Paleontologists Find 110-Million-Year-Old Wood-Boring Trace Fossil (Paleontology)

A team of paleontologists from the University of Alberta has found the fossilized tracks of a marine wood-boring organism that lived approximately 110 million years ago (Cretaceous period).

Apectoichnus lignummasticans. Image credit: Melnyk et al, doi: 10.1017/jpa.2020.63.

Trace fossils are biologically produced sedimentary structures that include tracks, trails, burrows, borings, fecal pellets, and other traces.

Also known as ichnofossils, they represent behavior instead of the preserved remains of specific organisms.

The new trace fossil was found in a core from a wellbore near Bushy Lake, west-central Saskatchewan, Canada.

Named Apectoichnus lignummasticans, it came from the lagoonal deposits of the Lower Cretaceous Sparky Formation.

The fossil is similar in many respects to modern borings in wood that are produced by marine isopods, such as Limnoria lignorum, for feeding and refugia.


References: Scott Melnyk et al. A new marine woodground ichnotaxon from the Lower Cretaceous Mannville Group, Saskatchewan, Canada. Journal of Paleontology, published online August 17, 2020; doi: 10.1017/jpa.2020.63 link: https://www.cambridge.org/core/journals/journal-of-paleontology/article/new-marine-woodground-ichnotaxon-from-the-lower-cretaceous-mannville-group-saskatchewan-canada/472CEB5DBCDCA28D292BCAC7ED869EEC

Astronomers Find Misaligned and Warped Protoplanetary Disk around Triple-Star System (Astronomy)

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) and the SPHERE (Spectro-Polarimetric High-contrast Exoplanet Research) instrument on ESO’s Very Large Telescope (VLT) have discovered a rare circumtriple protoplanetary disk with misaligned dust rings around the young hierarchical triple system GW Orionis. They give two possible scenarios for the misalignment: either the disk was torn apart by the gravitational pull from the stars, or by a newborn planet.

ALMA, in which ESO is a partner, and the SPHERE instrument on ESO’s Very Large Telescope have imaged GW Orionis, a triple star system with a peculiar inner region. The new observations revealed that this object has a warped planet-forming disc with a misaligned ring. In particular, the SPHERE image (right panel) allowed astronomers to see, for the first time, the shadow that this ring casts on the rest of the disc. This helped them figure out the 3D shape of the ring and the overall disc. The left panel shows an artistic impression of the inner region of the disc, including the ring, which is based on the 3D shape reconstructed by the team. Credit: ESO/L. Calçada, Exeter/Kraus et al.

GW Orionis is a triple-star system located approximately 1,312 light-years away in the constellation of Orion.

The two inner stars, GW Orionis A and B, orbit each other and are separated by 1 AU (astronomical units). The third star, GW Orionis C, orbits its two siblings at a distance of roughly 8 AU.

In new research, two independent teams of astronomers pointed ALMA at GW Orionis.

They found three separate rings with different orientations in the massive protoplanetary disk of the triple system, located roughly 46, 185, and 340 AU from its center.

The inner ring is very misaligned relative to both the outer rings and the three stars. The outermost ring is the largest ever observed in protoplanetary disks.

If a planet would be forming in the gap between the inner and outer ring, it would be located incredibly far away from the stars. For comparison, Neptune is only about 30 AU from the Sun.

The second team, led by University of Exeter’s Dr. Stefan Kraus, pointed both ALMA and VLT towards the triple star.

They detected warm gas at the inner edge of the misaligned ring and scattered light from the warped surface of the disk.

In their images, they saw the shadow of the inner ring on the outer disk. At the same time, ALMA allowed them to measure the precise shape of the ring that casts the shadow. Combining this information allows them to derive the 3D orientation of the misaligned ring and of the warped disk surface.

Representation of the disk structure and stellar orbit of GW Orionis, as derived from the ALMA and VLT observations by Kraus et al. Orange rings are the (misaligned) rings seen by ALMA. The transparent surfaces correspond to the lower-density dust filaments that connect the rings and that dominate the emission in scattered light. Image credit: Kraus et al / NRAO / AUI / NSF.

Using telescope arrays operating at infrared wavelengths, the researchers also mapped the orbits of the three stars for over 11 years, covering a full orbital period.

The team found that the three stars do not orbit in the same plane, but that they are misaligned with respect to each other and with respect to the disk.

Both teams also performed computer simulations to investigate what could possibly cause the inner ring to be misaligned from the rest of the disk and the stars.

Scattered light model used to determine the eccentricity and 3-dimensional orientation of the ring and geometry of the disk warp. Credit: Kraus et al., Science (2020)

Dr. Kraus and colleagues link the observed misalignments to the ‘disk-tearing effect,’ which suggests that the gravitational pull of stars in different planes can warp and break their disks.

Their simulations showed that the misalignment in the orbits of the three stars could cause the disk around them to break into distinct rings.

The simulations by Bi and colleagues hint at another possible explanation for the large misalignment between the inner and middle dust rings.


References: (1) Jiaqing Bi et al. 2020. GW Ori: Interactions between a Triple-star System and Its Circumtriple Disk in Action. ApJL 895, L18; doi: 10.3847/2041-8213/ab8eb4 (2) S. Kraus et al. 2020. A triple star system with a misaligned and warped circumstellar disk shaped by disk tearing. Science 369 (6508): 1233-1238; doi: 10.1126/science.aba4633

Sorry — Pop Music Sounds The Same Because You Want It That Way (Psychology)

Does it ever seem like pop music on the radio is all just the same song repackaged? That’s not your imagination; the large majority of radio hits are written and produced by a handful of the same people. When the variety of choices we have as consumers seems to be at an all-time high, why is pop music so monotonous? We hate to break it to you, but it’s because your brain loves the familiar — whether you like it or not.

In 1968, social psychologist Robert Zajonc asked 100 college students to look at a list of antonym pairs (things like “high/low,” “able/unable,” and “optimism/pessimism”) and asked them to choose the one in each pair that they thought had “the more favorable meaning.” He then compared their results to each word’s frequency in the English language. Overwhelmingly, the participants thought the more common word was the more favorable one. The phenomenon that makes you think more familiar things are more pleasant is known as the mere exposure effect, and it’s a big reason music producers keep pumping out the same sounds you’ve heard before.

Even at the turn of the 20th century, people knew that music sounded better the more you listened to it. In 1903, Max Meyer published a report in Experimental Studies in the Psychology of Music showing that when people heard a song that was foreign to them (in this case, quarter-tone music, like the kind common to Chinese cultures), they reported liking it more after every repetition.

Areas in the brain associated with emotion- related and reward circuitry are significantly more active for familiar music than unfamiliar music. Whether you like a song or not appears to play less of a role in generating an emotional response. Image: Pereira CS, TeixeiraJ, Figueiredo P, XavierJ, Castro SL, Brattico E (2011) Music and Emotions in the Brain: Familiarity Matters. PLOS ONE

Of course, modern technology drives this point home even more. A 2011 fMRI study found that the emotion and reward centers of the brain were more active when subjects heard familiar music than when they heard unfamiliar music, and a 2013 study found that subjects’ emotional arousal was higher after hearing a familiar song, even if the subjects didn’t remember hearing it before. You might think you’re an adventurous music fan, but your brain just loves the songs it knows.

Music producers know this all too well. According to The New Yorker, “A relatively small number of producers and top-liners [people who write the melodies and lyrics] create a disproportionately large share of contemporary hits, which may explain why so many of them sound similar.” Just take songwriter Max Martin, for example. The Swedish 40-something is responsible for a jaw-dropping number of hits, ranging from those performed by the Backstreet Boys, ‘NSync, and Britney Spears to more modern artists like Katy Perry and Taylor Swift.

The key is to mix the comfort of the familiar with a little bit of surprise. “Within the vein of all the other successful pop music, [it helps when] someone does something that’s just a little bit different,” music professor Clay Stevenson tells Pigeons & Planes. “So maybe they throw in a different instrument, maybe they throw in an extended bridge, or an extended part to their hook.”

But there’s a silver lining to all this. The fact that familiarity breeds favoritism means that with a little bit of extra work, you can easily expand your musical tastes. When you listen to something new, put it on repeat a few times. If you don’t like it after a handful of listens, well, it wasn’t meant to be. But if science has proven anything, you very well might find a new favorite.


There’s An Evolutionary Reason Why You Listen To Some Songs On Repeat (Biology)

The first time you heard Taylor Swift’s “Shake it Off,” you barely noticed. Then the song made its undercover assault, seeming to play in every grocery store, on every radio, and in every TV commercial you saw — and before you realized it, you were bobbing your head to the music. Soon, you were seeking it out, playing it over and over when no one else was around. Years later, you still can’t get enough of that Taylor Swift goodness. Never mind your questions about whether this story is autobiographical; the real question is this: What makes you want to repeat some songs over and over again while other songs go stale? The answer may lie in evolution.

Evolution favors the traits that help organisms survive to have offspring, and the best way our ancestors learned to survive was by trusting what they already knew and distrusting what they had never encountered before. If you experienced something once and it didn’t kill you, chances are it won’t kill you the second time. That may be the driver behind what psychologists call the “mere exposure effect”: basically, you like things more just by being exposed to them.

But anyone who’s had the same meal five nights in a row knows that there’s something different about repetition when it comes to music. That could be because our brains process music a lot like they process language — in other words, as if it’s information. As Bruce Richman explains in “The Origins of Music,” birds, wolves, whales, and other animals mimic each other’s calls to signal that they’re part of the group. Early humans were likely no different. At some point in our evolutionary history, those nonsense noises branched off into music and language, but the two stayed closely linked.

But even if our brains consider music to be more special than tastes or sights or even noise, why is it that some songs can send your finger toward the repeat button while others just start to get annoying? That comes back to the idea of music as information. Often, the songs we listen to over and over have a certain level of complexity — think of the decades-long popularity of Queen’s “Bohemian Rhapsody,” for example. It’s layered with so many different melodies and voices that you could listen to it five times in a row and notice something different every time. The idea is that if you can keep hearing something new with every listen, you’ll keep coming back for more.

But the opposite is also true. As parent of young children can attest, you can only listen to “The Wheels on the Bus” so many times before you want to tear your hair out. The same way your brain loves learning new things, it hates wasting time with the stuff it already knows, and simple songs get old much faster than complex ones.

But complexity is only part of it —”Shake It Off” isn’t exactly Beethoven, after all. The way the music makes you feel is also very important. In 2013, a University of Michigan study found that of the songs participants liked listening to repeatedly, more than two-thirds were happy, energetic tunes that made them “pumped up” and “ready to dance.” “Bittersweet” songs that made people feel sad and wistful were also big winners, and while not as many of those songs made the cut, the participants reported relistening to them many more times in a row than the happy songs.

It’s this emotional connection that could explain why some songs don’t get stale even after years of repeated listening. As Alex Fradera writes for BPS Research Digest, “the emotional payoff is reliable, much as is a mood-regulating drug, and that reliable payoff can be more important than the hit of something novel.” And, of course, that’s really what it all comes down to. If a song makes you feel good, you’ll want to play it again, regardless of whether it’s a complex masterpiece or fluffy pop. Haters gonna hate, hate, hate, hate, hate.


There’s An Evolutionary Reason Why Older People Get Up Early (Biology)

When it comes to age and sleeping habits, there are a lot of stereotypes. The elderly show up at the mall the minute it opens, eat dinner at 4:30, and turn in for the night before the sun even sets. Young people are out causing mischief until the wee hours and lazily sleep in ’til noon. Why is there such a sleep mismatch between the old and young? A study suggests that this bedtime quirk may have helped our ancestors survive. It’s not a bug; it’s a feature.

For a study published in Proceedings of the Royal Society B, researchers recruited volunteers from the Hadza, a hunter-gatherer society in northern Tanzania. They live in groups of 20 to 30 people, spending their days finding berries, tubers, and meat in the savanna woodlands and spending their nights sleeping outside next to the fire or indoors within woven-grass huts. Importantly, they sleep on the ground without artificial lighting or climate control, making their environment close to that of early humans.

To learn more about how early humans may have lived, scientists often turn to modern hunter-gatherer societies. Although they live in the modern world, some elements of their lifestyle have endured through the centuries. That means life in hunter-gatherer societies is often pretty similar to how researchers think our human ancestors once lived, before the advent of agriculture.

The researchers had 33 men and women between the ages of 20 and 60 to wear a sleep-tracking watch for 20 days. They found that very few of the Hadza slept at the same time. Some people, generally older participants in their 50s and 60s, went to bed as early as 8 p.m. and woke up at 6 a.m. 20- and 30-somethings, meanwhile, often stayed up until past 11 and slept in until after 8. Most participants got up a few times in the middle of the night to tend to babies or relieve themselves. Been there.

The fact that older Hadza people go to bed earlier might not be that surprising — your grandparents probably do too. But here’s the twist: Out of more than 220 hours of observation, there were only 18 minutes in the entire study where all 33 participants were asleep at the same time. On average, more than a third of the group was awake (or at least only lightly resting) at any given time.

Researchers think that this sleeping mismatch helped our ancestors survive. Predators can attack at any hour, and if a few people are always awake, someone is always around to guard against danger. Plus, you don’t need to assign people to keep watch overnight if someone’s already going to be up. Bottom line? If you’re getting older and having trouble sleeping past 7 a.m., there may not be anything wrong. It’s probably just millennia of evolution helping you watch out for lions.


There’s A Genetic Mutation That Makes People Need Less Sleep (Biology)

It’s easy to feel like there aren’t enough hours in the day, and when you need to sacrifice something, the first thing on the chopping block is usually sleep. For most of us, that makes for an unfocused, moody, miserable day. But it turns out that some people can take a few extra hours to get everything done while avoiding that all-too-familiar fogginess. That’s thanks to two rare genetic mutations that allow them to feel rested on less sleep than the rest of us.

Health experts estimate that we spend about one-third of our life sleeping, and yet the Centers for Disease Control reports that about the same proportion of American adults don’t get adequate sleep (they recommend seven hours or more per night). You might think you can get by on little sleep, but chronic or long-term sleep deprivation tends to lull you into a false sense of security. Studies show that after surviving on little sleep for a long period, people’s self-rated sleepiness tends to improve despite the fact that their performance on tasks continues to decrease. Meanwhile, their sleep habits may lead to serious health complications over the long run, including diabetes, heart disease, and high blood pressure.

But a fortunate few are able to sleep six hours or fewer without any ill effects, and in 2009, scientists at the University of California, San Francisco set out to determine how. They studied a family of “short sleepers” — people who only get four to six hours of sleep but wake up bright as a daisy — and determined their superhuman sleeplessness was due to a mutation of a gene called DEC2, which helps manage the body’s circadian rhythms.

One of the hormones that DEC2 regulates is orexin, which is involved in maintaining wakefulness. DEC2 functions as a timekeeper, lowering alertness at night by blocking orexin production but easing its grip in the morning so orexin can wake you up and keep you awake throughout the day. The DEC2 mutation in short sleepers reduces their bodies’ ability to slow orexin production, causing them to stay awake longer.

But it’s rare to find any bodily process that’s governed by a single gene. If we’re going to get a better grasp of sleep, scientists need to find the other genes at play. That’s where the team’s published their research in the journal Neuron, comes in.

To find more short-sleep genes, the scientists screened for genetic mutations in people known to be short sleepers and hit upon one particular family with a rare variant in a gene called ADRB1. ADRB1 codes for a receptor for the hormone norepinephrine, which generally controls the body’s motion and alertness. Your body pumps out norepinephrine during a “fight or flight” response, snapping your brain to attention and making your heart race. As you might imagine, norepinephrine is usually at its lowest levels during sleep.

The scientists genetically engineered mice to have this same ADRB1 mutation and found that they slept for about an hour less, on average, than non-mutant mice. When they looked at the brainstems of the mutant mice, the scientists saw that cells studded with this receptor were active when the mice were awake but quiet during their deep (non-REM) sleep. Stimulating the neurons carrying ADRB1 also immediately woke the mice from deep sleep. The team suggests that the mutation of ADRB1 makes neurons carrying the gene more active, subsequently causing the organism to be more awake and content on less sleep.

So what if you get by on little sleep? Is it possible you’re a mutant? Unfortunately, the chances that you have this sleep gene mutation are vanishingly low; the researchers estimate that it’s present in four out of every 100,000 people. Just because you’re able to wake up early and keep going after only a few hours of sleep does not mean you’re what the researchers consider to be a short sleeper.

“These are not people who’ve trained themselves to wake up early. They’re born this way,” Ying-Hui Fu, an author on both studies, said of natural short sleepers’ habits in a press release.

Several drugs can already manipulate norepinephrine receptors to treat things like psychiatric conditions, cardiovascular problems, glaucoma, and migraines. Further research on these mutations might add sleep disorders to that list, and may even produce the overachiever’s dream: adding more hours to the day by enabling the body to stay awake longer without consequence.

For now, though, you’ll need to keep making an effort to get enough shuteye and optimize your environment like banishing screens amd making your room cold, to get the best sleep possible.


Nearly Everyone Experiences Intrusive Thoughts — Here’s How To Handle Them (Psychology)

You know those dark or completely inappropriate thoughts you have? Like, what if you jumped off the bridge you’re standing on? Or you stood up and shouted in the middle of a wedding ceremony? If you’ve ever had an inexplicable urge to do something totally unacceptable to yourself or to society, then you’re not alone. In fact, “intrusive thoughts” happen in 94 percent of people with no diagnosed mental illness.

You might have heard of the “Imp of the Perverse,” which is both a nickname for intrusive thoughts and a short story by Edgar Allan Poe. In the story, a man stands looks into the abyss on the edge of a precipice and wonders what it would be like to jump off, despite knowing it would kill him. “This fall — this rushing annihilation — for the very reason that it involves that one most ghastly and loathsome of all the most ghastly and loathsome images of death and suffering which have ever presented themselves to our imagination — for this very cause do we now the most vividly desire it,” he writes. Sounds dark, but doesn’t it also sound familiar?

In a series of studies published in Behaviour Research and Therapy in 1978, two UK psychologists had 124 healthy, non-clinical subjects fill out a questionnaire on the topic. Virtually all of them said they occasionally had intrusive thoughts. This included thoughts of aggression and violence, religious blasphemy, and “unnatural” sexual acts, among other socially inappropriate or even illegal actions. And many included vulnerable parties, such as babies, the elderly, and family members. Dark stuff.

In his book “The Imp of the Mind: Exploring the Silent Epidemic of Obsessive Bad Thoughts,” psychologist Lee Baer summed up intrusive thoughts: “The Imp of the Perverse will try to torment you with thoughts of whatever it is you consider to be the most inappropriate or awful thing you could do.” He wrote that these thoughts result in one of two possible outcomes: “(1) We give the thoughts little attention and no credence and go on with our lives, or (2) we are strongly affected by the bad thoughts, so that the thoughts occur frequently during the day and interfere with our functioning socially or at work.”

While we all experience them, intrusive thoughts can become especially hard to cope with in patients suffering from obsessive-compulsive disorder (OCD) or attention-deficit hyperactivity disorder (ADHD). Postpartum depression can also trigger intrusive thoughts in new mothers: A 2006 study of 89 new parents found that nearly 90 percent of them experienced intrusive images of their newborns being harmed.

Science hasn’t figured out exactly why we have intrusive thoughts, but researchers have at least found ways to cope with them when they start to seriously drag you down. Similar to OCD treatments, exposure and response prevention therapy can help. Patients can also learn to identify and control these thoughts using cognitive behavioral therapy in mild cases, though drugs are sometimes prescribed in more severe cases where therapy is ineffective.

If you’re looking for a few tips to start managing your own intrusive thoughts, then start by accepting them. According to Northpoint Recovery, running away “never works.” Sometimes, the very fear of having these thoughts is what might trigger them, akin to how being told not to think of an elephant leads you to think of only that. Don’t be afraid of your intrusive thoughts or take them personally, but be mindful and accept that you have them. It’s also helpful to remember that these thoughts have nothing to do with your reality. We pretty much all have them, after all — the only thing that really matters is how you respond to them.


Reactance Is Why You Act Irrationally When Your Freedom Is Threatened (Psychology)

Teenagers don’t exactly love being grounded. They tend to yell, or storm off, or sneak out to parties anyway. This is less because they’re young, it turns out, than because it’s human nature. When we sense our freedoms are under threat, we all tend to act out, sometimes irrationally, to reestablish our sense that we’re free. Psychologists call this “reactance.”

WHAT IS REACTANCE?

Psychologist John Brehm first proposed the concept of reactance in 1966. At the time, psychology as a field was very interested in how persuasion worked. Brehm, however, was more interested in how persuasion failed, though, and reactance was often a factor. If someone feels like you’re bossing them around, it triggers reactance, and they’re unlikely to see your perspective.

In fact, people often do the diametric opposite of what “bossy” figures tell them to. In one study, a judge warned a mock jury to disregard inadmissible evidence, with no further explanation. While another jury that had simply been told certain evidence was inadmissible ignored that evidence in their deliberations, the jury that was admonished by the judge felt their freedom to interpret it themselves was under threat — and they used the evidence to make their final decision, in spite of the judge’s directions.

You don’t need to be a judge to provoke reactance, though — far from it. Most things we consider “bad news” can be viewed as a loss of freedom. Injuries and illnesses restrict your physical freedom. Getting dumped means you lose your freedom to see your partner when you want, and your freedom to choose if and when the relationship ends. Being fired is a similar double whammy.

Most of this “bad news” is really just sudden change, which can be framed as an opportunity. Getting dumped, for instance, can be viewed as an opportunity to meet new people. But when people lash out in response to change, it’s usually because they perceive their freedom to be dwindling. This triggers reactance, a psychological phenomenon, but that, in turn, triggers a burst of adrenaline. Something akin to the fight-or-flight instinct kicks in. People feel compelled to do something, even if it’s stupid or counterproductive.

WHY DOES REACTANCE MATTER?

Interestingly, though reactance can manifest explosively and even violently, it also explains a lot of indecision and inaction. In a 1970 study, participants had to choose between two different styles of interview. One style wasn’t obviously better than the other. People tended to put off making the choice at all because they felt most free with two attractive options in front of them. Choosing one would be exercising freedom, but it would also feel like a loss of freedom. (Exhibit A: every love triangle on TV.)

One thing reactance doesn’t mean is that humans inherently dislike rules and constraints, though. We do like some limits. In fact, too much choice can make us unhappy. In one study, people shopped at a display of either six or 24 jams. Those with fewer choices were more likely to buy jam, and more likely to feel good about their selection. Still, other studies have shown that you’re more likely to buy a product with two options than you are if there’s only one. What triggers reactance is not that our freedom is limited, but that freedoms we already have feel like they’re slipping away. It’s a key distinction.

So what do you do with this situation? When you know reactance is possible, you can figure out an optimal way to deliver bad news without triggering the feeling. It’s best if it comes with a built-in choice, so the recipient feels some freedom — we’re breaking up, but you decide how we divvy up the furniture! — and an immediate, constructive activity that will soak up some adrenaline — you’re getting demoted, and can you walk down to HR to pick up some paperwork? By granting the illusion of freedom and providing an active distraction, you can help keep lashing out to a minimum.


Why You Unconsciously Copy Other People’s Mannerisms (Psychology)

Humans aren’t as different from chameleons as you’d think. Sure, we’re not lizards, and we don’t turn green every time we go in the yard, but we have our own tricks for blending in. Research suggests that in social situations, we tend to unconsciously imitate the people around us in a phenomenon researchers have termed the chameleon effect.

In 1999, New York University researchers Tanya Chartrand and John Bargh detailed three experiments that roughly mapped out how the chameleon effect works. In the first, each of the participants worked with a partner — secretly an actor — on a task in which they took turns describing photos. When the actor smiled, maintained a neutral expression, jiggled his or her foot, or rubbed his or her face, the participant tended to follow suit. This seemed to be unconscious: In exit interviews, most people said they hadn’t noticed their partner’s mannerisms, and none of them remarked on the mannerisms being studied (smiling, foot-jiggling, face-rubbing).

Though it was unconscious, this mimicry improved rapport between strangers, the team found in a second experiment. Here, participants were partnered with undercover actors again. This time, though, the actors either mimicked the participants’ behaviors or adopted “neutral mannerisms.” Participants whose partners had mimicked them were significantly more likely to say they liked their partners and that the interaction had gone smoothly than those whose partners remained neutral.

Not everyone is equally prone to mimicking the people around them, though. In the third experiment of the study, the team first measured people’s empathy using Davis’s Interpersonal Reactivity Index, which tests how likely you are to spontaneously try on another person’s perspective. They found that the more empathetic someone was, the more likely they were to mimic their partner’s mannerisms. This makes sense, the team argued, because empathetic people pay more attention to the people around them and have an overall greater perception of those people. Perception is important here.

The mechanism behind the chameleon effect, researchers argue, is the perception-behavior link. This is the phenomenon where just by witnessing someone doing something, you become more likely to do it, too. This link is well documented when it comes to micro-level behaviors you can mimic unconsciously: gestures, postures, speech patterns, moods, etc. If you watch someone run a record-setting mile, though, it’s unlikely you’ll just stand up and imitate them.

In other words, it’s not just yawning that’s contagious — it’s pretty much every move we make in front of another person. “Contagious” might sound alarming, but in this case, it’s a good thing. Mimicry seems to work like a social glue, helping pairs to bond and promoting group cohesion. And as the researchers behind this study pointed out, it seems to help us bond even when we’re not trying to. After all, they got their results from pairs of strangers interacting in 10- to 15-minute windows with no particular incentives to collaborate.

It’s almost like the perception-behavior link, and the chameleon effect specifically, is a lucky charm that’s with you wherever you go, making all your interactions more pleasant — even your fleeting interactions with strangers. In fact, it might be most important with strangers, who have to guess your character based on surface signals like body language. The next time you find yourself mirroring someone’s gestures or mimicking someone’s accent, don’t be embarrassed — just remind yourself that it means you’re an empathetic human being.