The design of a new life-size bot named Kengoro closely resembles the anatomy of a teenage boy in body proportion, skeletal and muscular structure, and joint flexibility, researchers report online December 20 in Science Robotics. Compared with previous humanoid robots with more rigid, bulky bodies, Kengoro’s anatomically inspired design gives the bot a wide range of motion to perform humanlike, full-body exercises. Constructed by Masayuki Inaba, an engineer at the University of Tokyo, and colleagues, Kengoro has a multi-jointed spine that allows the robot to curl into a sit-up or do back extensions. The bot’s arms are limber enough to execute various stretches or swing a badminton racket. And its artificial muscles are strong enough that Kengoro can stand on tiptoe or do push-ups. Batteries in each leg power Kengoro through about 20 minutes of exercise at a time, and water seeping from inside Kengoro’s metal skeleton like sweat keeps the motors of the artificial muscles cool while the bot works out.
Such a nimble robot that so closely imitates human movement and anatomy is “very unique,” says Luis Sentis, an engineer at the University of Texas at Austin not involved in the work. Building more humanlike robots could lead to the development of more sophisticated prosthetics or more realistic crash-test dummies that make humanlike reflexive movements during an accident.
Improvisation may give jazz artists a creative boost not seen among musicians more likely to stick to the score. Jazz musicians’ brains quickly embrace improvisational surprises, new research on the neural roots of creativity shows.
Neuroscientist Emily Przysinda and colleagues at Wesleyan University in Middletown, Conn., measured the creative aptitudes of 12 jazz improvisers, 12 classical musicians and 12 nonmusicians. The researchers first posed creativity challenges to the volunteers, such as listing every possible use for a paper clip. Volunteers then listened to three different kinds of chord progressions — common ones, some that were a bit off and some that went in wild directions — as the team recorded the subjects’ brain waves with an electroencephalogram. Afterward, volunteers rated how much they liked each progression.
Jazz musicians, more so than the other participants, preferred the unexpected riffs, brain waves confirmed. And the improvisers’ faster and stronger neural responses showed that they were more attuned to unusual music and quickly engaged with it. Classical musicians’ and nonmusicians’ brains hadn’t yet figured out the surprising music by the time the jazz musicians had moved on, the researchers report in the December Brain and Cognition.
The jazz musicians’ striking responses to unexpected chords mirrored their out-of-the-box thinking on the creativity challenges. Training to be receptive to the unexpected in a specific area of expertise can increase creativity in general, says Harvard University cognitive neuroscientist Roger Beaty, who was not involved in the study.
Despite a reputation as mellow apes, bonobos have a thing for bad guys.
Rather than latching on to individuals with a track record of helpfulness, adult bonobos favor obstructionists who keep others from getting what they want. The result may help explain what differentiates humans’ cooperative skills from those of other apes, biological anthropologists Christopher Krupenye of the University of St. Andrews in Scotland and Brian Hare of Duke University report online January 4 in Current Biology. Previous investigations indicate that, by 3 months old, humans do the opposite of bonobos, choosing to align more frequently with helpers than hinderers. Humans, unlike other apes, have evolved to seek cooperative partnerships that make large-scale collaborations possible (SN: 10/28/17, p. 7), Krupenye and Hare propose.
“Conducting similar experiments with chimpanzees and other apes is a key next step,” Krupenye says. If chimps view hinderers as kindly as bonobos do, that finding would support the duo’s proposal about human cooperation, he says.
Bonobos may view those who impede others’ actions as socially dominant and thus worth grooming as allies, Krupenye says. Although bonobos readily share food, social pecking orders still affect the animals’ behavior.
The researchers showed 24 bonobos four animated videos featuring pairs of colored shapes, most depicted with a pair of eyes. In one video, a circle tries and fails to climb a hill until a “helper” triangle arrives and pushes the circle to the top. In a second video, a circle tries and fails to climb a hill before a “hinderer” square arrives and pushes the circle farther down the hill. In the other two videos, other shapes with eyes push an eyeless, unmoving circle up or down a hill. After watching the first two videos, bonobos chose between paper cutouts of helper and hinderer shapes placed on top of small apple pieces. The same choice was presented for cutouts of shapes from the last two videos.
Snacks covered by hinderer shapes were chosen about 70 percent of the time by the 14 adult animals, ages 9 and older. Younger bonobos displayed no strong preference either way. Apes of all ages showed no partiality to either shape that had pushed inanimate circles.
Adult bonobos also reached more often for an apple piece offered by a human they had observed snatch a toy dropped by another person, versus a human they had seen return the toy.
In a final experiment, eight of 24 bonobos usually selected apple pieces covered by cutouts of an animated shape that the apes had seen win a contest with another shape to occupy a location. This result suggests that some bonobos’ strong preference for dominant individuals partly accounts for the newly reported fondness for hinderers, Krupenye says.
“The notion that bonobos approach the bully because they view that individual as more dominant is a very plausible interpretation,” says psychologist Felix Warneken of the University of Michigan in Ann Arbor. Warneken, who did not participate in the new study, studies cooperative behavior in human children and nonhuman apes.
In 1929, the German scientist Ernst Grafenberg inserted silver rings into the uteri of 2,000 women, and reported a pregnancy rate of only 1.6 percent. Despite this history, the use of intrauterine devices, or IUDs, was not generally accepted.… A report made public last week by the FDA’s Advisory Committee on Obstetrics and Gynecology concludes that while it doesn’t know how they work, it finds IUDs to be safe and effective in blocking conception. — Science News, February 3, 1968. Update Early intrauterine devices came in myriad shapes, including a double-S, loops and spirals. One IUD, the spiked Dalkon Shield, was taken off the market in 1974 amid complaints of severe infections. Consumers quickly lost interest. But after companies redesigned the devices in the 1990s, use rose. From 1988 to 2002, just 1.5 percent of U.S. women ages 15 to 44 used an IUD; from 2011 to 2013, use was as high as 7.2 percent.
Scientists now know how IUDs prevent pregnancy. Hormonal IUDs thin the lining of the uterus and thicken the mucus on the cervix, preventing sperm from swimming. The devices can also reduce how frequently women ovulate. Copper IUDs and others without hormones prevent pregnancy by releasing ions that create a sperm- and egg-killing environment in women’s reproductive tracts. IUDs and other long-acting contraceptives are currently the most reliable reversible forms of birth control (SN: 6/30/12, p. 9).
Storms of powdery Martian soil are contributing to the loss of the planet’s remaining water.
This newly proposed mechanism for water loss, reported January 22 in Nature Astronomy, might also hint at how Mars originally became dehydrated. Researchers used over a decade of imaging data taken by NASA’s Mars Reconnaissance Orbiter to investigate the composition of the Red Planet’s frequent dust storms, some of which are vast enough to circle the planet for months.
During one massive dust storm in 2006 and 2007, signs of water vapor were found at unusually high altitudes in the atmosphere, nearly 80 kilometers up. That water vapor rose within “rocket dust storms” — storms with rapid vertical movement — on convection currents similar to those in some storm clouds on Earth, says study coauthor Nicholas Heavens, an astronomer at Hampton University in Virginia. At altitudes above 50 kilometers, ultraviolet light from the sun easily penetrates the Red Planet’s thin atmosphere and breaks down water’s chemical bonds between hydrogen and oxygen. Left to its own devices, hydrogen slips free into space, leaving the planet with less of a vital ingredient for water.
“Because it’s so light, hydrogen is lost relatively easily on Mars,” Heavens says. “Hydrogen loss is measurable from Earth, too, but we have so much water that it’s not a big deal.”
Previous studies have indicated that Mars, which was once covered in an ocean about 100 meters deep, lost the bulk of its water through hydrogen escape (SN Online: 10/15/14). But this is the first study to identify dust storms as a mechanism for helping the gas break away. The total effect of all dust storms could account for about 10 percent of Mars’ current hydrogen loss, Heavens says. Whether that was true in the past is up in the air. Extrapolating back billions of years ago, when Mars was warm and wet, isn’t so easy. Scientists don’t know how dust storms would have worked in a wetter climate or a thicker atmosphere.
“Variations over weeks or months don’t really tell you anything about the 1,000-year timescale that governs hydrogen,” notes Kevin Zahnle, an astronomer at NASA’s Ames Research Center in Moffett Field, Calif., who was not involved in the study.
But Zahnle, an expert on atmospheric escape of gases, agrees with the main thrust of the study: Right now, dust storms are helping to bleed Mars dry.
Maybe Earth’s early years weren’t so hellish after all.
Asteroid strikes repeatedly bombarded the planet during its first eon, but the heat released by those hits wasn’t as sterilizing as once thought, new research suggests. Simulations indicate that after the first few hundred million years of bombardment, the heat from the impacts had dissipated enough that 10 to 75 percent of the top kilometer of the subsurface was habitable for mesophiles — microbes that live in temperatures of 20° to 50° Celsius. If so, the planet may have been habitable much earlier than previously believed. Earth’s earliest eon, the Hadean, spans the period from about 4.6 billion years ago, when the planet was born, to 4 billion years ago. The name, for the Greek god of the underworld, reflects the original conception of the age: dark and hellish and inhospitable to life. But little direct evidence of Hadean asteroid impacts still exists, limiting scientists’ understanding of how those collisions affected the planet’s habitability.
“There has been an assumption that the Hadean was mostly an uninteresting slag heap until the sky stopped falling and life could take hold,” says Stephen Mojzsis, a geologist at the University of Colorado Boulder. That’s not to say that all of the Hadean was pleasant; the first 150 million years of Earth’s history, which included the giant whack that formed the moon, were pretty dramatic. But after that, things settled down considerably, says Mojzsis, who was not an author of the new study.
For example, scientists have found signs of liquid water and even faint hints of possible life in zircon crystals dating back 4.1 billion years (SN: 11/28/15, p. 16). Other researchers have contested the idea that Earth was continually bombarded by asteroids through much of the Hadean, or that a last barrage of asteroids shelled the planet 3.9 billion years ago in what has been called the Late Heavy Bombardment, killing any incipient life (SN Online: 9/12/16).
Story continues below illustration In the new study, geophysicist Robert Grimm and planetary scientist Simone Marchi, both of the Southwest Research Institute in Boulder, Colo., estimated how hot it would have been just a few kilometers beneath the planet’s surface during the Hadean. The scientists used an estimated rate of asteroid bombardment, as well as how much heat the projectiles would have added to the subsurface and how much that heat would have dissipated over time to simulate how hot it got — and whether microbial life could have withstood those conditions. The research built on earlier work, including Marchi’s 2014 finding that asteroid impacts became smaller and less frequent with time (SN: 8/23/14, p. 13).
Asteroid impacts did heat the subsurface, according to the simulations, but even the heaviest bombardment scenarios were not intense enough to sterilize the planet, the researchers report March 1 in Earth and Planetary Science Letters. And if the rate of bombardment did decrease as the eon progressed, the heat the asteroids delivered to Earth’s subsurface would also have had time to dissipate. As a result, that habitable zone would have increased over time.
A Late Heavy Bombardment, if it occurred, would have been tougher for the microbes, because the heat wouldn’t have had time to dissipate with such a rapid barrage. But that just would have meant the habitable zone didn’t increase, the team reports; mesophiles could still have inhabited at least 20 percent of the top kilometer of subsurface.
Mojzsis says he’s come to similar conclusions in his own work. “For a long time people said, with absolutely no data, that there could be no biosphere before 3.9 billion years ago,” he says. But “after the solar system settled down, the biosphere could have started on Earth 4.4 billion years ago.”
That’s not to say that there was definitely life, Grimm notes. Although the heat from impacts may not have been a limiting factor for life, asteroid bombardment introduced numerous other challenges, affecting the climate, surface or even convection of the mantle. Still, the picture of Earth’s earliest days is undergoing a sea change. As Grimm says, “An average day in the Hadean did not spell doom.”
Clumps of dark matter may be sailing through the Milky Way and other galaxies.
Typically thought to form featureless blobs surrounding entire galaxies, dark matter could also collapse into smaller clumps — similar to normal matter condensing into stars and planets — a new study proposes. Thousands of collapsed dark clumps could constitute 10 percent of the Milky Way’s dark matter, researchers from Rutgers University in Piscataway, N.J., report in a paper accepted in Physical Review Letters. Dark matter is necessary to explain the motions of stars in galaxies. Without an extra source of mass, astronomers can’t explain why stars move at the speeds they do. Such observations suggest that a spherical “halo” of invisible, unidentified massive particles surrounds each galaxy.
But the halo might be only part of the story. “We don’t really know what dark matter at smaller scales is doing,” says theoretical physicist Matthew Buckley, who coauthored the study with physicist Anthony DiFranzo. More complex structures might be hiding within the halo.
To collapse, dark matter would need a way to lose energy, slowing particles as gravity pulls them into the center of the clump, so they can glom on to one another rather than zipping right through. In normal matter, this energy loss occurs via electromagnetic interactions. But the most commonly proposed type of dark matter particles, weakly interacting massive particles, or WIMPs, have no such way to lose energy.
Buckley and DiFranzo imagined what might happen if an analogous “dark electromagnetism” allowed dark matter particles to interact and radiate energy. The researchers considered how dark matter would behave if it were like a pared-down version of normal matter, composed of two types of charged particles — a dark proton and a dark electron. Those particles could interact — forming dark atoms, for example — and radiate energy in the form of dark photons, a dark matter analog to particles of light. The researchers found that small clouds of such dark matter could collapse, but larger clouds, the mass of the Milky Way, for example, couldn’t — they have too much energy to get rid of. This finding means that the Milky Way could harbor a vast halo, with a sprinkling of dark matter clumps within. By picking particular masses for the hypothetical particles, the researchers were able to calculate the number and sizes of clumps that could be floating through the Milky Way. Varying the choice of masses led to different levels of clumpiness.
In Buckley and DiFranzo’s scenario, the dark matter can’t squish down to the size of a star. Before the clumps get that small, they reach a point where they can’t lose any more energy. So a single clump might be hundreds of light-years across.
The result, says theoretical astrophysicist Dan Hooper of Fermilab in Batavia, Ill., is “interesting and novel … but it also leaves a lot of open questions.” Without knowing more about dark matter, it’s hard to predict what kind of clumps it might actually form.
Scientists have looked for the gravitational effects of unidentified, star-sized objects, which could be made either of normal matter or dark matter, known as massive compact halo objects, or MACHOs. But such objects turned out to be too rare to make up a significant fraction of dark matter. On the other hand, says Hooper, “what if these things collapse to solar system‒sized objects?” Such larger clumps haven’t have been ruled out yet.
By looking for the effects of unexplained gravitational tugs on stars, scientists may be able to determine whether galaxies are littered with dark matter clumps. “Because we didn’t think these things were a possibility, I don’t think people have looked,” Buckley says. “It was a blind spot.”
Up until now, most scientists have focused on WIMPs. But after decades of searching in sophisticated detectors, there’s no sign of the particles (SN: 11/12/16, p. 14). As a result, says theoretical physicist Hai-Bo Yu of the University of California, Riverside, “there’s a movement in the community.” Scientists are now exploring new ideas for what dark matter might be.
The first 117 elements on the periodic table were relatively normal. Then along came element 118.
Oganesson, named for Russian physicist Yuri Oganessian (SN: 1/21/17, p. 16), is the heaviest element currently on the periodic table, weighing in with a huge atomic mass of about 300. Only a few atoms of the synthetic element have ever been created, each of which survived for less than a millisecond. So to investigate oganesson’s properties, scientists have to rely largely on theoretical predictions. Recent papers by physicists, including one published in the Feb. 2 Physical Review Letters, detail some of the strange predicted properties of the weighty element.
Relatively weird According to calculations using classical physics, oganesson’s electrons should be arranged in shells around the nucleus, similar to those of xenon and radon, two other heavy noble gases. But calculations factoring in Einstein’s special theory of relativity, which take into account the high speeds of electrons in superheavy elements, show how strange the element may be. Instead of residing in discrete shells — as in just about every other element — oganesson’s electrons appear to be a nebulous blob.
Getting a reaction On the periodic table, oganesson is grouped with the noble gases, which tend not to react with other elements. But because of how its electrons are configured, oganesson is the only noble gas that’s happy to both give away its electrons and receive electrons. As a result, the element could be chemically reactive.
Solid as a rock? Oganesson’s electron configuration could also let atoms of the element stick together, instead of just bouncing off one another as gas atoms typically do. At room temperature, scientists expect that these oganesson atoms could clump together in a solid, unlike any other noble gases.
Bubbling up Protons inside an atom’s nucleus repel one another due to their like charges, but typically remain bound together by the strong nuclear force. But the sheer number of oganesson’s protons — 118 — may help the particles overcome this force, creating a bubble with few protons at the nucleus’s center, researchers say. Experimental evidence for a “bubble nucleus” has been found for an unstable form of silicon (SN: 11/26/16, p. 11).
Neutral territory Unlike oganesson’s protons, which are predicted to be in distinct shells in the nucleus, the element’s neutrons are expected to mingle. This is at odds with some other heavy elements, in which the neutron rings are well-defined.
For Oganessian, these theoretical predictions about the element have come as a surprise. “Now it’s up to experiment,” he says. Predictions about the bizarre element could be put to the test once a facility for creating superheavy elements, under construction at Oganessian’s lab in Dubna, Russia, is up and running later this year.
AUSTIN, Texas — If alien microbes crash-land on Earth, they may get a warm welcome.
When people were asked how they would react to the discovery of extraterrestrial microbial life, they give generally positive responses, researchers reported at a news conference February 16 at the annual meeting of the American Association for the Advancement of Science.
This suggests that if microbial life is found on Mars, Saturn’s icy moon Enceladus (SN: 5/13/17, p. 6) or elsewhere in the solar system, “we’ll take the news rather well,” said Michael Varnum, a social psychologist at Arizona State University in Tempe. What’s more, the tone of news reports announcing potential evidence for intelligent aliens suggests people would welcome that news, too. Varnum and colleagues asked about 500 online volunteers — all in the United States — to describe how they would react if they learned scientists had discovered alien microbes. Varnum’s team analyzed each response using software that determined the fraction of words indicating positive emotion, such as “nice,” and negative emotion, like “worried.” The program also scanned for reward- and risk-focused words, such as “benefit” and “danger.” People generally used more positive and reward-oriented words than negative and risk-oriented ones to describe their anticipated reactions. The same held true when participants were asked how they expected everyone else to take the news. In another study, Varnum’s team asked about 500 U.S.-based volunteers to read one of two newspaper articles. One from 1996 reported the discovery of evidence for fossilized Martian microbes in a meteorite (SN: 8/10/96, p. 84). In the second, researchers announced in 2010 that they had created a synthetic bacterial cell in the lab (SN: 6/19/10, p. 5). Both groups responded favorably to the articles, but the people who read about Martian microbes had a more positive reaction. This suggests that while people feel good about discoveries of any previously unknown life-forms, they are particularly keen on finding aliens, Varnum says.
But “any finding that comes from one population — like Americans — you have to take with a grain of salt,” Varnum says. He and his colleagues now hope to gather responses from participants of different cultures, to compare how people across the globe would take the news of alien microbes.
Psychologist and SETI researcher Douglas Vakoch, who heads the nonprofit organization Messaging Extraterrestrial Intelligence in San Francisco, suggests researchers also gauge reactions to different scenarios of alien microbial discovery. The Martian meteorite described in the 1996 article “has been on Earth for a long time and nothing bad has happened,” says Vakoch, who wasn’t involved in the work. “That’s a really safe scenario.” But, he wonders, are people as gung-ho about the prospect of finding live microbes on other planets or aboard meteorites?
And what if the aliens were intelligent? “If you find intelligent life elsewhere, [you] know that you’re not the only kid on the block,” says Seth Shostak, an astronomer at the SETI Institute in Mountain View, Calif. Knowing that human intelligence isn’t so special after all could provoke a much different emotional response than finding mere microbes “like pond scum in space,” Shostak says.
To get a sense of how people would feel about finding intelligent aliens, Varnum analyzed reports that the interstellar asteroid ‘Oumuamua could be an alien spaceship (SN Online: 12/18/17). The news articles took a largely positive angle. So the broader public might also take kindly to the discovery of little green men, Varnum says.
Tap — gently — the plump rear of a young Nessus sphinx hawk moth, and you may hear the closest sound yet discovered to a caterpillar voice.
Caterpillars don’t breathe through their mouths. Yet a Nessus sphinx hawk moth, if disturbed, will emit from its open mouth a sustained hiss followed by a string of scratchy burplike sounds. “Hard to describe,” says animal behaviorist Jayne Yack of Carleton University in Ottawa, who urges people just to listen to it for themselves. This newfound noise from young Amphion floridensis may startle birds or other would-be predators not expecting something as generally quiet as most caterpillars to erupt in sound.
The discovery marks the fourth sound-producing mechanism in caterpillars that Yack and colleagues have found. Some caterpillars use their spiracles, respiratory pores along the flanks, to toot sounds. Caterpillars take in oxygen and release waste carbon dioxide through these pores. These gases, which don’t depend on the caterpillar version of blood to travel throughout the body, move through a branching air duct system of increasingly tiny pipes. Two other kinds of caterpillar noises involve mouthparts rubbing against each other. But none of those noisemakers are involved here, researchers report online February 26 in Journal of Experimental Biology.
Instead, the new anatomical studies and computer modeling suggest that these caterpillars speak by pulling air in through their mouths and into their guts and then releasing it. The rush of air inward could create the first hissing part, and outrushes could make the string of scratchy burps. There’s no sign of a special sound-making flap in the gut, but air whooshing through a constriction could make noisy turbulence. That could give a caterpillar voice its own version of teakettle squeals. In miniature, of course.
