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You’ve got to see it to be it. A heightened sense of red color vision arose in ancient reptiles before bright red skin, scales and feathers, a new study suggests. The finding bolsters evidence that dinosaurs probably saw red and perhaps displayed red color.

The new finding, published in the Aug. 17 Proceedings of the Royal Society B, rests on the discovery that birds and turtles share a gene used both for red vision and red coloration. More bird and turtle species use the gene, called CYP2J19, for vision than for coloration, however, suggesting that its first job was in sight.
“We have this single gene that has two very different functions,” says evolutionary biologist Nicholas Mundy of the University of Cambridge. Mundy’s team wondered which function came first: the red vision or the ornamentation.

In evolution, what an animal can see is often linked with what others can display, says paleontologist Martin Sander of the University of Bonn in Germany, who did not work on the new study. “We’re always getting at color from these two sides,” he says, because the point of seeing a strong color is often reading visual signals.

Scientists already knew that birds use CYP2J19 for vision and color. In bird eyes, the gene contains instructions for making bright red oil droplets that filter red light. Other forms of red color vision evolved earlier in other animals, but this form allows birds to see more shades of red than humans can. Elsewhere in the body, the same gene can code for pigments that stain feathers red. Turtles are the only other land vertebrates with bright red oil droplets in their eyes. But scientists weren’t sure if the same gene was responsible, Mundy says.

His team searched for CYP2J19 in the DNA of three turtle species: the western painted turtle, Chinese soft-shell turtle and green sea turtle. All three have the gene. Both birds and turtles, the researchers conclude, inherited the gene from a shared ancestor that lived at least 250 million years ago. (Crocodiles and alligators, close relatives of birds and turtles, probably lost the gene sometime after splitting from this common ancestor, Mundy says.)

Next, the scientists turned their attention to the gene’s function. Mundy’s team studied western painted turtles, which have a striking red shell. As in red birds, CYP2J19 is active in the eyes and bodies of these turtles, the scientists found, suggesting that the gene is involved in both vision and coloration.
Because most birds and turtles can see red, but only some have red feathers or scales, the researchers think the great-granddaddy of modern turtles and birds probably used the gene for vision, too. Whether that common ancestor was colored red is unclear.

That very old reptile would have passed CYP2J19 down to its descendants, including dinosaurs. Mounting evidence has pointed to dinosaurs as colorful, with good color vision. But the specifics of their coloration have been elusive. This study points to red as one color they could probably see, and perhaps display.

“If you would have asked me 10 years ago, ‘Will we ever know the color of dinosaurs?’” Sander says, “I would have said, ‘No way!’” But studies like this one are a new lens into dinosaur color. Seeing can mean displaying, and this study is solid evidence that dinosaurs saw red, Sander says. In the past, “we couldn’t really say that.”

These orderly patterns of dark blue dots indicate where individual chlorine atoms are missing from an otherwise regular grid of atoms. Scientists manipulated these vacancies to create a supersmall data storage device.

The locations of vacancies encode bits of information in the device, which Sander Otte of Delft University of Technology in the Netherlands and colleagues describe July 18 in Nature Nanotechnology. The team arranged and imaged the vacancies using a scanning tunneling microscope. The storage system, which can hold a kilobyte of data, must be cooled to a chilly −196° Celsius to work.
To demonstrate the technique, the researchers transcribed an excerpt from a famous 1959 lecture by physicist Richard Feynman, “There’s Plenty of Room at the Bottom,” which predicted the importance of nanotechnology. In each block, paired rows represent letters. Blocks marked with an “X” were unusable. The encoded 159 words of text fill a region a ten-thousandth of a millimeter wide.

If scaled up, the researchers say, the technology could store the full contents of the U.S. Library of Congress in a cube a tenth of a millimeter on each side.

Plastic cling wrap with nano-sized pores could give “cool clothes” a new meaning.

The material lets heat escape, instead of trapping it like traditional fabrics, Stanford University materials scientist Yi Cui and colleagues report in the Sept. 2 Science. It could help people keep cool in hot weather, Cui says, and even save energy by reducing the use of air conditioning.

“It’s a very bold new idea,” says MIT physicist Svetlana Boriskina, who wrote an accompanying commentary. Demand for the new material could be far-reaching, she says. “Every person who wears clothes could be a potential user of this product.”
Current cooling devices include wearable fans and wicking fabrics; both rely on evaporation to cool human skin. But skin also sheds heat in another way — as infrared radiation. Clothing holds this heat close to the body, Cui says. If infrared radiation could instead pass through fabric, he reasoned, people would feel a lot cooler.

But the fabric would have to be transparent only to infrared wavelengths. To visible light, it would need to be opaque. Otherwise, the clothing would be see-through.

Cui found just one material that satisfied both requirements: a commercially available plastic used in lithium-ion batteries. The material, called nanoporous polyethylene, or nanoPE, is a cling wrap‒like plastic that lets infrared radiation through. But unlike cling wrap, the material isn’t clear: It blocks visible light.

Tiny pores speckled throughout the fabric act as obstacles to visible light, Boriskina says. When blue light, for example, hits the pores, it scatters. So do other colors. The light “bounces around in different directions and scrambles together,” she says. To human eyes, the resulting color is white.

The pores scatter visible light because they’re both in the same size range: The diameters of the pores span 50 to 1,000 nanometers, and the wavelengths of visible light range from 400 to 700 nanometers. Infrared light emitted by the body has a much larger wavelength, 7,000 to 14,000 nanometers, so the plastic’s tiny pores can’t block it. To infrared light, the pores are barely bumps in the road, not barriers.
The pores are kind of like small rocks at a beach, Boriskina says. They’ll interfere with the motion of small waves, but big waves will wash right over.

Cui and colleagues tested nanoPE by laying it on a hot plate warmed up to human skin temperature — 33.5° Celsius. NanoPE raised the “skin” temperature by just 0.8 degrees(to 34.3° C). “But when you put on cotton, my God, it rose to 37,” Cui says. “It’s hot!”

The researchers also tried to make nanoPE more wearable than plastic wrap. They coated it with a water-wicking chemical, punched holes in it to make it breathable, and layered it with cotton mesh. Now, the team is working on weaving the fabric to make it feel more like traditional textiles.

“Within five years, I hope someone will start wearing it,” Cui says. “And within 10 years, I hope most people will be wearing it.”

Researchers have digitally unwrapped and read an ancient Hebrew scroll that’s so charred it can’t be touched without falling apart. It turns out the document contains the oldest known Biblical text outside of the roughly 2,000-year-old Dead Sea Scrolls, the investigators say.

Archaeologists discovered the scroll’s remnants in a synagogue’s holy ark during a 1970 excavation in Israel of En-Gedi, a Jewish community destroyed by fire around 600.

In a series of digital steps, slices from a 3-D scan of the En-Gedi scroll were analyzed to bring letters and words into relief on a pieced-together, virtual page. Those images revealed passages from the book of Leviticus written in ink on the scroll’s disintegrating sheets. Radiocarbon results date the scroll to approximately 300, making it the earliest copy of an Old Testament book ever found in a holy ark, scientists report September 21 in Science Advances.

This computerized recovery and conservation process can now be used to retrieve other ancient documents “from the brink of oblivion,” the researchers say.

DENVER — A period of skyrocketing global temperatures started with a bang, new research suggests.

Impact debris and evidence of widespread wildfires around eastern North America suggest that a large space rock whacked Earth around 56 million years ago at the beginning of the Paleocene-Eocene Thermal Maximum, also known as the PETM, a period of rapid warming and huge increases in carbon dioxide. The event is one of the closest historic analogs to modern global warming and is used to improve predictions of how Earth’s climate and ecosystems will fare in the coming decades.
Too little is known about the newfound impact to guess its origin, size or effect on the global climate, said geochemist Morgan Schaller of Rensselaer Polytechnic Institute in Troy, N.Y. But it fits in with the long-standing and controversial proposal that a comet impact caused the PETM. “The timing is nothing short of remarkable,” said Schaller, who presented the discovery September 27 at the Geological Society of America’s annual meeting.

The impact may have contributed to the rapid rise in CO2 by stirring carbon up into the atmosphere, but it was hardly the sole cause, said Sandra Kirtland Turner, a geochemist at the University of California, Riverside. Her own environmental simulations suggest that the influx of carbon that flooded Earth during the PETM probably took place over at least 2,500 years, far too drawn out to be caused by a single event, she said at the same meeting.

During the PETM, a massive influx of carbon flooded the atmosphere (SN: 5/30/15, p. 15) and Earth warmed by 5 to 8 degrees Celsius to temperatures much hotter than today. That carbon dump altered the relative abundance of different carbon isotopes in the atmosphere and oceans, leaving a signal in the sedimentary record.

While searching for that signal in roughly 56-million-year-old sediments from sites up and down the U.S. East Coast, Schaller spotted microscopic glassy spheres about the size of a dust mite. These specks resemble those blasted from previously identified large impact events. After switching from a black to a white sorting tray to more easily see the black debris, one of Schaller’s Rensselaer colleagues, micropaleontologist Megan Fung, discovered abundant charcoal pieces in the mix. That charcoal formed when wildfires sparked by the impact raged across the landscape, she proposed.

More evidence of the impact will help researchers to better constrain its location, scope and possible relationship to the start of the PETM, Schaller said.

Condensing billions and billions and billions of years into a 45-minute film is a tall order. But director Terrence Malick took on the challenge with Voyage of Time. The film, now playing in IMAX theaters, surveys the 13.8-billion-year history of the universe and even looks eons into the future when we — life on Earth, the planet and the entire solar system — are gone.

Starting with the Big Bang, Voyage of Time progresses through highlights of the past, with a central focus on the evolution of life. Malick, best known for directing visually rich dramas such as The Thin Red Line and The Tree of Life, presents breathtaking cinematography, using locales such as Hawaii’s lava-oozing Kilauea volcano as stand-ins for the past. Stunning visualizations and special effects bring to life the formation of the planets, the origin of the first cells, the demise of the sun and other events that scientists can only imagine.
The film marks Malick’s first attempt at documentary filmmaking. If you can call it that. Viewers hoping for a David Attenborough–style treatment of the subject matter will be disappointed. The film is more evocative, with moody scenes that provide little explication. And what narration (by Brad Pitt) there is tends to be philosophical rather than informative.

Serious science enthusiasts may find some reasons to quibble with the movie. For one, it’s hard to grasp the true immenseness and scale of cosmic time. With so much screen time devoted to the evolution of life, many viewers may not realize just how relatively recent a phenomenon it is. After the Big Bang, more than 9 billion years passed before Earth began to form. It took many hundred thousand more years before the first microbes emerged.
Malick’s treatment of evolution may also rankle some viewers. At times, the narration seems to imply life was destined to happen, with the young, barren Earth just waiting around for the first seeds of life to take root. At other times, the narration imbues evolution with purpose. Pitt notes, for instance, that perfecting a leaf took eons. Yet perfection is something evolution neither achieves nor strives for — it’s a process that lacks intentionality.

These critiques aside, Malick sought to tell an accurate story, enlisting an accomplished group of scientists as advisers, including Lee Smolin of the Perimeter Institute for Theoretical Physics in Waterloo, Canada. Smolin says he was impressed with the end result. “It’s a very unusual film,” he says, likening it to a visual poem or piece of art.

And that’s probably the best mindset to watch Voyage of Time: Just sit back, soak in the dazzling visuals and contemplate the wonders of nature.

Two more teeny moons might be lurking around Uranus. That’s in addition to the 27 we already know about. Fluctuations in the density of two of the planet’s dark rings, seen in radio data from the 1986 flyby of the Voyager 2 spacecraft, could be caused by unseen moonlets, Robert Chancia and Matthew Hedman, astronomers at the University of Idaho in Moscow, report online October 9 at arXiv.org.

At probably just 4 to 14 kilometers wide, both moons would be very difficult to detect in Voyager 2 images, the researchers report. New observations with ground-based telescopes might have better luck.

Traffic jams in the brain’s blood supply may play a role in Alzheimer’s disease. A new online game turns people at home into amateur traffic cops. This policing, which involves spotting hard-to-see sluggishness in tiny capillaries in mice, may ultimately help scientists better understand, and perhaps even treat, Alzheimer’s, a devastating disorder that affects over 5 million Americans.

The science behind the game, called Stall Catchers, comes from Cornell University. Chris Schaffer, Nozomi Nishimura and colleagues found that mice designed to exhibit symptoms similar to Alzheimer’s have more blocked blood vessels in their brains than regular mice. That difference can deprive the brain of sustenance and may be a key to understanding how Alzheimer’s damages the brain, the researchers suspect.
But finding congested capillaries is a slog. Computers haven’t been up to snuff, and experts could spend an entire year analyzing the thousands of microscope images needed to amass enough data to explore links between Alzheimer’s and blocked vessels. “I thought, if we could change that, it would be tremendous,” says Pietro Michelucci, director of the Human Computation Institute in Fairfax, Va. The institute is a nonprofit organization that runs the EyesOnALZ program, which aims to crowdsource Alzheimer’s research.

That’s where StallCatchers.com comes in. The website asks players to sift through short black-and-white videos of real mouse brains, on the prowl for blocked blood vessels. In the videos, moving blood appears white. But stationary black segments that appear between two white segments signal trouble — a stall. Players rack up points and ascend levels as they classify vessels. With practice, the task gets easier. And people who suffer from performance anxiety shouldn’t fret; each video will be scrutinized by multiple users to get the final verdict. With a little help from the crowd, “not only do [researchers] get answers faster, but they can ask more questions,” Michelucci says.

So far, nearly 1,000 users have played Stall Catchers, Michelucci says. Those players are beginning to generate data that will let researchers see how good these amateur traffic cops are. With luck, their eyes will help unstall the fight against Alzheimer’s.

NEW ORLEANS — Popular heartburn drugs — already under investigation for possible links to dementia, kidney and heart problems (SN: 6/11/16, p. 8) — have a new health concern to add to the list. An analysis of almost 250,000 medical records in Denmark has found an association with stroke.

Researchers from the Danish Heart Foundation in Copenhagen studied patients undergoing gastric endoscopy from 1997 to 2012. About 9,500 of all patients studied suffered from ischemic strokes, which occur when a blood clot blocks a blood vessel in the brain.

Overall, the risk of stroke was 21 percent higher in patients taking a proton pump inhibitor, a drug that relieves heartburn, the researchers reported November 15 during the American Heart Association’s annual meeting. While those patients also tended to be older and sicker to start with, the level of risk was associated with dose, the researchers found. People taking the lowest drug doses (between 10 and 20 milligrams a day, depending on the drug) did not have a higher risk. At the highest doses, though, Prevacid (more than 60 mg/day) carried a 30 percent higher risk and Protonix (more than 80 mg/day) a 94 percent higher risk. For Prilosec and Nexium, stroke risk fell within that range.

Introduced in the 1980s, proton pump inhibitors are available in both prescription and over-the-counter forms. While they are valuable drugs, “their use has been increasing rapidly,” says lead author Thomas Sehested, adding that people often take them for too long, or without a clear reason. Before taking them, he says, “patients need a conversation with their doctor to see if they really need these drugs.”

These skeletons are spilling their guts about the size of the body cavity that housed these animals’ stomach and intestines.

Using digital 3-D scans of mounted skeletons, researchers estimated the body cavity volume in 126 species. Of the 76 mammal species, plant eaters had bigger bellies; their relative torso volumes were about 1.5 times as large as those of carnivores, researchers report online November 4 in the Journal of Anatomy.

The study is the first to quantitatively test the long-held idea that herbivores have bigger torsos, says Marcus Clauss of the University of Zurich. Plant eaters are thought to need extra space for complex systems that digest a leafy diet.
Surprisingly, Clauss and colleagues didn’t find the same pattern in nonavian dinosaurs, birds or reptiles, but the researchers had fewer skeletons to compare. Of the 27 dinosaurs, for example, only four were carnivores.

Still, the research suggests that in tetrapods — four-limbed vertebrates — only mammalian herbivores have larger body cavities, raising questions about why that might be evolutionarily. “Everybody goes crazy about the long neck or the strange things” on an animal’s head, Clauss says. But few scientists have focused on the torso’s frame and how diet helps sculpt it over time. “This study emphasizes that the torso is an important part of overall body shape.”