Boston College, University of Sheffield, and the University of Oxford, to uncover the fossils from rocks near Loch Torridon on the west coast of Scotland.

Cell_pairs_160"During this time the continents are often considered to have been essentially barren of life - or at the most with an insignificant microbial biota dominated by cyanobacteria. We have discovered evidence for complex life on land from 1 billion year old deposits from Scotland,” said Charles Wellman of the University of Sheffield in a press release by that school.

Some of the fossils found were from organisms living in the lake, but others were from organisms living on land that were washed into the lake and fossilized.

“This suggests that life on land at this time was more abundant and complex than anticipated. It also opens the intriguing possibility that some of the major events in the early history of life may have taken place on land and not entirely within the marine realm," said Wellman.

The fossils from the Scottish lake lived during an important time when simple celled organisms called prokaryotes, such as cyanobacteria, were evolving into more complex organisms called eukaryotes. Prokaryotes lack many of the structures that allow more advanced life to use resources from their environment, like sunlight.

Read more at Discovery News

Mind tricks may help arthritic pain

BBC: A chance discovery by academics in Nottingham has found that a simple optical illusion could unlock a drug-free treatment for arthritis.

The computer-generated mind trick has been tested on a small sample of sufferers and found that in 85 per cent of cases it halved their pain.

Research is still in the early stages, but initial results suggest the technology, called Mirage, could help patients improve mobility in their hands by reducing the amount of pain they experience.

For the illusion to work patients place their hand inside a box containing a camera, which then projects the image in realtime onto a screen in front of them.

The subject then sees their arthritic fingers being apparently stretched and shrunk by someone gently pushing and pulling from the other side of the box.

Full Story at BBC

Apr 15, 2011

Scientists create human kidneys from stem cells

TELEGRAPH: The artificial organs were created in a laboratory using human amniotic fluid and animal foetal cells.

They are currently half a centimetre in length – the same size as kidneys found in an unborn baby.

Scientists at Edinburgh University hope they will grow into full-size organs when transplanted into a human.
The breakthrough could lead to patients creating their own replacement organs without the risk of rejection, a common complication in transplant procedures.

Physiologist Jamie Davies, a professor of experimental anatomy at Edinburgh University, said: ”It sounds a bit science fiction-like but it’s not.

”The idea is to start with human stem cells and end up with a functioning organ.

”We have made pretty good progress with that. We can make something that has the complexity of a normal, foetal kidney.”

The research team hope that doctors will eventually be able to collect amniotic fluid, which surrounds the growing embryo in the womb, when a baby is born.

This will then be stored by scientists in case that person develops kidney disease later in life. The fluid can then be used to create a matching kidney.

Creating an organ using a patient’s own stem cells solves the problem of having to use powerful immunosuppressant drugs to stop the body rejecting a another person’s kidney.

Professor Davies said the technology could be ready for use on humans in around 10 years.

Apr 14, 2011

Language like people came out of Africa

Using sophisticated analysis of hundreds of languages, the researchers have managed to trace back their beginnings to the same place and the same time.

They now believe that language may have been one of the "tools" that boosted humanity and led to the colonisation of the whole planet.

"We think that this language was a stepping stone in civilisation which led to better co-ordination and co-operation that might have led us to expand," said Dr Quentin Atkinson, at the University of Auckland and Oxford University.

"It could have also led to competition that would have given us a push."

Dr Atkinson analysed 504 languages to see how many phonemes – particular sounds – they contained.

To his surprise he found a direct correlation between the age of the civilisation and the number of phonemes in its language.

So while many African languages had more than 100 phonemes, Hawaiian language had as few as 13. English, French and German had about 45 each.

The analysis, which used the World Atlas of Language Structure as the main resource, relies on the theory that older civilisations have picked up more linguistic diversity as they age – from genes to language.

It then used this to extrapolate back the origins of language to Africa.

It pinpointed the time as around 150,000 years ago as this was when cave art – one of the earliest forms of communication – began.

It is thought that early man then left Africa around 80,000 years go – taking with him some of the diversification but not all of it.

In general, the areas of the globe that were most recently colonised incorporate fewer phonemes into the local languages whereas the areas that have hosted human life for millennia still use the most phonemes, the report concluded.

Read more at The Telegraph

Apr 13, 2011

Secret FBI File Exposes Roswell UFO -- Or Not?

The UFO blogosphere has been burning up over the past few days with news about a recently-discovered Top Secret FBI file proving that flying saucers and alien bodies were recovered in Roswell, New Mexico, in 1947.

The information, which appears in an apparently genuine FBI file, is being called the real deal. One (typical) blogger crowed that the "FBI secret memo says Roswell flying saucers were legit."

The March 22, 1950 document from Washington bureau agent Guy Hottel to the director of the FBI, has the subject line "Flying Saucers, Information Concerning," and states that:

"An investigator for the Air Forces stated that three so-called flying saucers had been recovered in New Mexico. They were described as being circular in shape with raised centers, approximately 50 feet in diameter. Each one was occupied by three bodies of human shape but only 3 feet tall, dressed in metallic cloth of a very fine texture. Each body was bandaged in a manner similar to the blackout suits used by speed flyers and test pilots. According to Mr. [blacked out] informant, the saucers were found in New Mexico due to the fact that the Government has a very high-powered radar set-up in that area and it is believed the radar interferes with the controlling mechanism of the saucers."

Is it a hoax? Or final proof that flying saucers and their alien occupants are on ice somewhere in Area 51? The Sun newspaper ran a story headlined, "Aliens exist, say real-life X-files," and quoted a UFO expert named Nick Pope as saying, "These are the real life X-Files. This document could be the smoking gun that proves UFOs are real."

Or it could be the smoking gun that proves that Pope and many journalists didn’t look at the document very closely.

First of all, the supposedly "secret document" is instead a non-classified, ordinary office memo. This seems odd given the supposedly explosive nature of its contents; you might think that the FBI would do a better job of making sure that anyone in the office wouldn't have access to a document admitting that they are hiding three crashed saucers and nine alien bodies. The memo has also been known about for years.

Second, Roswell is not mentioned anywhere in the memo. It merely says the saucers were "recovered in New Mexico." Since the alleged saucer crash in Roswell, New Mexico, is the most famous in the world, it’s easy to assume that it’s referring to Roswell. However, none of the Roswell eyewitnesses described "flying saucers...circular in shape with raised centers, approximately 50 feet in diameter," nor nine, three-foot tall aliens wearing metallic cloth space suits.

Instead, the informant’s words match a description given in a proven UFO hoax in Aztec, New Mexico, a year after the supposed Roswell incident. David Thomas, a New Mexican physicist and UFO researcher, found exactly that story was spun by a con man named Silas Newton and an accomplice, who fabricated a UFO crash hoax as part of a scam. Newton was arrested in 1952 and convicted of fraud in connection with the UFO hoax.

Read more at Discovery News

Dead cow and a car engine amongst strangest items checked-in to fly

A car engine, a dead cow and bag of sand and sea water are among the strangest items that air passengers have tried to check in on flights.

One lady even turned up at a JFK airport check-in desk with family members carrying her bath. It wasn’t even wrapped or packaged.

Check-in staff at Virgin Atlantic were also presented with a giant wheel of cheese and a tarantula hidden in a lady’s coat, according to a survey by the airline from its 32 flying locations.

Other passengers tried to check-in a bag of cutlery stolen from a previous Virgin Atlantic flight at Delhi Airport.

For those who couldn’t quite let go of their holiday there was a a couple who fell in love on the island of Grenada and decided to try and check in a bag full of sand, sea and water as a memory from the island.

Greg Dawson, Director of Corporate Communications commented: “Virgin Atlantic check in staff see thousands of passengers on a daily basis but every now and then, a passenger will arrive at check in with something you would never expect – it certainly brightens up their day.”

Read more at The Telegraph

Old wives' tales: true or false?

Eating carrots will make you see in the dark: FALSE

But if you eat too many carrots they could turn you orange. Carrots — along with yellow and green veg and citrus fruits — contain carotene. Eat enough and you get "carotenaemia" — an orangey colouration most noticeable in the palms and soles.

The belief that carrots can help eyesight dates back to the Second World War when the Royal Air Force was trying to hide the fact it had developed a sophisticated radar system to shoot down German bombers. The RAF claimed the accuracy of its fighter pilots at night was a result of them being fed carrots.

Eating crusts makes your hair curl: FALSE

Curly hair grows from curly follicles, and straight hair from straight follicles. But eating crusts is good for you. They are rich in compounds called melanoidins which help to produce more of the 'good' bacteria we need for healthy guts. Melanoidins also increase the amount of enzymes, thought to protect against cancer.

Wait an hour after eating before swimming: FALSE.

Digestion diverts some blood from the muscles but for ordinary swimming they should get enough oxygen to avoid cramp.

Most body heat is lost through the head: FALSE.

Only about ten per cent of heat is lost through the head.

Drink at least eight glasses of water a day: FALSE.

Hydrating the body can be achieved with most liquids, including tea and coffee.

Feed a cold, starve a fever: FALSE.

In both cases you should drink lots of fluids and eat healthily.

Read more at The Telegraph

Apr 12, 2011

Physicists Build Big Bang in a Box

Sitting on a bench at the University is Maryland is the first-ever desktop model of the Big Bang.

Don’t worry — the 20-micrometer-wide device simulates how light behaved and time flowed at the universe’s spark, not the explosion itself. It could someday help explain why time marches in only one direction.

“What we have done, with simple experimental geometry, is reconstruct the way that space-time expands,” said Igor Smolyaninov, who describes the model in a paper submitted to Physical Review Letters.

Smolyaninov and Yu-Ju Hung, both electrical engineers at the University of Maryland, made their Big Bang simulation from exotic substances called metamaterials, which use alternating slices of different materials to twist light in unusual ways.

Researchers have suggested using metamaterials as invisibility cloaks that bend light around objects, to disguise one object as another and to build a perfect lens. A few years ago, physicists realized that metamaterials can also mimic astronomical events: a planet orbiting a star, light being trapped in black holes.

Building a toy cosmos in the lab lets physicists run otherwise impossible experiments on the nature of space and time. With Smolyaninov and Hung’s setup, researchers could study the thermodynamic arrow of time, a longstanding problem in physics.

Most physical laws work just as well whether time runs forwards or backwards, but not the second law of thermodynamics. It dictates that disorder must always increase with time. That’s why people can’t age backwards, eggs can’t become uncracked, and Groundhog Day is fiction.
‘What we have done, with simple experimental geometry, is reconstruct the way that space-time expands.’

Another exception is the “cosmological arrow of time,” which points forward from the Big Bang in the direction of the universe’s expansion. This arrow could be linked to the thermodynamic arrow and point toward the ultimate heat death of the universe, but it could also someday reverse if the universe collapses in a “Big Crunch.”

“While it is generally believed that the statistical and the cosmological arrows of time are connected, we cannot replay the Big Bang and prove this relationship in the experiment,” the researchers write. But with a metamaterial Big Bang on the lab bench, they can.

To build their desktop Big Bang, the researchers arranged strips of acrylic and gold so that laser light hitting the gold excites waves of free electrons called plasmons. The math describing their path through the metamaterials’ flat surface is the same as math describing how massive particles move through a flat version of  Minkowski space, which contains dimensions for both space and time.

Read more at Wired Science

Limb Regrowth Now Possible in Some Mammals

The day when mammals and perhaps humans could regrow limbs is soon approaching as scientists near a breakthrough.

The first phases of limb regeneration observed in some amphibians, echinoderms and many plants has been replicated in mice for the first time, according to new research featured in the journal ACS Chemical Biology.

The project represents the first time scientists have replicated these beginning stages of limb regeneration in mammals.

Essentially, the process is somewhat similar to stem cell differentiation. Rather than unspecialized cells turning into specialized cells such as heart and skin cells, there's another step.

In a process called "dedifferentiation," specialized cells such as those found in bone muscle turn into unspecialized cells and then change again into another type of specialized cell different than what they started as.

In the experiment, scientists applied a combination of chemicals to skeletal muscle in mice tissue in hopes of creating dedifferentiation. Specifically, this included using compounds called "small molecules" and altering a promoter, or a range of DNA that controls a specific gene.

After applying the treatment to the skeletal muscle cells, researchers were able to coax cells into changing into fat and bone cells, which play a large role in the early stages of limb regeneration.

With more research, it's plausible that the technique could benefit humans and mammals that lost limbs in accidents.

Read more at Discovery News

Priceless Egyptian Treasures Returned

A statue of King Tutankhamun, which was looted during Egypt's anti-government protests, has been returned to the Egyptian Museum in Cairo along with three other pharaonic artifacts, Zahi Hawass, Minister of State for Antiquities, announced today.

Stolen when vandals and looters broke into the Cairo museum during the January revolution that brought down President Hosni Mubarak, the statue, cataloged as JE 60710.1, is one of three gilded wooden statues of King Tutankhamun that were declared missing in March (the official list of the items that were stolen from the Egyptian museum included a total of 63 objects).

Statue of Tutankhamun, missing from the Egyptian Museum since January, showing its condition upon its return. (Photo by Rania Galal)

Showing the boy king standing in a boat and throwing a harpoon, the statue suffered a minor damage.

"A small part of the crown is missing as well as pieces of the legs. The boat is still in the museum, and the figure of the king will be reunited with it and restored," Hawass, who was named minister of antiquities last month, said in a statement.

Two other objects were returned to the Tutankhamun collection.

Read more at Discovery News

Apr 11, 2011

Mythbuster Developing U.S. Military Armor

MythBusters Adam Savage and Jamie Hyneman (photo) have a reputation for blending the nutty professor's scientific method with the daredevil's lust for pyrotechnic hijinks. They've debunked many a schoolyard myth and urban legend on their popular television show, and done it all with Christmas-morning glee. In the name of science they've fired cheese out of canons, driven cars off cliffs and even lit a match head with a bullet fired from a .45 caliber pistol.

Wacky experiments aside, the dynamic duo's technical, up-close-and-personal work with TNT and C4 explosives has garnished the attention of the U.S. government, debunking the myth that playing with dynamite leads to a dead-end career.

Because of his explosive resume and MythBusters' idiosyncratic settings, Jamie Hyneman has recently been working with the Office of Naval Research to develop lightweight armor for U.S. military vehicles in Iraq and Afghanistan.

"We had a lot of experience in the show dealing with explosives, obviously in ways and situations that are outside the norm. This is very revealing, because when you see something outside the norm you get to see what the boundaries of the phenomenon are," Hyneman told The Register.

"I'd looked at those and formed a lot of questions in my head. When I saw the opportunity to do research on a topic, I got very active and applied a lot of what I'd learned on the show."

Hyneman's task was to devise an ultra-lightweight armor that wouldn't weigh-down vehicles, but was still strong enough to withstand shrapnel and blast damage from powerful improvised explosive devices (IED's) while protecting those inside the vehicle from the blast's pressure wave.

Read more at Discovery News

Apr 10, 2011

Commodore 64 is back with a revamp

For those of a certain age it will evoke glorious memories of wasted afternoons playing Donkey Kong, International Karate and Pitfall: The Commodore 64 is coming back, albeit with something of an upgrade.

While the familiar clunky beige box is all present and correct, replete with rainbow logo, inside things have changed somewhat.

The new C64 comes kitted out as a modern-day PC, running Linux but capable of handling the Windows 7 operating system. It's hardware has also been given a boost - it sports a 1.8 gigahertz processor (rather more powerful than the original's 1 megahertz), built in Wi-Fi, and a DVD player.

When it was first launched in 1982, the Commodore 64 was a massive hit and was arguably the first computer to bring gaming to the mass market by undercutting rivals Atari and Apple on price. It came with a then-massive 64 kilobytes of memory and included an integrated graphics card - all the better for displaying those wondrous 16 colours in all their glory.

It could be plugged into the television set for home gaming and could also be set up with higher quality monitor for more serious applications. It's 2011 revival, however, comes with an HDMI cable for high-definition output. The basic version is to be sold for $595, the same price as the original.

In the UK the C64's only serious rival was the Sinclair ZX Spectrum (remember mashing those rubbery keys to Daley Thompson's Decathalon?) but the C64's superior power saw it overtake its rivals towards the end of the 1980s.

The C64 has been rescued from history by a group which has bought the rights to both the Commodore and AMIGA brand names, and has plans to reboot the AMIGA too at some point.

Read more at New Scientist

Mysterious Cosmic Blast Keeps on Going

Astronomers have witnessed a cosmic explosion so strange they don’t even know what to call it. Although the blowup, discovered with NASA’s Swift satellite on March 28, emits high-energy radiation like a gamma-ray burst would, the event has now lasted for 11 days. Gamma-ray bursts last for an average of about 30 seconds.

Also unlike a gamma-ray burst, the explosion has faded and brightened, emitting staccato pulses of energetic radiation lasting for hundreds of seconds.

“It’s either a phenomenon we’ve never seen before or a familiar event that we’ve never viewed in this way before,” says Andrew Fruchter of the Space Telescope Science Institute in Baltimore. The outburst might have been generated by a star torn to shreds when it ventured too close to a black hole in its host galaxy, he suggests. Gas from the star falling into the black hole could have triggered the gravitational monster to emit a jet of X-rays and gamma rays that by chance happens to point directly at Earth.

A radio-wavelength image taken May 29 along with a Hubble Space Telescope image taken in visible light on April 4 supports that model. The images show that the explosion took place 3.8 billion light-years from Earth, at the center of a galaxy where a supermassive black hole would lie. It’s also possible that the star might have been ripped apart by a smaller black hole, Fruchter notes.

“Tidal disruption of a star by a black hole seems very plausible,” says Andrew MacFadyen of New York University. The blast’s duration “is much longer than anything we’d naturally expect from [explosive] collapse of a single star,” which is the traditional model for producing a gamma-ray burst, he says.

Read more at Wired Science