TIME animals

There Was a Big Bang for Birds

An ex-crocodile. Clearly a step up
An ex-crocodile. Clearly a step up Luis Costa—AFP/Getty Images

A sweeping new study tells a long genetic tale

If there’s a factory where birds are built, the workers were clearly smoking something the day they designed the hummingbird. And the ostrich. And the toucan. Imagine, too, the pitch meeting for the parrot, (“Let’s make this one talk!”), or the peacock (“So we got this crate of feathers…”).

Of course, that’s not how it really happened. Birds came along without our help, evolving from the Aves class into 23 orders, 142 families, 2,057 genera and finally 9,702 species—the most prolific speciation of all four-limbed vertebrates. The problem with such prodigious divergence is that it makes it hard to determine how the great bird explosion began in the first place. Now, however, in a pair of papers in Science, scientists report that they have an answer. Modern birds, they have learned, got their start like the universe itself—with something of a Big Bang, a burst of specialization that began 65 million years ago with the same asteroid hit that wiped out the dinosaurs and made room for mammals and other land animals.

This finding results from the work of hundreds of scientists at 80 labs and universities across 20 countries, done with the help of bird tissue collected from labs and museums around the world. Those specimens were sent to the Genome Tissue Institute in Beijing, where the basic sequencing was conducted. The first and most basic conclusion the investigators reached was a big one. “This confirms that there was a very rapid radiation and that major lineages of birds were in existence 5 to 6 million years after the extinction event,” says Joel Cracraft, an avian systemicist at the American Museum of Natural History in New York and a contributor to the papers. “They were very widely distributed as well.”

But there was much more to be learned, and that required the hundreds of others scientists to get busy parsing the genomes. A lot of their results live down in the technical weeds, where geneticists speak of such things as total evidence nucleotide trees and GTR+GAMMA models. Among the plain-English findings, however, there were some important top-line results. The investigators identified a sort of progenitor bird, for example, a so-called apex predator that came along shortly after the asteroid hit and was the great-great-great granddaddy of all extant land birds. The descendants that that founding father left can be connected in unexpected ways.

The gaudy flamingo and the proletariat pigeon turn out to belong to sister clades—or groups descending from one common ancestor. Similarly, there is a three-way kinship among the cuckoos; the bustards (medium-size game birds that include the paauw and its larger cousin, the straightforwardly named great paauw); and the turacos. The last group is a brilliantly colored and plumed family of birds that include the African banana eaters and the go-away birds, species that got their names because one of them, well, eats bananas and the other issues a warning call that sounds like it’s saying “go away,” which it sort of is.

Among the more granular discoveries, the investigators report that so-called vocal learners—birds with flexible repertoires of songs and mimicked speech—actually share some of their molecular brain structures with humans. And the very act of singing appears to change the birds’ epigenomes—the regulatory system that sits atop the genes and determines which ones are expressed—meaning that the more frequent the song the more specialized the bird’s genetic wiring will become.

But just in case the big, fun, colorful Aves class gets above itself, the papers do stress that every extant bird can trace its line back even further than the apex predator, all the way to a small and rather vulgar group of ancestors that are actually alive today; the saltwater crocodile, the American alligator and the Indian gharial—which is sort of an alligator with an absurdly skinny snout. For birds as much as for humans, it seems, no matter how high you climb, there are always a few embarrassing family members to keep you humble.

TIME toxins

How an Ingredient in Airbags Might Turn Explosive

Ammonium nitrate, commonly used as a fertilizer, is also used in airbags

WSF logo small

An airbag can save your life, but if improperly manufactured, it could mean your death. At least five people have died after airbags made by Japanese company Takata exploded during deployment in crashes, bombarding passengers with sharp metal fragments. Now more than 14 million cars using the airbags are up for recall worldwide. The recall highlights a delicate balance of electrical, mechanical, and chemical processes inside an airbag—all of which are vulnerable to contamination and failure.

First, some background on how airbags work: Before an airbag deploys, the control unit has to detect a crash through various sensors on the car. Crash sensors are rigged to detect the sudden deceleration of a crash, but not be affected by the normal stopping and starting of driving. One form of sensor is the “ball and tube” setup, where a small metal ball is held in place by a magnet. In the event of a collision, the ball detaches from the magnet, rolls down and completes an electrical circuit that triggers the inflation. Similar sensors use weights connected to a coiled-up spring that unrolls with a sudden stop. Another type of sensor can be located inside the front doors, where it monitors air pressure; a collision from the side that pushes the door inwards will change the air pressure, and trip the sensor.

WORLD SCIENCE FESTIVAL: How To Survive A Spaceship Disaster

If the sensor detects a crash, it tells the airbag’s inflator system to kick into gear. Most airbags are inflated when the inflator unit ignites a pellet of a compound called sodium azide (NAN3), kickstarting a swift chemical reaction that fills up the airbag with nitrogen gas (N2), sending it bursting out to cushion a car’s occupants. All of this happens within less than half the time it takes you to blink once.

But in the 1990s, Takata started looking for alternatives to sodium azide, due to the fact that the compound could release toxic fumes when the airbags deployed. First, the company’s engineers replaced the sodium azide with a compound called tetrazole. But tetrazole, while less toxic than sodium azide, proved more expensive. Eventually, over the objections of some employees, Takata developed a propellant using the ammonium nitrate (NH4NO3), more commonly used as a fertilizer.

WORLD SCIENCE FESTIVAL: Why Lethal Injections Fail

Ammonium nitrate “shouldn’t be used in airbags,” Missouri University of Science and Technology explosives expert Paul Worsey told the New York Times, saying the compound is really better for large-scale demolitions. “But it’s cheap, unbelievably cheap.”

Part of the danger with ammonium nitrate lies in the compound’s ability to transition through various solid states due to changes in temperature, pressure and moisture. The transition point between state IV, called beta-rhombic, and state III, called alpha-rhombic, occurs at 32.3 degrees Celsius (89.6 degrees Fahrenheit). The temperature cycles that a car experiences through days and nights, especially in hotter and more humid areas, may be enough to cause the compound to switch between these crystalline states, making it less stable.

WORLD SCIENCE FESTIVAL: Some Assembly Required

Takata senior vice president Hiroshi Shimizu told U.S. lawmakers in early December that the true cause of the airbag ruptures is still unknown, and the company has advocated for recalls to be limited to humid regions. Meanwhile, while still not characterizing its airbag propellant as defective, Takata has quietly modified the recipe for the propellant used in the replacement bags for recalled cars—though ammonium nitrate still remains a key component.

This article originally appeared on World Science Festival.

TIME Culture

‘Men Are Idiots’, New Study Says

Researchers support the theory that men are more likely than women to take "idiotic" risks

A new analysis published Thursday shows men are more likely to engage in stupidly risky behavior than women, supporting the ‘Male Idiot Theory’ previously indicated in studies of financial risk taking and hospital records.

Researchers examined the data on winners of the Darwin Award over the past twenty years and published their findings in the British Medical Journal that 88.7% of the award-winners were male.

Every year, Darwin Awards are symbolically given to around a dozen people who manage to die in such an extraordinarily idiotic manner that they ensure the long-term survival of the human species, by removing one idiot from the gene pool.

Looking at the behavior of those who qualified for the Darwin Awards, it would appear that some of these risks are indeed exceptionally stupid. Take for instance the terrorist who mailed a letter bomb with too few postage stamps and, on its return, opened his own letter and was “blown away”, says the Darwin Awards website. Or the man from South Carolina who had disguised himself by spray painting his face gold during an armed robbery, and died from the toxic paint fumes.

The scientists noted some limitations to their research — for instance idiotic male candidates may have been more newsworthy than idiotic women — but nevertheless concluded that “men are idiots and idiots do stupid things.”

TIME On Our Radar

Melting Away: Stunning Photos of Disappearing Icebergs

After spending 10 years making portraits of icebergs, Camille Seaman is worried that the next generation may never see these wonders at all

When photographer Camille Seaman was a little girl, one of her favored moments was walking through the woods with her grandfather outside their family house in Long Island, N.Y.

“He would introduce me to the trees,” Seaman tells TIME. “He would say, ‘These trees are your relatives in the same way I am your relative, and you must respect them. You cannot think that you are separate and can abuse them.’”

That way of thinking and her Native American upbringing have followed Seaman, 45, on a decade-long project documenting the delicate polar environment. Her ability to relate to icebergs and glaciers as individuals with distinct personalities has helped her capture their breath-taking yet very intimate portraits. Some of them she knows as persistent, the never-say-never type that drifts in the sea for years until they are little pieces of ice; some are in low spirits, ready to give up, and they can be gone in a moment.

“I don’t see them as just chunks of ice or some frozen water,” she says. “When I see them, I really see all of the history and time that went into making them as exactly what they are.”

Seaman’s journey began with a “comic mishap” as she calls it. In 1999, Her flight was overbooked, and she volunteered to give up her seat in exchange of a round-trip ticket to go to Alaska. As she started walking on the squeaky, dry ice, Seaman had an awakening. “That’s the first time [that I understood] I was standing on my planet,” she says. “Not just a planet or earth, but my planet.”

In the following years, Seaman couldn’t resist revisiting the polar regions. She found a job working as an expedition photographer on ships carrying scientists and tourists to the Arctic and Antarctic. What was really lovely about the job was I got to really photograph it the way I wanted to photograph it. I had access to a lot of time,” she says.

But being two to three months away on the ship came at a great expense for her family, especially after her daughter was born.

“What kind of mother are you to leave your daughter for months at a time?” she remembers critics saying. “I have to tell them, truly: What kind of mother am I to tell my daughter to go out and live her dreams, be everything she wants to be, if I’m not doing that as an example.”

Seaman says she has instead bounded with her daughter in a deeper, more intense relationship, in which they bypass the mundane talk about homework and focus more on sharing their insights and values about the world.

Her daughter, now 14, has been to more than 100 countries. She saw her first polar bear at three and turned five in the Arctic. “It turned out that when I walked on the ice in Alaska I was actually pregnant with her, so she’s been with me on this entire journey in some form,” Seaman says. She has dedicated her new book, Melting Away, to her, who she says is a driving force for her to continue bringing images to people and raise awareness about preserving the polar icecaps for generations to come.

Unfortunately, this decade-long expedition came to its end in the summer of 2011, when she was photographing in the Arctic on Hurtigruten, an ultramodern Norwegian expedition cruise. The weather was warm, flowers blooming. With little sea ice, their ship was able to travel very far north. The trip, expected to be a comfortable and pleasant voyage, failed to enlighten Seaman and researchers but worried them.

The lack of ice also drove starved polar bears to land, which Seaman remembers as nerve-wrecking. She recently had heard news that a British teenager camper was mauled to death by a hungry bear in Norway. The bear was shot dead, and Seaman felt responsible.

“I never wanted to be the reason that a bear lost its life,” she says. “I just became acutely aware that I was part of the problem – Me, traveling thousands of miles in airplanes and fossil-burning ships. It became my own personal conflict of interest, like I care about the bears and the environment, but I’m a hypocrite if I keep coming.”

She was also frustrated, pondering whether her photographs made a difference. I just felt a degree of despair. I thought maybe I’m just lacking the skill to communicate clearly in a way people will care. Maybe these photographs aren’t just enough.”

Seaman applied to become a Ted Fellow in the same year. The program helped mentor her in how to convey her ideas and garnered exposure for her venues. She has since been a prominent speaker discussing the polar regions and the danger of climate change.

Camille Seaman‘s new book Melting Away is available now. Her work will be exhibited at the Half King restaurant and gallery in New York beginning Dec. 16.

Ye Ming is a contributor to TIME LightBox. Follow her on Twitter and Instagram.

TIME europe

The E.U. Plans to Spike Key Clean-Air and Recycling Laws

Prime Minister David Cameron Tries To Take A Harder Line with Europe
E.U. flags are pictured outside the European Commission building in Brussels on Oct. 24, 2014 Carl Court—Getty Images

The proposed laws are aimed at preventing tens of thousands of premature deaths and set a 70% recycling target by 2030

The E.U. is planning to scrap environmental laws aimed at averting tens of thousands of possible deaths, according to classified documents published on Thursday.

The leaked files propose the withdrawal of a plan for a clean-air law as well as a directive setting a target of 70% waste recycling by 2030, the Guardian reported.

The plan is reportedly being withdrawn because the commission in charge of it sees “no foreseeable agreement” with states that have a poor track record on recycling, and would not be able to meet the target without additional financial help.

Read more at the Guardian

TIME weather

A Rare Weather Phenomenon Is Causing a Sea of Clouds to Fill the Grand Canyon

Grand Canyon Clouds
This photo provided by the National Park Service shows dense clouds at the south rim of the Grand Canyon on Dec. 11, 2014 in Arizona. Maci MacPherson—;AP

The fog is able to stick and build up in the Grand Canyon when there is no wind

A rare weather phenomenon has caused the Grand Canyon to fill up with fog.

The weather pattern is called a “total cloud inversion” and occurs when clouds are forced down by warm air and cannot rise, the Associated Press reports.

Instead of the usual stunning views, visitors to the national park gaze out over a fluffy white blanket.

The National Weather Service in Arizona says the phenomenon happens every few years.

For those planning on visiting one of the world’s most famous natural wonders, the fog is expected to dissipate after Thursday.

[AP]

TIME dinosaurs

Here’s What Really Killed the Dinosaurs

dinosaur volcano
Elena Kalistratova—Getty Images

It wasn't just an asteroid

At the start of the 1980s, the question of what forced dinosaurs and huge numbers of other creatures to become extinct 65 million years ago was still a mystery. By the decade’s end, that mystery was solved: a comet or asteroid had slammed into Earth, throwing so much sun-blocking dust into the air that the planet plunged into a deep-freeze. The discovery of a massive impact crater off the coast of Mexico, of just the right age, pretty much sealed the deal in most scientists’ minds.

But a second global-scale catastrophe was happening at much the same time: a series of ongoing volcanic eruptions that dwarf anything humans have ever seen. They were so unimaginably powerful that they left nearly 200,000 square miles (518,000 sq. km) of what’s now India buried in volcanic basalt up to a mile and a half thick. And the gases and particulate matter spewed out by those eruptions, argue at least some scientists, could have played a big role in the dinosaurs’ doom as well.

How big a role, however, depends on exactly when the eruptions began and how long they lasted, and a new report in Science goes a long way toward answering that question. “We can now say with confidence,” says Blair Schoene, a Princeton geologist and lead author of the paper, “that the eruptions started 250,000 years before the extinction event, and lasted for a total of 750,000 years.” And that, he says, strengthens the idea that the eruptions could have contributed to the mass extinction of multiple species.

Schoene and his co-authors don’t claim volcanoes alone wiped out the dinosaurs; only that they changed the climate enough to put ecosystems under stress, setting them up for the final blow. “We don’t know the exact mechanism,” he admits. Volcanoes emit carbon dioxide, which could have triggered an intense burst of global warming, but they also emit sulfur dioxide, which could have caused global cooling. “What we do know,” Schoene says, “is that earlier mass extinctions were caused by volcanic eruptions alone.” The new dates, he and his co-authors believe, will help scientists understand what role these volcanoes played in the dinosaurs’ demise.

If there was such a role, that is, and despite this new analysis, plenty of paleontologists still doubt it seriously. The dating of the eruptions, based on widely accepted uranium-lead measurement techniques, is not an issue, says Brian Huber, of the Smithsonian Institution. “That part of the science is great,” he says. “It moves things forward.”

But the link between eruptions and the disappearance of species, he thinks, is invalid. “The case of the mass extinctions being caused by an impact is overwhelming,” says Huber. “One of the wonderful things about these arguments is that they’ve forced us to look really carefully at the fossil evidence, on land and at sea. We’ve accumulated a really detailed data set.”

And those data, Huber says, make it clear that the extinction rate for the 250,000 years leading up to the asteroid impact wasn’t especially large. Then, at the time of the impact: whammo. The idea that volcanoes played a significant role in this extinction event keeps coming up every so often, and in Huber’s view, “the argument has gotten very tiresome. I no longer feel the need to put any energy into it. It’s from a minority arguing against overwhelming evidence.”

For onlookers, that might seem harsh—not to mention overconfident. Sometimes a vocal scientific minority turns out to be right in its challenge to the scientific mainstream, as when Alfred Wegener argued, to much ridicule, that continents move around the Earth. And sometimes it’s dead wrong—Sir Fred Hoyle’s futile campaign against the Big Bang theory, for example.

In both cases, however, it was the accumulation of evidence that ultimately vindicated one argument and torpedoed the other. So far, the volcanic impact people have most of the torpedoes on their side.

Read next: Newly Discovered Fossils Reveal Goofy-Looking Dinosaur

TIME Science

Apollo 17 and the Case for Returning to the Moon

Harrison H. Schmitt on moon
Apollo 17 astronaut Jack Schmitt standing on surface of moon while holding a rake full of rock samples, with Rover in distance Time Life Pictures / Getty Images

It's been two generations since the moon was eclipsed in NASA's priorities

Richard Nixon was a lunar buzzkill—but at least he was honest about it. During the early years of the space program, Nixon held no political office, which put him on the sidelines for all of the one-man Mercury flights and two-man Gemini flights, as well as the first two flights of the Apollo program. But he assumed the presidency in January of 1969 and was thus the one who got to spike the football in July of that year, phoning the moon from the Oval Office to congratulate the Apollo 11 crew on their historic lunar landing.

Not long afterward, the same President canceled the Apollo program—though he held off on making his announcement until after his reelection in 1972 was assured.

During the final lunar landing mission—Apollo 17, which left Earth on Dec. 7, 1972 and reached the moon on Dec. 11—Nixon was candid about what the future held for America’s exploratory ambitions, and it was not good. “This may be the last time in this century that men will walk on the moon,” he said in a formal pronouncement.

As it turned out, things have been even bleaker than that. It’s been 42 years since Apollo 17 commander Gene Cernan climbed up the ladder of his lunar module, leaving the final human footprint in a patch of lunar soil. TIME’s coverage of the mission provides not only an account of the events, but a sense—unintended at the time—of just how long ago they unfolded. There are the quotation marks that the editors thought should accompany the mention of a black hole, since really, how many people had actually heard of such a thing back then? There was, predictably, the gender bias in the language—with rhapsodic references to man’s urge to explore, man standing on the threshold of the universe. It may be silly to scold long-ago writers for such usage now—but that’s not to say that, two generations on, it doesn’t sound awfully odd.

Over the course of those generations, we’ve made at least one feint at going back to the moon. In 2004, then-President George W. Bush announced a new NASA initiative to return Americans to the lunar surface by 2020. But President Obama scrapped the plan and replaced it with, well, no one is quite certain. There’s a lot of talk about capturing a small asteroid and placing it in lunar orbit so that astronauts can visit it—a mission that is either intriguing, implausible or flat-out risible, depending on whom you talk to. And Mars is on the agenda too—sort of, kind of, sometime in the 2030s.

But the moon, for the moment, is off America’s radar—and we’re the poorer for it. There were nine manned lunar missions over the course of three and a half glorious years, and half a dozen of them landed. That makes six small sites on an alien world that bear human tracks and scratchings—and none at all on the the far side of that world, a side no human but the 24 men who have orbited the moon have seen with their own eyes.

We tell ourselves that we’ve explored the moon, and we have—after a fashion. But only in the sense that Columbus and Balboa explored the Americas when they trod a bit of continental soil. We went much further then; we could—and we should—go much further now. In the meantime, TIME’s coverage of the final time we reached for—and seized—the moon provides a reminder of how good such unashamed ambition feels.

Read a 1973 essay reflecting on the “last of the moon men,” here in the TIME Vault: God, Man and Apollo

TIME space

You Can Quit Thanking Comets for Your Water

Comet 67P: Does this thing look like it could quench your thirst?
Comet 67P: Does this thing look like it could quench your thirst? ESA

A new finding from the Rosetta spacecraft upsets a longstanding theory

There was no shortage of drama when the European Space Agency’s probe Philae set down on a comet last month—the first such landing in history. First Philae bounced, then it bounced again, ending up with one of its three legs sticking up in the air, and in the shadow of a cliff that prevented its solar panels from recharging its batteries. For two days, the probe hurried to complete whatever science it could….and then everything went black.

But that hardly spelled the end of the mission. Philae’s mother ship, Rosetta, has continued to orbit comet 67P/Churyumov–Gerasimenko, as it’s been doing since August, taking measurements and images of unprecedented quality. And with nearly a year of close-up observations to go, Rosetta has already come up with one result, described in a new paper in Science, that chief scientist Matt Taylor, of the European Space Agency, labeled “fantastic”: Earth’s oceans, the scientists have concluded, were evidently not created by impacts from comets rich with water ice, despite earlier evidence to the contrary. “We have to conclude instead,” said lead author Kathrin Altwegg, a planetary scientist at the University of Bern, at a press conference, “that the water came from asteroids.”

That’s a big reversal from what scientists were thinking just a few years ago. Back in 2011, the European Herschel space telescope took a hard look at Comet Hartley 2 and determined that its own cache of water, detected as vapor boiling away as Hartley approached the Sun, had a chemical composition very similar to what we see on Earth. It’s all H2O, but some of the H is a rare form of hydrogen known as deuterium, whose atoms carry not just a proton like the ordinary stuff, but a neutron as well. Water molecules made with deuterium are known as “heavy water,” and about three in a thousand water molecules on Earth’s surface are the heavy kind.

Measurements of Halley’s Comet back in the mid-80’s showed a deuterium-to-hydrogen ratio about twice that high, which argued against the idea that comets delivered water to a bone-dry Earth early in the Solar System’s history. But Halley’s came from the Oort Cloud, a spherical swarm of proto-comets orbiting at the far edges of the Solar System. Hartley 2 came from the Kuiper Belt of comets, which lies just beyond Neptune–not exactly nearby, but a whole lot closer. Given what Herschel found at Hartley 2, it appeared that Kuiper belt comets are chemically different from those that hail from the Oort cloud. If so, our water could have cometary origins after all.

The new results from Rosetta say no: Comet 67P, which also comes from the Kuiper belt, has an even greater proportion of heavy water than Halley’s and other Oort cloud objects. Even if significant numbers of comets do have Earthlike water, some clearly don’t—and even a relative few would have made Earth’s proportion of heavy water higher than it is. It’s arguable that 67P is pretty much unique among its Kuiper Belt brethren in having so much deuterium. “That’s not impossible,” said Altwegg dubiously “but….”

If comets didn’t bring us water, and if the Earth was too hot in its youth to hold on to what surface water it might have started out with, there’s still one plausible water carrier. “Today, said Taylor at the press conference, “we know asteroids have very little water, but that was probably not always the case.” The solar system was bombarded by asteroids early in its history, and if they were indeed wetter than they are now, that explains where the water in our oceans, in our seltzer bottles, in our bodies and everywhere else comes from.

Important as this new finding is, it’s likely to be only the first of many Rosetta will make as it rides along with 67P for the next year or so, watching carefully as the warming rays of the Sun bring the comet to life. “It’s a nice start to the science phase of the mission,” Taylor said.

And if you think you’ve heard the last of the Philae lander, think again. Mission controllers are still trying to pinpoint Philae’s precise location on 67P’s surface. That will allow scientists to do at least one more experiment: they’ll send radio pings from Rosetta through body of the comet to bounce off Philae and back to Rosetta. By examining how the radio beams are altered en route, they will be able to figure out whether 67P’s insides are rock-solid or held together relatively loosely.

Locating Philae would also allow scientists to calculate whether the lander might be brought back from the dead six months from now. It’s just possible, said Taylor, that a change in 67P’s orientation could bring Philae back into the sunlight, allowing its solar panels to recharge its batteries. If that happens, the prospects for extraordinary science from this already wildly successful mission will be even greater.

TIME

Punishing Kids for Lying Only Makes Them Lie More

Young child sitting in corner as punishment
Getty Images

Kids who are given a moral reason to tell the truth tend to do so more often

Do you punish your children when they’re caught in a lie? That’s what many parents do, but a new study from researchers at McGill University suggests it might be time for a different approach. The study finds that kids reprimanded for lying are more likely to bend the truth, while kids who are given a moral reason for truth-telling tend to believe that honesty is the best policy.

Researchers traced the effectiveness of punishment in 372 kids between the ages of 4 and 8, finding that children were less likely to tell the truth when threatened with punishment, and more likely to tell the truth when they thought it would please an adult.

In order to gauge the implications of punishment on a child’s propensity to lie, researchers placed each participant alone in a room with a toy, and asked the child not to peek at the toy for an entire minute. It’s hardly surprising that curiosity got the best of most children, with 67.5 percent peeking, and 66.5 percent of those who peeked going on to lie about it. (Note: older children were less likely to peek, but were also more likely to lie about peeking after they’d done so.)

“Children often lie to conceal transgressions,” says study researcher and McGill professor Victoria Talwar. “Having done something wrong or broken a rule, they may choose to lie to try to conceal it. After all, they know they may get in trouble for the transgression. Thus, punishment doesn’t have much of an effect. It doesn’t deter them from using the strategy of lying to try to get out of trouble.”

So, how should parents go about encouraging their children to tell the truth when the impulse to lie is so strong? McGill’s study indicates that kids respond best to a strong moral appeal for honesty. Younger children were inclined to tell the truth to make an adult happy, while older children were inclined to do so because of their own internalized definition of right and wrong –– facts that might come in handy when your little one is caught red handed with the leftover Halloween candy.

“Threats about punishment are not deterrents for lying, and they do not communicate why children should be honest,” says Talwar. “If a child is playing with a ball in the house and breaks your vase but tells the truth about it when asked, you should recognize that he came clean. He may still have consequences for his transgression, but the child learns that honesty is valued.”

These findings reinforce a more progressive approach to parenting, and indicate that it’s better to explain truth-telling to children using positive reinforcement than the threat of harsh consequences. “Globally, we generally think of lying as a negative behavior,” says Talwar. “However, we sometimes fail to recognize the positive behavior –– honesty. If a child is confessing his transgression, we need to recognize that he was honest.”

Read next: Parents Should Try Being Present Instead of Perfect

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