A plastic gun made on a 3D printer has been successfully fired. What's more, its developer has released the blueprints online, meaning anyone with the right 3D printer can create a gun of their own, right in their living room. Say hello to the dark side of the maker movement.

This past weekend (May 4), the controversial group Defense Distributed successfully tested the new firearm at a firing range south of Austin, Texas. Called the "Liberator", it took a year to develop. In response, anti-gun campaigners have condemned the project, while a number of law enforcement agencies have started to monitor developments.

The Defense Distributed video notes that the pistol can be "downloaded today." As of this posting, the CAD files for the firearm's 15 printable components are freely available for download on DEFCAD, the 3D-blueprint repository for "misfit objects" operated by Defense Distributed. The Liberator's download link calls up a .ZIP folder containing .STL files for the gun's various components. 3D-printing expert Joseph Flaherty tells io9 that ".STL files can be used by any 3-D printer," after being converted into 3D-printer-friendly file formats – like .GCODE – by any number of freely available software packages, known as "slicers." Translation: with the right equipment, you can download and print a 100% operational handgun. Today.

Defense Distributed says it's aiming to "defend the civil liberty of popular access to arms" through "information and knowledge related to the 3D printing of arms." The company is headed by Cody Wilson, a 25-year-old law student at the University of Texas who describes himself as a "crypto-anarchist." For Wilson, the issue is "about liberty."

Image: BBC.

The BBC recently spoke to him:

"There is a demand of guns - there just is. There are states all over the world that say you can't own firearms - and that's not true anymore.

"I'm seeing a world where technology says you can pretty much be able to have whatever you want. It's not up to the political players any more."

Asked if he felt any sense of responsibility about whose hands the gun might fall into, he told the BBC: "I recognise the tool might be used to harm other people - that's what the tool is - it's a gun.

"But I don't think that's a reason to not do it - or a reason not to put it out there."

Nearly all the parts of the Liberator can be made with a 3D printer, except for the metal firing pin which is made from a single nail. In order for the gun to comply with U.S. law, it must be embedded with a 175 g piece of steel so that it can be picked up by metal detectors.

Writing in the Guardian, Alex Hearn says we probably shouldn't overreact:

But technologically, it's still simple. That's because the principle behind a gun isn't too tricky: load a bullet into a reinforced tube, and whack the back of it hard. That's an engineering problem street gangs in the 1950s managed to solve with wood, antenna housings and elastic bands, building "zip guns" to shoot at each other; and it's also the basis for converted air rifles and cap guns. The difficult stuff – getting it to fire accurately, repeatedly and without jamming or blowing up in your face – is still a long way off for 3D printers. And even the best 3D-printed gun still relies on someone else to make the gunpowder.

The fuss around the printing of guns shows the real impact 3D printing will have on our daily lives. By expanding the realm of "digital" goods into the physical world, it extends the questions we've been struggling with when it comes to the internet – how to control the instructions for hacking copy-protection, encrypting files or making bombs (those last instructions apparently followed by the Tsarnaev brothers in Boston to lethal effect) – to a whole new area...

...Ultimately, trying to pin down whether 3D printing is good or bad is like trying to answer the same question for the internet, telephones or the postal service. Some livelihoods will be transformed, others ruined; the only constant will be the change it bring.

Additional reporting by Robert Gonzalez

My fear exactly.

Researchers in China have created a batch of designer viruses by selectively combining genes from the H5N1 bird flu virus with those of the H1N1 swine flu strain. This reassortment process — which can happen naturally in nature — resulted in several hybridized strains that were able spread through the air and infect mammals.

There is no evidence that H5N1 and H1N1 have ever mixed-and-matched genes on their own, but Chinese scientists are trying to get a leg up on the possibility. It's a similar strategy to the one employed by U.S. and Dutch researchers who deliberately modified the H5N1 virus into a human-contagious form. The idea is to know the enemy — and develop possible countermeasures — before it strikes. The danger/fear, of course, is that the virus could escape from the lab and wreak havoc in human populations.

It's not known if the new hybridized viruses can infect humans.

Ed Yong reports in Nature News:

[Hualan] Chen’s team mixed and matched seven gene segments from H5N1 and H1N1 in every possible combination, to create 127 reassortant viruses, all with H5N1’s HA gene. Some of these hybrids could spread through the air between guinea pigs in adjacent cages, as long as they carried either or both of two genes from H1N1 called PA and NS. Two further genes from H1N1, NA and M, promoted airborne transmission to a lesser extent, and another, the NP gene, did so in combination with PA...

...It is unclear how the results apply to humans. Guinea pigs have bird-like receptor proteins in their upper airways in addition to mammalian ones, so reassortant viruses might bind in them more easily than they would in humans.

And scientists do not know whether the hybrid viruses are as deadly as the parent H5N1. The hybrids did not kill any of the guinea pigs they spread to, but Chen says that these rodents are not good models for pathogenicity in humans.

There is also a chance that worldwide exposure that already occurred to the pandemic H1N1 strain might actually mitigate the risk of a future pandemic by providing people with some immunity against reassortants with H5N1. In an earlier study, Chen and her colleagues showed that a vaccine made from pandemic H1N1 provided some protection against H5N1 infections in mice

Chen's paper has been published in Science. And be sure to read Yong's entire report.

It's called The Periodic Table of Middle-Earth and it was put together by Emil Johansson — a devoted Tolkien fan and an aspiring chemical engineer. Which this awesome chart makes blazingly obvious.

As you can see, Johansson has replaced the standard chemical elements with characters from Lord of the Rings and The Hobbit.

Each character is organized according to race (including Gothmog, who belongs to no known race) and is given a unique symbol and number. Johansson has even added birth and death dates — and a special symbol to denote wearers of the ring.

Here's the entire chart in all its splendour:

Image via from the LOTRproject. H/t Geekosystem.

Very cool.

Ever wonder what it would be like to have your head chopped off? Well, you may soon get the chance to find out. A group of independent developers has created a guillotine simulator using the Oculus Rift virtual reality headset.

During the experience, you can look behind yourself to see the blade coming down, followed by your POV trip to the bottom of a head-catching basket. The simulation can be enhanced by having someone chop their hand down on the back of your neck as is happens. Such fun.

The program, called Disunion, was made during the recent Exile Game Jam by Erkki Trummal, André Berlemont, and Morten Brunbjerg. It's unlikely that the simulator will become anything serious; the developers were probably just experimenting with the possibilities.

Via Disunion.

Related:

• Here's the Real Reason Why Virtual Reality Doesn't Work Yet
• Watch a gamer combine a VR headset with an omnidirectional treadmill
• 90-Year-Old Woman Tries Out Oculus Rift VR Headset, Is Adorable
• Oculus Rift VR headset to be used in Sinful Robots 'erotic encounters'

For nearly a hundred years, Earth has sent radio signals into space. If anyone nearby is listening, they probably know we’re here. In light of this, a new paper assesses the potential danger presented by such signals, concluding that the benefits outweigh the risks. But how can we really know?

Top image: Scene from Battleship (2012), a film in which an alien civilization discovers Earth by detecting its radio emissions.

Leaky Earth?

We’ve been shouting out into the cosmos for quite some time now. Electromagnetic waves of various intensities and frequencies have been streaming away from Earth for well over a century, the remnants of TV broadcasts, mobile phone conversations, satellite transmissions, and military, civil and astronomical radars.

We’ve even deliberately tried to get ET’s attention — a controversial practice known as METI (Messaging to Extraterrestrial Intelligences). There have been many such attempts, including the 2001 Teen-Age Message to the Stars organized by the Russian cosmologist Alexander Zaitsev. His work, and those of others, have been criticized as being insanely risky given the dearth of information we have about the nature of ETIs. Two years ago, John Billingham and James Benford called for a global moratorium on METI, an initiative similar to the one David Brin and myself worked on last decade.

But now, owing to all this human activity, the Earth has a radiosphere that’s inexorably billowing outwards at the speed of light — a clear signal that’s just waiting to be picked up.

And indeed, according to the new paper’s authors, Jacob Haqq-Misra, Michael Busch, Sanjoy Som, and Seth Baum, this leakage could in fact be detected by an extraterrestrial intelligence (ETI) armed with the right listening equipment.

Our signals decrease in intensity as they leak out into the cosmos. But depending on the signal’s strength and frequency, these waves can propagate for cosmologically vast distances and still carry enough information to connote the presence of intelligent life.

Arecibo Observatory. Credit: H. Schweiker/WIYN and NOAO/AURA/NSF.

The Arecibo Planetary Radar in Puerto Rico provides a good example. As the researchers note, at a transmitting power of 0.8 MW and a frequency of 2,380 MHz, the APR’s powerful signal could be picked up by a “watcher” with a 1 km² receiving antenna at distances of up to 200,000 light years!

Credit: Haqq-Misra et al.

That's a rather extraordinary claim, so I spoke to SETI expert and scifi novelist David Brin about it — and he's not convinced detection is this easy. He tole me that, even if an ETI had a one square kilometer array, they would have to point it a at Earth for the duration of an entire year. "Because it would take that long," he told io9. "But why stare if you don't already have a reason to suspect?"

Like SETI Institute's Seth Shostak, Brin believes that Earth is not detectable beyond five light years.

"With one exception: Narrow-focused, coherent (laser-like) planetary radars that are aimed to briefly scan the surfaces of asteroids and moons," he says, "And not to be confused with military radars that disperse."

This new paper, says Brin, is very unconvincing about detectability of leakage.

To transmit or not to transmit?

Earth's leakiness aside, we also need to know if anyone out there is even listening.

As the authors note, some SETI experts contend that, if an ETI really wanted to know that we’re here, they could locate us without having to listen for our radio waves. For example, they could figure out that life is here by analyzing the spectrum of reflected ultraviolet, optical, and near-infrared sunlight from the Earth’s surface and atmosphere. Or, an ETI could learn of our technological civilization by detecting artificial nighttime lighting of large urban areas, or by detecting exaggerated amounts of carbon dioxide in the atmosphere.

More conceptually, advanced civs could could pepper the galaxy with Bracewell communication probes — a point the authors fail to mention in the paper; they could already be in the neighbourhood waiting for a particular signal.

There’s always the possibility, of course, that we’re too far away from the nearest ETI. Or that alien life is rare. Depending on how one fills in the Drake Equation, there could be anywhere from one (just us) to 100,000 — or even millions — of civs currently residing in the galaxy. But we just don’t know, so we don’t really have a good way of knowing how detectable we really are.

Furthermore, and as Brin pointed out to me, the authors failed to address the possibility of colonization. "If travel happens, then the number of sites skyrockets," he says.

Also, ETIs may be able to detect our signals, but they may not be able to make any sense of them — but this is unlikely. If an alien receives a METI signal, it would likely consist of easily decipherable mathematical concepts built upon a computational language (a la Carl Sagan’s Contact). Radio leakage, on the other hand, would be meaningless and almost completely devoid of context. But as the authors write:

Earth’s radio leakage and deliberate transmissions will likely be identifiable by ETI as a technological signature because no other examples of such signals exist in nature. The ability of ETI to decipher or interpret the content of a signal is therefore irrelevant to their ability to use it to learn that humans exist...

But assuming detection is not easy, and that there are other variables at play (like cosmologically vast distances and the potential for many short-lived civilizations), we still need to ask whether or not humanity would benefit or face terrible consequences from alien contact.

To transmit or not to transmit

And indeed, as the authors note, a standard risk assessment is in fact warranted: We should evaluate the probability of an event occurring by multiplying the magnitude of the harm from that event if it does occur.

Sure — sounds sensible. But it’s difficult, if not impossible, to assess the magnitude of the harms that could come from ETI contact. We don’t know the nature of the interactions, nor do we know alien ethics (particularly from a super-technological machine-based civilization).

We also don’t know how we’d interact. The entire relationship could be conducted via remote messaging. But they could send us something rather nasty. At the same time, a positive, non-malicious message could really benefit us. An ETI could provide information about itself or its technologies which could advance and greatly influence the human condition.

Alien contact could also have positive and negative outcomes for many societal structures, religions, and philosophies; different human groups would be affected differently. Interstellar civilizational encounters could be similar to — if not considerably worse than — Europeans who made first contact with stone age societies.

There is another possibility — that the vast majority of our transmissions, and those of a civilization for that matter, will be detected long after we’re gone. Consequently, this is all a futile exercise. If the galaxy is littered with short-lived civilizations — a possible reconciliation of the annoying Fermi Paradox — all radio-transmitting ETIs are essentially sending “time capsule” messages or trace-signatures into space. The galaxy could be awash with echos from extinct civilizations. Determining civilizational longevity, therefore, is crucial to our assessment of the risks and benefits of transmitting into space.

Which brings up another interesting point: Maybe there’s value in transmitting a comprehensive “time-capsule” into space as a way of archiving or preserving our civilization’s vast history. If we go extinct, at least some other civilization may learn about us. Or more romantically, we’ll rest knowing that our signals are propagating through space long after we’re gone.

So, in response to the question of whether or not we should transmit, the authors write:

[B]ecause we cannot estimate the probability or magnitude of contact with ETI, we make no attempt to calculate the term. By extension, any conclusions that depend on knowing are conditional.

Which seems like a rather wishy-washy answer. The authors conclude that “the benefits of radio communication on Earth today outweigh any benefits or harms that could arise from contact with ETI.” What they mean is that it may be more important to our security and survival if we continue to develop powerful communications technologies; it’s simply too valuable (and disruptive) to give up.

But how can they possibly know for sure!? Brin referred to it as "arm-waving mumbo jumbo" — and an "utterly tendentious and unsupported claim."

In regards to METI, the authors conclude that current efforts, which are weak and mostly symbolic, are mostly harmless:

These transmissions create benefits such as opportunities for educational public outreach and the ability to develop scientific groundwork for future METI projects. The costs associated with METI at low levels of detectability are small, so such projects create overall positive value for humanity and should continue.

But ramping up the METI project, like creating powerful beacons, could result in highly uncertain outcomes. Mercifully, the authors conclude that governments and other agencies need to get their act together and start talking about it.

“Even if we never succeed in receiving a message from an extraterrestrial civilization, METI may still prove a worthwhile investment as a way to increase humanity’s awareness of itself in the greater cosmos.”

Unless, of course, someone is in fact listening, and they'd like to pay us a visit...

Read the entire study at Space Policy: “The Benefits and Harms of Transmitting Into Space.”

While it looks like an unprovoked attack by zombie penguins, these are actually Falkland Gentoo penguins returning home through a sandstorm. The photograph was taken by Michael Lohmann — and it has won him the runner-up prize in the bird category of the GDT Nature Photographer of the Year 2013 prize.

Image: Michael Lohmann/GDT.

The penguins, who live on the Falkland's Sea Lion Island, were scurrying home after a long day of feeding at sea. Lohmann was waiting for them on the beach when he snapped the pic.

Here's the entire, uncropped image: "Returning From the Hunt":

More about this fantastic image at New Scientist.

Before even releasing its first flying car, Terrafugia has already begun work on its successor, the TF-X — a much sexier four-seat hybrid capable of vertical takeoff. The company also announced that the Transition will be ready in about two years. Or maybe three. We're so totally holding our breath.

It’s actually been quite a while since we last reported on Terrafugia’s Transition. It’s not the most exciting design, but it can travel 450 miles (725 km) at a speed of 115 mph (185 kph) on regular unleaded gas. On land, and with the wings folded up, it can toddle around at 65 mph (105 kph). Retail will be just shy of $200,000, and will supposedly require only 20 hours of flying lessons.

On Monday May 6, the Woburn, Massachusetts company announced its plans to deliver the Transition flying car to customers by 2015. Or 2016 — a delay of about five years. And we're sure they really, really mean it this time.

Terrafugia also took the time to announce it’s new project, the TF-X. It’ll carry four people (unlike Transition’s two), have a flight range of at least 500 miles (800 km), fly over 200 mph (320 kph), and fit into a standard single car garage. It’ll also be capable of vertical takeoff and landing from a level clearing of at least 100 feet in diameter.

The TF-X will be “safer” and more “convenient,” driven primarily by computer controls. Pilots will be able to steer the vehicle using fly-by-wire controls. More here.

Development is expected to take about 8 to 12 years, so don’t expect it for a while.

Which, as far as flying cars go, isn’t really saying anything new.

Image: Terrafugia.

Paleontologists from Canada have unveiled a newly identified species of a dog-sized pachycephalosaurs. It’s considered the oldest of its kind ever discovered in North America — and quite possibly the world.

Called Acrotholus audeti, the two-legged herbivore roamed the plains of southern Alberta about 85 million years ago. The name is derived from the Greek words for "high dome."

It stood no higher than an adult human’s knee and weighed about 90 lbs (40 kg). Like other pachycephalosaurs, it probably used its dome-shaped skull to head-butt other dinosaurs. Audeti’s skull was composed of solid bone over 4 inches (10 cm) thick.

The discovery was made by David Evans of the Royal Ontario Museum and University of Toronto. He said he was stunned to find a completely intact specimen.

"The species representation of small animals is generally poorer than large animals because the bones of small ones are more susceptible to carnivores and weathering processes," he told CTV News. "The bones of small animals tend to get destroyed before they enter the fossil record."

Evans’s discovery expands our knowledge of pachycephalosaur evolution and their potential diversity. Not much is known about these small dinosaurs, as their fossils are quite rare. But after studying all 600 specimens discovered to date, Evans concluded there were at least 16 varieties of pachycephalosaurs — an indication that these dinosaurs were more diverse and complex than previously thought.

And now, owing to the new discovery, paleontologists are hopeful to find more.

Read more at the journal Nature Communications: “The oldest North American pachycephalosaurid and the hidden diversity of small-bodied ornithischian dinosaurs.”

Image: © Julius T. Csotonyi.

By studying a glob of 20 million-year-old amber, scientists have proven once and for all that glass does not flow.

Some people claim that stained glass windows in old churches are thicker at the bottom than at the top because glass flows slowly like a liquid. We’ve known this isn’t true for quite some time now; these windows are thicker at the bottom owing to the production process. Back during medieval times, a lump of molten glass was rolled, expanded, and flattened before being spun into a disc and cut into panes. These sheets were thicker around the edges and installed such that the heavier side was at the bottom.

But the myth that glass flows has persisted over time. Part of the reason is that glass is a supercooled viscous substance that was vitrified — a massive change in physical properties in which a first-order phase transition was avoided (unlike the standard solid/liquid/gas state of matter transitions).

As a liquid cools, it crystallizes, which increases its viscosity (a measure of its resistance to flow). But when glass cools, it remains stuck in a solid-like state with no crystallization. Essentially, the viscosity of supercooled liquid rises until it becomes an amorphous solid or glass.

Research scientist Robert Brill explains more:

As is the case with liquids, the atoms making up a glass are not arranged in any regular order — and that is where the analogy arises. Liquids flow because there are no strong forces holding their molecules together. Their molecules can move freely past one another, so that liquids can be poured, splashed around, and spilled. But, unlike the molecules in conventional liquids, the atoms in glasses are all held together tightly by strong chemical bonds. It is as if the glass were one giant molecule. This makes glasses rigid so they cannot flow at room temperatures. Thus, the analogy fails in the case of fluidity and flow.

So glass, in this funky state of neither being a solid or liquid, has led some to assume that it’s still potentially in a state of flow.

To finally put this idea to rest, Jing Zhao, Sindee Simon, and Gregory McKenna analyzed a 20 million-year-old chunk of preserved amber. They used amber — an organic polymer — because the dynamics of glass persists regardless of whether it’s organic or inorganic. Fossil amber also offers the opportunity for scientists to study glass-forming materials far below typical glass transition temperatures; given its extreme age, it's an ultra-stable form of glass.

Credit: Texas Tech University.

The team performed a series of calorimetric and stress relaxation experiments on the Dominican amber. They measured its relaxation times (intermolecular rearrangements) at various temperatures, including above its fictive temperature. The team observed that the amber relaxation times did not diverge — meaning that it couldn’t possibly be a kind of fluid.

"This result challenges all the classic theories of glass transition behavior," noted McKenna through a statement.

Read the entire study at Nature Communications: “Using 20-million-year-old amber to test the super-Arrhenius behaviour of glass-forming systems.”

Top image: Vladimir Sazonov/Shutterstock.

Given how slowly our brains react to incoming visual information, it should actually be impossible for us to hit a blistering fastball. But we can. That's because, instead of showing us the world as it really is, our brains offer us a glimpse of the future.

Indeed, our innate ability to track fast-moving objects has perplexed neuroscientists for some time now. But as a new study published today (May 8) in Neuron suggests, our brains “push” forward moving objects such that we perceive them as being further ahead in time and space than they really are. Without even knowing it, we're doing a bit of time traveling.

Tracking moving objects

It takes one-tenth of a second for your brain to process what it sees. Now, that might seem like a really short amount of time, but if an object is coming towards you at 120 mph, like a ball from a tennis serve, it will have travelled 15 feet before your brain knows what hit it — perhaps quite literally.

No doubt — if our brains weren’t able to compensate for these perceptual and motor delays, we’d be in all sorts of trouble. Not only would we have problems hitting a fastball or returning a serve, we wouldn’t be able to pick up on the trajectories of fast-moving objects like cars or incoming fists. We’d also have problems moving objects around, or even navigating our bodies at high speeds.

Neuroscientists have offered some possible solutions, like retinotopic mapping, spatiotopic perceptual maps, or combinations of the two. But these theories don’t do a good job explaining how our brains track objects at fine spatial scales, like the changing positions of fast-moving objects.

Prediction mechanism

To figure out what’s going on, Gerrit Maus from UC Berkeley and his colleagues put six volunteers into a functional Magnetic Resonance Imaging (fMRI) scanner. While their brains were scanned, they watched the “flash-drag effect” (see video) — a two-part visual illusion in which brief flashes can be seen in the direction of motion. The illusion makes people see the flashes as part of the moving background, which in turn triggers the prediction mechanism required to compensate for the brain's processing delays.

After looking at the scans, the researchers were able to pinpoint the part of the visual cortex responsible, a region known as V5. This part of the brain, also called MT+, plays a major role in the perception of motion. And as the researchers now know, V5 also performs calculations about where an object is likely to end up.

"The image that hits the eye and then is processed by the brain is not in sync with the real world, but the brain is clever enough to compensate for that," Maus said in a statement. "What we perceive doesn't necessarily have that much to do with the real world, but it is what we need to know to interact with the real world."

Read the entire article in Neuron: “Motion-Dependent Representation of Space in Area MT+.”

Aspen Photo / Shutterstock.com

Researchers at Japan's Tokyo Institute of Technology have updated their SOINN machine learning algorithm so that it can now use the Internet to identify items it's never encountered before.

SOINN has been in development for some time now. A few years ago, lead researcher Osamu Hasegawa and his team built a robot that can learn, think, and act by itself. But the new iteration of SOINN has a resource that its predecessor did not: The World Wide Web.

As Diginfo reports, SOINN can now scan objects placed in front of it, like a key, knife or pen. Once given an initial keyword to identify it, the system uses that info to scour an online image repository as it seeks out comparable structures.

After its learning session, SOINN is able to recognize any version of the object it encounters.

This might not sound like much, but it blows away standard facial recognition technology. Hasegawa explains:

With previous methods, for example, face recognition by digital cameras, it's necessary to teach the system quite a lot of things about faces. When subjects become diverse, it's very difficult for people to tell the system what sort of characteristics they have, and how many features are sufficient to recognize things. SOINN can pick those features out for itself. It doesn't need models, which is a very big advantage.

Subsequently, SOINN can tell the difference between a box cutter and a knife, or a rickshaw and a car. It's limited to identifying objects in images, but future versions will be able to scan and match content in video and audio.

Image: Tokyo Institute of Technology.

It's not every day you have to give way to a car that lacks a human driver.

This picture was taken in the Berkeley area and posted to Reddit by user ilovepixar. Given that Google has at least 10 self-driving cars in its fleet, this may be a typical sight for people living in the Silicon Valley area. But for the rest of us, this is pretty damned cool — and a startling reminder that the era of the driverless car is all but upon us.

These cars need to soak up a tremendous amount of data in order to work — about 750 megabytes per second. According to Idealab founder and CEO Bill Gross, it captures everything it sees while it's moving, including cars, trucks, birds, rolling balls, and dropped cigarette butts.

Here's what the car "sees" while it makes a left turn:

Gross writes:

If it sees a cigarette butt, it knows a person might be creeping out from between cars. If it sees a rolling ball it knows a child might run out from a driveway. I am truly stunned by how impressive an achievement this is.

I believe that this is an UNDER-hyped revolution in the making.

As of August 2012, Google's driverless vehicles have logged more than 300,000 miles — and all without recording a single accident. Oh, except that time it was crashed by a human driver.

Image via Bill Gross.

Last week we told you about the surprising conclusion reached by a Stanford University professor suggesting that the remains of the alien-like Atacama skeleton belonged to a human between the ages of 6 to 8 — an assertion that seemed impossible to believe given its size. And indeed, a simpler explanation may finally put the mystery to rest.

The preliminary examination was performed by Garry Nolan, professor of microbiology and immunology at Stanford School of Medicine. In addition to concluding that the specimen belonged to a young human child, Nolan suggested that its other deformations, like the elongated head and two missing ribs, were on account of a birth detect.

But according to Paolo Viscardo, a natural history curator at the Horiman Museum in London, there’s no way this skeleton could have come from a child between 6 and 8.

“This seems quite remarkable to me, since I’ve dealt with skeletal foetus specimens rather similar to this in museum collections,” he wrote at his blog, Zygoma.

Rather, the Atacama specimen was probably an aborted 14-16 week fetus that was unceremoniously dumped in the desert, where it underwent a natural mummification process. Viscardo writes:

The main differences I can discern by looking at the high quality photos, X-rays and CT scan...are that the Atacama specimen is from a slightly earlier stage foetus...it has mummified soft tissue that has shrunk tight...pulling the ribcage into a more narrow configuration; and the head has been distorted, probably as a result of an illegal back-street abortion where a hook has been used to extract the foetus...causing damage to the back of the skull and stretching the pliable head.

Viscardo admits that the hole in the head may have occurred during the scientists' examinations, which would be consistent with other images showing a skull without a hole.

Viscardo’s fetus hypothesis would also explain not just the small size, but why there are only 10 pairs of ribs; the lower ‘floating ribs’ were still under development and had not yet fully formed.

“It would also explain why there is no evidence in the x-rays of the deciduous or unerupted permanent dentition that you would expect to find in a 6-8 year old,” he writes.

Viscardo also argues that the age estimate was overly influenced by the high density of the bone in the x-rays of the specimen, which is typical of mummified specimens.

Read more at Zygoma, including Viscardo’s remarks about Chile’s restrictive abortion laws.

H/t to io9 reader ParticleNoun!

Images: Atacama Humanoid © 2013 Sirius Disclosure.

A human driver + a Google engineer in the passenger seat.

A new study suggests that Mars’s 3.5-mile high Mount Sharp formed as strong winds carried dust and sand into the crater in which it rests. If true, Gale Crater probably never contained a lake, which would totally suck, because that’s one of the main reasons why NASA sent Curiosity there in the first place.

Gale Crater is about 96 miles (154 km) in diameter and is estimated to be about 3.5 to 3.8 billion years old. It has a really unique feature — an enormous mound of sedimentary debris extending to a height equivalent to that of Alaska’s Mt. McKinley. Formally, it’s known as Aeolis Mons, but everyone just calls it Mount Sharp.

The going theory about its formation, which has now been put in serious doubt owing to the new study, is that it is the eroded remnant of sedimentary layers that once filled the crater — layers of silt that were originally deposited on a massive lakebed.

Consequently, the area may have once featured vast reservoirs of water. NASA scientists figured that Mt. Sharp would be a fantastic geological structure for Curiosity to study — especially as far as Martian habitability is concerned.

But if the new research is correct, the mound will yield no such clues.

A SWEET Hypothesis

According to researchers based at Princeton University and the California Institute of Technology, Mt. Sharp likely emerged as strong winds carried dust and sand into the hole over the course of millions of years — a process driven by a wind feedback effect. The researchers, a team consisting of Edwin Kite, Kevin Lewis, and other, are calling it the slope wind enhanced erosion and transport (SWEET) hypothesis.

During the day, air rises from the crater as the surface is pounded by sunlight. But then, when things cool down at night, it sweeps back down its steep walls. These slope winds, or katabatic winds, would have been strong along the crater’s walls, but weak at the crater’s center, which is where the debris would have slowly accumulated.

Image: Air would have flowed up the crater rim (red arrows) and the flanks of Mt. Sharp (yellow) in the morning when the surface warmed, and reversed in the cooler late afternoon. Blue indicates the more variable wind patterns on the crater floor, the X marks Curiosity's landing site.

What’s more, previous theories about the mound’s formation don’t add up. There’s no way, say the researchers, that previously proposed processes could have resulted in sedimentary strata that outwardly dips the way it does from the mound’s center.

Image: The various layers of sediment that make up the mound did not extend to the crater wall and also display a consistent tilt, or "dip," away from the center of the mound. The yellow star shows Curiosity's initial location.

Not a Total Loss — and Not By a Longshot

NASA chose the Gale Crater site for a number of reasons, and not merely because it may have been the site of an ancient lake. Indeed, back in December Curiosity found traces of clay, water molecules and even organic compounds. To suggest that landing in Gale Crater was a complete mistake would be totally unfair.

Moreover, as the researchers themselves admit, a body of water could have existed in the moat surrounding the base of Mt. Sharp. And even if the bulk of the material was deposited by wind, the area will continue to produce valuable information about the region’s geological, and possibly biological, past.

But if the new SWEET hypothesis is true, Gale Crater could ultimately prove to be less than ideal. As the authors write in the paper, the region has limited organic carbon preservation potential.

"The quest to determine whether Mars could have at one time supported life might be better directed elsewhere,” noted study co-author Kevin Lewis through a statement.

Read the entire study at Geology: "Growth and form of the mound in Gale Crater, Mars: Slope wind enhanced erosion and transport.”

Photo of Curiosity via NASA; inset images via Kevin Lewis.

As anyone with a dog whistle knows, the range of human hearing is hardly anything to get excited about. But when it comes to picking up extremely high frequencies, there’s one particular creature that even dogs can’t compete with.

The animal is the greater wax moth, Galleria mellonella. And get this — it can hear frequencies as high as 300 kHz!

For contrast, humans max out at 20 kHz, and dogs at 40 kHz. The harbour porpoise can hear frequencies up to 110 kHz, while bottlenose dolphins can pick up sounds as high as 150 kHz (which they use for echolocation). Even other moths, like some located in North America, can “only” hear up to 150 kHz.

Oh, and there is another animal to consider: The bat. Their echolocation calls can reach upwards of 212 kHz.

And indeed, it’s because of bats that the greater wax moth can hear so well. These two species are currently engaged in an auditory arms race — and the moth is winning. These moths can tell when they’ve been hit by an echolocation pulse, and they make evasive maneuvers when it happens. This has resulted in increasingly stronger hearing over time; it’s classic Darwinianism at work.

But here’s where Darwin gets a bit unorthodox. As new research from Hannah Moir and colleagues at the University of Strathclyde in Glasgow has shown, Galleria mellonella seems to have evolved a pre-adaptation in response to the bat’s hunting technique.

Which doesn’t make a lot of sense given what we know of selectional processes. But Moir has two theories.

First, it’s possible that bats are producing frequencies that are higher than can be recorded. Microphones tend to flake out when sounds exceed 150 kHz, and bat calls are hard to capture.

Second, the adaptation could be an accident. But that seems unlikely given that evolution doesn’t tend to reinforce “accidental” traits over time when there's a total lack of selective pressures to uphold those genetic characteristics.

Regardless, bats have some evolving to do.

Read the entire study at Biology Letters: “Extremely high frequency sensitivity in a ‘simple’ ear.”

Image: Luis Carlos Torres/Shutterstock. Moth image via.

Sure, this adorable little inchworm robot looks cute. But just wait for the day when more sophisticated versions start printing and assembling themselves from scratch — and all without human oversight.

We've seen self-assembling robots before, but not one that came out of a 3D printer.

This printed inchworm robot was developed by Samuel Felton and colleagues at the School of Engineering and Applied Sciences and the Wyss Institute for Biologically Inspired Engineering at Harvard University and the Computer Science and Artificial Intelligence Laboratory at MIT.

IEET Spectrum explains how it works:

Self-folding happens thanks to shape memory polymers that contract when heated. By printing these polymers on one side of a hinged substrate and then heating them, the hinge can be made to bend. The amount of bend is controlled by etching flexible connectors that connect both sides of the hinge, and with enough hinges heated in the right order, it’s possible to create fairly complex folded shapes, including things like interlocking structural elements.

The tricky part of the process is the folding of the robot itself: installing the battery and motor is trivial enough for a human to do, which means that a relatively simple pick and place robot should have no problems doing the same thing. This means that these robots have the potential to scale massively: they can be printed out of cheap materials, they fold themselves together, and another robot can plonk some hardware on them and they’re good to go.

"Robot Self-Assembly by Folding: A Printed Inchworm Robot," was presented this week at 2013 IEEE International Conference on Robotics and Automation (ICRA) 2013 in Germany.

Fixed, sorry for the error.