Eyes are windows to the soul—and evolution

Why do we become saucer-eyed from fear and squint from disgust?These near-opposite facial expressions are rooted in emotional responses that exploit how our eyes gather and focus light to detect an unknown threat, according to a study by a Cornell University neuroscientist.

Our eyes widen in fear, boosting sensitivity and expanding our field of vision to locate surrounding danger. When repulsed, our eyes narrow, blocking light to sharpen focus and pinpoint the source of our disgust.

The findings by Adam Anderson, professor of human development in Cornell's College of Human Ecology, suggest that human facial expressions arose from universal, adaptive reactions to environmental stimuli and not originally as social communication signals, lending support to Charles Darwin's 19th century theories on the evolution of emotion.

"These opposing functions of eye widening and narrowing, which mirror that of pupil dilation and constriction, might be the primitive origins for the expressive capacity of the face," said Anderson. "And these actions are not likely restricted to disgust and fear, as we know that these movements play a large part in how perhaps all expressions differ, including surprise, anger and even happiness."

Anderson and his co-authors described these ideas in the paper, "Optical Origins of Opposing Facial Expression Actions," published in the March 2014 issue ofPsychological Science.

Looks of disgust result in the greatest visual acuity—less light and better focus; fearful expressions induce maximum sensitivity—more light and a broader visual field.

"These emotions trigger facial expressions that are very far apart structurally, one with eyes wide open and the other with eyes pinched," said Anderson, the paper's senior author. "The reason for that is to allow the eye to harness the properties of light that are most useful in these situations."

What's more, emotions filter our reality, shaping what we see before light ever reaches the inner eye.

"We tend to think of perception as something that happens after an image is received by the brain, but in fact emotions influence vision at the very earliest moments of visual encoding."

Anderson's Affect and Cognition Laboratory is now studying how these contrasting eyemovements may account for how facial expressions have developed to support nonverbal communication across cultures.

"We are seeking to understand how these expressions have come to communicate emotions to others," he said. "We know that the eyes can be a powerful basis for reading what people are thinking and feeling, and we might have a partial answer to why that is."

Source phys.org

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Big Bang: Einstein's relativity theory backed by new-wave discovery

In the first moment following the Big Bang, scientists believe the universe got very big, very quickly.

On Monday, US astronomers said they had peered further back in time than ever before and detected compelling evidence of this dramatic and rapid expansion, a theory known as ''cosmic inflation''.

''It is somewhat of a mad theory, which was introduced in the 1980s to solve a lot of issues with the way the universe looked,'' said University of Melbourne cosmologist Alan Duffy.
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''This discovery is really the first confirmation that a trillionth of a trillionth of a second after the Big Bang the universe grew enormously,'' he said. ''We're all pretty ecstatic about this result.''

The announcement is also significant because it provides proof for Einstein's final prediction, the theory of general relativity, which predicts a violent event such as the rapid expansion of the universe would create ripples in space-time called gravitational waves.

After using a radio telescope at the South Pole, a team from the Harvard-Smithsonian Centre for Astrophysics said it had detected very specific patterns of light, known as B-modes, which were almost certainly caused by very early gravitational waves as a result of cosmic inflation.

''We're very excited to present our results because they seem to match the prediction of the theory so closely,'' said John Kovac, the leader of the BICEP project.

While strong circumstantial evidence existed for gravitational waves, no one had observed them directly, which was why the detection of light patterns left by primordial gravitational waves had astronomers so excited.

If the result was verified it promised to be one of the biggest advances in cosmology in 20 years, comparable to Australian Nobel prize winner Brian Schmidt discovering the expansion of the universe was accelerating. It also had implications for scientist's understanding of quantum mechanics.

University of Sydney astrophysicist Bryan Gaensler said normally the effect of gravitational waves was so small it was extremely difficult to detect.

But the rapid and violent expansion caused by inflation would have set the whole universe ringing with them, he said.

And although these early waves had long disappeared, the theory of inflation predicted they would leave behind a very specific and subtle imprint in the form of B-modes.

Professor Gaensler said scientists had been looking for B-modes for years, but the radio signal they emitted was very faint and travelled from the edge of the universe.

''It's like looking through a really dirty window at something that's thousands of kilometres away,'' he said.

University of Melbourne cosmologist Katie Mack said while the detection of primordial gravitational waves in the early universe was a ''really big deal'' and was consistent with the theory of inflation, their presence alone was not direct evidence of the theory.

''We can't say for sure that those gravitational waves were produced by inflation,'' she said.

But she said their detection was evidence that gravity had quantum mechanical properties, like particles, something physicists suspected but had not seen evidence of.

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A 'chicken from hell' dinosaur: Large feathered dinosaur species discovered in North America

Scientists from Carnegie and Smithsonian museums and the University of Utah today unveiled the discovery, naming and description of a sharp-clawed, 500-pound, bird-like dinosaur that roamed the Dakotas with T. rex 66 million years ago and looked like an 11 ½-foot-long "chicken from hell."
"It was a giant raptor, but with a chicken-like head and presumably feathers. The animal stood about 10 feet tall, so it would be scary as well as absurd to encounter," says University of Utah biology postdoctoral fellow Emma Schachner, a co-author of a new study of the dinosaur. It was published online today in PLOS ONE, a journal of the Public Library of Science.

The study's lead author, Matt Lamanna of the Carnegie Museum of Natural History in Pittsburgh, says: "We jokingly call this thing the 'chicken from hell,' and I think that's pretty appropriate."

The beaked dinosaur's formal name is Anzu wyliei – Anzu after a bird-like demon in Mesopotamian mythology, and wyliei after a boy named Wylie, the dinosaur-loving grandson of a Carnegie Museums of Pittsburgh trustee.

Three partial skeletons of the dinosaur – almost making up a full skeleton – were excavated from the uppermost level of the Hell Creek rock formation in North and South Dakota – a formation known for abundant fossils of Tyrannosaurus rex and Triceratops. The new dinosaur was 11 ½ feet long, almost 5 feet tall at the hip and weighed an estimated 440 to 660 pounds. Its full cast is on display at the Carnegie Museum.

Schachner and Lamanna were joined in the new study and description of three specimens by Hans-Dieter Sues and Tyler Lyson of the Smithsonian Institution's National Museum of Natural History in Washington.

"I am really excited about this discovery because Anzu is the largest oviraptorosaur found in North America," she says. "Oviraptorosaurs are a group of dinosaurs that are closely related to birds and often have strange, cassowary-like crests on their heads." (The cassowary is a flightless bird in New Guinea and Australia related to emus and ostriches.)

Anzu is also "one of the youngest oviraptorosaurs known, meaning it lived very close to the dinosaur extinction event" blamed on an asteroid striking Earth 65 million years ago, Schachner says.

The researchers believe Anzu, with large sharp claws, was an omnivore, eating vegetation, small animals and perhaps eggs while living on a wet floodplain. The dinosaur apparently got into some scrapes.

Source Phys.org

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