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Cows Almost Impossible To Domesticate, DNA Reveals

Domesticated Cow
© iStockPhotoA curious cow.

Cattle aren't known for their intelligence. Perhaps it's because their family tree has a very skinny trunk.

Genetic evidence suggests all "taurine" cattle (the most commonly recognized breed) descend from only about 80 females and came from a single region in what is now Iran about 10,500 years ago. A study in the journal Molecular Biology and Evolution traced the modern global herd's heritage back to its ancestral home on the range.

The study compared mitochondrial DNA extracted from 15 preserved ancient cattle's bones to modern cattle and found little variation. Little variation meant the founding population didn't have many different versions of the mitochondrial genes to start with.

Earlier research published in PloS ONE suggested that taurine cattle may have later received a small genetic boost from European aurochs. Aurochs were the super-sized ancestors of our modern hamburger on the hoof.

The size and nasty disposition of the wild auroch (Bos primigenius) would have made it a formidable beast to tame for the ancient Iranians. That difficulty is possibly why domestication only occurred with a small number of animals. The authors of the paper in Molecular Biology and Evolution suggested that only humans who had settled down into villages would have had the ability to domesticate the auroch.

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Has Modern Science Become Dysfunctional?

DNA
© redOrbit

The recent explosion in the number of retractions in scientific journals is just the tip of the iceberg and a symptom of a greater dysfunction that has been evolving the world of biomedical research say the editors-in-chief of two prominent journals in a presentation before a committee of the National Academy of Sciences (NAS) today.

"Incentives have evolved over the decades to encourage some behaviors that are detrimental to good science," says Ferric Fang, editor-in-chief of the journal Infection and Immunity, a publication of the American Society for Microbiology (ASM), who is speaking today at the meeting of the Committee of Science, Technology, and Law of the NAS along with Arturo Casadevall, editor-in-chief of mBio®, the ASM's online, open-access journal.

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Age of Oldest Rocks off By Millions of Years

Zircon
© Science/AAASZircon gives clues to the past.

Two of the solar system's best natural timekeepers have been caught misbehaving, suggesting that the accepted ages for the oldest known rock samples are off by a million years or more.

According to two new studies, a radioactive version of the element samarium decays much more quickly than previously thought, and different versions of uranium don't always appear in the same relative quantities in earthly rocks.

Both elements are used by geologists to date rocks and chart the history of events on our planet and in the solar system.

"If you have a critical event in Earth's history, something like an extinction event or a climate change shift or a meteorite impact, you need to know the absolute age with the most confidence," says Joe Hiess of the British Geological Survey, who led one of the studies. "In Earth sciences there's a need to be able to define what happened first and what happened second."

Chalkboard

Physicists find patterns in new state of matter

excitons new state of matter physics
© UnknownExcitons self organize into an ordered array that looks like a miniature pearl necklace.
Physicists at the University of California, San Diego have discovered patterns which underlie the properties of a new state of matter.

In a paper published in the March 29 issue of the journal Nature, the scientists describe the emergence of "spontaneous coherence," "spin textures" and "phase singularities" when excitons - the bound pairs of electrons and holes that determine the optical properties of semiconductors and enable them to function as novel optoelectronic devices - are cooled to near absolute zero. This cooling leads to the spontaneous production of a new coherent state of matter which the physicists were finally able to measure in great detail in their basement laboratory at UC San Diego at a temperature of only one-tenth of a degree above absolute zero.

The discovery of the phenomena that underlie the formation of spontaneous coherence of excitons is certain to produce a better scientific understanding of this new state of matter. It will also add new insights into the quirky quantum properties of matter and, in time, lead to the development of novel computing devices and other commercial applications in the field of optoelectronics where understanding of basic properties of light and matter is needed.

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Spectacular Brain Images Reveal Surprisingly Simple Structure

Human Brain
© MGH-UCLA Human Connectome ProjectGrid structure of major pathways of the human left cerebral hemisphere. Seen here are a major bundle of front-to-back paths (the “superior longitudinal fasciculus”, or SLF) rendered in purples. These cross nearly orthogonally to paths projecting from the cerebral cortex radially inward (belonging to the “internal capsule”), shown in orange and yellow. These data were obtained in the new MGH-UCLA 3T Connectom Scanner as part of the NIH Blueprint Human Connectome Project.

Stunning new visuals of the brain reveal a deceptively simple pattern of organization in the wiring of this complex organ.

Instead of nerve fibers travelling willy-nilly through the brain like spaghetti, as some imaging has suggested, the new portraits reveal two-dimensional sheets of parallel fibers crisscrossing other sheets at right angles in a gridlike structure that folds and contorts with the convolutions of the brain.

This same pattern appeared in the brains of humans, rhesus monkeys, owl monkeys, marmosets and galagos, researchers report today (March 29) in the journal Science.

"The upshot is the fibers of the brain form a 3D grid and are organized in this exceptionally simple way," study leader Van Wedeen, a neuroscientist at Harvard Medical School and Massachusetts General Hospital, told LiveScience. "This motif of crossing in three axes is the basic motif of brain tissue."

Sun

MIT Builds 3D Solar Structures Capable of Generating 20 Times Power of Panels

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© MITTwo of the three 3D structures
The improvement in power output comes from the vertical surfaces of the 3D structures

MIT researchers have created new solar designs that stray away from the traditional panel-like shape and instead resemble 3D towers.

Jeffrey Grossman, study leader and Carl Richard Soderberg Career Development Associate Professor of Power Engineering at MIT, along with a team of MIT researchers, constructed 3D solar designs that are vertical and capable of increasing the solar power generated from a certain area.

To do this, the team used a computer algorithm to test a series of possible designs under different conditions regarding weather, seasons and latitudes. Once the predictions were computer generated, the team built three separate models and tested them on the MIT laboratory roof. The structures ranged from simple cube shapes to more complex accordion-type shapes.

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Bottlenose dolphins: 'Gangs' run society, scientists say

Dolphins gangs
© BBCBonded male dolphins mimic each other's behaviour

Male bottlenose dolphins organise gang-like alliances - guarding females against other groups and occasionally "changing sides".

A team studying dolphins in Shark Bay, western Australia, say the animals roam hundreds of square kilometres, often encountering other dolphin groups.

The researchers observed the dolphins there over a five-year period, recording their movements.

They report their findings in the Royal Society journal Proceedings B.

Dr Richard Connor, a researcher from the US who took part in this study, first began his studies of the Shark Bay dolphins in the early 1980s.

This latest study reveals that these highly intelligent marine mammals live in an "open society". Rather than males guarding a specific territory, groups have what Dr Connor described as a "mosaic of overlapping ranges".

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New Layer of Genetic Information Discovered

Ribosomes
© Dale Muzzey/UCSFRepresented here by a tomato and a rope, ribosomes are central to all life on Earth because they help translate genetic information into proteins.

A hidden and never before recognized layer of information in the genetic code has been uncovered by a team of scientists at the University of California, San Francisco (UCSF) thanks to a technique developed at UCSF called ribosome profiling, which enables the measurement of gene activity inside living cells - including the speed with which proteins are made.

By measuring the rate of protein production in bacteria, the team discovered that slight genetic alterations could have a dramatic effect. This was true even for seemingly insignificant genetic changes known as "silent mutations," which swap out a single DNA letter without changing the ultimate gene product. To their surprise, the scientists found these changes can slow the protein production process to one-tenth of its normal speed or less.

As described today in the journal Nature, the speed change is caused by information contained in what are known as redundant codons - small pieces of DNA that form part of the genetic code. They were called "redundant" because they were previously thought to contain duplicative rather than unique instructions.

This new discovery challenges half a century of fundamental assumptions in biology. It may also help speed up the industrial production of proteins, which is crucial for making biofuels and biological drugs used to treat many common diseases, ranging from diabetes to cancer.

"The genetic code has been thought to be redundant, but redundant codons are clearly not identical," said Jonathan Weissman, PhD, a Howard Hughes Medical Institute Investigator in the UCSF School of Medicine Department of Cellular and Molecular Pharmacology.

"We didn't understand much about the rules," he added, but the new work suggests nature selects among redundant codons based on genetic speed as well as genetic meaning.

Similarly, a person texting a message to a friend might opt to type, "NP" instead of "No problem." They both mean the same thing, but one is faster to thumb than the other.

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Eye-Tracking Computers Will Read Your Thoughts

Eye Tracking
© ThinkStockIn the future, will we be served online ads based on the thoughts reflected in our eye movements?

Consider, for a moment, the following list: Republican. Abortion. Democrat. Future. Afghanistan. Health care. Same-sex marriage.

There is an enormous amount of information reflected in the way you just read that list. Did your eyes pause for a fraction of a second on certain words? Did your pupils dilate, ever so slightly, at any point while you were reading the list? For some words did your eyes blink at a different rate? Did you backtrack to reread any words, and if so, which ones, when, and for how long?

Eye-tracking, which uses images from one or more cameras to capture changes in the movements and structure of our eyes, can measure all of these things with pinpoint accuracy. There are many benevolent applications for eye-tracking, most notably in providing disabled people with a way to interact with objects on a screen. But recent advances are taking the technology into the mainstream, with the biggest initial applications likely to be in user interfaces and gaming.

Apple, for example, has filed a patent application for a three-dimensional, eye-tracking user interface, and European company Sensye aims to have its eye-tracking software built into smartphones next year. As eye-tracking becomes increasingly deployed in laptops, tablets, and smartphones in the coming years, it will open a new front in the fractious digital privacy debate.

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Billions of Habitable Worlds in Our Galaxy?

Gliese 667 C
© ESO/L. CalçadaArtist's impression of a sunset from the super-Earth Gliese 667 Cc. The brightest star in the sky is the red dwarf Gliese 667 C, which is part of a triple star system.

Take the most common type of star in the Milky Way -- so-called red dwarf stars that are cooler, smaller and longer-lived than stars like the sun.

Then, survey a sampling for orbiting planets and extrapolate the results. What do you get?

A stunning claim that 40 percent of our galaxy's 160 billion red dwarf stars have plus-sized Earths orbiting the right distance for liquid water to exist on their surfaces, a condition believed to be necessary for life.

If this finding is correct, that would mean the Milky Way is home to tens of billions of planets in habitable zones, concludes a team of scientists using an Earth-based telescope to look for planets beyond the solar system.

The effort is complementary to studies by NASA's Kepler space telescope, which hunts for extrasolar planets around sun-like stars.

About 80 percent of the stars in the Milky Way are red dwarfs, which, on average, are about one-third smaller and 4,000 degrees Fahrenheit cooler than the sun.

Kepler lead scientist William Borucki, with NASA's Ames Research Center in Mountain View, Calif., said he's not surprised by the finding of the European team, which uses a light-splitting spectrograph called HARPS on a telescope at the La Silla Observatory in Chile to look for planets beyond the solar system.

But claiming that red dwarfs' planets are rocky worlds goes too far, Borucki told Discovery News.

"I am astounded that they're saying they are rocky planets. I don't see any reason to assume they're rocky planets," Borucki said.