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It’s not the size of a snake’s muscles that matter, but how it uses them. King snakes can defeat larger snakes in a wrestling match to the death because of how they coil around their prey, researchers report March 15 in the Journal of Experimental Biology.

King snakes wrap around their food and squeeze with about twice as much pressure as rat snakes do, says David Penning, a functional morphologist at Missouri Southern State University in Joplin. Penning, along with colleague Brad Moon at the University of Louisiana at Lafayette, measured the constriction capabilities of almost 200 snakes. “King snakes are just little brutes,” Penning says.
King snakes, which are common in North American forests and grasslands, are constrictor snakes that “wrestle for a living,” Penning says. They mainly eat rodents, birds and eggs, squeezing so hard, they can stop their prey’s heart (SN: 8/22/15, p. 4). In addition, about a quarter of the king snake diet is other snakes. King snakes can easily attack and eat vipers because they’re immune to the venom, but when they take on larger constrictors, such as rat snakes, it has been unclear what gives them the edge. “That’s not how nature goes,” Penning says, because predators are usually larger than their prey.

King snakes, though, can eat snakes up to 35 percent larger than themselves. One of the largest king snake conquests on record, from 1893, is of a 5-foot-3-inch rat snake, about 17 percent larger than the 4-foot-6-inch king snake that consumed it, Penning says.
“David Penning is really one of the first researchers that has been looking at the anatomy, physiology and function of these snakes” to understand how king snakes are superior to rat snakes, says Anthony Herrel, a functional morphologist and evolutionary biologist at the French National Museum of Natural History in Paris.
To determine what makes these snakes kings, Penning and Moon compared their muscle size, ability to escape attack and the strength of their squeeze to that of rat snakes. In one test, the researchers shook dead rodents enticingly in front of the snakes to goad them into striking and squeezing. Sensors on the rodents recorded the pressure of the squeeze.

The king snakes constricted with an average pressure of about 20 kilopascals, stronger than the pumping pressure of a human heart. Rat snakes in the same tests applied only about 10 kilopascals of pressure.

But the king snakes weren’t bigger body builders. Controlling for body size, the two kinds of snakes “had the exact same quantity of muscle,” Penning says.

The snakes’ more powerful constriction is probably due to how they use their muscles, not how much muscle they have, the researchers conclude. They observed that the majority of king snakes in the study wrapped around their food like a spring in what Penning calls the “curly fry pattern.” Rat snakes didn’t always coil in the same way and often ended up looking like a “weird pile of spaghetti,” he says.

Penning plans to study how other factors influence constriction as well, such as how long the king snakes can squeeze, how hungry they are and the temperature of their environment.

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.

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.

NEW ORLEANS — Saturn’s mighty rings cast a long shadow on the gas giant — and not just in visible light.

Final observations from the Cassini spacecraft show that the rings block the sunlight that charges particles in Saturn’s atmosphere. The rings may even be raining charged water particles onto the planet, researchers report online December 11 in Science and at the fall meeting of the American Geophysical Union.

In the months before plunging into Saturn’s atmosphere in September (SN Online: 9/15/17), the Cassini spacecraft made a series of dives between the gas giant and its iconic rings (SN Online: 4/21/17). Some of those orbits took the spacecraft directly into Saturn’s ionosphere, a layer of charged particles in the upper atmosphere. The charged particles are mostly the result of ultraviolet radiation from the sun separating electrons from atoms.
Jan-Erik Wahlund of the Swedish Institute of Space Physics in Uppsala and Ann Persoon of the University of Iowa in Iowa City and their colleagues examined data from 11 of Cassini’s dives through the rings. The researchers found a lower density of charged particles in the regions associated with the ring shadows than elsewhere in the ionosphere. That finding suggests the rings block ultraviolet light, the team concludes.

Blocked sunlight can’t explain everything surprising about the ionosphere, though. The ionosphere was more variable than the researchers expected, with its electron density sometimes changing by more than an order of magnitude from one Cassini orbit to the next.

Charged water particles chipped off of the rings could periodically splash into the ionosphere and sop up the free electrons, the researchers suggest. This idea, known as “ring rain,” was proposed in the 1980s (SN: 8/9/86, p. 84) but has still never been observed directly.

OXON HILL, Md. — Astronomers may soon know for sure if Europa is spouting off. After finding signs that Jupiter’s icy moon emits repeating plumes of water near its southern pole, astronomers using the Hubble Space Telescope hope to detect more evidence of the geysers.

“The statistical significance is starting to look pretty good,” astronomer William Sparks of the Space Telescope Science Institute in Baltimore says. He presented preliminary results on the hunt for the plumes at a meeting of the American Astronomical Society on January 9.
Sparks’ team started observing Europa on January 5, hoping to catch it passing in front of Jupiter 30 times before September. Hubble can detect active plumes silhouetted against background light from Jupiter. If the plume repeats as often as it seems to, “it’s essentially a certainty we’ll see it again if it’s real,” Sparks said.

Europa probably hosts a vast saltwater ocean buried under a thick icy shell. In 2012, astronomers using Hubble spotted high concentrations of hydrogen and oxygen over Europa’s southern hemisphere — signs that Europa was spitting water into space (SN: 1/25/14, p. 6). Later efforts to find those signs using the same technique yielded nothing.

But using Jupiter as a backdrop for the plumes, Sparks and his colleagues spotted several eruptions (SN Online: 9/26/16) — once in March 2014, again in February 2016 and possibly also in March 2017, Sparks said.

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Maps of Europa’s heat and ionosphere made by the Galileo spacecraft in the 1990s show the plumes’ location was warmer than the surrounding ice. It also had an unusually high concentration of charged particles, perhaps the result of water splitting into hydrogen and oxygen. Both observations support the idea that some ocean is escaping at that spot.

“If it’s a coincidence, it’s a hell of a coincidence,” Sparks says.

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.

Hunter-gatherers and farming villagers don’t write parenting handbooks, much less read them. But parents in WEIRD societies — Western, educated, industrialized, rich and democratic — can still learn a few childrearing lessons from their counterparts in small-scale societies.

It’s not that Western parents and kids are somehow deficient. But we live in a culture that holds historically unprecedented expectations about how to raise children. Examples: Each child is a unique individual who must be allowed to make decisions independently; children are precious and innocent, so their needs are more important than those of adults; and kids need to be protected from themselves by constant adult supervision.
When compared to family life in foraging and farming cultures, and in WEIRD societies only a few decades ago, there is nothing “normal” about parenting convictions such as these.

“Childhood, as we now know it, is a thoroughly modern invention,” says anthropologist David Lancy of Utah State University in Logan. He has studied traditional societies for more than 40 years.

In his book Raising Children: Surprising Insights from Other Cultures, Lancy examines what’s known about bringing up kids in hunter-gatherer groups and farming villages. Among the highlights:

Babies are usually regarded as nonpeople, requiring swaddling and other special procedures over months or years to become a human being.
Children are typically the lowest-ranking community members.
Because kids can’t feed and protect themselves, they accumulate a moral debt to their elders that takes years of hard work to repay.
If that sounds harsh to WEIRD ears, withhold judgment before considering these child-rearing themes from traditional cultures.

Allow for make-believe about real life
Hunter-gatherer and village kids intently observe and imitate adults (SN: 2/17/18, p. 22). Playtime often consists of youngsters of various ages acting out and even parodying adult behaviors. Virtually everything, from relations between the sexes to religious practices, is fair game. Kids scavenge for props, assign each other roles and decide what the cast of characters will say.

Western children would benefit from many more chances to play in unsupervised, mixed-age groups, Lancy says.

Let kids play collaborative games
A big advantage of play groups of kids of all ages is that they become settings for games in which kids negotiate the rules. Until recently, these types of games, such as marbles, hopscotch and jump rope, were common among U.S. children.

Not anymore, at least not in neighborhoods dominated by adult-supervised play dates and sports teams. Sure, tempers can flare as village youngsters hash out rules for marbles or jacks. But negotiations rarely go off the rails. Older kids handicap themselves so that younger children can sometimes win a game. Concessions are made even for toddlers.

The point is to maintain good enough relations to keep adults from intruding. In modern societies, Lancy suspects, bullying flourishes when kids don’t learn early on how to play collaboratively.

Put young children to work
In most non-WEIRD societies, miniature and cast-off tools and utensils, including knives, are the toys of choice for kids of all ages. Play represents a way to prepare for adult duties and, when possible, work alongside adults as helpers.

Western parents can find ways for preschoolers to help out around the house, but it demands flexibility and patience. Lancy suggests making allowances for a 3-year-old who mixes up socks when sorting the laundry. Maybe paper plates are needed until a kitchen helper becomes less apt to drop them.

Still, carefully selected jobs for 3- and 4-year-olds promote a sense of obligation and sympathy toward others, Lancy says. Western kids given chances to help adults early on may, like their non-WEIRD peers, willingly perform chores at later ages, he predicts.

Whether children live in city apartments or forest huts, having the freedom to explore and play with no adults around proves an antidote to boredom. Lancy recalls how boredom-busting works from his own early childhood in rural Pennsylvania during the 1950s. His family lived in a house bordering a river. Lancy would sit on the river bank for up to an hour at a time. His mother liked to tell visitors a story that, when asked what he had been doing, the boy replied “watching the ‘flections.”