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Friday, April 29, 2016

Dusty dinosaur bone sheds new light on perplexing giant predators


Written by Jason Thomson

A PhD student who stumbled across a forgotten dinosaur bone in a museum drawer has gleaned insight not only into the enigmatic Abelisaur, but also into a paleontological conundrum: Stromer's Riddle.

After discovering a discarded dinosaur bone in the dusty drawer of an Italian museum, researchers have published new insights into the predatory – yet surprisingly endearing – Abelisaur.

The study, published Monday in the journal Peer J, also wades into the murky waters of Stromer’s Riddle, formulated in the 1930s by German paleontologist Ernst Stromer, which asks how so many different top dinosaur predators could have coexisted.

The work also highlights one of the understated services provided by museums: sheltering a treasure trove of potential discoveries, just waiting for the right person to come along.

“I simply stumbled upon a drawer with some specimens,” says coauthor Alfio Chiarenza, a PhD student in paleontology at Imperial College London, in a telephone interview with The Christian Science Monitor. “This femur called my attention because I recognized dinosaur features – especially carnivorous dinosaur features.”

Mr. Chiarenza was at the Museum of Geology and Paleontology in Palermo, Italy, delivering an invited talk at a paleontology conference.

The museum curators were “enthusiastic collaborators, having heard my presentation that morning,” Chiarenza says, allowing him and his colleague Andrea Cau of the University of Bologna to investigate the bone in question.

“This find confirms that at that time, in Africa, there was something particularly favorable for the existence of giant predatory dinosaurs,” Mr. Cau tells the Monitor in an email interview. “There is nothing comparable in modern world.”

Femurs can be particularly helpful in determining a dinosaur's size, and even fragmentary bones can hold a rich tapestry of information, says Chiarenza.

Using this forgotten bone, the researchers calculated that this animal was one of the largest Abelisaurs ever found. Moreover, while paleontologists already knew that Abelisaurs had existed in North Africa, they had never before found evidence that they had grown so large in this region.

This particular bone originated from the Kem Kem Beds in Morocco, an area shrouded in the mysteries of Stromer’s Riddle, with bones of myriad giant predatory dinosaurs all heaped together, suggesting they roamed the region at the same time.

One theory attempts to erase the paradox by blaming geological processes for jumbling up the fossils, but Cau and Chiarenza offer a different take.

“We reviewed the literature on dinosaur assemblages in North Africa and drew the conclusion that they may well have been confined to different environments,” says Chiarenza. “So, Abelisaur probably lived further inland, while others lived in more coastal habitats, or alongside rivers and lakes.”

Recent research into the Spinosaur, for example, “the one with the big sail and the long snout,” as Chiarenza describes it, suggests it was somewhat aquatic or amphibious.

When asked what has most endeared them to Abelisaur, both researchers mentioned the minuscule forelimbs, far smaller even than T. rex’s puny appendages.

“Evidently, their arms were not a necessary organ for their mode of life, more or less as a long tail is not particularly important for the human lifestyle,” says Cau.

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Thursday, April 28, 2016

Oldest Nervous System Found in 520-Million-Year-Old Fossil


Written by Mindy Weisberger

A crustacean-like creature that lived during the Cambrian period left behind a central nerve cord that extended throughout the body, with visible clusters of tissue.

Fossils of an ancient creature resembling a shrimp with an armored head contain the oldest and best-preserved nervous system ever found, which could help scientists decipher the evolution of nervous systems in animals alive today, according to a new study.

The remarkable remains belonged to Chengjiangocaris kunmingensis, a crustaceanlike creature that lived 520 million years ago in what is now South China. The fossils revealed a long "ropelike" central nerve cord that extended throughout the body, with visible clusters of nerve tissue arranged along the cord, like beads strung on a thread. Even individual nerve structures could be detected, the scientists discovered.

They noted that the nerve tissue masses, or ganglia, grew progressively smaller along the central nerve cord, with the smallest masses being the ones most distant from C. kunmingensis's head. The researchers also found that the ganglia were associated with pairs of legs, which also reduced in size as they progressed along the animal's body.

Other structures in C. kunmingensis's nervous system—dozens of nerves that emerged at regular intervals from the nerve cord near the underside of the body—resembled those found in certain types of modern worms, but were absent in modern arthropods, offering clues to the scientists about how nervous systems adapted as different forms of life in these related lineages evolved.

ARTHROPOD ANCESTORS

C. kunmingensis lived during the Cambrian, the geologic period on Earth when life was rapidly diversifying, and they belonged to a group of arthropod ancestors called fuxianhuiids. These predecessors of insects, arachnids and crustaceans had armored heads and long, segmented bodies atop numerous pairs of legs—with three or four pairs per segment. These creatures likely scuttled across the sea bottom, scooping food into their mouths with a larger pair of limbs close to their heads, according to study co-author Javier Ortega-Hernández, a biologist in the Department of Zoology at the University of Cambridge, in the United Kingdom.

"Some of the largest individuals can reach up to 15 centimeters (6 inches) long, and they had at least 80 legs!" Ortega-Hernández told Live Science in an email.

But until now, little was known about what they looked like on the inside. Fossils typically provide scientists with records of bones, teeth, shells and other tough organic structures, while softer tissues generally disintegrate too quickly to be preserved, and are lost to time. But sometimes conditions prevail that protect the more delicate organs, allowing them to fossilize as well.

According to Ortega-Hernández, the Xiashiba area in Kunming, South China, where the specimens were found, is "world famous" for preserving soft-bodied life. He explained that the animals were likely buried in fine sediment in an oxygen-poor environment, which would protect the carcass from both scavengers and microbes, slowing or even halting decay.

"Eventually the carcasses become preserved in the fossil record, and the limited decay allows for the preservation of amazing morphological detail," he said.

"OUR JAWS DROPPED"

Prior studies from this period described fossils providing evidence of these arthropod ancestors' brains, but this study is the first to describe a complete nervous system from this ancient time, and with a level of detail that has never been seen before, the researchers said.

When the scientists looked closely at the ganglia masses, they spied fibers that measured around five-thousandths of a millimeter in length—"less than [the width of] a human hair," Ortega-Hernández said.

"Our jaws dropped when we put the specimens under the microscope and observed the fine nerves on the sides," he told Live Science. "It was hard to believe that something so small would be preserved along with the main nerve cord, but even more so because they show a unique organization that is otherwise unknown in living arthropods."

This organization—nerve cord, ganglia and dozens of nerves extending along each side—is similar to the neural systems of modern arthropods, Ortega-Hernández said. But, in arthropods alive today, the number of fine nerves is significantly lower, he added.

The number of these nerves is higher in velvet worms—cousins to arthropods—which suggests this feature dates back to the last shared ancestor for these two groups.

"It is possible that as arthropods became more specialized in their function, they managed to make their nervous system more efficient by reducing the number of nerves," Ortega-Hernández said, adding that this is only a hypothesis. "But it will be an interesting topic to explore in future studies," he said.

The findings were published online (Feb. 29) in the journal Proceedings of the National Academy of Sciences.

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Wednesday, April 27, 2016

Why You Move the Way You Do


Written by Simon Worrall

Animals—including humans—evolved to get from place to place.

“Everybody got to move somewhere,” sings Bob Dylan in "Mississippi." But why? Are we constantly in motion due to some fatal flaw in our make-up? A neurotic aversion to standing still? No, says Matt Wilkinson, author of Restless Creatures: The Story of Life in Ten Movements, the reason is bigger than that: Movement is what makes us human and has been the driving force of life on Earth.

Talking from his home in England, the Cambridge evolutionary biologist recalls what pterodactyls taught him about movement, how getting lost is important, and why our feet are, in his words, squidgy.

You say that locomotion has been the driving force of evolution. Explain why.

From the very beginning, right back to the very origin of life, those organisms with the ability to explore their environment had access to resources that others didn’t. Not only that, they were also able to move from place to place. Should any mishap befall them, they were more likely to survive. Locomotion has dominated the evolution of life and continues to do so. I ought to qualify that because plenty of creatures have become static and stay in on place. But you always find that somewhere in their life cycle, there is some motile phase. The benefits of being able to move are just too great.

Darwin is the inventor of the theory of evolution. He doesn’t say much about locomotion, though, does he?

Darwin’s approach was to put together a mechanism by which evolution might work from generation to generation. My approach is slightly different as I’m looking at a broader canvas. I’m not challenging the Darwinian idea, but rather embracing the idea of how important locomotion is. When you look at life as the history of locomotion, everything comes into focus.

As a child, you were fascinated by pterodactyls. Wind back the clock and explain how this childhood obsession got you interested in movement.

I guess all children are interested in dinosaurs but the extinct flying reptiles really captured my imagination. Here we have a group that is completely extinct but managed to do something very few groups have: develop full power of flight. It gave me a great opportunity to try and understand how these things worked. I became very interested in evolution in general, and in the rules of biomechanics: how living things work as machines, how they move, how they operate. It opened my eyes to how dominant this idea of locomotion is: how fully and thoroughly animals are shaped by the need to move effectively from place to place.

The received theory is that homo sapiens got his upright gait in the transition to a savannah environment, where it paid to stand tall. We got it wrong, though, didn’t we?

[Laughs] I think so. Though the idea isn’t mine alone. I agree with experts in this field, who suggest that the real transition to being an upright biped happened in the trees. The savannah stage was when we refined it. We never really became specialized in suspending from branches overhead like the apes. It meant our anatomy, our bodies, were still capable of becoming terrestrial bipeds.

To adapt the Nancy Sinatra song, these bones are made for walking, aren’t they? Talk about the everyday miracle of feet.

[Laughs] We take it so much for granted, but our feet are absolutely amazing marvels of bioengineering because they have to adopt different functions throughout every step. When we put one foot down, the foot needs to be quite squidgy, because it needs to provide a nice, stable base for the weight of the arches overhead and also to mold to the ground. When we lift the foot up, we want it to change into a more rigid lever, to give us a nice, efficient push-off. We have this nifty mechanism called the windlass mechanism, after the windlass crank-like system. As the toes get bent back on the ground, the heel gets pulled forward, twisted a little, and then that locks the foot into a rigid configuration. It’s a fantastically Gothic structure that enables us to walk efficiently. By contrast, the apes have emphasized the moldability of the foot much more than we have because they use the foot to grasp in a way that we don’t anymore.

One of the key fossils found in East Africa was that of a 4.4 million-year old-female. What did Ardi tell us about our early history?

Ardipithecus was about 4.5 million years old, putting her close to the divergence point of chimps and humans 6-7 million years ago. The prevailing opinion had been that our last common ancestors were chimp-like and walked on their knuckles. But Ardi didn’t have any knuckle-walking adaptations, especially in the wrist. Ardi also seemed able to walk bipedally much better than a chimp. This threw a spanner in the works as far as the theory of human locomotion was concerned.

Of course, if we didn’t have some kind of guidance system we would just crash about bumping into things. Talk about the GPS system we all have in our brains.

It has been argued that the brain is for locomotion, first and foremost. All the other stuff —the thinking, emotions, and consciousness—is essentially a bonus: a more refined way of gathering inputs and then generating an appropriate output, which in many cases, is just knowing which way to go.

It all goes back to the earlier stages of the animal kingdom. Once we start to get to jellyfish and sea anemones, we begin to see the use of the nervous system to steer the animal around. Sea squirts also give us a very useful illustration of the vertebrates’ closest invertebrate relatives. As larvae, they swim around and have something clearly related to the precursor of our vertebral column and central nervous system. But when they turn into adults and stop moving around, the central nervous system becomes a useless extravagance, so they just digest it.

You hint at an interesting connection between our love of storytelling and the way our brains have been designed for locomotion. Unpack that idea for us.

This is me speculating, but it refers to how our psychology has been adapted for locomotion. Just as our bodies have been clearly adapted for locomotion, so, too, have our minds. One aspect of this is the ability to draw navigational meaning from a sequence of vistas or images. It means we are then able to reconstruct a path from the landmarks that we encounter as we go along. It’s a very useful skill to be able to have because humans were traditionally hunter-gatherer societies so our navigational abilities are extraordinarily good.

Story telling is the same thing. What we’re doing there is taking a series of events that when knitted together into one narrative arc enables us to extract meaning from it. Our ability to draw meaning out of stories could well be using some of the same logical skills we use to draw navigational meaning out of a sequence of images.

You stress the importance to human civilization of what you call “wayfaring.” Explain what you mean.

Wayfaring is exploring locomotion. It’s not just moving as a means of getting from A to B. It’s trying to find out more about your environment through movement. Not just the environment but also about yourself and the world around you. Ultimately, it means getting lost—not needing to know exactly where you are going. Anything that causes you to employ your senses in a more thorough way as you’re moving from place to place is what I mean by wayfaring.

A good example of this is the Batek people of Malaysia, who have been studied quite extensively by Lye Tuck-Po. She found that the exploration of their forest is an immensely important activity for them. It’s not just how they get from place to place. It’s how they discover who they are, and how they find out about their world, connect to their ancestors, and maintain their cultural identity.

The Aboriginal Dreamtime in Australia is another wonderful example. This is a point that Michelle Sugiyama, of the University of Oregon, has made. Some of the stories these people tell are essentially navigational aids. It’s all about the act of exploratory locomotion.

You write at the end of the book that our species is threatened by “our filthy, deadly locomotive technologies.” Explain why you hate the automobile so much—and why a world of “self-generated propulsion” would be a much better place for our children?

There are lots of reasons for my hatred of motorcars [Laughs] Take the vast amount of deaths that they’re responsible for. The World Health Organisation has estimated 1.25 million people are killed in traffic accidents every year. And that doesn’t account for deaths due to pollution or inactivity leading to obesity. It’s also how they impact the psychological side of locomotion by making sure we can’t wayfare. Settlements end up being designed with the motorcar in mind, so more and more of us are living more and more distant from each other. We live and work in very different places. Family and friends are far away. All this makes us isolated.

Cars also break our link with our biological heritage. The idea of connecting to our ancestral past requires us to locomote as we are evolved to do, using our senses and making sure the mind and body are in union. Otherwise, it’s like our minds are passengers in our bodies. Travel time becomes wasted time.

I take it you don’t own a car?

[Laughs] No, I don’t. I’m very lucky living in Cambridge where I don’t have to. At least with a bicycle we are still engaging our muscles. Cycling also offers more options to go off on a tangent, which is what wayfaring locomotion is all about.

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Tuesday, April 26, 2016

How Puppeteers Brought BB-8 to Life in 'Star Wars: The Force Awakens'


Written by Sean Hutchinson

Here are all the BB-8 puppeteer GIFS you'll ever need.

There’s been an awakening. No, it’s not the Force. It’s the Blu-ray of Star Wars: The Force Awakens, which hit store shelves earlier this week, and is chock full all of the special features that come with the physical copy of the movie.

One of the most fascinating featurettes in the release is Building BB-8, a six-minute look into how everyone’s new favorite droid was primarily created using practical special effects. The little robot captivated audiences from the moment he popped up in the movie’s teaser trailer, causing entire websites to spring up to try and explain just how the geniuses behind the production made him work.

It turns out, BB-8 was brought to the screen by a team of many who used different versions of the droid to make the effect seamlessly edited into one performance. One was radio controlled, one was performed by a puppeteer who was erased using CGI technology later, while other versions of the practical BB-8 could simply just turn in place.

Because this is the Internet, the best (and only) way to show you a peek at the different versions of BB-8 is in GIF form. Check out the magic below.

The BB-8 puppet being dragged through the Jakku village.

A glimpse into BB-8's guts.

Scary prototype BB-8.

Who knew BB-8 came to life because of a dude in a blue sweatsuit?

Remote control BB-8

BB-8 puppeteer Brian Herring performed the practical effect on-set but was erased from shots in post production.

Photos via StarWars.com

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Electricity Basics: Resistance, Inductance & Capacitance


Written by Jim Lucas

Electronic circuits are integral parts of nearly all of the technological advancement in our lives today. Television, radio, phones and computers immediately come to mind, but electronics are also used in automobiles, kitchen appliances, medical equipment and industrial controls. At the heart of these devices are semiconductors — transistors, diodes and triodes. However, these devices could not function without much simpler components that predate semiconductors by many decades. These include resistors, capacitors and inductors.

Resistance

As its name implies, a resistor is an electronic component that resists the flow of electric current in a circuit. Electrical resistance is analogous to friction in a mechanical system. They both convert energy to heat and dissipate it to the surrounding environment, so electrical resistance can sometimes be thought of as a braking or damping mechanism in a circuit.

In metals such as silver or copper, which have high electrical conductivity and therefore low resistivity, electrons are able to skip freely from the conduction band of one atom to the next, encountering little resistance. However, in a material such as carbon, electrons encounter numerous collisions that make it more difficult for them to move through the material, according to Serif Uran, a professor of physics at Pittsburg State University. Insulators such as glass have extremely high resistivity, with virtually no spaces in their conduction bands that would allow electrons to move through them.

The electrical resistance of a circuit component is defined as the ratio of the applied voltage to the electric current that flows through it, according to HyperPhysics. The standard unit for resistance is the ohm, which is named after German physicist Georg Simon Ohm. It is defined as the resistance in a circuit with a current of one ampere at one volt. Resistance can be calculated using Ohm's Law, which states that resistance equals voltage divided by current, or R = V/I, where R is resistance, V is voltage and I is current. Ohm's Law is more commonly written as the equivalent expression V = IR. One way to understand Ohm's Law is to hold one of these variables constant, change the value of another variable, and watch what happens to the third variable. For instance, if we keep voltage constant and increase the resistance, the current must decrease. If we keep the resistance constant and increase the voltage, the current must increase.

Resistors are generally classified as either fixed or variable. Fixed-value resistors are simple passive components that always have the same resistance within their prescribed current and voltage limits. They are available in a wide range of resistance values from less than 1 ohm to several million ohms with tolerances ranging from plus or minus 0.1 percent to plus or minus 10 percent. Resistors are also classified by the maximum voltage they can tolerate as well as the maximum amount of power they can dissipate.

The resistance of a simple resistor can be calculated as R = ρL/A, where R is resistance, L is its length, A is its cross-sectional area and ρ is resistivity, which is an inherent property of the material. Resistivity is the reciprocal of conductivity σ, i.e., ρ = 1/σ. All other things being equal, a resistor that is twice as long will have twice the resistance, and one with twice the cross-sectional areal will have half the resistance. Also, material with higher resistivity will result in proportionally greater resistance.

Variable resistors are simple electro-mechanical devices, such as volume controls and dimmer switches, which increase the effective length of a resistor by turning a knob or moving a slide control. Strain gauges are resistors in which resistance changes with strain. Strain occurs when an object is stretched or compressed. A thermistor is a temperature sensor. It changes resistance when an increase in temperature excites electrons, making them available to conduct current, thus reducing the resistivity of the material. A piezoresistor changes its resistivity in response to a change in strain, which causes more or fewer electrons to be available to carry charge.

Inductance

An inductor is an electronic component consisting simply of a coil of wire. A constant electric current running through an inductor produces a magnetic field. If the current changes, so does the magnetic field. The unit for inductance is the henry (H), named after Joseph Henry, an American physicist who discovered inductance independently at about the same time as English physicist Michael Faraday. One henry is the amount of inductance that is required to induce one volt of electromotive force when the current is changing at one ampere per second.

Oersted’s Law, named after Danish physicist Hans Christian Oersted, states that a constant electric current generates a magnetic field around the conductor. Faraday’s Law of Induction states that a changing magnetic field induces a current in a conductor within that field. Finally, Lenz's law, named after Russian physicist Heinrich Lenz, states that this induced current is in the opposite direction of the change in current that produced the magnetic field. This phenomenon is called self-inductance.

What this means is, if you quickly reduce the current through the inductor, the changing magnetic field will induce a current that opposes the change, which tends to maintain the current at its previous level. Conversely, if you increase the current sharply, the induced current will be in the opposite direction of the increase, which again tends to maintain the current at a constant level. In other words, an inductor creates a kind of inertia in the current flow that resists rapid changes in much the same way that a massive body resists changes in its velocity.

One important application of inductors in active circuits is that they tend to block high-frequency signals while letting lower-frequency oscillations pass. Note that this is the opposite function of capacitors. Combining the two components in a circuit can selectively filter or generate oscillations of almost any desired frequency.

With the advent of integrated circuits, inductors are becoming less common because three-dimensional coils are extremely difficult to fabricate in two-dimensional layers produced by thin-film lithography. For this reason, microcircuits are designed to avoid using inductors, and instead use capacitors to achieve essentially the same results, according to Michael Dubson, a professor of physics at the University of Colorado Boulder.



Capacitance

Capacitance is the ability of a device to store electric charge. An electronic component that stores electric charge is called a capacitor. The earliest example of a capacitor is the Leyden jar. This device was invented to store a static electric charge on conducting foil used to line the inside and outside of a glass jar.

The simplest capacitor consists of two flat conducting plates separated by a small gap. The potential difference, or voltage, between the plates is proportional to the difference in the amount of the charge on the plates. This is expressed as Q = CV, where Q is charge, V is voltage and C is capacitance.

The capacitance of a capacitor is the amount of charge it can store per unit of voltage. The unit for measuring capacitance is the farad (F), named for Faraday, and is defined as the capacity to store one coulomb of charge with an applied potential of one volt. One coulomb (C) is the amount of charge transferred by a current of one ampere in one second.

In practice, it would take a huge capacitor to store one coulomb of charge at one volt. The capacitance of a simple parallel-plate capacitor is equal to the permittivity of free space times the area of the plates divided by the distance between them, or C = ε0A/d, where C is the capacitance, A is the area of the plates, d is the separation between the plates, and ε0 (epsilon naught) is the permittivity of free space which is equal to 8.58 × 10−12 F/m.

A one-farad capacitor made of two flat metal plates with 1 mm of air space between them would be about 113 square kilometers (43.6 square miles). Fortunately, there are better ways to make capacitors that are much more space-efficient than this. In practice, plates are stacked in layers or wound in coils and spaced much more closely than 1 mm. They also use dielectric materials between the plates that work much better than an air gap. Dielectrics are insulating materials that allow for close spacing between the plates, and they partially block the electric field between the plates in proportion to their dielectric constant, which is a measure of the material's relative permittivity compared to that of free space. This allows the plates to store more charge without arcing and shorting out. Interestingly, for a transparent material, such as glass or diamond, its dielectric constant is essentially the same as its refractive index which is the ratio the of speed of light in vacuum (c) to the speed of light in that material.

Capacitors used in electronic circuits are typically measured in microfarads (μF), nanofarads (nF) and picofarads (pF), which are millionths, billionths and trillionths of a farad, respectively. However, larger capacities can be achieved using thin film deposition to produce dielectric layers that are only a few atoms thick.

Capacitors are often found in active electronic circuits that use oscillating electric signals such as those in radios and audio equipment. They can charge and discharge nearly instantaneously, which allows them to be used to produce or filter certain frequencies in circuits. An oscillating signal can charge one plate of the capacitor while the other plate discharges, and then when the current is reversed, it will charge the other plate while the first plate discharges. In general, higher frequencies can pass through the capacitor, while lower frequencies are blocked. The size of the capacitor determines the cut-off frequency for which signals are blocked and which are allowed to pass. Capacitors in combination can be used to filter selected frequencies within a specified range.

Supercapacitors are manufactured using nanotechnology to create super-thin layers of materials such as graphene to achieve capacities that are 10 to 100 times that of conventional capacitors of the same size; however, they have much slower response times than conventional dielectric capacitors, so they cannot be used in active circuits. Compared to batteries, though, these devices have extremely fast charging times, and they can withstand thousands of charging cycles. Their main disadvantage is that they are considerably larger than batteries for the same amount of stored energy. Also, supercapacitors can only operate at low voltages, generally less than four volts; however, like battery cells, they can be connected in series to provide higher voltages.

Putting them all together

Inductors, resistors and capacitors are often combined in what are commonly called RLC circuits to generate or receive oscillating signals of specific frequencies. Interestingly, their behavior can be modeled using the exact same mathematics as for simple harmonic motion of a damped mass–spring system. In this case, the resistance R is analogous to friction; the inductance L is analogous to the mass; and the capacitance C is analogous to the spring constant. In both cases, the system will have one specific resonant frequency at which it will naturally tend to oscillate.

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Monday, April 25, 2016

Mysterious Plain of Jars Site Holds Human Remains


Written by Tom Metcalfe

An ancient burial site, including an oddly shaped quartz stone covering the face of one of the newly uncovered human skeletons, has been discovered at the mysterious Plain of Jars, an archaeological site in remote central Laos littered with thousands of stone vessels.

The new findings could help researchers solve the long-standing puzzle of why the stone jars were scattered across this part of Laos.

When it was found, the skull beneath the quartz adornment appeared to be looking through a large hole in the stone, said Dougald O’Reilly, an archaeologist at the Australian National University (ANU), who led a team of scientists on a joint Laos-Australian expedition to the Plain of Jars in February.

"When we excavated it, the skull was actually looking out through that perforation. It was quite interesting, but whether it was done purposefully is difficult to know," O’Reilly told Live Science.

Ancient burials

The burial site is estimated to be 2,500 years old, and was found when researchers from ANU, Monash University in Australia and the Laos Ministry of Information, Culture, and Tourism, spent four weeks mapping and excavating the ground around a group of the massive carved stone jars that dot the landscape.

More than 90 jar sites — some with up to 400 stone jars measuring as tall as 10 feet (3 meters) high — are spread across foothills, forests and upland valleys of this remote region.

The members of the Laos-Australian expedition worked at the most accessible site, known as Jar Site 1, located a few miles outside the city of Phonsavan, in Xiangkhoang province in central Laos. The researchers plan to explore a second, more remote jar site next year.

The Laos government hopes to develop Jar Site 1 as an archaeological center and UNESCO World Heritage site, to protect the unique Plain of Jars landscape and to stimulate scholarship and cultural tourism in the area.

Mysterious jars

O’Reilly said the latest expedition was the first major effort by archaeologists since the 1930s to visit the site, in an effort to understand the purpose of the jars and who created them. Since that time, however, some archaeologists have undertaken important work at the Plain of Jars, mainly on their own.

The latest team of around 11 researchers worked together to compile the first comprehensive scientific study of one of the jar sites, including a GIS (geographic information system) map recording the precise location of each of the jars, stone disks and quartz stone markers scattered over the site.

The largest jars weigh more than 10 tons (9,000 kilograms), and a big part of their mystery is how they got there.

"There are a few well-known quarry sites where the jars were sourced and then brought across the landscape, about 8 to 10 kilometers [5 to 6 miles] to the jar sites," O'Reilly said. "So there's a huge amount of effort involved in moving them — one would have to speculate that elephants must have been involved, given the incredible weight of the jars."

And carving the massive jars would have been no easy task for primitive peoples with iron tools, he added.

"Some of the jars are over 2 meters [6.5 feet] or perhaps even 3 meters [10 feet] in height, and in girth you couldn't get your arms around most of them," O'Reilly said. "And there are variations in the design of the jars: some have larger or smaller openings, some are rectangular, some circular or oval — in some cases you wonder how did they even carve these things?"

The variety of sizes and shapes of the jars has prompted many researchers to theorize about their purpose over the years.

"It’s probably likely that they do represent a memorial of some kind, and the variations in the sizes of the jars may indicate that there were differences in status and perhaps a hierarchy in the society that created the jars," O'Reilly said. "You could spend a lot of time theorizing."

Unearthing new mysteries

The burial site with the oddly shaped quartz stone was one of three distinct types of burial sites found at Jar Site 1, the researchers said.

"This is the first time that this type of interment has been uncovered at the Plain of Jars, but if there is one, there will probably be others," O'Reilly said. "And this burial is also quite interesting because it contained the remains of not one but two individuals: the cranial bones of what's estimated to be an 8-year-old child were found in that burial as well [as an adult skeleton]."

The expedition also uncovered 11 ceramic jars, which are expected to contain "secondary" burials of human bones from which the flesh was removed. A pit filled with bones from several secondary burials and covered with a large limestone block was also found, and the marker stones and stone disks on the ground around the stone jars seemed to correspond to the location of secondary burials, O'Reilly said.

Scientific study of samples and remains from the Plain of Jars site will continue in the laboratory. O’Reilly said the expedition recovered some human teeth that could provide DNA for testing and clues to the origins of the ancient peoples buried there. But, DNA tends to degrade heavily in the climate conditions of Southeast Asia, so a proper analysis might not be possible, he added. The contents of the ceramic jars excavated from the site will also be carefully examined to confirm if, as the researchers suspect, they hold human remains.

But the Plain of Jars is not giving up all its secrets just yet. Although some archaeologists have proposed that the stone jars were used to decompose bodies before the bones were cleaned for secondary burials, it may be impossible to know for sure.

"This is something you find in various religious practices in different parts of the world, but it's something that needs to be investigated a little further at the Plain of Jars," O’Reilly said.

One of the biggest problems at the site is that the jars have been exposed to the harsh Southeast Asian climate for more than 2,000 years, making it very difficult for scientists to study and run test on the artifacts.

"Possibly we could look at trying to extract lipids from the stone jars to see if there is any evidence for decomposition of human remains, but the jars have been exposed for so long that it's a bit of a long shot," he said. "So, I fear we probably will never know the true purpose of the large stone jars."

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What prehistoric wisdom teeth tell us about human evolution


Written by Michael Holtz

Paleontologists have long wondered why human wisdom teeth are so much smaller than those found in fossils of homonin species. A team of evolutionary biologists say they have solved the mystery.

Researchers have discovered that the evolution of human teeth is much simpler than previous thought.

For years scientists have debated the evolution of our third molars, more commonly known as wisdom teeth. While the molars are often very small or fail to even develop in humans, those of other hominin species in our evolutionary tree were huge. Their chewing surfaces could be two to four times larger than those in an average modern human.

Many scientists have long tried to explain the profound size change to dietary and cultural shifts considered to be unique to humans. Think cooking, for example.

But a new study, published this week in the journal Nature, by a team of researchers led by evolutionary biologist Alistair Evans of Monash University in Australia offers an explanation that make us appear far less special.

“Teeth can tell us a lot about the lives of our ancestors, and how they evolved over the last 7 million years,” Professor Evans said in a press release. “What makes modern humans different from our fossil relatives?”

Evan says that paleontologists have worked for decades to interpret these fossils and look for new ways to extract more information from teeth. Rather than viewing their evolution as the result of human-specific selective pressures, he proposes that the shrinking of wisdom teeth may be explained by basic developmental mechanisms that we share with most mammals.

Evan’s research confirms that molars follow the sizes predicted by what is called “the inhibitory cascade,” a rule that shows how the size of one tooth affects the size of the tooth next to it. As the authors conclude in the study:

Whereas selective pressures emphasizing function, such as changing bite force, have been used to explain the variation in tooth proportions, only by including development can one explain the details of the changes. By providing a development-based expectation for the evolution of the hominin dentition, the inhibitory cascade framework moves this research towards a predictive science, further testable with additional fossils.

“Our new study shows that the pattern is a lot simpler than we first thought – human evolution was much more limited,” Evans said.

Click here to read more.

Friday, April 22, 2016

Watch an Eagle Battle a Cobra in Dramatic New Video


Written by Brian Clark Howard

See which animal wins a high-stakes encounter in South Africa's Kruger park.



Like a scene out of the Jungle Book, an epic skirmish between an eagle and a cobra was caught on video by visitors to Kruger National Park in South Africa.

Uploaded online on Tuesday, the video was taken by Matthew McCreesh and Catherine van Eyk, both 26, of South Africa.

"Wow! What an incredible video," says Rowen van Eeden, a Cape Town-based behavioral ecologist and National Geographic explorer who studies Kruger's wildlife.

Such encounters are rarely seen, and even more rarely filmed, says van Eeden, a Ph.D. candidate at the University of Cape Town who is studying the decline of martial eagles in Kruger.

"As the eagle and cobra surreptitiously circle each other, the mighty bird tries to make a move on the deadly snake—before flapping his feathers as the cobra spits out poisonous venom," wrote the pair who uploaded the video.

"They continue to stare each other out—before the eagle eventually admits defeat and flies off."

The bird is most likely a brown snake eagle (Circaetus cinereus), trying to prey on a snouted cobra (Naja annulifera), says van Eeden. The snouted cobra can be identified by the dark banding on its throat, says South African herpetologist Johan Marais.

And although the voices heard in the video (and their written description) suggest the cobra is spitting, most likely it is actually making mock strikes, say van Eeden and Marais. Snouted cobras don't typically spit.

The largest of the snake (or serpent) eagles, brown snake eagles can weigh up to 5.3 pounds (2.4 kilograms) and have wingspans up to 5.3 feet (1.6 meters).

"They typically eat their prey whole, and there are records of them predating on even the most venomous of snakes, such as the renowned black mamba," says van Eeden.

Snouted cobras can reach a length up to 8.2 feet (2.5 meters) and pack powerful neurotoxic venom, which attacks the nervous system. A bite can be fatal in human beings.

Battles between the eagle and snake species are likely relatively common, although they are rarely seen by people, says Luke Dollar, a conservation biologist who often works in Africa and who manages National Geographic's Big Cats Initiative. That's partly due to recent declines in the number of brown snake eagles, which have seen their population shrink by 50 percent over the past two decades.

"The cobra looks to me to be already taxed or injured in some way, it's not moving very quickly," Dollar adds.

Snake eagles typically attack their prey from a perch, hitting it with considerable force and using their sharp talons to inflict damage. Yet the eagles are not immune to snake venom and rely on their speed and power to avoid bites. Another risk is getting trapped in the snake's coils, which may allow the cobra to overpower its attacker. The eagle's strategy is often to tire the snake out until it can strike the reptile in the back of the head.

Snake eagles are occasionally seen with necrotic legs after their battles with venomous snakes.

"It looks like the eagle is being really careful," says snake ecologist Matt Goode of the University of Arizona, another National Geographic explorer.

"The snake's venom is definitely nothing to mess with."

Click here to read more.

Great Dane to Chihuahua: How Do We Know Dogs Are the Same Species?


Written by Laura Geggel

If aliens visited Earth tomorrow, would they realize that dogs — from the spotted dalmatian, to the giant Great Dane, to the tiny Chihuahua — are all the same species?

Forget aliens, said Jack Tseng, a paleontologist at the American Museum of Natural History in New York. If we hadn't actually bred dogs ourselves, even humans would have a hard time determining that a Cavalier King Charles spaniel and a wolfhound are related, he said.

"If you were a biologist who comes from a society that never had any dogs associated with humans and you looked at these dogs, you would immediately think that these were different species," Tseng told Live Science.

Typically, researchers rely on anatomy and genetics to determine whether animals belong to the same species. But because of their varied shapes and sizes, anatomy is relatively useless when comparing different breeds of dogs, he said. Even dogs' teeth, though similar in structure, come in so many sizes that it would be difficult to determine that they're from the same species, Tseng said.

"It's a good example of how much you can tweak the same genetic blueprint and have animals that look so different still be the same species," he said.

Instead, genetic analyses tell us that all dogs are the same species, Tseng said.

But, by those standards, dogs and gray wolves (Canis lupus) are also the same species, as the two share most of the same genes. There's still debate about whether to call dogs Canis lupus familiaris, suggesting that they are a subspecies of the wolf, or Canis familiaris, a distinct species from the wolf, Tseng said.

Despite their similar genes, the two do have some different gene variants, known as alleles. For instance, a variant of the gene IGF1 is associated with body size. One IGF1 variant is linked to small body size in dogs, but it's not found in wolf populations, according to a 2010 study published in the journal BMC Biology.

Another clue that all types of dogs are the same species is that they can reproduce with one another. Technically, different dog breeds can have puppies together, although Tseng said he is "not aware of actual examples where people have tried to cross dog breeds that are dramatically different in size — imagine [a] Great Dane and [a] Chihuahua."

However, domestic dogs can also breed successfully with wolves — a fact that supports the idea of classifying dogs in the same species as wolves, Tseng said.

Still, wolves and dogs have subtle differences in their anatomy. Dogs have more prominent, raised foreheads than wolves do, he said. Domestic dogs also tend to have shorter faces and more crowded teeth as a result of that, he said.

"They have the same number of teeth as wolves, but there's less space to put the teeth in," Tseng said. "The teeth sometimes reduce in size, but also sometimes get rotated a little bit so they can fit more of them in the mouth."

Despite these minor differences, genetic data — especially mitochondrial DNA, which gets passed down through the maternal line — suggest that all dogs are the same species, and that wolves likely are, too. But from a societal standpoint, wolves and dogs are extremely different.

"Based on what we know about them as scientists and pet owners, [dogs] have definitely become something different from just wolves," Tseng said.

Click here to read more.

Thursday, April 21, 2016

A Computer Painted This Rembrandt


Written by Andrew Moseman

The hat. The color. The collar. The texture. The painting has all the hallmarks of a portrait by 17th century Dutch master Rembrandt van Rijn, but this work of art is the work of a machine.

"The Next Rembrandt," unveiled this week in Holland, is the result of an 18-month project by Amsterdam advertising agency J Walter Thompson, working for ING Bank with the help of some people from Microsoft. And it is, of course, not a Rembrandt at all. Project head Bas Korsten and his team built a new kind of software with a facial recognition algorithm and let it loose studying the works of the legendary artist, with the hope the machine could understand the brushstrokes of the man.

The system studied 346 Rembrandts in all. It was then hooked up to a 3D printer that became the artificial artist's medium, laying down 13 layers of "paint-based UV ink" in a way that mimics not only the layout and palette of a Rembrandt but also the three-dimensional physical structure of the painting.

Not surprisingly, some fans of the Dutch master aren't wild about a machine copying his style. But Korsten insists the "New Rembrandt" is a tribute, not a forgery. He tells The Guardian, "We are creating something new from his work. Only Rembrandt could create a Rembrandt."



Click here to read more.

Culling to Conserve: A Hard Truth for Lion Conservation


Written by Michael Schwartz

People that don’t live in Africa tend to learn about wildlife conservation in easy-to-understand terminology. But safeguarding animal species like lions is often more complex than mainstream media sound bites would have their audiences believe.

The National Post recently reported that management from Zimbabwe’s Bubye Valley Conservancy was considering a controversial move to cull upwards of 200 lions out of a rough population of 500 in order to ensure the reserve’s wildlife biodiversity.

It was also reported that since the growing calls to end trophy hunting, due in large part to the killing of Cecil the lion in Zimbabwe’s Hwange National Park last year, conservancies like Bubye are no longer seeing the funding necessary to adequately cover conservation costs, which includes fence maintenance, financing local schools and health clinics, and providing meat to local people.

Given the many challenges conservationists face in Africa, coupled with culling and trophy hunting being such contentious issues, I decided to reach out to Dr. Byron du Preez, a Bubye Valley Conservancy project leader and member of the Wildlife Conservation Research Unit (WildCRU), in the Department of Zoology at Oxford University.

Specifically, I was hoping for clearer answers regarding the potential paradox that increasing calls for hunting bans in Africa have on existing lion populations, and how that may be playing out within the recent culling conundrum.

Fortunately, Du Preez went one step further by clearing up what was initially reported, clarifying the proposed cull, explaining how culling works, and elaborating on the dangers of promoting single species management.

The following is his official statement:

Clarification on the Proposed Lion Cull

I am an independent scientist working on the Bubye Valley Conservancy, focused on lion ecology, which actually means just about every aspect of the ecosystem, such is the influence that lions have. I am neither pro- nor anti-hunting. I simply focus on practical conservation solutions that actually work in the real world.

We are hopeful that we will be able to translocate some lions, although all previous attempts to translocate lions out of the Bubye Valley Conservancy have been derailed by factors entirely out of our control. However, if the species was in as much trouble as the sensationalist reports like to focus on, one would think that it would be a lot easier to find new homes for these magnificent animals than it actually is.

‘There is basically no more space left in Africa for a new viable population of lions.’

The fact remains that habitat destruction is their biggest enemy, and there is basically no more space left in Africa for a new viable population of lions.

The Science of Culling

A cull is not a once-off fix (neither is translocation, nor contraception), but would be more of an ongoing management operation conducted on an annual basis. When given adequate space, resources, and protection, lion populations can explode, such as they have done on the Bubye Valley Conservancy.

Reducing numbers to alleviate overpopulation pressure does nothing to permanently solve the problem, nor halts the species’ breeding potential; [it] only slows it down for a relatively short time until their population growth returns to the exponential phase once again.

Culling is a management tool that may be used for many species. That includes: elephants, lions, kangaroos, and deer, basically animals that have very little natural control mechanisms other than disease and starvation, and that are now bounded by human settlements and live in smaller areas than they did historically.

As responsible wildlife managers who have a whole ecosystem full of animals to conserve (not just lions), we have therefore discussed culling as an option for controlling the lion population, but have agreed that, for now, this is not necessary just yet and we will continue to try and translocate these animals until our hand is forced.

As already mentioned, there is very little space left in Africa that can have lions but doesn’t already. Also, where lions do occur, especially in parks and private wildlife areas, they often exist at higher densities than they ever did historically.

This is mainly due to augmented surface water supply resulting in greater numbers of non-migratory prey that now no longer limit lion nutrition and energy availability, allowing the lion population to rapidly expand.

For example, successful hunting to feed cubs all the way through to adulthood and independence is one of the greatest stresses for a lion, and often results in dead cubs and reduced population growth. In turn, a high density of lions can severely reduce the density of their prey, ultimately leading to the death of the lions via disease and starvation—far more horrific than humane culling operations conducted by professionals.

The Dangers of Single Species Management

Lions are the apex predator wherever they occur, and as such exert a level of top-down control on the rest of the ecosystem. Lions prey on a wide variety of species, and we are starting to see declines in even the more common and robust prey such as zebra and wildebeest—not to mention the more sensitive species such as sable, kudu, nyala, warthog, and even buffalo and giraffe.

Apart from their prey, lions are aggressively competitive and will go out of their way to kill any leopard, cheetah, wild dog, or hyena that they encounter, and have caused major declines in these species, not just on the Bubye Valley Conservancy, but elsewhere in Africa where lion densities are high.

According to the International Union for the Conservation of Nature (IUCN), cheetah are listed as vulnerable, and wild dogs are endangered.

It is easy to simply focus on the number of lions remaining in Africa that has fallen steeply over the last century from ~100,000 to ~20,000 today, but which is directly linked to the reduction in available habitat.

Simply focusing on increasing the abundance of one species at the cost of another cannot be considered a conservation success—assuming that holistic conservation for the benefit of the entire ecosystem is the end goal—no matter how iconic that species is.

Luckily, lions kill lions, resulting in more lion mortality than any other species—including man on the Bubye Valley Conservancy—and in an ideal world the lion population would level off at a putative carrying capacity where lions control their own numbers (deaths from conflict equal or exceed new births). However, it is possible and probable (man-made water points increase the carrying capacity of — and therefore also the competition and conflict between — all wildlife species) that this would still be at the cost of certain other sensitive species.

Ecosystem stability is related to size (and conversely ecosystem sensitivity is inversely related to size) and smaller areas need to control their lion numbers a lot more carefully than large areas such as the Bubye Valley Conservancy, which is over 3,000 square kilometres [1,160 square miles]. In fact, small reserves in South Africa alone culled over 200 lions in total between 2010 and 2012 ,according to the 2013 report from the Lion Management Forum workshop.

Understanding Carrying Capacity

The Bubye Valley Conservancy does not rely on trophy hunting to manage the lion population. I will discuss the economics of hunting in brief. The most recent and robust lion population survey data calculate a current lion population on the Bubye Valley Conservancy of between 503 and 552 lions (it is impossible to get a 100 percent accurate count on the exact lion number — which also changes daily with births and deaths).

Carrying capacity is an extremely fluid concept, and changes monthly, seasonally, and annually depending on all sorts of factors including rainfall, disease (of both predator and prey), and economics.

It is estimated that 500 lions eat more than U.S. $2.4 million each year (the meat value used is a very conservative $3 per kg – compare that to the price of steak in a supermarket, and then remember that the Bubye Valley Conservancy used to be a cattle-ranching area, and if wildlife becomes unviable, then there is no reason not to convert it back to a cattle ranching area once again).

To give the question of carrying capacity a fair, if necessarily vague, answer, I would personally estimate that the upper carrying capacity of lions on the Bubye Valley Conservancy would be around 500 animals—assuming that they are allowed to be hunted and therefore generate the revenue to offset the cost of their predation.

Remember, lion numbers can get out of hand. And if there was no predation, then thousands upon thousands of zebra and wildebeest and impala would need to be culled to prevent them from over grazing the habitat, leading to soil erosion, starvation, and disease.

The ecosystem is a very complex machine and whether anyone likes it or not, humans have intervened with cities, roads, dams, pumped water, fences, and livestock. The only way to mitigate that intervention is by further, more focused, and carefully considered intervention, for the sake of the entire ecosystem.

It is important to bear in mind that the wildlife here, and in the majority of other wildlife areas in Africa (hunting areas exceed the total area conserved by Africa’s national parks by more than 20 percent), does not exist as our, or anyone else’s, luxury.

The Bubye Valley Conservancy is a privately owned wildlife area, or to put it another way, it is a business. The fact that it is a well-run business is the reason why it is one of the greatest conservation successes in Africa, converting from cattle to wildlife in 1994 (only 22 years ago) and now hosting Zimbabwe’s largest contiguous lion population at one of the highest densities in Africa, as well as the third largest black rhino population in the world (after Kruger and Etosha).

This is only possible because it is a business, and is self-sufficient in generating the funds to maintain fences, roads, pay staff, manage the wildlife, pump water, and support the surrounding communities—all extremely necessary factors involved in keeping wildlife alive in Africa.

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Wednesday, April 20, 2016

Green Sea Turtles of Florida, Mexico No Longer Endangered


Written by Kerry Sheridan

Green sea turtles of Florida and the Pacific coast of Mexico are no longer considered “endangered,” US officials said Tuesday, hailing decades of conservation work for saving the long-imperiled creatures.

Breeding populations on the beaches of Florida and the west coast of Mexico are now described as “threatened” and still merit protection under the Endangered Species Act, but do not face an imminent risk of extinction, the US Fish and Wildlife Service said.

In Florida alone, there are some 2,250 nesting females counted on beaches each year, up from only a handful in 1978 when the breeding populations were first listed as endangered, an FWS spokesman said.

As part of the change, the US FWS and the National Oceanic and Atmospheric Administration (NOAA) Fisheries divided green sea turtles (Chelonia mydas)globally into 11 distinct population segments, “allowing for tailored conservation approaches for each population,” the agencies said in a statement.

That leaves three populations of green sea turtles worldwide that are considered endangered and at the highest risk of disappearing from the planet — those that live in the Mediterranean Sea as well as the Central South Pacific and Central West Pacific Ocean.

Most of the world’s populations of green sea turtles are listed as “threatened.”

The changes were initially proposed last year and made final on Tuesday after officials reviewed the scientific data and an outpouring of more than 900 public comments.

“Successful conservation and management efforts developed in Florida and along the Pacific coast of Mexico are a roadmap for further recovery strategies of green turtle populations around the world,” said Eileen Sobeck, assistant NOAA administrator for fisheries.

Sea turtles have long faced a host of threats, from beach development that destroyed their nesting habitat, to pollution, to fishing nets that entangled them.

Successful measures have included protection of nesting beaches, reduction of bycatch in fisheries and prohibitions on the direct harvest of sea turtles, NOAA said.

Officials at NOAA estimate that there are currently 571,220 nesting female green sea turtles around the world.

The largest population, including more than 167,000 females, lives in the North Atlantic.

By contrast, among the endangered populations, between 404 and 992 are believed to live in the Mediterranean, and just over 9,000 in the Central West and Central South Pacific, a spokeswoman for NOAA said.

Challenges remain, including climate change and sea level rise that may erode beach nesting habitat and raise the temperature of sand, which can “result in skewed sex ratios and lethal incubation conditions,” the agencies noted in a 134-page document in the federal register.

Some commenters raised concern about a herpes-related virus called fibropapillomatosis, or FP, which is common among young green sea turtles in warmer waters, and can cause fatal tumors.

“We acknowledge the increasing distribution and incidence of FP, particularly in Florida. The threat is likely to increase” along with human-driven pollution of the shores, the agencies said.

Dangerous fishing gear and boat strikes also kill significant numbers of turtles each year.

“Sea turtles face a lot of threats, from plastic trash they swallow to sea-level rise to getting caught in fishing gear -— even poaching, in some parts of the world,” said Catherine Kilduff of the Center for Biological Diversity.

“The undeniable recovery of most green sea turtle populations creates a hopeful spot in our changing oceans.”

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25 scientific images so gorgeous you can't even handle it


Written by Jefferson Reid

If you think microscopes and scanners can't produce beautiful art, you're so, so wrong.

Every year, the Federation of American Societies for Experimental Biology runs the BioArt contest. Researchers worldwide submit images culled from their latest projects, and the winners are as gorgeous as they are scientifically significant.

For example, studying infant nutrition is a beautiful thing, in both the literal and figurative sense at the Arkansas Children's Nutrition Center. Dr. Xiawei Ou's team used diffusion tensor imaging tech to non-invasively capture this multi-colored marvel, a 3-D visualization of brain nerve fiber bundles interconnecting.

Click here to see all 25 pictures.

Tuesday, April 19, 2016

MIT researchers are now 3D printing robots that can walk on their own


Written by Matt McFarland

For years, 3D printing has been hailed as an emerging technology likely to transform our lives. Researchers at MIT’s Computer Science and Artificial Intelligence Laboratory have taken the nascent field to a new level with the creation of 3D printed robots made of both solids and liquids.


Previously, 3D printing had only been done with solid materials. Printing with both materials allows for the faster creation of complex designs, lessening the time and expense required to make robots. Inexpensive robots could make remote exploration — or any activity where a robot is used — more affordable, bringing broad implications for the utility of robots.

“It makes a big difference in what kind of machines you can make,” said professor Daniela Rus, who oversaw the project. “If you can make complex robots really fast — print them like you print a piece of paper — you can imagine not having to worry so much about whether you lost your robot.”

The MIT team used the method to print hydraulic bellows that were filled with fluid. After adding a battery, sensors and computer to their small hydraulic robots, the robots could walk independently.

Rus said her team plans to expand and improve its work before commercializing the technology. Their current process took 22 hours to create the six-legged, 1.5-pound robots with a commercially available 3D printer — costing more than $100,000 — that they modified.


The printer — a Stratasys Objet260 Connex — wasn’t built to use liquids in the 3D printing process. So the researchers essentially hacked the machine, inserting a different computer chip in the cartridge holding their liquid of choice — the machine’s cleaning fluid — so that the 3D printer thought it was actually printing plastic, not liquid.

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Fabrics unearthed from King David's time offer peek at biblical fashion


Written by Leslie Katz

Arid conditions in Israel's desert copper mines allow a treasure trove of ancient textiles to survive. Talk about vintage clothes.

What would have graced the cover of Vogue in ancient Israel?

An extensive collection of fabrics uncovered in the country's southern desert copper mines offers a tangible glimpse. The textiles, excavated by a team from Tel Aviv University, mark the first discovery of materials from the era of Kings David and Solomon some 3,000 years ago, according to Israel's Foreign Ministry.

"No textiles have ever been found at excavation sites like Jerusalem, Megiddo and Hazor, so this provides a unique window into an entire aspect of life from which we've never had physical evidence before," Erez Ben-Yosef, the Tel Aviv University archaeologist who led the excavation in late January and February, said in a statement Wednesday. "We found fragments of textiles that originated from bags, clothing, tents, ropes and cords."

Far from the drab undyed sheep's wool of many a biblical reenactment, the fabrics vary in color, weaving and ornamentation to present a more complex, runway-friendly picture of the day's fashion. One wool fragment is dyed red and blue, for example, with natural animal hair of other colors woven into decorative bands that would have no doubt looked chic skimming a pair of bygone Birkenstocks.

The fabrics, found in Timna, in Israel's southern Arava Valley, also offer insight into the trade practices and regional economy of the day. Many of the textiles, including linen, were woven far from the copper mines, some of which are thought to have been active during the reign of King Solomon, around the 10th century BCE. That linen was imported, likely from Northern Israel or the Jordan Valley, the researchers say, bolsters the picture of an active copper production culture in need of daily goods that existed in Israel's desert to provide metal for valuable tools and weapons.

"The possession of copper was a source of great power, much as oil is today," Ben-Yosef said. "If a person had the exceptional knowledge to create copper, he was considered well-versed in an extremely sophisticated technology."

The fabric discoveries are part of the larger Central Timna Valley Project, an ongoing multidisciplinary effort started in 2012 to explore the archaeological record of the southern Arava's copper mining and smelting sites. Arid conditions in the area have helped organic materials such as fabric and leather survive. Give it a few more years. With the cyclical nature of fashion, we might just see Davidian garb on the catwalk.

Click here to read more.

Monday, April 18, 2016

Inside The Painful History Of The First Baseball Glove


Written by Matt Giles

Bet that felt padding didn’t do much for comfort.

April 4th is the official opening day of the 2016 Major League Baseball season, and Popular Science is celebrating the occasion by looking back at the first ever patent for the baseball glove. It was filed in 1885 by George R. Rawlings, who owned a St. Louis sporting goods' store and wanted to create a device that used felt and padding to protect the fingers and palms of those who were flocking to the relatively new sport, which became popular during the Civil War.


Glove patent design
The original design of the baseball glove, from September 1885.


Popular Science first wrote about the baseball glove in an issue from January 1896. The article, which is titled, 'The Ball Can't Drop Out of This Glove', highlights the technological advances that were already spinning the game forward. Or, if not forward, at least in an interesting direction:

Major Robert H. Young, of the United States Air Service, has invented a baseball glove that swallows this compressed air, creating a partial vacuum in the glove and eliminating the tendency to rebound. There are air holes in the padded palm to which flexible tubes are attached. These tubes have their outlets in the sides of the glove. There are valves at the end of the tubes that prevent air from entering.

Major Robert H. Young, the Billy Beane of the 19th century.

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What Do Dogs Dream About?


Written by Stephanie Pappas

When Fido's legs twitch in his sleep, is he really dreaming of chasing rabbits?

Probably, researchers say. The "rabbits" part is up for debate, but the scientific evidence strongly suggests that not only do dogs dream, but they likely dream about waking activities, much like humans do.

"Dogs do dream," said Stanley Coren, a professor emeritus of psychology at the University of British Columbia and the author of "Do Dogs Dream? Nearly Everything Your Dog Wants You to Know" (Norton, 2012).

Dogs sleep more than people do, Coren told Live Science, and they have a particular penchant for catnaps. But the structure of their sleep looks remarkably human: Like humans, dogs cycle through stages of wakefulness, rapid-eye-movement (REM) sleep and non-rapid-eye-movement sleep. Scientists reporting in the journal Physiological Behavior in 1977 recorded the electrical activity of the brains of six pointer dogs for 24 hours, and found that the dogs spent 44 percent of their time alert, 21 percent drowsy and 12 percent in REM sleep. They also spent 23 percent of their time in the deepest stage of non-REM sleep, called slow-wave sleep.

People dream in both REM and non-REM sleep, but the dreams that most people remember are REM dreams. In this stage, dreams are memorable and often bizarre. Plus, people are more likely to awaken right after REM sleep than after non-REM sleep, said Matthew Wilson, a cognitive scientist who researches learning and memory at the Massachusetts Institute of Technology. By comparison, non-REM dreams are rather mundane, Wilson told Live Science.

Resting rats

In 2001, Wilson and his colleagues were the first to find that rats dream — or, at least, their brains do the same thing people's brains do during dreaming, and to similar effect. First, the researchers recorded the activity of multiple neurons in the rats' brains while they did repetitive maze tasks. Next, they recorded the same neurons during REM sleep.

In 44 percent of REM sleep episodes, the researchers found brain patterns that matched those that the rats had produced during their waking maze runs. The patterns lasted for minutes at a time and "played" at the same rate as they did when the rats were awake. In other words, the animals seemed to be reliving their waking activities in REM sleep, the researchers reported in 2001 in the journal Neuron.

The next year, Wilson's group reported similar brain activity echoes of daily life in rats' non-REM sleep. But in non-REM sleep, the brain-wave patterns were shorter and faster, instead of mimicking real time, and the patterns showed up only in naps right after the real-world activities.

Still, there's evidence that these non-REM activity bursts are dreamlike for rats, just as similar brain activity is dreamlike (but forgettable) in humans. Wilson and his colleagues found that while these telltale neurons were firing in the hippocampus — the wrinkly blob of brain at the base of the skull that's linked to memory and learning — neurons in their visual cortex were firing, too.

"They were 'seeing' what the hippocampus was dreaming about," Wilson said.

Dreaming dogs

The finding that rats dream is a good indication that dreaming is common across mammals. In fact, non-REM sleep is seen in all vertebrates (animals with backbones) and may even extend to some invertebrates, like fruit flies. Thus, even flies may dream in some form, Wilson said.

The reason the dreamy brain patterns of REM and non-REM sleep are so common seems to have something to do with their role in learning and memory. Sleep boosts memory formation, and disrupted sleep can impede memory.

Sleep "adds something" to the process of learning and remembering, Wilson said. Patterns in non-REM sleep seem to suggest a sort of categorizing of the day's activities. REM sleep, on the other hand, may be an avenue for the brain to explore in a consequence-free environment.

"The idea is that, in sleep, the brain is trying to find shortcuts or connections between things that you may have experienced but you just hadn't put them together," Wilson said. The bizarre sleep imagery of REM dreams could be a manifestation of this deeper process, he said.

But back to those snoozing Saint Bernards and Scottish terriers. Dogs enter REM sleep about 20 minutes into a snooze session, and might stay there for 2 or 3 minutes. An observant owner might notice the animal's breathing become irregular, Coren said. In puppies and very old dogs, the muscles might twitch. In both dogs and humans, part of the brain stem called the pons is responsible for paralyzing the large muscles during sleep, which keeps people and pets alike from acting out their dreams. The pons is underdeveloped in puppies and may not work as efficiently in old dogs, Coren said, which is why these pooches are more likely to twitch than dogs in their middle years. (The same is true of very young and very old humans.)

Studies in which the muscle-paralyzing part of the pons has been temporarily deactivated are the only way to peek into doggy dreams. With the pons offline, dogs start to act out their dreams (in humans, this condition is called REM sleep disorder).

"What we've basically found is that dogs dream doggy things," Coren said. "So, pointers will point at dream birds, and Dobermans will chase dream burglars. The dream pattern in dogs seems to be very similar to the dream pattern in humans."

For unknown reasons, the size of the dog may determine the size of the dream. Smaller dogs have more frequent but shorter dream periods, Cohen said, while large dogs have less frequent but longer dreams.

Dog sleep is similar to human sleep in other ways. Dogs probably have nightmares, just as humans do, Cohen said. They can also get narcolepsy, a disorder that causes the brain to fall into sudden sleep. In fact, research into a line of narcoleptic dogs at Stanford University unraveled the biochemistry behind the human form of the condition.

But dogs probably escape one common human sleep problem: sleep paralysis. In this condition, consciousness returns before the brain "switches on" the muscles again, so people awaken but can't move. Sleep paralysis is often the result of sleep deprivation, which is a rare condition for dogs, Coren said.

"You give a dog an opportunity, and he lies down and he closes his eyes," he said.

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Friday, April 15, 2016

A Brief History of Sound in Cinema


Written by Jordan Kushins

Some of the biggest moments in cinematic history hit your ears before they hit your eyes and keep reverberating long after you've left the theater: Those first spine-tingling notes from John Williams' Star Wars Main Title; Booger's no-contest belch in Revenge of the Nerds. But for a film's sound team, it's also capturing and conveying the sonic subtlety in between those memorable moments that makes a film truly memorable.

"It's long been said that you do a great job in sound when no one notices it," says Gary Rydstrom. Rydstrom is a seven-time Oscar winning Sound Designer and Re-Recording Mixer at Skywalker Sound, and has been in the business since his big break as an audio technician on Indiana Jones and the Temple of Doom in 1984. This somewhat elusive mark of success has gotten consistently easier to achieve over the years, thanks to the wild advances in tech that the industry has experienced since the silent films of the early 1900s.



From the beginning of cinema, tons of experimental attempts were made to more completely merge audio and visual entertainment—with nearly 40 different varieties, many one-offs, before the talkies hit the scene. Productions like Don Juan in 1926 featured a score and sound effects but no dialogue—it wasn't until The Jazz Singer spoke to audiences in 1927 that the talking picture revolution truly took hold of Hollywood (and beyond).

The movie was recorded in Vitaphone, a sound-on-disc that involved the painstaking process of recording all audio onto a single phonographic record, then syncing that up in real time with the projection (similar to the classic college dorm experiment where you play Dark Side of the Moon to start at the same time as the third MGM lion's roar at the start of The Wizard of Oz). In the format wars of the 1920s, however, the far more reliable sound-on-film method (or "optical sound") eventually won out and became the industry standard until the digital revolution.

In the interim, however, filmmakers were not only mastering this developing craft, but also pushing technological limits to serve their ever-more-ambitious visions. At the forefront of that charge in the 1970s was George Lucas, in the midst of producing a risky sci-fi space opera called Star. Mono—where sound is emitted from a single channel, or speaker, based in the front of the theater—wasn't going to do this film justice. Lucas teamed up with the sound dudes at Dolby, and together they engineered what would be the first in a line of significant collaborations: Dolby Stereo. For the first time, sound effects were emitted from four channels—and they were booming. It was a near-instantaneous revolution.

From there on out, Dolby staked its claim as the innovators in cinema sound. In 1991, Batman Returns became the first film released in Dolby Digital 5.1, featuring sound coming from left, right, and center in front, plus right and left. It was a major development for the audience, and also the creatives behind the scenes.

"Digital changed everything," says Rydstrom. "When I started we were on big fat pieces of magnetic tape and dubbers that you had to physically cut. Being able to manipulate sounds digitally was a huge learning curve, but it was so exciting that it didn't matter." Digital also revolutionized mixing consoles. "The first movie I did with James Cameron was Terminator 2 [in 1991], and we had no computerized memory. The next one I did for him was Titanic [in 1997], and the difference was profound."

When Toy Story 3 came out in 2010, the Toy Story and Toy Story 2 were scheduled for a strategically timed rerelease, complete with 3D upgrade. Pixar post-production supervisor Paul Cichocki saw the confluence as an opportunity. "So we've already 'plussed' the look on those," he remembers. "The question was: 'What can we do audibly to take it to another level?'" The goal was to make sound more directional and enveloping, and the solution was Dolby Surround 7.1, which situated speakers in the back of the theater, too.

And now, there is Dolby Atmos. With Atmos, sounds don't just stream through channels—they become "objects" that can be choreographed around a space, and placed in particular spots at specific moments to maximize, well—everything. My introduction to this next-level, multi-dimensional aural revelation was when I saw Gravity at Dolby HQ a few years back—a movie I felt in my guts and bones for at least a week afterwards.

This year, Inside Out—another Atmos creation—is nominated for Best Animated Feature Film at the Oscars. Here's an exclusive video of director Pete Docter and Producer Jonas Riviera discussing the challenges of locating the voices in your head, and articulating that to an audience.


"Traditionally Dolby has been a mastering process," says Stuart Bowling, Dolby director of content and creative relations. "With Atmos, we're going beyond just existing as a mastering tool—we've had to create a plug-in to move sound in this environment, and create a new mastering box." These precise manipulations and the growing dynamic range of what we can hear in theaters—and at home, and on the go—are significant. "These developments are always bringing the sound experience for movies closer to how we hear real life," Rydstrom says.

Recreating how we hear in real life for a film, however, is "annoyingly painstaking," Rydstrom says. In order to make it happen, these pros need the technical know-how, but also a sympathetic ear; it's not necessarily that they hear any better than us non-industry folk, it's just that they hear differently.

"I pay more attention to the sounds in my life," he says. "I think I have a hyperawareness of the emotional effect of sound. Something like the squeak of a screen door can have emotional resonance with people."

So how does that movie sound sausage get made?



"On a live action movie, the main job is to get the acting clear, and wonderful, and free of everything around it," Rydstrom says. "So, on Bridge of Spies the goal of the recording on set was to get a clean Tom Hanks—you don't want to lose any of that performance." (Rydstrom, it should be noted, is nominated for a Best Achievement in Sound Mixing Oscar for for his work on that film.) That audio on its own, however, is "almost antiseptic," intentionally devoid of as much ambient or background noise as possible.

Same goes, in many ways, for modern animation—capturing voices is key. "We're recording actors about three years from release," Cichocki says. "And all of our actors are recorded before we animate. This allows for actors to be free and unconstrained—to really perform. We'll record their performance, and that [audio and video] will then go back to the animators so they can add in those personal bits."

This is a near 180-degree flip from the early talkies, when actors were required to practice their craft in almost complete service to the recording tech's limitations and capabilities. According to Motion Picture Sound Engineering, a hardcover compilation of lectures and papers published in 1938, microphones and recording systems were "robots which pick up everything within their range and record it to the best of their ability. In any case the direction of the robot, the provision of a brain for the microphone, devolves upon the sound man."

Nuanced, it was not. This scene from Singin'in the Rain—one of the greatest movies of all time, but also a trenchant look at the logistical challenges Hollywood's transitionary period between silent films and talkies—shows how challenging it was to get a good take.



So, what's next? For every Atmos experience engineered to give you goosebumps—in theaters, at home, even on mobile devices and VR—there's an equally thrilling renaissance happening in the work of crazy ambitious projects by indie auteurs; and they're utilizing a tool you've got in your pocket right now.

Last year, director Sean Baker made headlines with his Sundance debut, Tangerine—the adventures of two transgender sex workers in Los Angeles on Christmas Eve—which was shot entirely on an iPhone 5. This year, Matthew A. Cherry—a former NFL wide-receiver-turned-filmmaker—will premiere his second feature film, 9 Rides, at SXSW; it is billed as the first to be shot entirely on iPhone 6S in 4k.

"There's such a mystique around filmmaking," Cherry says. "I used to think every movie was a multimillion-dollar affair. Traditionally, the equipment was always the hardest part to get because it was so expensive, but these days everyone owns an iPhone. There are apps that allow you to use your iPhone like a mic pack."

This democratization of technology, as well as any number of ubiquitous online platforms to share work with the world, is giving those without the backing, financial or otherwise, to see their own visions realized.

"Lots of the time you have to figure it out yourself," says Cherry. "But for every movie like a Tangerine, like our film, I think more and more people will start picking it up."

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