Science & TechnologyS


Magic Wand

Pigeons never forget a face


Society for Experimental Biology
Sat, 02 Jul 2011 13:02 UTC
Image
© Ahmed BelguermiUntrained feral pigeons have special skills enabling them to recognize individuals, and are not fooled by people changing clothes
New research has shown that feral, untrained pigeons can recognise individual people and are not fooled by a change of clothes.

Researchers, who will be presenting their work at the Society for Experimental Biology Annual Conference in Glasgow on Sunday the 3rd of July, have shown that urban pigeons that have never been caught or handled can recognise individuals, probably by using facial characteristics.

Although pigeons have shown remarkable feats of perception when given training in the lab this is the first research showing similar abilities in untrained feral pigeons.

In a park in Paris city centre, pigeons were fed by two researchers, of similar build and skin colour, wearing different coloured lab coats. One individual simply ignored the pigeons, allowing them to feed while the other was hostile, and chased them away. This was followed by a second session when neither chased away the pigeons.
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Life Preserver

NASA research offers new prospect of water on Mars


Physorg
Sun, 03 Jul 2011 06:34 UTC
NASA scientists are seeing new evidence that suggests traces of water on Mars are under a thin varnish of iron oxide, or rust, similar to conditions found on desert rocks in California's Mojave Desert.
Water in Mars
© NASA

Mars could be spotted with many more patches of carbonates than originally suspected. Carbonates are minerals that form readily in large bodies of water and can point to a planet's wet history. Although only a few small outcrops of carbonates have been detected on Mars, scientists believe many more examples are blocked from view by the rust. The findings appear in the Friday July 1, online edition of the International Journal of Astrobiology.

"The plausibility of life on Mars depends on whether liquid water dotted its landscape for thousands or millions of years," said Janice Bishop, a planetary scientist at NASA's Ames Research Center at the SETI Institute at Moffett Field, Calif., and the paper's lead author. "It's possible that an important clue, the presence of carbonates, has largely escaped the notice of investigators trying to learn if liquid water once pooled on the Red Planet."

Scientists conduct field experiments in desert regions because the extremely dry conditions are similar to Mars. Researchers realized the importance of the varnish earlier this year when Bishop and Chris McKay, a planetary scientist at Ames investigated carbonate rocks coated with iron oxides collected in a location called Little Red Hill in the Mojave Desert.
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Info

Scientists Crack Secret To Mysterious Tibetan Singing Bowls


redOrbit
Sat, 02 Jul 2011 14:55 UTC
Tibetan Singing Bowl
© redOrbit

Scientists have cracked the secret to what makes Tibetan "singing bowls" so mysterious.

The water-filled bowls are rubbed with a leather-wrapped mallet to exhibit a haunting sound, creating strange waves.

A Tibetan bowl is generally made from a bronze alloy containing copper, tin, zinc, iron, silver, gold and nickel.

The Faraday waves arise when a fluid like water vibrates, constrained by a closed boundary like the edge of the bowl.

As the frequency of the rubbing reaches at which the bowl naturally vibrates, the bowl's edge begins rhythmically to change shape, from one slightly oval shape into another.

The energy of this shape-shifting partly transfers to the water, in which a range of interesting patterns can arise as the intensity of the rubbing increases.

However, at a certain point the water becomes unstable, which results into a fizzing display of droplets and chaotic waves.
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Bizarro Earth

Astronomers Study "Zombie" Stars


United Press International
Thu, 30 Jun 2011 17:24 UTC
Image
© NASA/Chandra X-ray ObservatoryThis is a Chandra X-ray image of Tycho's supernova remnant. This Type Ia supernovae was observed by Tycho Brahe in 1572, and today is just an expanding ball of gas.
Santa Barbara, California - U.S. astronomers say they are studying so-called "zombie stars" that explode as they die only to come back from the dead by sucking matter out of other stars.

The phenomenon happens all the time in the universe, they say, but a study of zombie stars could aid astronomers and physicists in their search for so-called dark energy, which is thought to make up about three-fourths of the universe and which scientists believe is related to the expansion of the universe.

"We only discovered this about 20 years ago by using Type Ia supernovae, thermonuclear supernovae, as standard or 'calibrated' candles," Andy Howell, professor of physics at the University of California, Santa Barbara said. "These stars are tools for measuring dark energy. They're all about the same brightness, so we can use them to figure out distances in the universe."

Howell calls Type Ia supernovae "zombie" stars because they're dead, with a core of ash, but they come back to life by sucking matter from a companion star, a UCSB release said Thursday.

Astrophysicists are using Type Ia supernovae to study the history of the universe's expansion.
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Alarm Clock

Galaxy classification is out of tune, say astronomers

Colin Stuart
Physicsworld.com
Fri, 01 Jul 2011 04:51 UTC
Image
© UnknownHave some galaxies been misclassified?
The way galaxies have been classified for decades has been questioned by an international team of astronomers. After revealing that two-thirds of local elliptical galaxies are actually fast-spinning discs, the team has suggested that the Hubble "tuning fork" - the long-standing method for classifying galaxies - may need retuning.

Galaxies come in all shapes and sizes: from flat spinning discs to almost-stationary blob-like elliptical galaxies. However, accurately classifying these huge objects can sometimes be tricky due to the angle from which they are observed. When seen face-on, older disc galaxies that have lost their distinctive dust lanes and spirals can masquerade as equally featureless, but spherical, elliptical galaxies. Elliptical galaxies are thought to have very little net rotation whereas disc galaxies rotate much faster. Measuring their rotation speed can therefore help distinguish between them.
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2 + 2 = 4

A Paradigm-Shattering Quasar

Shweta Krishnan
Skyandtelescope.com
Sat, 02 Jul 2011 04:20 UTC
Image
© ESO/M. KornmesserThis artist’s impression shows how ULAS J1120+0641, a very distant quasar powered by a black hole with a mass two billion times that of the Sun, may have looked. This quasar is the most distant yet found and is seen as it was just 770 million years after the Big Bang. It is by far the brightest object yet discovered in the early universe.
Using a host of powerful telescopes, a team of European astronomers has discovered an extremely luminous quasar that existed as early as 770 million years after the Big Bang. At a redshift of 7.085, this object is now the most distant known quasar. The previous record holder is at a redshift of 6.4.

The team led by Daniel Mortlock and Stephen Warren (Imperial College, London) published its findings in Thursday's issue of Nature. According to the paper, the quasar's spectrum shows signatures of gases that fogged the early universe, and offers scientists a unique opportunity to study the events that altered the composition of the early cosmos.

At the heart of the quasar, however, lies a conundrum. The black hole that powers it is a monster. With a mass of two billion suns, it strains currently accepted theories on black-hole formation and evolution.
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Ark

US: 4,517 Bones Found At Colorado Ice Age Fossil Site


TheDenverChannel.com
Fri, 01 Jul 2011 12:53 UTC
snowmass dig
© 7News

Snowmass Village -- Crews are racing against time to finish the dig at an Ice Age fossil site near Aspen.

Excavation began at the site last fall after a bulldozer operator uncovered a bone while working on an expansion of Ziegler Reservoir. Work stopped for the winter but resumed in mid-May.

Crews are finishing work this weekend before construction on the reservoir resumes next week.

During the last seven-week dig, crews found 4,517 bones from at least 20 different kinds of Ice Age animals, according to the Denver Museum of Nature and Science.
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2 + 2 = 4

Bringing Prehistoric Colors Back to Life

Michael Balter
Sciencemag.org
Thu, 30 Jun 2011 16:15 UTC
Image
© R. A. Wogelius et al., ScienceEarly bird. A chemical scan of the 125-million-year-old Confuciusornis (artist's conception) reveals traces of its ancient pigments.
What colors were the first birds? Our avian friends appeared about 150 million years ago, and some prehistoric bird fossils have been found with their feathers nearly intact. But the colors faded away long ago, leaving paleontologists in the dark about the original hues. Now a research team employing state-of-the-art chemical imaging has found traces of the plumes' ancient pigments. The new techniques might eventually tell scientists not only what colors prehistoric birds sported but also why they evolved highly pigmented plumage in the first place.

Today's birds display a panoply of colors: Robins have orange breasts, canaries are usually yellow, and blackbirds - well, despite the name, they often mix basic black with bright hues of yellow and red. Ornithologists think birds evolved these colors to attract mates, camouflage themselves from predators, and recognize fellow members of their species in the crowded sky. Very recently, scientists have been able to detect pigment-containing granules, called melanosomes, in some very early bird fossils, as well as in their immediate ancestors, the dinosaurs. And they have made educated guesses about the color of the pigments in the melanosomes based on the granules' sizes and shapes.
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Eye 2

Prehistoric animals had great sight: Australian researchers


Xinhua
Thu, 30 Jun 2011 08:20 UTC
Australian researchers on Thursday said they discovered that prehistoric animals had excellent sight.

Scientists from the South Australian Museum and the University of Adelaide examined a 515 million-year-old fossilized eyes found on Kangaroo Island of South Australia, and found that the prehistoric animals had "compound eyes" with more than 3,000 lenses each.

This means that some of the earliest animals had very powerful eyesight with similar vision to living creatures today.

The team concluded that sharp vision must have evolved very rapidly soon after the first predators appeared 540 million years ago.

According to University of South Australia paleontologist Dr. Jim Jago, he was surprised to find complex eyes, like those of living insects, in such primitive animals.

"It was a fluke, to be honest," he said in a statement released on Thursday.
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Info

Why Faces of Other Races Look Alike

Remy Melina
Live Sceince
Fri, 01 Jul 2011 13:00 UTC
Face Recognition
© Yuri Arcurs | Dreamstime.comThe amplitude of increased brain activity only predicts whether an other-race face, not a same-race face, will be remembered, the study suggests.

The brain works differently when memorizing the face of a person from one's own race than when attempting to remember the face of someone of another race, new biological evidence suggests.

The well-documented "other-race effect" finds that people are less likely to remember a face from a racial group different from their own. Northwestern University researchers set out to determine what causes this rift in perception and memory by using electroencephalogram (EEG) recordings, which measure brain activity, while participants viewed photos of various faces.

The researchers found that brain activity increases in the very first 200 to 250 milliseconds when seeing both same-race and other-race faces. Previous research has associated this very early phase, known as the N200 brain potential, with the perceptual process of individuation. That process involves making out the unique facial features of each person, such as the shape of their eyes and nose.
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