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I’ve been to the playground enough times to know a juicy parenting controversy when I see (or overhear) one. Bed-sharing, breastfeeding and screen time are always hot-button issues. But I’m not talking about any of those. No, I’m talking about actual juice.

Some parents see juice as a delicious way to get vitamins into little kids. Others see juice as a gateway drug to a sugar-crusted, sedentary lifestyle, wrapped up in a kid-friendly box. No matter where you fall on the juice spectrum, you can be sure there are parents to either side of you. (Disclosure: My kids don’t drink much juice, simply because the people who buy their groceries aren’t all that into it. And juice is heavy.)

Scientific studies on the effects of juice have been somewhat sparse, allowing deeply held juice opinions to run free. One of the chief charges against juice is that it’s packed with sugar. An 8-ounce serving of grape juice, even with no sugar added, weighs in at 36 grams. That tops Coca-Cola, which delivers 26 grams of sugar in 8 ounces. And all of those extra sweet calories can lead to extra weight.

A recent review of eight studies on juice and children’s body weight, published online March 23 in Pediatrics, takes a look at this weight concern. It attempts to clarify whether kids who drink 100 percent fruit juice every day are at greater risk of gaining weight. After sifting through the studies’ data, researchers arrived at an answer that will please pro-juicers: Not really.

“Our study did not find evidence that consuming one serving per day of 100 percent fruit juice influenced BMI to a clinically important degree,” says study coauthor Brandon Auerbach of the University of Washington in Seattle.

The analysis found that for children ages 1 to 6, one daily serving of juice (6 to 8 ounces) was associated with a sliver of an increase in body mass index, or BMI. Consider a 5-year-old girl who started out right on the 50th percentile for weight and BMI. After a year of daily juice, this girl’s BMI may have moved from the 50th to the 52nd or 54th percentile, corresponding to a weight increase of 0.18 to 0.33 pounds over the year. That amount “isn’t trivial, but it’s not enough on its own to lead to poor health,” Auerbach says.

The results, of course, aren’t the final word. The analysis was reviewing data from other studies, and those studies came with their own limitations. For one thing, the studies didn’t assign children to receive or not receive juice. Instead, researchers measured the children’s juice-drinking behavior that was already under way and tried to relate that to their weight. That approach means that it’s possible that differences other than juice consumption could influence the results.
It’s important to note the distinction here between the 100 percent fruit juice in the studies and fruit cocktails, which are fruit-flavored drinks that often come with lots of added sugar. The data on those drinks is more damning in terms of weight gain and the risk of cavities, Auerbach says.

Also worth noting: The American Academy of Pediatrics recommends that kids between ages 1 and 6 get only 4 to 6 ounces of juice a day. That’s a smaller amount than many of the kids in the studies received. And the AAP recommends babies younger than 6 months get no juice at all.

In general, whole fruits, such as apples and oranges, are better than juice because they provide fiber and other nutrients absent from juice. (Bonus for toddlers: Oranges are fun to peel. Bummer for parents: Doing so makes a sticky mess.)

Still, the new analysis may ease some guilt around letting the juice flow. And it can enable parents to save their worries for more harmful things, of which there are plenty.

Like 1980s hair bands, male cockatoos woo females with flamboyant tresses and killer drum solos.

Male palm cockatoos (Probosciger aterrimus) in northern Australia refashion sticks and seedpods into tools that the animals use to bang against trees as part of an elaborate visual and auditory display designed to seduce females. These beats aren’t random, but truly rhythmic, researchers report online June 28 in Science Advances. Aside from humans, the birds are the only known animals to craft drumsticks and rock out.
“Palm cockatoos seem to have their own internalized notion of a regular beat, and that has become an important part of the display from males to females,” says Robert Heinsohn, an evolutionary biologist at the Australian National University in Canberra. In addition to drumming, mating displays entail fluffed up head crests, blushing red cheek feathers and vocalizations. A female mates only every two years, so the male engages in such grand gestures to convince her to put her eggs in his hollow tree nest.

Heinsohn and colleagues recorded more than 131 tree-tapping performances from 18 male palm cockatoos in rainforests on the Cape York Peninsula in northern Australia. Each had his own drumming signature. Some tapped faster or slower and added their own flourishes. But the beats were evenly spaced — meaning they constituted a rhythm rather than random noise.

From bonobos to sea lions, other species have shown a propensity for learning and recognizing beats. And chimps drum with their hands and feet, sometimes incorporating trees and stones, but they lack a regular beat.

The closest analogs to cockatoo drummers are human ones, Heinsohn says, though humans typically generate beats as part of a group rather than as soloists. Still, the similarity hints at the universal appeal of a solid beat that may underlie music’s origins.

Quantum particles can burrow through barriers that should be impenetrable — but they don’t do it instantaneously, a new experiment suggests.

The process, known as quantum tunneling, takes place extremely quickly, making it difficult to confirm whether it takes any time at all. Now, in a study of electrons escaping from their atoms, scientists have pinpointed how long the particles take to tunnel out: around 100 attoseconds, or 100 billionths of a billionth of a second, researchers report July 14 in Physical Review Letters.
In quantum tunneling, a particle passes through a barrier despite not having enough energy to cross it. It’s as if someone rolled a ball up a hill but didn’t give it a hard enough push to reach the top, and yet somehow the ball tunneled through to the other side.

Although scientists knew that particles could tunnel, until now, “it was not really clear how that happens, or what, precisely, the particle does,” says physicist Christoph Keitel of the Max Planck Institute for Nuclear Physics in Heidelberg, Germany. Theoretical physicists have long debated between two possible options. In one model, the particle appears immediately on the other side of the barrier, with no initial momentum. In the other, the particle takes time to pass through, and it exits the tunnel with some momentum already built up.

Keitel and colleagues tested quantum tunneling by blasting argon and krypton gas with laser pulses. Normally, the pull of an atom’s positively charged nucleus keeps electrons tightly bound, creating an electromagnetic barrier to their escape. But, given a jolt from a laser, electrons can break free. That jolt weakens the electromagnetic barrier just enough that electrons can leave, but only by tunneling.

Although the scientists weren’t able to measure the tunneling time directly, they set up their experiment so that the angle at which the electrons flew away from the atom would reveal which of the two theories was correct. The laser’s light was circularly polarized — its electromagnetic waves rotated in time, changing the direction of the waves’ wiggles. If the electron escaped immediately, the laser would push it in one particular direction. But if tunneling took time, the laser’s direction would have rotated by the time the electron escaped, so the particle would be pushed in a different direction.

Comparing argon and krypton let the scientists cancel out experimental errors, leading to a more sensitive measurement that was able to distinguish between the two theories. The data matched predictions based on the theory that tunneling takes time.
The conclusion jibes with some physicists’ expectations. “I’m pretty sure that the tunneling time cannot be instantaneous, because at the end, in physics, nothing can be instantaneous,” says physicist Ursula Keller of ETH Zurich. The result, she says, agrees with an earlier experiment carried out by her team.

Other scientists still think instantaneous tunneling is possible. Physicist Olga Smirnova of the Max Born Institute in Berlin notes that Keitel and colleagues’ conclusions contradict previous research. In theoretical calculations of tunneling in very simple systems, Smirnova and colleagues found no evidence of tunneling time. The complexity of the atoms studied in the new experiment may have led to the discrepancy, Smirnova says. Still, the experiment is “very accurate and done with great care.”

Although quantum tunneling may seem an esoteric concept, scientists have harnessed it for practical purposes. Scanning tunneling microscopes, for instance, use tunneling electrons to image individual atoms. For such an important fundamental process, Keller says, physicists really have to be certain they understand it. “I don’t think we can close the chapter on the discussion yet,” she says.

It’s hard not to compliment kids on certain things. When my little girls fancy themselves up in tutus, which is every single time we leave the house, people tell them how pretty they are. I know these folks’ intentions are good, but an abundance of compliments on clothes and looks sends messages I’d rather my girls didn’t absorb at ages 2 and 4. Or ever, for that matter.

Our words, often spoken casually and without much thought, can have a big influence on little kids’ views of themselves and their behaviors. That’s very clear from two new studies on children who were praised for being smart.

The studies, conducted in China on children ages 3 and 5, suggest that directly telling kids they’re smart, or that other people think they’re intelligent, makes them more likely to cheat to win a game.

In the first study, published September 12 in Psychological Science, 150 3-year-olds and 150 5-year-olds played a card guessing game. An experimenter hid a card behind a barrier and the children had to guess whether the card’s number was greater or less than six. In some early rounds of the game, a researcher told some of the children, “You are so smart.” Others were told, “You did very well this time.” Still others weren’t praised at all.

Just before the kids guessed the final card in the game, the experimenter left the room, but not before reminding the children not to peek. A video camera monitored the kids as they sat alone.

The children who had been praised for being smart were more likely to peek, either by walking around or leaning over the barrier, than the children in the other two groups, the researchers found. Among 3-year-olds who had been praised for their ability (“You did very well this time.”) or not praised at all, about 40 percent cheated. But the share of cheaters jumped to about 60 percent among the 3-year-olds who had been praised as smart. Similar, but slightly lower, numbers were seen for the 5-year-olds.

In another paper, published July 12 in Developmental Science, the same group of researchers tested whether having a reputation for smarts would have an effect on cheating. At the beginning of a similar card game played with 3- and 5-year-old Chinese children, researchers told some of the kids that they had a reputation for being smart. Other kids were told they had a reputation for cleanliness, while a third group was told nothing about their reputation. The same phenomenon emerged: Kids told they had a reputation for smarts were more likely than the other children to peek at the cards.
The kids who cheated probably felt more pressure to live up to their smart reputation, and that pressure may promote winning at any cost, says study coauthor Gail Heyman. She’s a psychologist at the University of California, San Diego and a visiting professor at Zhejiang Normal University in Jinhua, China. Other issues might be at play, too, she says, “such as giving children a feeling of superiority that gives them a sense that they are above the rules.”

Previous research has suggested that praising kids for their smarts can backfire in a different way: It might sap their motivation and performance.

Heyman was surprised to see that children as young as 3 shifted their behavior based on the researchers’ comments. “I didn’t think it was worth testing children this age, who have such a vague understanding of what it means to be smart,” she says. But even in these young children, words seemed to have a powerful effect.

The results, and other similar work, suggest that parents might want to curb the impulse to tell their children how smart they are. Instead, Heyman suggests, keep praise specific: “You did a nice job on the project,” or “I like the solution you came up with.” Likewise, comments that focus on the process are good choices: “How did you figure that out?” and “Isn’t it fun to struggle with a hard problem like that?”

It’s unrealistic to expect parents — and everyone else who comes into contact with children — to always come up with the “right” compliment. But I do think it’s worth paying attention to the way we talk with our kids, and what we want them to learn about themselves. These studies have been a good reminder for me that comments made to my kids — by anyone — matter, perhaps more than I know.

In the scientific version of her obituary, Dolly the Sheep was reported to have suffered from severe arthritis in her knees. The finding and Dolly’s early death from an infection led many researchers to think that cloning might cause animals to age prematurely.

But new X-rays of Dolly’s skeleton and those of other cloned sheep and Dolly’s naturally conceived daughter Bonnie indicate that the world’s first cloned mammal had the joints of normal sheep of her age. Just like other sheep, Dolly had a little bit of arthritis in her hips, knees and elbows, developmental biologist Kevin Sinclair of the University of Nottingham in England and colleagues report November 23 in Scientific Reports.
The researchers decided to reexamine Dolly’s remains after finding that her cloned “sisters” have aged normally and didn’t have massive arthritis (SN: 8/20/16, p. 6). No formal records of Dolly’s original arthritis exams were kept, so Sinclair and colleagues got Dolly’s and Bonnie’s skeletons and those of two other cloned sheep, Megan and Morag, from the National Museums Scotland in Edinburgh. Megan and Bonnie were both older than Dolly at the time of their deaths and had more bone damage than Dolly did. Morag died younger and had less damage.
Dolly’s arthritis levels were similar to those of naturally conceived sheep her age, indicating that cloning wasn’t to blame. “If there were a direct link with cloning and osteoarthritis, we would have expected to find a lot worse, and it would be more extensive and have a different distribution than what we’re finding in ordinary sheep,” says study coauthor Sandra Corr, a veterinary orthopedic specialist at the University of Glasgow in Scotland.
Dolly’s slightly creaky joints may have stemmed from giving birth to six lambs, including Bonnie. Pregnancy is a risk factor for arthritis in sheep.

Once billed as “the most beautiful woman in the world,” actress Hedy Lamarr is often remembered for Golden Age Hollywood hits like Samson and Delilah. But Lamarr was gifted with more than just a face for film; she had a mind for science.

A new documentary, Bombshell: The Hedy Lamarr Story, spotlights Lamarr’s lesser-known legacy as an inventor. The film explores how the pretty veneer that Lamarr shrewdly used to advance her acting career ultimately trapped her in a life she found emotionally isolating and intellectually unfulfilling.
Lamarr, born in Vienna in 1914, first earned notoriety for a nude scene in a 1933 Czech-Austrian film. Determined to rise above that cinematic scarlet letter, Lamarr fled her unhappy first marriage and sailed to New York in 1937. En route, she charmed film mogul Louis B. Mayer into signing her. Stateside, she became a Hollywood icon by day and an inventor by night.
Lamarr’s interest in gadgetry began in childhood, though she never pursued an engineering education. Her most influential brainchild was a method of covert radio communication called frequency hopping, which involves sending a message over many different frequencies, jumping between channels in an order known only to the sender and receiver. So if an adversary tried to jam the signal on a certain channel, it would be intercepted for only a moment.

During World War II, Lamarr partnered with composer George Antheil to design a frequency-hopping device for steering antisubmarine torpedoes. The pair got a patent, but the U.S. Navy didn’t take the invention seriously. “The Navy basically told her, ‘You know, you’d be helping the war a lot more, little lady, if you got out and sold war bonds rather than sat around trying to invent,’ ” biographer Richard Rhodes says in the film. Ultimately, the film suggests, Lamarr’s bombshell image and the sexism of the day stifled her inventing ambitions. Yet, frequency hopping paved the way for some of today’s wireless technologies.

Throughout Bombshell, animated sketches illustrate Lamarr’s inventions, but the film doesn’t dig deep into the science. The primary focus is the tension between Lamarr’s love of invention and her Hollywood image. With commentary from family and historians, as well as old interviews with Lamarr, Bombshell paints a sympathetic portrait of a woman troubled by her superficial reputation and yearning for recognition of her scientific intellect.

It’s still too early to pack your bags for TRAPPIST-1. But two new studies probe the likely compositions of the seven Earth-sized worlds orbiting the cool, dim star, and some are looking better and better as places to live (SN: 3/18/17, p. 6).

New mass measurements suggest that the septet probably have rocky surfaces and possibly thin atmospheres, researchers report February 5 in Astronomy & Astrophysics. For at least three of the planets, those atmospheres don’t appear to be too hot for life, many of these same researchers conclude February 5 in Nature Astronomy.
TRAPPIST-1 is about 40 light-years from Earth, and four of its planets lie within or near the habitable zone, the range where temperatures can sustain liquid water. That makes these worlds tempting targets in the search for extraterrestrial life (SN: 12/23/17, p. 25)

One clue to potential habitability is a planet’s mass — something not precisely nailed down in previous measurements of the TRAPPIST-1 worlds. Mass helps determine a planet’s density, which in turn provides clues to its makeup. High density could indicate that a planet doesn’t have an atmosphere. Low density could indicate that a planet is shrouded in a puffy, hydrogen-rich atmosphere that would cause a runaway greenhouse effect.

Using a new computer technique that accounts for the planets’ gravitational tugs on each other, astronomer Simon Grimm of the University of Bern in Switzerland and his colleagues calculated the seven planets’ masses with five to eight times better precision than before. Those measurements suggest that the innermost planet probably has a thick, viscous atmosphere like Venus, Grimm says. The other six, which may be covered in ice or oceans, may have more life-friendly atmospheres. The fourth planet from the star has the same density as Earth and receives the same amount of radiation from its star as Earth, Grimm’s team reports in Astronomy & Astrophysics.

“This is really the cool thing: We have one planet which is very, very similar to the Earth,” Grimm says. “That’s really nice.”
Having an atmosphere could suggest habitability, but not if it’s too hot. So using the Hubble Space Telescope, MIT astronomer Julien de Wit and his colleagues, including some members from Grimm’s team, observed the four middle planets as they passed in front of the star. The team was looking for a signature in near-infrared wavelengths of light filtering through planets’ atmospheres. That would have indicated that the atmospheres were full of heat-trapping hydrogen.

In four different observations, Hubble saw no sign of hydrogen-rich atmospheres around three of the worlds, de Wit and colleagues report in Nature Astronomy. “We ruled out one of the scenarios in which it would have been uninhabitable,” de Wit says.

The new observations don’t necessarily mean the planets have atmospheres, much less ones that are good for life, says planetary scientist Stephen Kane of the University of California, Riverside. It’s still possible that the star’s radiation blew the planets’ atmospheres away earlier in their histories. “That’s something which is still on the table,” he says. “This is a really important piece of that puzzle, but there are many, many pieces.”

Finishing the puzzle may have to wait for the James Webb Space Telescope, scheduled to launch in 2019, which will be powerful enough to figure out all the components of the planets’ atmospheres — if they exist.

On an expedition to an icy island chain off the Antarctic Peninsula’s northern tip, researchers discovered a massive supercolony of more than 1.5 million Adélie penguins, according to a study published March 2 in Scientific Reports.

Scientists had known of an Adélie penguin colony (Pygoscelis adeliae) in these Danger Islands, but satellite images revealed more guano on the rocky islands than could be explained by the colony’s expected numbers.

Even though the tiny island chain is only about 10 kilometers across, researchers hadn’t realized the extent of the penguin population, says study coauthor Heather Lynch, an ecologist at Stony Brook University in New York. “In the Antarctic, distances are so vast, something major could be just around the corner and you wouldn’t know.”
The researchers did a preliminary head count, took drone images and collected mud cores during a 2015 expedition. The team then spent about a year using a computer algorithm to analyze the images to more fully count 751,527 penguin nests, Lynch says. For every nesting bird, the scientists assumed there was a partner penguin out at sea.
Next, the team hopes to analyze the guano content in the collected layers of mud to discover how long the penguins have been nesting in the Danger Islands.
The discovery is good news for fans of the flightless bird. Elsewhere in Antarctica where the climate is more volatile, penguin colonies are in decline. “I hope this provides impetus for a marine protected area in the Danger Islands with expanded borders from what has been proposed,” Lynch says.

Archaeopteryx was a flapper, not just a glider. The shape of the ancient bird’s wing bones suggests it was capable of short bursts of active, flapping flight, similar to how modern birds like pheasants and quails fly to escape predators, a new study finds.

One of the earliest birds, Archaeopteryx lived about 150 million years ago during the Jurassic Period, spanning the evolutionary gap between modern birds and feathered dinosaurs. Fossils of the primitive fowl have been instrumental in the recognition that birds are dinosaurs (SN Online: 7/31/14). But researchers have long wrangled over how well these ancient dino-birds could fly.
Archaeopteryx doesn’t have several features considered essential to flight in modern birds, such as a keeled breastbone to which several important flight muscles attach; a ball-and-socket arrangement that allows the wing to flap fully up over the back and down again; and a muscle pulley system that links chest and shoulder muscles, allowing the birds to swiftly alternate between powerful downstrokes and upstrokes. Previous researchers also have suggested that Archaeopteryx’s plumage was too delicate and might have snapped with vigorous flapping (SN: 6/5/10, p. 12). Based on these observations, the primitive bird was thought to merely glide from branch to branch, rather than flapping its wings to fly.

Paleontologist Dennis Voeten and colleagues decided to look for other features that might indicate the dino-birds flapped their wings while flying. The researchers used X-ray microtomography to examine two different wing bones — the humerus, or upper arm bone, and a lower arm bone called the ulna — in three Archaeopteryx fossils.

The team compared the thickness of the bones’ walls and their resistance to torsion — a twisting force that birds’ wings withstand during flapping flight — with similar bones from several dinosaurs, flying reptiles called pterosaurs and modern birds. Archaeopteryx had wing bone structures most similar to pheasants and quails, birds that are capable of small bursts of active flapping flight, the researchers report March 13 in Nature Communications.

In examining the shape of the wing bones, the study takes a novel approach to the question of whether Archaeopteryx could fly, says ornithologist Gerald Mayr of the Senckenberg Research Institute Frankfurt, who was not involved in the research.
But the study doesn’t answer whether Archaeopteryx could launch itself from the ground into the air. “Their results convincingly show that it could do active flight” once it was already airborne, Mayr says. “What they do not explain is how it would have been possible to produce strong flapping flight to take off from the ground.” Other early birds might have used a combination of wing and leg strength to launch into the air, but this hasn’t been shown for Archaeopteryx (SN: 11/26/16, p. 9).

To understand whether and how Achaeopteryx actually flew, researchers would need to reconstruct the animal’s full range of motion — a challenging prospect given that muscles don’t fossilize, says Voeten, of Palacký University Olomouc in the Czech Republic.

The primitive birds, without flight adaptations such as the muscle pulley system, wouldn’t have been capable of the full range of flapping motion birds today use. Instead, other parts of its anatomy indicate Archaeopteryx may have thrown its wings upward and forward, similar to a swimmer’s butterfly stroke, Voeten says. “Dedicated studies would need to show if it would work that way.”

For decades, the name “virus” meant small and simple. Not anymore. Meet the giants.

Today, scientists are finding ever bigger viruses that pack impressive amounts of genetic material. The era of the giant virus began in 2003 with the discovery of the first Mimivirus (SN: 5/23/09, p. 9). The viral titan is about 750 nanometers across with a genetic pantry boasting around 1.2 million base pairs of DNA, the information-toting bits often represented with A, T, C and G. Influenza A, for example, is roughly 100 nanometers across with only about 13,500 base pairs of genetic material.

In 2009, another giant virus called Marseillevirus was identified. It is different enough from mimiviruses to earn its own family. Since 2013, mega-sized viruses falling into another eight potential virus families have been found, showcasing a long-unexplored viral diversity, researchers reported last year in Annual Review of Virology and in January in Frontiers in Microbiology.

Giant viruses mostly come in two shapes: polyhedral capsules and egglike ovals. But one, Mollivirus, skews more spherical. Pacmanvirus was named for the broken appearance of its outer shell. Both represent potential families. Two newly discovered members of the mimivirus family, both called tupanviruses and both with tails, have the most complete set of genes related to assembling proteins yet seen in viruses (SN Online: 2/27/18). Once unheard of, giant viruses may be common in water and soils worldwide. Only time — and more discoveries — will tell.
Virus length and genome size for a representative from each of two recognized giant virus families (mimivirus and marseillevirus families) and eight potential families are shown. Circles are scaled to genome size and shaded by size range, with influenza A and E. coli bacterium included for comparison. Years indicate when the first viruses were described.

Graphic: C. Chang; Sources: P. Colson, B. La Scola and D. Raoult/Annual Review of Virology 2017; J. Andreani et al/Frontiers in Microbiology 2018