Oct 15, 2016

Female chimpanzees don't fight for 'queen bee' status

A low-ranking young female chimpanzee was wounded in a fight when she attempted to enter the female social hierarchy.
For wild chimpanzees, social status is more than just a matter of pride. High-ranking chimpanzees of both sexes usually have better access to food and mates, boosting chances of survival for themselves and their offspring.

But male and female chimpanzees achieve social status in dramatically different ways, says a new study by primatologists at Duke University. While males actively challenge their superiors to win higher rank, females accept their position in the social pecking order, waiting until more senior group members die before moving up the ladder.

The study, which appeared online Oct. 14 in the journal Scientific Reports, provides the first detailed look at how social status among wild chimpanzees changes throughout their lifetimes.

"We found that, after entering the adult hierarchy, there was a complete absence of successful challenges for rank increases among females," said Steffen Foerster, senior research scientist at Duke University and lead author on the study. "It's like a formal queue."

Unlike the more gregarious males, female chimpanzees tend to be loners, spending much time by themselves or with their own children. One-on-one encounters between females are generally rare, giving researchers few opportunities to observe signs that would clue them in to each chimpanzee's relative rank.

"For a long time we've been aware that there really are differences in rank between females, but being able to quantify that has been hard because they really don't interact very often," said Duke evolutionary anthropology professor Anne Pusey, who is a senior author on the paper.

To explore how female chimpanzees maneuver up and down the social ladder, Foerster, Pusey and their colleagues plumbed more than 40 years of daily records documenting the behaviors of 100 or so wild chimpanzees residing in Gombe National Park in Tanzania, where Pusey first began working alongside Jane Goodall in 1970.

Chimpanzees signal dominance and submission to each other through acts of aggression, such as chases and attacks, and through making a sound called a "pant-grunt," which is a clear sign of subordination to a superior. The team used a new rating system to document these interactions, allowing them to determine the rank orders of male and female chimpanzees and watch how they shifted over time.

Their results showed that, unlike males, whose rank usually peaks when they reach their prime in their early 20s before declining again, female rank gradually increases as they age, and their rank order remains stable throughout their lifetimes. In addition, though males almost always start their adulthoods at the bottom of the pecking order, the female starting rank varies with each individual.

"That seems to be a crucial moment for them, because after they enter the hierarchy at about 12 years of age, they can't really change anything about their position unless something happens at the top and individuals die," Foerster said.

The team is still investigating how these initial rankings are established, but preliminary evidence indicates that females with mothers in the group seem to have an edge.

Despite the benefits of social status on their reproductive success -- higher-ranking females appear to have access to better food and higher infant survival than their low-ranking counterparts -- the tendency of female chimpanzees to "wait their turn" rather than fighting for rank reveals the competing priorities males and females face when ensuring the success of their offspring.

"If a male has a high rank even for a short time but manages to fertilize a lot of females, he achieves high reproductive success," Pusey said. "Whereas a female is only able to raise one offspring at a time, so her reproductive success depends largely on how long she lives."

Read more at Science Daily

Extinct Wingless Wasp Was Unlike Any Other Insect

A wingless wasp stuck in amber about 100 million years ago is a family unto itself, with no other family like it in insect history. So say Russian, English and American researchers who have written about the evolutionary last-stop insect in a study in the journal Cretaceous Research.

The curious bug, found in Myanmar's Hukawng Valley, had hind legs reminiscent of a grasshopper, antennae like ants, and the abdomen of a cockroach and gave the researchers quite a challenge in determining its taxonomic place.

Finally, though, they decided the insect's face looked closest to a wasp, so they created for it a new family of one, Aptenoperissidae, within the larger Hymenoptera insect order containing wasps and modern bees.

Study co-author George Poinar, Jr., an Oregon State University professor emeritus and expert on amber-encased animals, said he had no idea what kind of bug he was looking at, on first glance.

"You could see it's tough and robust, and could give a painful sting," Poinar, Jr. said in a statement. "We ultimately had to create a new family for it, because it just didn't fit anywhere else."

The amber-entombed insect was a female. Being parasitic, the researchers say she would have spent her time on the ground burrowing into cavities in search of the pupae of other insects in which she could deposit her eggs.

Her long legs, the scientists say, would have helped her climb back out of those burrows.

Such life habits likely played a role in the insect's lack of wings: Going in and out of those tight spaces would have made wings cumbersome.

The wasp was also likely a strong jumper, thanks again to the "grasshopper" legs. Her stinger, meanwhile, was sharp enough for attacking beetles.

For all of those skills, though, the unusual wasp went extinct. The researchers can't say for sure why it did, suggesting disease, loss of habitable living space, and the inability to fly as potential factors.

Whatever the reason, it was literally the end of the line. "When it died out, this created an evolutionary dead end for that family," said Poinar, Jr.

Read more at Discovery News

Oct 14, 2016

T-rays will 'speed up' computer memory by a factor of 1000

The figure shows the spin and lattice structure of thulium orthoferrite (TmFeO?) on the left and the T-ray-induced transitions between the energy levels of thulium ions (Tm³?), which trigger coherent spin dynamics (memory switching), on the right.
Together with their colleagues from Germany and the Netherlands, scientists at the Moscow Institute of Physics and Technology (MIPT) have found a way to significantly improve computer performance. In their paper published in Nature Photonics, they propose the use of the so-called T-waves, or terahertz radiation as a means of resetting computer memory cells. This process is several thousand times faster than magnetic-field-induced switching.

"We have demonstrated an entirely new way of controlling magnetization, which relies on short electromagnetic pulses at terahertz frequencies. This is an important step towards terahertz electronics. As far as we know, our study is the first to make use of this mechanism to trigger the oscillations of magnetic subsystems," says Anatoly Zvezdin of Prokhorov General Physics Institute and MIPT, a coauthor of the paper and a USSR State Prize-winning scientist heading MIPT's Laboratory of Physics of Magnetic Heterostructures and Spintronics for Energy-Saving Information Technologies.

The rapidly increasing amounts of digital data that have to be manipulated, along with the growing complexity of the computation tasks at hand, compel hardware designers to achieve ever higher computational speeds. Many experts believe that classical computation is currently approaching a limit, beyond which no further increase in data processing speed will be practicable. This is motivating scientists all over the world to investigate possibilities of entirely different computer technologies. One of the weak spots in modern computers holding back their evolution is memory: it takes time to complete every set/reset operation for a magnetic memory cell, and reducing the duration of this cycle is a very challenging task.

A group of scientists including Sebastian Baierl of the University of Regensburg, Anatoly Zvezdin, and Alexey Kimel of Radboud University Nijmegen (the Netherlands) and Moscow Technological University (MIREA) proposed that electromagnetic pulses at terahertz frequencies (with wavelengths of about 0.1 millimeters, i.e., between those of microwaves and infrared light) could be used in memory switching instead of external magnetic fields. A more familiar device that makes use of terahertz radiation is the airport body scanner. T-rays can expose weapons or explosives concealed under a person's clothing, without causing any harm to live tissues.

To find out whether T-rays could be used for convenient memory states switching (storing "magnetic bits" of information), the researchers performed an experiment with thulium orthoferrite (TmFeO?). As a weak ferromagnet, it generates a magnetic field by virtue of the ordered alignment of the magnetic moments, or spins of atoms in the microcrystals (magnetic domains). In order to induce a reorientation of spins, an external magnetic field is necessary.

However, the experiment has shown that it is also possible to control magnetization directly by using terahertz radiation, which excites electronic transitions in thulium ions and alters the magnetic properties of both iron and thulium ions. Furthermore, the effect of T-rays proved to be almost ten times greater than that of the external magnetic field. In other words, the researchers have devised a fast and highly efficient remagnetization technique -- a solid foundation for developing ultrafast memory.

Read more at Science Daily

Dense molecular gas disks drive the growth of supermassive black holes: Are supernova explosions the key?

A conceptual rendition of gas being driven into a supermassive black hole following a supernova explosion Strong turbulence caused by supernova explosions inside a dense molecular gas disk in the central region of a galaxy disturbs the stable motion of gas. This causes the gas to flow further inward toward the supermassive black hole at the center.
A joint team of University of Tokyo researchers and their collaborators, using ALMA and other telescopes that utilize radio waves for space observation, revealed that dense molecular gas disks a few hundred light years in scale located at the centers of galaxies supply gas to supermassive black holes situated within them. This finding provides important insights on the growth of supermassive black holes over cosmic time.

Supermassive black holes more than a million times the mass of our sun exist at the centers of many galaxies, but how they came to be is unclear. Meanwhile, a correlation between the rate at which stars form in the central regions of galaxies and the amount of gas that falls into supermassive black holes (mass accretion rate) was known to exist, leading some scientists to suggest that the activity involved in star formation fuels the growth of black holes.

The joint research team led by graduate student and JSPS fellow Takuma Izumi at the Graduate School of Science at the University of Tokyo revealed for the first time -- with observational data collected by ALMA (Atacama Large Millimeter/submillimeter Array), in Chile, and other telescopes -- that dense molecular gas disks occupying regions as large as a few light years at the centers of galaxies are supplying gas directly to the supermassive black holes. The team also succeeded in explaining, with a theoretical model, that the actual changes (balance of inflow and outflow) in gas levels they observed were the result of the increasing amount of gas falling into the supermassive black holes within the gas disks enhanced by strong turbulence generated by supernova explosions (an activity associated with star formation) when a star inside the dense gas disks dies.

Read more at Science Daily

Proxima Centauri Is Like Our Sun... on Steroids

Imagine stepping outside on a clear day and looking up at the sun. However, that isn't our sun; it appears much closer in the sky and, wait, if you squint, you can see there's something not quite right about the light it's emitting. This star appears to have vast, ominous dark patches shimmering against the bright solar disk. That's because this star is Proxima Centauri and, though it sounds like it has a horrible case of rot, these black spots actually make this tiny red dwarf more "sun-like" than we ever imagined.

"If intelligent aliens were living on Proxima b, they would have a very dramatic view," said Brad Wargelin, of the Harvard-Smithsonian Center for Astrophysics (CfA) and lead author of research to be published in the journal Monthly Notices of the Royal Astronomical Society.

Proxima Centauri shot to fame in recent months as the location of the nearest Earth-mass exoplanet to the solar system. Astronomers of the ESO's La Silla Observatory in Chile made the discovery of the Earth-mass world by measuring the "wobble" of the star as the small exoplanet's gravity tugged during its short 11-day orbit. This orbit places Proxima b smack-bang in the middle of Proxima Centauri's "habitable zone" — the distance from a star that is neither too hot or too cold for liquid water to exist on a rocky planet's surface. On Earth, where there's liquid water, there's life.

Exciting as this may sound for the prospect of Proxima b hosting aliens, or even a possible destination for future human colonists, there are some serious problems with assuming Proxima b is even remotely "Earth-like". For starters, we have no clue if the planet has an atmosphere. We also have zero idea as to whether or not the exoplanet possesses water. But another problem for Proxima b is the fact it orbits very close to a star that is known to generate powerful flares, likely drenching any surrounding planets in powerful radiation. Radiation, as we all know, is generally a bad thing for life.

So it may come as a surprise to hear that Proxima Centauri does, actually, have some sun-like qualities. But these qualities probably wouldn't make Proxima b any more "habitable" and actually creates a mystery for solar physicists.

Magnetic Stress

Using ground-based observatories including the All Sky Automated Survey and space telescopes (including NASA's Swift and Chandra missions and the European XMM-Newton observatory) measuring the X-ray emissions from Proxima Centauri, Wargelin's team was able to detect a regular 7-year cycle, which is a little strange.

Proxima Centauri is a tiny, cool star one-tenth the size of our sun. Our sun has a regular "solar cycle" lasting approximately 11 years where magnetic activity will wax and wane. During periods of intense magnetic activity (called solar maximum) in the sun's lower atmosphere (known as the corona), we can expect frequent flares and coronal mass ejections. At this time, the sun's surface can become peppered with dark sunspots, highlighting regions where the sun's inner magnetic field is erupting through the surface (pictured above). Though dramatic, at solar maximum only around 1 percent of the sun's surface will be covered with these blemishes.

After studying Proxima Centauri, however, measurements show that a whopping 20 percent of the tiny star's surface may be covered with very dramatic-looking star spots.

This is interesting on many levels, but it may have exposed a gap in our knowledge of how our own sun works.

The key theory that drives our sun's 11-year cycle is differential rotation. Basically, the sun's upper layer rotates faster at its equator than at the poles. As its magnetic field travels from north to south, it is thought the internal magnetic field at the equator becomes "wrapped" around the sun, like an elastic band being wrapped around a ball. At a certain point, when the magnetic field is at its most stressed (solar max), the pressure is released when the magnetic polarity flips. The sun's magnetic "north" replaces the "south" and vice versa and the cycle begins again.

But red dwarfs like Proxima Centauri aren't thought to possess this uppermost differential rotation layer as they are too small; instead it is thought they experience convection from the core to the uppermost layer (pictured above). Without differential rotation, it's a mystery how Proxima Centauri can have a cycle, let alone a regular 7-year stellar cycle.

Read more at Discovery News

Skin Impression From Europe's 'Last Dinosaur' Found

Some 66 million years ago, a large sauropod dinosaur rested in a patch of mud along a river bank in what is now Spain, leaving behind fossil skin impressions recently found by scientists.

The impressions in the mud were later covered by sand that ultimately petrified into sandstone, forming a relief of the creature's skin as it was at the moment of its rest along the river.

Researchers from the Universitat Autònoma de Barcelona (UAB) and the Institut Catala de Paleontologia Miquel Crusafont (ICP) made the find during a geology expedition in the village of Vallcebre, close to Barcelona. The discovery is unique, they say, thanks to the age of the impressions, which date to the Late Cretaceous, just before dinosaurs went extinct.

UAB researcher Victor Fondevilla, lead author of a study on the find, said in a statement that while other fossilized skin samples of similar vintage have been found, they have only turned up in the United States and Asia. That makes the new skin impressions the vestiges of some of Europe's last dinosaurs.

"This is the only registry of dinosaur skin from this period in all of Europe," Fondevilla said, "and it corresponds to one of the most recent specimens — closer to the extinction event — in all of the world."

The researchers think the scales are too large to have belonged to the typical carnivores or herbivorous hadrosaurs of the day. Instead, they surmise the skin belonged to a large, plant-eating sauropod — "maybe a titanosaurus," said Fondevilla — due to footprints they found from such an animal near the skin impression fossils.

All told, the team found two skin impressions — one 5 centimeters (2 inches) wide, the other 20 centimeters (8 inches) — likely made by the same dinosaur.

"The fact that they are impression fossils is evidence that the animal is from the sedimentary rock period, one of the last dinosaurs to live on the planet," said Fondevilla.

"When bones are discovered," he explained, "dating is more complicated because they could have moved from the original sediment during all these millions of years."

Looking ahead, the skin impressions "represent a valuable tool for analyzing the last occurrences of the sauropod clade before the [mass] extinction," the scientists wrote.

The researchers' findings have been published in Geological Magazine.

From Discovery News

Oct 13, 2016

Our Universe Has 10-20 Times More Galaxies Than Thought

A new headcount of galaxies in the observable universe turned up 10- to 20 times more galaxies than previous estimates, bringing the tally up to as many as 2 trillion, a new study shows.

The missing members of the galactic family tree are most small, dim collections of stars that formed during the universe's early days. Space took up less space back then and the galaxies were crammed together, compared to today's expanded universe.

The Hubble Space Telescope peered long and deep into a small patch of the sky in the mid-1990s, revealing thousands of galaxies stretching back into time. Extrapolating from the analysis, scientists estimated the observable universe is filled with 100 billion- to 200 billion galaxies, said astronomer Christopher Conselice, with the United Kingdom's University of Nottingham.

Now, a new analysis of the Hubble Deep-Field images, combined with other data, shows that estimate is just 10- to 20 percent of the total number of galaxies, most of which are too faint to be seen by present-day telescopes, Conselice and colleagues wrote in a paper to be published in The Astrophysical Journal.

The scientists converted Hubble and other telescopes' images into three-dimensional maps so they could calculate the density of galaxies and estimate the volumes of each successive region of space.

"This painstaking research enabled the team to establish how many galaxies we have missed — much like an intergalactic archaeological dig … The results of this study are based on the measurements of the number of observed galaxies at different epochs — different instances in time — through the universe's history," the University of Nottingham wrote in a press release

Conselice and colleagues found that there were significantly more galaxies at earlier times.

Read more at Discovery News

Jumping Spiders Hear You from Across the Room

At this moment you are probably in a room with a spider that can hear everything from your phone ringing to your conversations, according to new research on spiders that don't even have proper ears.

This discovery, detailed in Current Biology, was triggered by a completely unplanned event: a researcher's chair squeaked.

Paul Shamble was in a lab at Cornell University with colleague Gil Menda and others making neural recordings from the brains of jumping spiders. Shamble, who has since moved to Harvard, and the others were exploring how jumping spiders process visual information. While setting up an experiment, Menda's chair squeaked across the floor.

It was then that a speaker, set up to record the sounds of spider brain neurons firing, started to blast out multiple "pops." Whenever the chair squeaked, the popping followed.

"That was a really exciting moment for all of us in the lab," Shamble said.

Jumping spider.
He added that when he and his team did behavioral experiments later, "the response was really clear -- the jumping spiders would be wandering along and just stop instantly when the sound came on."

In short, if you have a squeaky chair in your room, you're probably driving the resident jumping spiders nuts. And the sounds aren't limited to squeaks, either.

"Jumping spider hearing is almost certainly sensitive enough to hear you talking," Shamble said, but added that such spiders are "really only sensitive to low frequency tones, so lots of human speech is too high for them to hear."

It's likely, he says, that spiders tune into lower frequency sounds as a sort of warning system. In the same way a shout might catch your attention and make you stop what you're doing, a low noise puts the spiders on alert.

Female Phidippus audax.
Spiders hear noises using sensory hairs, but it was thought that these hairs could only pick up very close sounds. This finding shows that jumping spiders actually have an acute sense of hearing.

"Their sensory hairs are basically everywhere, but especially on their legs and their head -- and there are lots of them, not just one or two," Shamble said. "That said, these are the only things they have for hearing sound; spiders don't seem to have proper ears at all."

As for why jumping spiders evolved such great hearing, the researchers suspect that they use the sense to listen for predators, such as parasitoid wasps. The ability could have a role in attracting and impressing mates. The spiders may also be listening for prey.

Since, as their name suggests, the spiders like to jump, they are known to pounce on people. Some are even black and red in color, causing some to think they are being attacked by a black widow, but Shamble said that these spiders hardly consider us to be prey.

Read more at Discovery News

Thirsty Concrete Reduces Runoff at Yellowstone Park

The iconic Old Faithful geyser at Yellowstone National Park spouts an impressive 3,700 to 8,400 gallons of water every hour. Perhaps more striking is the geothermal network below it, which supports nearly two-thirds of the entire Earth's geysers.

To preserve that network for as long as possible, the park is replacing thousands of square feet of crumbling, petroleum-based asphalt sidewalks with a semi-porous material called Flexi-Pave. Conventional sidewalks promote rivers of runoff that not only wash away soil and cause erosion, but also leach toxins into the ground.

Flexi-Pave is different. It absorbs 3,000 gallons of water per hour, which reduces runoff and returns the rainwater to the ground in a natural pattern, where it can replenish the geyser basin below.

Wait, it gets better. The material is made from a mix of used tires as well as bits of stone. The aggregate is held together with a polymer binder invented by Flexi-Pave manufacturer KBI, a partner along with Michelin on the project. And because the material becomes inert after its manufactured, no toxins leach into the soil as the rainwater flows through it.

KBI just paved a 4,160-square-foot path near Old Faithful, the second phase of the Old Faithful Walkway Project. For this section, they ground up more than 1,500 used Michelin tires. Back in Sept. 2015, KBI repurposed 900 end-of-life tires.

"Helping to create a next-generation trail system in Yellowstone National Park is very gratifying," Kevin Bagnall, CEO and founder of KBI said in a press statement. "Flexi-Pave not only provides an environmentally friendly solution for the Old Faithful area, it prevents thousands of old tires from ending up in a landfill or being burned for fuel."

Watch the video to see KBI's crew laying down the Flexi-Pave in America's oldest national park.

From Discovery News

Moon Craters Appearing Faster Than Thought

New craters are forming on the surface of the moon more frequently than scientists had predicted, a new study has found. The discovery raises concerns about future moon missions, which may face an increased risk of being hit by falling space rocks.

The moon is dotted with a vast number of craters, some billions of years old. Because the moon has no atmosphere, falling space rocks don't burn up like they do on Earth, which leaves the moon's surface vulnerable to a constant stream of cosmic impacts that gradually churn the top layer of material on its surface. You can see a before-and-after video of a new moon crater here.

Previous studies of lunar craters shed light on how they formed and on the past rate of cratering, which in turn yielded insights on the age of various features of the moon's surface. However, less was known about the contemporary rate of lunar crater formation, which could give insight on the risk of bombardment that any missions to the moon might face.

To find out more about the present lunar crater formation rate, a group of scientists analyzed more than 14,000 pairs of before-and-after images of the moon's surface, taken by NASA's Lunar Reconnaissance Orbiter (LRO). These images covered 6.6 percent of the lunar surface — about 960,000 square miles (2.49 million square kilometers) — and could reveal when a spot was crater-free and when it later had a crater. The time gaps between observations spanned between 176 and 1,241 Earth days.

A 39-foot (12 meter) diameter impact crater formed between Oct. 25, 2012, and April 21, 2013, and was discovered in a before-and-after image created from two Narrow Angle Camera (NAC) images. The image covers an area 1,200 m wide.
"When looking at just a single image, many of the newly formed features are indistinguishable from their surroundings," said study lead author Emerson Speyerer, a planetary scientist at the Arizona State University at Tempe. "It's only with these detailed comparisons with previous images that we can separate out these small surface changes.

The researchers discovered 222 craters on the moon that appeared on the surface after the first LRO images were taken — that is 33 percent more than predicted by current models. These were at least 32 feet (10 meters) across, and ranged up to about 140 feet (43 m) wide.

The top image shows a low-reflectance splotch, while the bottom image shows a high-reflectance splotch that was created by a small impactor or secondary ejecta from a larger impact. In either case, the top few centimeters of the regolith (soil) was churned.
The scientists also found broad zones around these new craters that they interpreted as the remains of jets of debris following impacts. They estimated this secondary cratering process is churning the top 0.8 inches (2 centimeters) of lunar dirt, or regolith, across the entire lunar surface more than 100 times faster than thought.

"I'm excited by the fact that we can see the regolith evolve and churn — a process that was believed to take hundreds of thousands to millions of years to occur — in images acquired over the past several years," Speyerer told Space.com.

These new findings also suggest that a number of young features on the moon's surface, such as recent volcanic deposits, "may in fact be even a bit younger than previously thought," Speyerer said.

Read more at Discovery News

Chimp Mothers Teach Offspring to Use Tools

For the first time, according to researchers, adult chimp mothers in the wild have been documented teaching tool use to their offspring.

Anthropologists from Washington University in St. Louis shot video footage of the activity during field work in the Goualougo Triangle of the Republic of Congo. The recording captured mother chimpanzees handing off termite-fishing poles to their young. The hand-offs met the criteria for what the scientists call "tool transfer."

"Tool transfers are costly for mothers, whose ability to forage for termites is reduced, but are beneficial for offspring, who gain increased opportunity to learn tool skills and gather termites," said Stephanie Musgrave, the study's lead author, in a statement. "This is the first such evidence satisfying these criteria for teaching in wild apes."

It's been well documented that chimps fashion tools but, said Musgrave, "little evidence to date that adult chimpanzees teach youngsters tool skills."

The termite probes were chosen from select herb stems by the chimps and intentionally modified to have brush-tipped ends. "By sharing tools," explained Musgrave, "mothers may teach their offspring the appropriate material and form for manufacturing fishing probes."

In this video shot by the researchers, an adult female chimp at a termite nest hands a fishing probe to her offspring, who uses it to successfully fish for termites:

The researchers say their work can help inform our understanding of how skills are passed on.

"It is easy for us to take for granted the importance of sharing information to learn complex skills, as it is ubiquitous in humans," said study co-author Crickette Sanz. "Our research shows that the evolutionary origins of this behavior are likely rooted in contexts where particular skills are too challenging for an individual to invent on their own."

Read more at Discovery News

Oct 12, 2016

Prehistoric Voice Box Reveals Dinosaur-Era Sounds

Sixty-eight million years ago when dinosaurs roamed the Earth and Antarctica was warm and pleasant, a bird that looked like a cross between a duck and a goose filled the Antarctic skies with a deafening, honking call. Scientists know this through analysis of the oldest fossilized syrinx — a bird's equivalent of a voice box.

The organ, nicknamed the "squawk box," was a syrinx of Vegavis iaai, a Cretaceous-age bird found on Antarctica's Vega Island 66-69 million years ago. The discovery, outlined in the journal Nature, offers key, tangible evidence not only for what some prehistoric birds sounded like, but also birds' oversized relatives — dinosaurs.

Since birds evolved from dinosaurs, they may have developed the syrinx later — and dinosaurs likely never developed it. This means dinosaurs might not have been able to make noises similar to bird calls. In fact, it's also likely dinosaurs did not roar.

A reconstruction of Vega Island, Antarctica, shows Vegavis iaai flying overhead (sound-producing syrinx visible) and a medium-sized meat-eating dinosaur below that's producing noise with a closed mouth.
"Roaring is biologically implausible for dinosaurs," said Julia Clarke, a paleontologist at The University of Texas at Austin Jackson School of Geosciences, who discovered the squawk box. "We need to kill the dinosaur roar."

Clarke and her colleagues propose that most dinosaurs may have lacked a syrinx.

"This does not mean that they were silent," she said. "Crocodiles produce load low frequency sounds with a closed mouth. Most dinosaurs could have used the crocodile approach with a larynx (voice box) and made these kinds of sounds."

To determine what sounds V. iaai made, Clarke and her team used a high resolution X-ray imaging technique called microcomputed tomography to construct a three-dimensional computerized model of the syrinx. They also looked at how 12 groups of present-day birds vocalize, noting the related "hardware" of these birds that is made up bones and soft tissues. The researchers then compared that data on modern birds with their V. iaai squawk box model.

A detailed look at the newly found syrinx, aka squawk box
"Evidence from both other skeletal material as well as the syrinx indicates Vegavis iaai is closely related to living ducks and geese," Clarke said. "The shape of the asymmetrical syrinx (left vs right sides) is most similar to living female ducks. In males the syrinx is even more asymmetrical — with a giant protrusion on one side. Both male and female ducks create loud honks with an open mouth."

This means the dinosaur-era bird likely honked like a duck or a goose.

Intriguingly, the squawk box of this bird was more complex than that of even some birds today. Since these birds evolved from relatives that lived before V. iaai, an even simpler sound-producing organ must have emerged before V. iaii's lifetime. When that precisely happened, for now, remains a mystery.

The discovery, however, does suggest that "the sound landscape would be much more diverse" for birds during the dino age than that for dinosaurs, which weren't birds. (All birds are now considered to be dinosaurs, though.) Clarke added that the sounds would have included, not just honks, but also higher pitched calls and rooster-like crows. Neither the prehistoric birds nor the dinosaurs could roar, based on the fossil evidence.

Read more at Discovery News

The Northern Lights Make Strange Sounds: Here's Why

For more than 15 years, a lone scientist in southern Finland has spent countless winter nights among the snowy fields and frozen lakes around his village, in pursuit of one of the most ephemeral mysteries of the heavens: the faint, almost phantasmagorical sounds heard during intense displays of the aurora borealis, or northern lights.

The epic study by acoustician Unto K. Laine includes the first audio recordings of the muffled crackling or popping sometimes heard overhead during spectacular aurora displays.

Over the years, the sounds of the northern lights have been explained as illusions, imagination, inebriation or even voices from the spiritual world.

But Laine has shown the sounds are real, and he thinks he has found what causes them: sparks of electricity discharging beneath the aurora in an inversion layer of the atmosphere that can form in clear and calm weather conditions.

Laine told Live Science that he became interested in the phenomenon of so-called auroral acoustics about 25 years ago, when he and his friends heard sounds from an aurora after a nighttime music gathering in Finnish Lapland, in the far north of the country.

"This experience never left me. We had to concentrate — we did not move or talk at all," he said. "A few of us did not hear it, because at that time, the aurora wasn't very strong, and it was a very low-intensity sound. I could never forget this experience; it was so strange."

In 2000, Laine started to keep a careful watch on space weather forecasts for reports of intense solar flares that could supercharge auroras over the following nights. Auroras are caused by charged particles from solar flares interacting with the Earth's magnetic field and raining into the upper atmosphere, where they excite the nitrogen and oxygen atoms of the air to create the dramatic and colorful light shows.

"During all these years, I have checked the space weather two to three times a day, so not to miss any aurora events — and always, when the weather conditions are good, I go," he said.

Sounds out of space


Laine's solitary hunt for the elusive sound of the northern lights demanded great patience. There have been few intense auroras over Finland in the past 16 years, thanks in part to the "solar minimum," a period of decreased activity in the sun's natural 11-year solar cycle. Between 2004 and 2007, the sun experienced a lull in activity, according to NASA, which meant fewer solar flares and fewer auroras. In 2011, as solar activity ramped up, Laine started using a VLF loop antenna to measure magnetic fields and a microphone array to triangulate the locations of crackles and pops in the ever-changing sounds from the aurora.

"The sounds are diverse and can vary quite a lot, and it is very possible that there are many different mechanisms creating the sounds," he said. "I have been concentrating more on the clapping, popping and crackling, because they are good for estimating the direction of the sound."

In September 2011, during an intense aurora overhead, Laine's microphone array was able to triangulate the locations of several distinct "clap" sounds from the celestial display. To his surprise, the results showed the sounds were originating just 230 feet (70 meters) above the ground — much lower than the auroras themselves, which occur at altitudes of up to 300 kilometers (185 miles).

Laine's unexpected discovery partly explained one of the mysteries of the acoustics of auroras: How can faint sounds from auroras so high in the atmosphere be heard at the surface of the Earth?

In a research paper published in 2012, which included the first recordings of auroral sounds ever made, Laine also ruled out a theory that the sounds could be made by trees, because his microphones had been set in open fields and beside frozen lakes.

The acoustics of auroras


Now, Laine thinks he may have discovered a mechanism in the atmosphere that explains at least some of the sounds caused by auroras.

During an intense display of the northern lights over southern Finland on March 17 and 18, 2013, when the temperature in the village of Fiskars was minus 4 degrees Fahrenheit (minus 20 degrees Celsius), Laine recorded hundreds of auroral sound events.

He also measured magnetic pulses that occurred immediately before each sound event, which corresponded in strength to the volume of the sounds.

Then, Laine matched his measurements to data from the Finnish Meteorological Institute for the same night, and found they had measured a thermal inversion layer in the atmosphere — a blanket of relatively warm air that traps cold air next to the ground in calm conditions — at the same altitude where the noises originated.

Read more at Discovery News

Tiny 'Beardogs' Get New Place in Carnivore Family Tree

A group of Chihuahua-size "beardogs" have new names a mere 37 million years after they went extinct.

Beardogs, or amphicynids, were carnivores that ranged in size from just a few pounds to well over 1,000 lbs. (450 kilograms). Texas was home to some of the earliest members of this group, including two species of tiny beardog that have been reclassified with new scientific names.

"We've known about these curious little critters for 30 years, but couldn't tell exactly what kind of carnivores they were," study researcher Susumu Tomiya, a postdoctoral scholar at the Field Museum in Chicago, said in a statement. Tomiya and his colleagues reported their findings today (Oct. 11) in the journal Royal Society Open Science.

Tomiya had just started working at the Field Museum when he noticed that a couple of small carnivore jaws in the mammal collection seemed wrongly categorized. Both were small beardogs that lived about 37 million or 38 million years ago in what is now Texas.

"The genus the specimen had been assigned to didn't seem to fit some of the features on the teeth," Tomiya said.

The two jaw specimens were called Miacis australis and Miacis cognitus, and both had flat surfaces along the upper teeth that would have been used for crushing, rather than just ripping or tearing. These features made Tomiya think that the animals weren't pure carnivores, but also ate things like berries and insects. The teeth also looked similar to those seen in later, larger beardogs, Tomiya thought.

He and his colleagues used high-resolution X-ray computed tomography (CT) scanning to digitally reconstruct the jaws and skull fragments of the two animals. The high-definition digital reconstructions allowed them to compare internal anatomical features, like the cavity where the inner ear would have been,with the anatomy of other beardogs.

As a result, the researchers renamed the two beardogs. Miacis cognitus became Gustafsonia cognita, and Miacis australis became Angelacrtocyon australis.

The name change matters because it helps clarify the early evolutionary history of beardogs. These animals are part of the same group as dogs, wolves, bears, foxes, sea lions and weasels.

"They're equally related to all of the dog relatives alive today," Tomiya said. "They're not the direct ancestors of modern wolves and bears, but more like their cousins."

Read more at Discovery News

Where Blasphemy Carries a Death Sentence

On Thursday, October 13, Pakistani Christian Asia Bibi will face her final appeal in what has been a six-year-long ordeal on the charge of blasphemy. Following an altercation with a Muslim women over water, Bibi insulted the prophet Muhammad, an infraction for which Bibi was convicted in 2010 and sentenced to death by hanging.

If Bibi's sentence is not overturned, she will be the first woman to be executed since blasphemy laws were enacted in Pakistan in the 1980s.

When first created in 1980, the law originally called for a maximum sentence of three years in jail. In 1982, a separate clause was passed calling for life imprisonment for willful desecration of the Quran. In 1986, yet another clause was added recommending the death penalty or life imprisonment for blasphemy against Muhammad, according to the BBC.

Since the 1980s, more than 1,300 have been accused of blasphemy. Scores have been killed as a result, some even before their trials began as a result of vigilante violence. And Pakistan isn't alone in putting people to death for blasphemy.

According to the latest International Humanist and Ethical Union's Freedom of Thought report, 13 countries currently have laws on the books carrying a penalty of death for blasphemy or apostasy. Including Pakistan, the other 13 countries are Afghanistan, Iran, Malaysia, Maldives, Mauritania, Nigeria, Qatar, Saudi Arabia, Somalia, Sudan, United Arab Emirates and Yemen. Each of these countries have adopted Islamic law as the ideological foundation of the government.

Because blasphemy law is so subjective, the cases brought up in the various countries that try and execute for insulting religious belief have ranged from egregious to ridiculous.

In 2007, in Sudan, British schoolteacher Gillian Gibbons was arrested and interrogated for allegedly insulting Islam after allowing her class of six-year-olds to name a teddy bear "Muhammad." Thousands of protestors took to the streets, calling for Gibbons' execution. It took the intervention of the British government and a presidential pardon from the government of Sudan to get Gibbons out of jail.

In Saudi Arabia, which also puts people to death for "sorcery," usually by beheading, religious authorities issued a fatwa against Pokemon Go, decrying it as blasphemous. "It is shocking that the word 'evolution' has been much on the tongues of children," the fatwa read, according to a Reuters report.

In Iran, an Islamic theocracy, political advocacy can come off as blasphemy, as was the case for Hashem Aghajari, a history professor and disabled war veteran, in 2002 calling for religious reform. His speech garnered massive protests, and Aghajari was tried, convicted and sentenced to death, though following appeals his punishment was reduced to jail time.

Blasphemy laws restrict religious freedom and promote intolerance of minority religions, and for that reason, a United Nations special investigator on religious freedom called for their universal repeal. Although they may not carry a death sentence everywhere, blasphemy laws on the books in about a quarter (26 percent) of the world's countries and territories, according to Pew Research Center.

From Discovery News

A Chunk of India and Eurasia Just Disappeared

Half of the mass of Eurasia and India is missing, new research finds, and may have been swallowed up by the Earth's mantle.

If so, that would be a surprise, as geoscientists thought that continental crust — the kind that makes up major landmasses — was too buoyant to dive down into the mantle, the pliable middle layer of the planet upon which the crust rides.

"It used to be thought that the mantle and the crust interacted only in a relatively minor way," study researcher David Rowley, a geoscientist at the University of Chicago, said in a statement. "This work suggests that, at least in certain circumstances, that's not true."

The mystery of the missing crust emerged as Rowley and his colleagues examined the slow-moving collision of the Indian and Eurasian tectonic plates. These two rafts of continental crust have been bumping against each other for 60 million years, crumpling up to form the Himalayan mountains. The researchers combined multiple data sources to figure out the original size of the two continental plates before they started colliding.

These new calculations, published online Sept. 19 in the journal Nature Geoscience, revealed a strange imbalance. Even after accounting for the ruched bits of crust that climbed upward to form the Himalayas, the excess that squeezed out the sides to form southeast Asia, and the crust that eroded over 60 million years and ended up in the oceans, Rowley and his colleagues couldn't explain where half of the original mass of India and Eurasia went.

That led to an unprecedented conclusion.

"If we've accounted for all possible solutions at the surface, it means the remaining mass must have been recycled wholesale into the mantle," said study researcher Miquela Ingalls, a graduate student in geophysical sciences at the University of Chicago.

Unknown interactions

Continental crust isn't supposed to be able to sink in that way. Geoscientists have long known that dense oceanic crust can be "recycled" into the mantle — this is the geologic process that happens at subduction zones like the one off the coast of California. Oceanic crust slides under less dense continental crust like a conveyer belt and, under pressure, becomes ductile and gooey, mixing in with the mantle.

But because continental crust is so buoyant, researchers thought it acted more like a pool raft: Push it down, and it will just pop back up again.

Read more at Discovery News

Oct 11, 2016

Face of Bronze Age Warrior Revealed

The face of a warrior buried in a treasure-packed grave in Greece some 3,500 years ago has now been revealed — and he was a looker.

Dubbed the "Griffin Warrior," from an ivory plaque depicting the mythical beast within his burial, the man featured a broad, handsome face with a square jaw and powerful neck.

Reconstructing the closest possible depiction of the Griffin Warrior was not an easy task, says Tobias Houlton, a specialist in facial reconstruction, who worked on the project with his colleague Lynne Schepartz of the University of the Witwatersrand in Johannesburg, South Africa.

The skull of the man, thought to have been between 30 and 35 when he died around 1500 BC, was in very poor condition.

"It was multi-fragmented, with evident deterioration of the bones across the mid-face, affecting the nasal region and inner eye details," Houlton told Discovery News. "Prior to re-assembly, we were uncertain that a facial reconstruction would be possible," he added.

To reach the best approximation of the warrior's face, Houlton used the so-called Manchester method. The facial tissues are laid from the skull surface outward by using depth marker pegs to determine thickness. The shape, size and position of the eyes, ears, nose and mouth are determined through the features of the underlying skull.

The condition of the skull did not allow Houlton to reconstruct the regions around the eyes and nose.

To compensate, Houlton and Schepartz generated an average face template using a face pool of 50 modern Greek males aged 25-35 years.

"This is the closest possible population group data we can access in relation to the Griffin Warrior. The nose from the template was then used to facilitate the nasal reconstruction and identify the most likely angle of the eyes," Houlton said.

He noted that features such as skin and hair color, which would require DNA information, could only be assumed according to identified trends in Mycenaean and Minoan artifacts.

"We used many types of comparative information, including Mycenaean wall paintings for the hairstyle," Schepartz told Discovery News.

The result is a sturdy man with long black hair, staring from a past that is reminiscent of Homer's epics.

The Griffin Warrior's tomb, measuring about 5 feet deep, 4 feet wide and 8 feet long, was found near the remains of the fabled Palace of Nestor, who headed a contingent of Greek forces at Troy in Homer's Iliad.

"This is not the grave of the legendary King Nestor, nor is it the grave of his father, Neleus. The warrior predates the time of Nestor and Neleus by, perhaps, 200 or 300 years," Stocker said.

Analysis of beautifully engraved rings found in the tomb revealed the warrior was part of the elite that ruled Pylos right around the time the Mycenaeans were conquering the Minoans, adopting much of their culture.

It is not yet known if the man was a Minoan warrior or a native Mycenaean steeped in Minoan culture.

The lavish contents of the man's grave had hinted at his importance. It was found in the summer of 2015 by Jack Davis and Sharon Stocker, a husband-and-wife team from the University of Cincinnati, as they excavated what they believed was an ancient house in Pylos, a city on the southwest coast of Greece.

What they found turned out to be a treasure-packed grave and one of the most remarkable archaeological discoveries since the Second World War.

Stretched out on his back, a skeleton lay on the floor of the grave, undisturbed for 3,500 years. A dazzling hoard of more than 2,000 objects surrounded the remains. A bronze sword, with an ivory handle, laced with gold, was placed near the head and chest. Next to it was a gold-handled dagger, while more weapons were scattered around the legs and feet.

A plaque of carved ivory with a depiction of a griffon with huge wings lay between the man's legs and nearby was a bronze mirror with an ivory handle.

Read more at Discovery News

Obama: NASA Will Land on Mars in the 2030s

In a patriotic and emotional op-ed for CNN Tuesday morning, President Barack Obama reaffirmed NASA's aim to land and return astronauts on the Martian surface by the 2030s, "with the ultimate ambition to one day remain there for an extended time."

To take this next giant leap into interplanetary space, Obama added, NASA will partner with private companies to make this vision a possibility.

"Getting to Mars will require continued cooperation between government and private innovators, and we're already well on our way," he writes. "Within the next two years, private companies will for the first time send astronauts to the International Space Station."

Since NASA's inception, the space agency has contracted private companies to provide hardware for space exploration and NASA currently contracts private space launch companies to deliver equipment and supplies to the International Space Station (ISS), invigorating a new race to commercialize space.

Now the space station is, in part, supplied by SpaceX and Orbital Sciences and these partnerships are set to continue and expand to the delivery of astronauts to the orbiting outpost. So it may not come as a surprise that NASA will seek partnerships in the private sector to make a Mars mission possible.

Six years ago, on Oct. 11, 2010, Obama signed into law a redirection in NASA's road map to Mars, skipping the moon and developing the technologies to visit an asteroid and then send a human mission to the Red Planet. And in his op-ed, Obama reflects on the achievements NASA has made in the past six years to drive forward investment in the private sector, while boosting the economy and inspiring the nation. But now, NASA aims to push humanity beyond Earth orbit.

"I'm excited to announce that we are working with our commercial partners to build new habitats that can sustain and transport astronauts on long-duration missions in deep space," he writes. "These missions will teach us how humans can live far from Earth -- something we'll need for the long journey to Mars."

In response to the President's remarks, NASA Administrator Charles Bolden said that NASA is primed to test technologies that will allow astronauts to live in space for days or weeks away from Earth, rather than hours.

"For example, in the mid-2020s, NASA's Asteroid Redirect Mission will send a robotic spacecraft to a nearby asteroid to test out important exploration technologies such as solar-electric propulsion, conduct scientific and planetary defense experiments, and then return a boulder from the asteroid to an orbit around the Moon for astronauts to study," Bolden writes. The Asteroid Redirect Mission -- known as "ARM" -- will be an opportunity to prepare and refine technologies for missions to Mars and beyond.

In his statement, Bolden provided some detail on what NASA is doing now to make these aims possible, including the "NextSTEP" program that is asking private enterprises to come up with new and innovative designs for space habitats.

In addition, Bolden discussed the possibility of adding a "commercial module" to a special port on the space station in "preparation for one or more future commercial stations in Low Earth Orbit, ready to take over for the Space Station once its mission ends in the 2020s." In response to this challenge, private companies have responded "enthusiastically," he writes.

NASA continues to develop its next powerful rocket, the Space Launch System (SLS) and Orion capsule that will be used to get astronauts to asteroids and Mars, but in the background, private companies are developing their own, independent plans for getting to Mars.

Read more at Discovery News

Goliath Worms 'Drown' and Then Recover

Manduca sexta caterpillar, also known as a "goliath worm", found in Urbana, Illinois, U.S.
Hefty, bright-green caterpillars sometimes called goliath worms are living up to their moniker: They are so tough, they can survive underwater for hours, scientists have found.

And during their pupa stage — encased in a chrysalis before transforming into adult moths — they can survive for days at a time without surfacing.

Researchers discovered that the hardy caterpillars ofManduca sexta moths could recover after spending as much as 4 hours immersed in water. The pupae were even more resilient, emerging after a five-day soak and showing no long-term ill effects.

Caterpillars are the larvae of moths and butterflies, and many species are known to have extraordinary adaptations during this life stage that help them weather tough conditions or escape threats. Some click, squeak or whistle to scare off attackers, while others rely on defensive barfing. Someuse their poop to send chemical signals that trick plants into lowering their defenses, while others pretend to be poop, to fool predators.

M. sexta larvae, which pupate (grow into an adult) in the ground, face a particularly tough challenge due to seasonal flooding in their desert habitat; how they might overcome that challenge was a question that intrigued study co-author H. Arthur Woods, an entomologist at the University of Montana.

"I've always been really impressed with the torrential rains and flooding that can occur during the summer monsoon rains," Woods told Live Science. "We often saw Manduca habitat that got flooded out for days at a time, and we started to wonder whether and how pupae could survive that water."

Insects experiencing long dunks underwater use one of two mechanisms to survive and recover, Woods said.

One technique involves the insect extracting oxygen from the surrounding water; that requires specialized body parts. Mayflies and damselflies, for example, have a type of gill that connects to the trachea and conveys dissolved oxygen in water into the insect's body, allowing them to breathe even when fully immersed.

The other method involves sealing up the body and getting by without oxygen, a process known as anaerobic metabolism. But this can be risky, Woods said. This type of metabolism produces toxic byproducts, which, at high levels, can poison the insect.

"So usually insects can use anaerobic metabolism for finite periods of time," he said.

To find out M. sexta's strategy for surviving underwater, the researchers immersed caterpillars and the more developed pupae. The caterpillars were able to recover after 4 hours underwater — not too shabby. But pupae were "the champs" at recovery, according to Woods. He and his colleagues found that the submerged pupae didn't draw upon dissolved oxygen, and relied on anaerobic metabolism to keep going when they were underwater, for as long as five days.

What surprised Woods was how long they could do it, and still recover.

In the absence of oxygen, a compound called lactate built up in the M. sexta pupae's cells. This could have had fatal consequences, but the scientists found that M. sexta was capable of quickly metabolizing, or breaking down, the lactate once they were removed from the water.

Read more at Discovery News

Mice Sing Love Songs Like a Jet Engine

Ultra-high pitched mouse squeaks have something in common with the roar of a jet engine. New research finds that the rodents make ultrasound bleeps by creating a small air jet in their windpipes, employing a mechanism previously seen only in jet engines and high-speed subsonic flows.

The ultrasonic whistles are important because rodents use them to sing mating songs and make announcements about their territory. The sounds are too high in frequency to be detected by the human ear.

Until now, though, no one knew exactly how these whistles were produced. Researchers led by biologist Coen Elemans of the University of Southern Denmark used high-speed camera scopes to capture images of the larynxes, or voice boxes, of mice as the animals made their vocalizations. The cameras captured 100,000 frames per second for analysis.

Two competing hypotheses had been put forward to explain how the ultrasonic vocalizations are made. The first suggested that the sounds are the result of superficial vocal-cord vibrations; essentially, air moves through the vocal cords as it would for any typical vocalization. However, the videos showed that the vocal cords weren't vibrating, even superficially.

The second explanation was that mice make the noises by forcing air through two constricted holes in the larynx, much in the same way a tea kettle whistles when steam forces its way through the kettle's openings. To test this, the researchers surgically removed the upper thyroid tissue in the mouse larynx, trying to find the constrictions. The researchers found that removal of this tissue silenced the ultrasonic vocalizations. They then replaced the tissue with a metal plate and found that the mice could again vocalize, without any sort of second constriction. Thus, the tea kettle theory failed to hold up.

What actually happens, Elemans and his colleagues found, is that a small jet of air originates in the windpipe and flows against the inner wall of the larynx. The air waves bounce back from the wall, traveling upstream into the air jet and creating a feedback loop that creates the whistling sound.

"Interestingly, this mechanism is known only to produce sound in supersonic-flow applications, such as vertical takeoff and landing with jet engines, or high-speed subsonic flows, such as jets for rapid cooling of electrical components and turbines," study researcher Anurag Agarwal of the University of Cambridge said in a statement. "Mice seem to be doing something very complicated and clever to make ultrasound."

Read more at Discovery News

Oct 10, 2016

Was the secret spice in primal gene soup a thickener?

Gene puddle primeval, a drawing by talented first author Christine He to illustrate her discovery that viscosity moves spontaneous gene strand copying forward.
The original recipe for gene soup may have been simple -- rain, a jumble of common molecules, warm sunshine, and nighttime cooling. Then add a pinch of thickener.

The last ingredient may have helped gene-like strands to copy themselves in puddles for the first time ever, billions of years ago when Earth was devoid of life, researchers at the Georgia Institute of Technology have found. Their novel discoveries add to a growing body of evidence that suggests first life may have evolved with relative ease, here and possibly elsewhere in the universe.

And they offer a straightforward answer to a gnawing 50-year-old question: How did precursors to the present-day genetic code first duplicate themselves before the existence of enzymes that are indispensable to that process today?

The spice of life?

For generations, scientists pursuing an answer performed experiments in water but hit a wall.

Georgia Tech researchers Christine He and Isaac Gállego overcame it by adding an off-the-shelf viscous solvent (the thickener). In separate experiments with DNA then RNA, the copying process proceeded.

"I think it's very, very different from anything that's been done before," said researcher He. "We can change the physical environment in an easy way, and promote these processes that wouldn't happen in conditions ordinarily being used."

Easy recipe

Easy is crucial, said Martha Grover, a professor who oversaw the research at Georgia Tech's School of Chemical and Biomolecular Engineering. Easy reactions are likely to be more productive and more prevalent.

"A simple and robust process like this one could have operated in a variety of environments and concentrations making it more realistic in moving evolution forward," she said.

Grover's lab and that of Nick Hud at Georgia Tech's School of Chemistry and Biochemistry published the results on Monday, October 10, 2016 in the journal Nature Chemistry. Their research has been funded by the National Science Foundation and the NASA Astrobiology Program under the NASA/NSF Center for Chemical Evolution.

Nucleotide noodles

Earliest life was based on RNA, or a similar polymer, according to a hypothesis called the RNA World. In that scenario, on the evolutionary timeline, the self-replication of RNA strands long enough to be potential genes would roughly mark the doorstep to life.

Those long nucleotide chains may have been mixed together in puddles with shorter nucleotide chains. Heat from the sun would have made long strands detach from their helix structures, giving short ones a chance to match up with them, and become their copies.

But there's a problem.

In water alone, when cooling sets in, the long chains snap back into their helix structure so rapidly that there's no time for the matching process with the shorter chains. That snapping shut, which happens in both RNA and DNA, is called "strand inhibition," and in living cells, enzymes solve the problem of keeping the long chains apart while gene strands duplicate.

More like a stew

"The problem is a problem in water, which everybody sort of looks at in prebiotic (pre-life) chemistry," said graduate research assistant He. She felt it was time to rethink that, and her expertise in chemical engineering helped.

High viscosity has been known to slow down the movement of long strands of DNA, RNA and other polymers.

"It's a little like making them swim in honey," Grover said. Applying that to origin-of-life chemistry seemed obvious, because in prebiotic times, there probably were quite a few sticky puddles.

"In that solution, it gives the short nucleotides, which move faster, time to jump onto the long strand and piece together a duplicate of the long strand," researcher He said. In her experiments, it worked.

Hairpins in the soup

And it produced an encouraging surprise. The DNA and RNA strands folded onto themselves forming shapes called hairpins.

"In the beginning, we didn't realize the importance of the internal structure," Christine He said. Then they noticed that the shape was helping keep RNA and DNA available for the pairing process. "Hairpin formation is integral to keeping them open," Grover said.

But it also could have accelerated chemical evolution in another way. "The solution is selecting here for sequences that fold, and that would have more potential for functional activity -- like a ribozyme," said researcher He.

Ribozymes are enzymes made of RNA, and enzymes catalyze biochemical processes. To have them evolve in the same solution that promotes genetic code replication could have shortened the path to first life.

"You really need to amplify functional sequences for evolution to move forward," Grover said. The folds were an unexpected side-effect, and finding them paves the way for future research.

Next ingredient?

The Georgia Tech scientists used real gene strands in their experiments, which may sound mundane, but in the past, some researchers have specially engineered DNA and RNA sequences in attempts to arrive at similar results.

He and Gállego's use of a naturally occurring gene, rather than a specifically engineered sequence, shows that viscosity could have been a very general solution to promote copying of nucleic acids with mixed length and sequences.

To facilitate quick, clear outcomes, the Georgia Tech researchers used purified short nucleotide chains and applied them in ratios that favored productive reactions. But they had started out with messier, less pure ingredients, and the experience was worthwhile.

"Considering a pre-biotic soup, it's probably messy; it's got a lot of impurities," Christine He said. "When we first started out with more impure nucleotides, it still worked. Maybe the same reaction really could have happened in a messy puddle billions of years ago."

The viscous solvent was glycholine, a mixture of glycerol and choline chloride. It was not likely present on pre-biotic Earth, but other viscous solvents likely were.

Read more at Science Daily

Rare Venomous Sea Snake Pops Up in Iranian Waters

Shown is the smallish head of an adult Günther's sea snake.
Off the western coast of the Gulf of Oman, a fishing vessel turned up something curious in its by-catch: A rare, venomous sea snake that was 248 miles (400 kilometers) from where it was supposed to be.

Caught in the haul was a Günther's sea snake (Microcephalophis cantoris), a little-seen aquatic animal thought to inhabit only the waters from the western Malay peninsula to the coasts of Myanmar, India, Sri Lanka, and Pakistan.

The animal was found during a sea snake population survey being performed in the Persian Gulf and the Gulf of Oman by a team of Iranian and French scientists.

Almost all sea snakes (Hydrophiinae) live fully aquatic lives. They don't have gills, so, like whales, they have to surface for air. Their tails, shaped a bit like paddles, propel them through the water.

The Günther's sea snake was first discovered in 1864 by zoologist, Albert Günther. It can grow to nearly 5 feet (1,448 millimeters) long for males and almost 6 feet (1,829 millimeters) for females. It has a small head compared to the rest of its body and it's spotted so infrequently that the IUCN "red list" of threatened species designates it as "Data Deficient."

The scientists have included the Iran snake sighting in a new sea-snake checklist for the Gulf of Oman and Persian Gulf that has just been published in the journal ZooKeys.

There are 62 species of venomous sea snake globally, spread largely throughout Indo-Pacific waters (the yellow-bellied sea snake, an exception, can be found in all oceans except for the Atlantic). According to the researchers, the new sighting brings to just 10 the count of sea snake species spotted in the Persian Gulf and the Gulf of Oman. Here's one in action, a species called Hydrophis lapemoides:

From Discovery News

New Dead Sea Scrolls: The Real Thing?

The Psalms scroll, one of the established Dead Sea scrolls.
The Dead Sea Scrolls are about 2,000 years old and hold text from the Hebrew Bible. Hundreds of fragments of the scrolls were first found between 1947 and 1956 in caves in Qumran in the Judean Desert.

More recently, additional scroll fragments have come to light. Since 2002, around 70 Dead Sea Scrolls fragments have appeared on the antiquities market, said Eibert Tigchelaar, a professor at the University of Leuven in Belgium, in an interview with Live Science.

Tigchelaar believes that some of the scroll fragments that have recently appeared are actually modern-day forgeries, while others are not from Qumran, but rather other caves in the Judean Desert, possibly ones that haven't been discovered by archaeologists.

"I think what we have here is a mix of material that is authentic and of material that are forgeries," Tigchelaar told Live Science.

One of his arguments supporting the forgery claim is that of the 70 fragments that have appeared only one or two seem to be part of the 900 manuscripts found in the Qumran caves. To have so many scroll fragments that are not part of the other manuscripts found at Qumran is "statistically impossible," Tigchelaar said.

Additionally, Tigchelaar has found that most of the 70 new scroll fragments are from books of the Hebrew Bible, whereas the manuscripts found at Qumran contain a wider mix of texts, including calendars, community rules and apocryphal (noncanonical) texts.

Some of the new scroll fragments also contain oddities in their writing, such as small letters that appear to be crammed in at the edge of fragments (a fragment is supposed to be part of a manuscript that fell apart), Tigchelaar and other scholars have found.

Some of the scrolls may be authentic but not from Qumran, Tigchelaar said noting that the sellers could claim the scrolls were found in Qumran in order to boost the sales price or to avoid legal problems related to provenance.

After Israel took over the West Bank in 1967, laws were enacted that prohibited the selling of newly discovered scrolls. "If they [the new scroll fragments] were found after 1967, they [collectors and dealers] would not be allowed to own them or to sell them, but they would have to give them to the Israel Antiquities Authority," Tigchelaar said. He said that a close examination of the provenance of the new scroll fragments is needed.

More undiscovered scrolls are likely hidden in the Judean Desert, the Israel Antiquities Authority (IAA) said, adding that looters are probably already finding them. Last year, the antiquities authority launched a series of surveys and excavations in the Judean desert to try to find caves that may contain undiscovered scrolls.

"For years now our most important heritage and cultural assets have been excavated illicitly and plundered in the Judean Desert caves for reasons of greed," Miri Regev, Israel's Minister of Culture and Sports,said in a statement. "The goal of the national plan that we are advancing is to excavate and find all of the scrolls that remain in the caves, once and for all, so that they will be rescued and preserved by the state."

A team led by Randall Price, a professor at Liberty University in Virginia, and Oren Gutfeld, a researcher with the Hebrew University Institute of Archaeology in Jerusalem, will lead an excavation of one cave in the Judean Desert, which is set to begin in December.

That cave was partially excavated in the past, but "much remains to be excavated, including two wings of the cave at the back. There is always the possibility of finding scroll fragments because this cave, as well as others, shows signs of habitation from the time when the Qumran community who produced the scrolls was active," Price said.

Read more at Discovery News

Major Dust Storm Could Soon Hit Mars

This image illustrates the haze that engulfs Mars during major dust storms. These two images were taken in 2001, about a month apart.
A raging Martian dust storm is expected to sweep across the Red Planet within the next few months, according to a study that found a way to predict these otherwise variable weather events.

Global dust storms on Mars threaten robotic rovers traversing the Martian surface, as well as astronauts that may one day set up camp on the Red Planet. However, based on past weather patterns, Martian dust storms may soon become more predictable -- and if history repeats itself, the next storm is just around the corner, according to a statement from NASA.

"Mars will reach the midpoint of its current dust storm season on October 29th of this year," James Shirley, a planetary scientist at NASA's Jet Propulsion Laboratory, said in the statement. "Based on the historical pattern we found, we believe it is very likely that a global dust storm will begin within a few weeks or months of this date."

Local dust storms are fairly frequent on Mars. However, these localized storms can grow into regional or, in some cases, global storms. The dust storm season typically reaches its peak during the spring and summer in the planet's southern hemisphere, when Mars is closest to the sun, NASA officials said in the statement.

Dust storms on Mars create a massive haze that blankets the planet. The last global dust storm on Mars was in 2007. During this storm, NASA Mars rovers Spirit and Opportunity received scarce solar power, but were able to survive.

"The global dust storm in 2007 was the first major threat to the rovers since landing," John Callas, project manager for Spirit and Opportunity, said in the statement. "We had to take special measures to enable their survival for several weeks with little sunlight to keep them powered. Each rover powered up only a few minutes each day, enough to warm them up, then shut down to the next day without even communicating with Earth. For many days during the worst of the storm, the rovers were completely on their own."

Before 2007, major Martian dust storms have been recorded in 1971, 1977, 1982, 1994 and 2001. Using data on the orbital motion of Mars, Shirley discovered a pattern in the occurrence of these storms. He found other planets impact the momentum of Mars as it orbits the solar system's center of gravity.

The planet's momentum increases and decreases in a cycle that lasts 2.2 years, slightly longer than the Martian year, which is 1.9 years. Shirley found that global dust storms tend to occur when the momentum is increasing during the first part of the dust storm season, which doesn't happen during every Martian year. The finding is reported in a new study, published May 2015 in the journal Icarus.

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