By Ellyn Lapointe Published May 21, 2025 | Comments (0) | A young male white-faced capuchin carries a baby howler monkey on its back, captured by a remote camera trap on Jicarón Island © Brendan Barrett / Max Planck Institute of Animal Behavior A young male capuchin named Joker may just be the world’s first primate influencer. But the trend he started—abducting babies belonging to a separate species—has deadly consequences. Joker is one of many white-faced capuchins living on Jicarón Island off the coast of Panama. Researchers had been using cameras to observe the behavior of these round-headed, stocky monkeys when, in 2022, something unusual caught the eye of Zoë Goldsborough, a doctoral researcher at the Max Planck Institute and a research associate at the Smithsonian Tropical Research Institute in Panama.  She was scrolling through camera-trap footage when she spotted a male capuchin carrying a baby monkey on its back. This was already an unusual sight—female primates are almost always the ones to carry the young. But upon closer inspection, it got even stranger. “I really quickly saw that the coloration was completely wrong,” Goldsborough told Gizmodo. “The capuchin monkeys have dark fur and light face, and this [baby] had lighter fur and a dark face.” The only other primates on the island are howler monkeys, and this infant’s coloration matched that species, she explained. “So it was really quickly clear that it could only be a howler monkey, but that just made no sense whatsoever.” This sighting inspired Goldsborough to sift through tens of thousands of images captured by all cameras deployed around the same time period, according to a statement from the Max Planck Institute. She found four different instances of the same capuchin, a male who she named Joker, carrying baby howler monkeys. “With everything we found, we had more answers, but also more questions,” Goldsborough said.  At first, she and her colleagues thought this behavior could be a form of adoption—when an animal assumes a parental role for an infant of another species. It’s relatively common among primates, but almost exclusively carried out by females who presumably do it to practice caring for young, according to the Max Planck Institute. So what was motivating Joker—a male—to kidnap these baby howlers? Before Goldsborough and her colleagues could begin to answer that question, new ones arose. They discovered video and images of four more young male capuchins carrying baby howlers, five months after Joker started doing it. They were copying him—it was a real-world case of “monkey see, monkey do.” The researchers’ study, published Monday in the journal Current Biology, details how the trend-setting Joker and his four followers carried 11 different howler infants over the course of 15 months. The babies clung to their backs or bellies as the capuchins went about their business, sticking together for up to nine days at a time. Aside from some occasional annoyance when the infants tried and failed to nurse, Goldsborough said the capuchins were gentle with their strange passengers—Joker especially. “He seems to be really interested in having these infants and carrying them for long periods of time,” she said.  But because these males could not produce milk, the infants didn’t fare well with their adoptive fathers. The researchers saw four babies die from apparent malnourishment, and suspect the others perished as well. In three cases, the capuchins continued to carry their dead infant for at least a day after it had passed. Based on their findings, the researchers determined that this was a case of interspecies abduction, not adoption. It’s not yet clear why the capuchins picked up this trend, as it is rare for primates to kidnap the young of other species, but it’s not uncommon for one individual’s behavior to spread to other members of the population through social learning. As for why Joker initiated the behavior in the first place, Goldsborough says there are a few possible motivations. His remarkably gentle interactions with the howler babies suggest he may have had some sort of caring motivation, she explained. “I think it’s possible that there was something a little quirky about him, or that he was kind of lonely in a way,” she said.  To get to the root of his behavior, Goldsborough wants to learn more about his social position. Determining whether Joker is a leader or a loner could provide further insights into how social learning manifests in primate groups, she said. Daily Newsletter You May Also Like By Ed Cara Published May 15, 2025 By Isaac Schultz Published May 6, 2025 By Isaac Schultz Published May 5, 2025 By Ed Cara Published April 25, 2025 By George Dvorsky Published March 21, 2025 By Ed Cara Published February 28, 2025

A male white-faced capuchin monkey carrying a baby howler monkeyBrendan Barrett/Max Planck Institute of Animal Behavior Capuchin monkeys on a remote Panamanian island are abducting babies from howler monkey families, in a first-of-its-kind trend. The wild population of white-faced capuchins (Cebus capucinus imitator) living on Jicarón Island has been monitored with 86 motion cameras since 2017 to capture their sophisticated use of stone tools to crack open hard fruits, nuts and shellfish. Five years into recording the footage, in 2022, a researcher noticed one of the young male capuchin monkeys with an infant monkey from another species clinging to its back. This capuchin, nicknamed Joker, picked up at least four baby howler monkeys (Alouatta palliata coibensis) over four months, sometimes holding onto them for more than a week. Advertisement At first, the researchers thought it was a case of “one individual who maybe is a little weird or a little quirky”, says Zoë Goldsborough from the Max Planck Institute of Animal Behavior, who spotted the behaviour. “We didn’t expect to find this.” Then, five months after they saw Joker with an infant, four other young male capuchins were found carrying around howler babies. Over 15 months, the capuchin group took in 11 howler babies younger than four weeks old. The behaviour spread around the population through social learning, like a “primate fad or fashion”, says Andrew Whiten at the University of St Andrews, UK, who wasn’t involved in the study. Unmissable news about our planet delivered straight to your inbox every month. Sign up to newsletter While mature female monkeys sometimes adopt abandoned babies of other species, which may be a way to practise caring for their young, the Jicaròn monkeys doing this are all immature males. And instead of adopting abandoned infants, they seem to be actively taking the howlers from their families. There is no footage of the thefts, but they did document capuchins preventing the howler babies from escaping. Footage also shows howler monkey parents searching and calling for their infants in the canopy as the capuchins get defensive. The abducted infants probably all die from malnourishment, since they are too young to survive without their mother’s milk. Researchers saw at least three howler monkey infants being carried around even when dead. Two white-faced capuchins with a baby howler monkeyBrendan Barrett / Max Planck Institute of Animal Behavior Learning from others can be beneficial, which is why a trend can take off even when the behaviour has no real benefits to the monkeys, says Whiten. Since the Jicarón capuchins have no predators and very little competition, the craze could have arisen as a result of having spare time to try new things, and possibly out of boredom. There might also be something about the conditions of life on a remote island that are conducive to innovative behaviours arising and being spread. It is these same young male monkeys who most use tools on Jicarón, notes Goldsborough. “Maybe if you have a tradition already, you’re more likely to also copy their other behaviours.” Topics:

This list contains spoilers for the Mission: Impossible franchise.A new Mission: Impossible film is hitting theaters this month – the final one in the franchise, if we’re to believe Tom Cruise and the suits at Paramount – and if you’re like us, you’re probably knee deep in a series rewatch right now.The focus of the films, spectacular action set pieces aside, has been Cruise’s lead spy, Ethan Hunt. Fellow team agents have often come and gone, and supposedly impossible missions have varied time after time, but Ethan has remained. The only other constant has been a steady supply of villains – men and women with big plans fueled by greed and/or malice, who think they’ll be the one to outwit, outsmart, and outrun Hunt. Fools.It might seem counterintuitive ranking the Mission: Impossible villains under the banner of “best,” but every great hero needs an equally great villain. Numerous elements come into play when determining the best villain, but we’re zeroing in on the scale of their threat, the weight of the violence (both physical and emotional) they commit against Hunt and his team, and the palpable degree of villainous charisma they exhibit.So cue up that classic Lalo Schifrin theme, here are the 10 Best Mission: Impossible Villains, Ranked!Top 10 Mission Impossible Villains10. A.I. The Entity (Mission: Impossible - Dead Reckoning Part One)Director: Christopher McQuarrie | Writer: Christopher McQuarrie and Erik Jendresen | Stars: Tom Cruise, Hayley Atwell, Ving Rhames, Simon Pegg, Rebecca Ferguson | Release Date: July 12, 2023 | Runtime: 163 mins“A self-aware, self-learning, truth-eating digital parasite infesting all of cyberspace” sounds like a pretty cool threat in any other high-octane thriller, but in the Mission: Impossible franchise it’s only good enough to land at number ten. It underwhelms compared to its human counterparts, because let’s be real – zeroes and ones ain’t got shit and madness and guns – but its power and immense reach are undeniable. The Entity began “life” as a digital weapon designed by the U.S. government before going rogue and hopping through cyberspace with the giddiness of a puppy experiencing its first snowfall.Most villainous act of villainy: While toying with and killing a submarine filled with Russian sailors is an act of murderous cruelty, it’s the Entity’s bigger, broader acts of deception that mark it as a true villain. Its early days of online manipulation saw it shifting public opinion and behavior through social media, and it’s a brutal reminder of events in the real world. We live in a present where people with nefarious agendas are influencing easily shaped minds, and with the increased use of A.I. in our online dealings, it’s not hard to imagine something like the Entity stepping in and really turning our daily lives into a nightmare.Where to WatchPowered by9. John Musgrave (Mission: Impossible III)Director: J.J. Abrams | Writer: Alex Kurtzman, Robert Orci, and J.J. Abrams | Stars: Tom Cruise, Philip Seymour Hoffman, Ving Rhames, Billy Crudup, Michelle Monaghan | Release Date: May 5, 2006 | Runtime: 126 minsNot every villain has direct blood on his hands, but that doesn’t mean they’re any less dangerous. Musgrave is Hunt’s Operations Manager at the IMF, and it’s suggested they may even be minor friends – understandable as he’s played by Billy Crudup, and who wouldn’t want to be friends with Billy Crudup. He brings Hunt in on a mission to rescue one of his proteges, Lindsey Farris, and when that goes wrong and Hunt is blamed for the fallout, it’s Musgrave who helps the agent escape to pursue justice. See? A friend.Surprise! It’s all a ruse, and Musgrave is actually a traitor working with a man named Owen Davian on some elaborate plan to retrieve a piece of tech nicknamed “the rabbit’s foot.” Musgrave’s a hero in his own mind, though, as he’s hoping to use this as motivation for first strikes against enemy forces. He wants the U.S. and the IMF to play a more aggressive role in the fight against terrorism, and if that means supporting terrorists along the way, well, he’s all for it.Most villainous act of villainy: Musgrave might think his heart is in the right place here, but in addition to enabling a murderous terrorist in Davian, he crosses an equally big line by pulling Ethan’s wife, Julia, into danger. Worse, he lets Davian shoot Julia in the head right in front of Hunt. Sure, she’s revealed to have been a minor henchwoman in a mask, but the emotional damage is real.Mission: Impossible IIIParamount PicturesMay 5, 2006PG-13Where to WatchPowered by8. Kurt Hendricks (Mission: Impossible - Ghost Protocol)Director: Brad Bird | Writer: Josh Applebaum and Andre Nemec | Stars: Tom Cruise, Paula Patton, Simon Pegg, Jeremy Renner, Michael Nyqvist | Release Date: December 21, 2011 | Runtime: 132 minsWhile some villains act out of greed and others cause misery simply for the fun of it, Kurt Hendricks is a man who only wants the best for humanity. What is the best, you ask? Well, in Hendricks’ mind, our species would benefit from something of a cleanse. From the great biblical flood to the atomic bombing of Japanese cities during World War II, immense disasters lead to rebuilding, recovery, and real improvement… apparently.Sounds logical, so Hendricks sets out to trigger just such a global debacle starting with a massive attack on the Kremlin in Moscow and leading to the acquisition of nuclear codes. He proves himself to be one of the greatest threats Ethan Hunt has faced to that point.Except, and this is where casting comes into serious play, the film wants us to see him as a physical threat to Hunt – but that’s nearly impossible. Michael Nyqvist was a fantastic actor, and he makes for a compelling villain through dialogue and intent. But a serious contender in a fight with Cruise? It’s difficult to buy, but that doesn’t stop director Brad Bird from letting him go toe to toe with the film’s star for a weirdly long fight. (To be fair, Chad Stahelski started it by letting Nyqvist seemingly hold his own for a bit with Keanu Reeves in John Wick.) So, while Hendricks is a grand threat on the world stage, he tumbles some in the ranking here as an unserious brawler against the highly trained and in far better shape Hunt. Most villainous act of villainy: Like Musgrave above, Hendricks seriously thinks he’s doing the world a favor by causing harm. His final act results in a nuclear missile being fired towards San Francisco, something that would have killed tens of thousands of people immediately before triggering the death of millions more. That’s no small thing, and he would have gotten away with it, too, if it hadn’t been for those meddling IMF agents.Where to WatchPowered by7. August Walker (Mission: Impossible - Fallout)Director: Christopher McQuarrie | Writer: Christopher McQuarrie and Erik Jendresen | Stars: Tom Cruise, Henry Cavill, Ving Rhames, Simon Pegg, Rebecca Ferguson | Release Date: July 27, 2018 | Runtime: 147 minsHunt and his IMF team have been betrayed by double agents and traitors on numerous occasions, but most of them are greedy middle-aged men in suits who don’t pose an immediate physical threat to our intrepid hero. August Walker is something different entirely. He towers over Hunt and is jacked from his mustache on down. Henry Cavill’s portrayal ensures that he’s already menacing even while pretending to be on Hunt’s side, but once the truth comes out, the gloves come off.Walker is revealed to be working in cahoots with the brilliant Solomon Lane, and together they frame Hunt and once again pull the love of his life, Julia, into harm’s way. His motivation for it all is a bit over the top and dramatic – he wants the old world to implode and give rise to something better – but what else would you expect from a man who seems to cock his arms like guns during fist fights.Most villainous act of villainy: Walker and Lane are planning to detonate nuclear bombs, and while the latter stays behind to die in his greatest act of terror, Walker is on a chopper heading to safety. Hunt, of course, catches up to him in pursuit of the detonator that’s needed to stop the countdown. While Walker could have easily escaped by giving up the detonator, his desire to cause suffering – especially Hunt’s suffering if Julia were to die – leads him to a one-on-one fight to the death with the agent. It’s a decision built on rage and self-righteous justification, and it rightfully ends in his painful demise.Mission: Impossible - FalloutParamount PicturesJul 27, 2018Where to WatchPowered by6. Paris (Mission: Impossible - Dead Reckoning Part One)Director: Christopher McQuarrie | Writer: Christopher McQuarrie and Erik Jendresen | Stars: Tom Cruise, Hayley Atwell, Ving Rhames, Simon Pegg, Rebecca Ferguson | Release Date: July 12, 2023 | Runtime: 163 minsWhen it comes to villains in the Mission: Impossible universe, few can touch Pom Klementieff’s Paris on style and charisma points. A henchwoman to Gabriel, she lets her gleefully murderous skillset do most of her talking, and it’s a refreshing change of pace from baddies who seem compelled to share their life stories before pulling a trigger.Her costume and face makeup see her stand apart from the crowd, but don’t let her doll-like appearance fool you. Paris is a merciless fighter who refuses to quit despite the odds, as evidenced by a shootout and car chase in Rome that sees her literally plowing through obstacles both human and otherwise in her pursuit of Hunt. Most villainous act of villainy: While Paris makes mincemeat out of numerous threats, she ultimately succumbs to Hunt during an alleyway brawl. He spares her life, though, and after being punished by Gabriel – he basically tries to kill her – she chooses to betray both him and her villainous tendencies by saving Hunt’s life. Maybe I’m stretching the definition here, but it takes a real badass to turn your back on villainy with the discovery of unexpected morals and a change of heart.Where to WatchPowered by5. Gabriel (Mission: Impossible - The Final Reckoning)Director: Christopher McQuarrie | Writer: Christopher McQuarrie and Erik Jendresen | Stars: Tom Cruise, Hayley Atwell, Ving Rhames, Simon Pegg, Rebecca Ferguson | Release Date: July 12, 2023 & May 23, 2025 | Runtime: 163 mins & 169 minsThe mysterious Gabriel arrives in the penultimate entry of the franchise, and he’s a man with deadly skills and an alliance with the Entity. He also comes with a backstory suggesting an integral role in Ethan Hunt’s life. It seems Gabriel killed a woman named Marie thirty years ago, someone Hunt was apparently fond of, and it’s that murder that landed Hunt at the IMF – where he went on to save thousands of lives. Hundreds of thousands, even. So maybe Gabriel is a hero? I kid, I kid.He’s obviously a villain, and he may even be something of a seer (?), but while his late-to-the-party franchise arrival unavoidably undercuts his dramatic weight, the character’s casting lifts Gabriel right back up again. Esai Morales brings real charm and a calm menace to the character, and it’s immediately made clear that he’s not someone to be trifled with. You believe both his physical abilities and deadly intentions, and Morales’ added dramatic weight makes him a real threat to Hunt. He also earns a bump in the rankings by gifting viewers with the best, most unforgettable villain death in the entire franchise.Most villainous act of villainy: Gabriel’s killed a lot of people, and he even destroyed a rolling Agatha Christie landmark, so it’s clear he’s a bad guy. His most vicious act, though, comes as a bookend to having “fridged” Marie three decades earlier. Gabriel threatens to do it again by killing either Ilsa or Grace – Hunt’s current love interest or the woman who just landed in his lap mere hours ago – and while the film wants to trick viewers into thinking it’s going to be the latter, it’s Ilsa who dies by Gabriel’s blade instead. McQuarrie and Cruise are obviously the real villains here for introducing this tired trope of a woman’s death being responsible for a man’s life, but it’s ultimately Gabriel who thrusts the knife into Ilsa’s gut. It could have been Grace who died. Hell, it should have been Benji. Instead, Gabriel extinguishes the franchise’s brightest flame this side of Hunt himself. J’accuse!Where to WatchPowered byNot yet available for streaming.4. Jim Phelps (Mission: Impossible)Director: Brian De Palma | Writer: David KoeppSteven Zaillian, and Robert Towne | Stars: Tom Cruise, Jon Voight, Emmanuelle Beart, Henry Czerny, Jean Reno | Release Date: May 22, 1996 | Runtime: 110 minsJim Phelps wasn’t the only friend/fellow agent to betray Hunt over the years, but he was the first – and arguably the most shocking. The character, as played by Peter Graves, was the IMF’s lead agent for the bulk of the television series’ seven-season run from 1966 to 1973. He was unquestionably a good guy, so there was no reason to suspect that his presence in the first Mission: Impossible film would be anything different – well, Jon Voight in the role was probably a clue.Audiences expected Phelps to essentially hand the reins over to Tom Cruise’s Ethan Hunt, but while he did just that, he did so with a major act of betrayal. As he tells Hunt once his ruse is discovered, the end of the Cold War threatens to end the need for the IMF – this is as naive a statement as ever uttered in the entirety of the franchise – and he was worried about becoming a relic barely scraping by on sixty-two thousand dollars a year.Most villainous act of villainy: The betrayal itself is already brutal as Phelps turns his back on friends and agents who’ve risked their lives together over the years, but it’s the specifics of his traitorous act that hits hardest. In his effort to frame someone else for his crime, Phelps kills off three members of his team during an operation and then fakes his own death. What could have been a simple theft, instead becomes an act of cruelty making his betrayal sting even more.Where to WatchPowered by3. Sean Ambrose (Mission: Impossible II)Director: John Woo | Writer: Robert Towne | Stars: Tom Cruise, Dougray Scott, Thandiwe Newton, Ving Rhames | Release Date: May 24, 2000 | Runtime: 123 mins“That was always the hardest part of having to portray you,” says ex-IMF agent Sean Ambrose to a beaten and angered Ethan Hunt, “grinning like an idiot every fifteen minutes.” That line alone makes Ambrose a top villain as it’s a terrific zing at both Hunt and Cruise himself. He’s equally dismissive of women as evidenced by his comment that they’re like monkeys when it comes to the men in their lives, that they “won’t let go of one branch until they get a grip on the next.” Say what you will about his greedy desires, but Ambrose (Dougray Scott) understands the assignment when it comes to being a charismatic villain.That greed has led him to steal a deadly plague with plans to unleash it on whole populations if his demands aren’t met. While cash money is his primary motivator, though, Ambrose also seems fueled by a splash of jealousy towards Hunt. That makes their faceoffs all the more entertaining whether they’re jousting on motorcycles or sharing beatdowns in the sand as only the great John Woo can capture it.Most villainous act of villainy: The film opens with Ambrose masquerading as Hunt in order to acquire the Chimera plague, but rather than just kill one man, Ambrose and his team crash an entire passenger jet filled with innocent civilians. Acts of terror would claim higher body counts in later films, but this puts faces to the dead in a far more direct way making it more personal and affecting.Mission: Impossible IIParamount PicturesMay 24, 2000PG-13Where to WatchPowered by2. Solomon Lane (Mission: Impossible - Rogue Nation)Director: Christopher McQuarrie | Writer: Christopher McQuarrie | Stars: Tom Cruise, Simon Pegg, Rebecca Ferguson, Ving Rhames, Sean Harris | Release Date: July 31, 2015 & July 27, 2018 | Runtime: 131 mins & 147 minsWhether due to low pay or poor benefits, the world is seemingly overflowing with ex-government employees ready and willing to betray their nations and jump on the train to villain town. Solomon Lane is one such agent, but he goes a step or three further by helping create an organization called The Syndicate that’s built entirely on those bitter, trigger happy ex-agents. They want to sow chaos and reap financial rewards, and they’ve been doing it for years.Lane is introduced killing a young, unarmed female agent right in front of Hunt, and it’s soon revealed that he’s responsible for thousands of deaths over the years through events made to look like accidents or the work of wholly unrelated perpetrators. Lane’s history of manipulating trust and the world’s various systems makes him one of the most dangerous villains in the franchise. He’s ahead of Hunt at every step, and his mantra – “The greater the suffering, the greater the peace.” – marks him as a man willing to do anything to accomplish his goals.While many actors go big playing villains, Sean Harris takes the opposite approach and makes Lane a weasel of a man who you just want to see get beaten senseless. It’s an unusually bold choice that leaves him without a darkly appealing persona or personality – he’s just a very bad man who couldn’t care less about you or your loved ones.Most villainous act of villainy: As the rare villain to be an active threat across more than one film, Lane inflicts plenty of pain, suffering, and stress on Hunt and his team. The bulk of his evil acts were committed before Mission: Impossible - Rogue Nation even begins, but his cruelest and most personal action unfolds during the followup, Fallout. Along with August Walker, Lane manages to activate two nuclear bombs threatening not only the water supply for billions of people, but also the life of Hunt’s greatest love, Julia. Seeing her in harm’s way is the kind of gut punch that Hunt felt only once before, and it’s clear just how sorry he is that his choices have once again brought her so close to dying.Where to WatchPowered by1. Owen Davian (Mission: Impossible III)Director: J.J. Abrams | Writer: Alex Kurtzman, Robert Orci, and J.J. Abrams | Stars: Tom Cruise, Philip Seymour Hoffman, Ving Rhames, Billy Crudup, Michelle Monaghan | Release Date: May 5, 2006 | Runtime: 126 minsThere’s a lot of competition when it comes to selecting the best villain in the Mission: Impossible franchise, but there was never any doubt who’d land at the top of the heap. Davian doesn’t care about much beyond his own wants and needs, and the film reflects that by never revealing exactly what his end goal is – we know he wants the so-called rabbit’s foot, but what it is and what it does are never made clear. We just know that Davian will cut through anyone and anything to get it, and that makes him an exceptionally dangerous man.J.J. Abrams’ Mission: Impossible III is unfairly maligned, but even those underwhelmed by the film itself can’t help but applaud Philip Seymour Hall’s frighteningly effective and highly entertaining portrayal of Davian. His blistering stares, his lightning quick shifts from dead silence to raging outbursts, and his deceptively calm way of threatening everything that Hunt holds dear all work to make him a villain who commands the screen and even steals every scene from Cruise himself.There may not be a big, global threat at play here, but Davian is the man who arguably gets closer than any other villain to actually killing Hunt. He injects the agent’s head with an explosive device that gets within seconds of churning Hunt’s brain tissue into ground beef, and he even gets some serious licks in while brawling. You wouldn’t think a Cruise versus Hoffman fight would convince, but the latter’s pure ferocity paired with Hunt’s incapacitation due to the pain in his head makes for a viciously compelling bout.Most villainous act of villainy: Davian is a mean bastard who, while still in restraints, coldly threatens to murder Hunt’s fiance Julia. “I’m gonna make her bleed and cry and call out your name”, he says, and it’s one of the few times where Hunt’s legendary control tips into real fear and emotion. Davian later comes close to doing just that after abducting Julia, tying her up, and appearing to shoot her in the head. Hunt’s pain is palpable, and it’s enough to damage his heart to the point that he’d go on to never let someone that close again. Davian has literally halted Hunt’s ability to connect with someone on a deeply personal level, and it’s the kind of attack that bullets and bombs just can’t compete with.Mission: Impossible IIIParamount PicturesMay 5, 2006PG-13Where to WatchPowered by

Young male capuchins have developed a strange trend of acquiring baby howler monkeys. It doesn't end well for the babies.

News Animals Juvenile capuchins are kidnapping infants of another monkey species Among primates, spending time with infants from another species is very rare Capuchins are highly intelligent primates with a penchant for quirky behavior. Their latest gaff? Kidnapping endangered infant howlers. Niki Harry/Getty Images By Freda Kreier 1 hour ago There’s a serious case of stranger danger unfolding on an island off the coast of Panama. A gang of five juvenile capuchin monkeys living on Jicarón Island has started abducting baby howler monkeys, researchers report May 19 in Current Biology. This bizarre fad, which has no clear purpose, is often deadly for abductees. Capuchins “do such interesting, weird, quirky and sometimes dark things,” says Brendan Barrett, an evolutionary behavioral ecologist at the Max Planck Institute of Animal Behavior in Konstanz, Germany. These behaviors “can offer a dark window of reflections into what we do.” Sign up for our newsletter We summarize the week's scientific breakthroughs every Thursday.

Capuchin Monkeys Caught on Camera ‘Abducting’ Baby Howler Monkeys in a Strange Tradition Seen for the First Time Scientists on Panama’s Jicarón Island were mystified by photos and videos of young male capuchins carrying howler monkeys on their backs for days at a time Lillian Ali - Staff Contributor May 19, 2025 11:00 a.m. A howler monkey infant, only a few days old, clings to a subadult white-faced capuchin monkey as it uses tools. Brendan Barrett / Max Planck Institute of Animal Behavior In June 2022, while watching footage from an island off the western Pacific coast of Panama, researchers spotted a strange wildlife behavior they’d never seen before. A young, male capuchin monkey walked past the camera with a baby howler monkey clinging to its back. “What am I looking at here?” Meg Crofoot, an ecologist at the Max Planck Institute of Animal Behavior and one of the researchers observing these capuchins, tells Smithsonian magazine about the first time she saw the footage. “It’s so weird.” As they played back more of the recorded videos, the scientists realized they were observing a new social tradition among young male capuchins: abducting baby howler monkeys. The kidnapped howlers were all less than four weeks old, and in some videos taken by the research team, adult howler monkeys can be seen or heard calling out for the missing babies. While the male capuchins did not directly hurt the babies, they could not provide milk to them, and several howlers died of malnourishment, the research team reports in a study published today in the journal Current Biology. Capuchin monkeys are abducting baby howlers. But why? Watch on The research started on Panama’s Jicarón Island in 2017, when scientists obtained enough funding to set up a project there. They placed camera traps, which took photos or videos when they detected motion, and discovered the island’s white-faced capuchin monkeys regularly use stone tools. That marked the first known population of tool-using capuchins. But after several years of monitoring the monkeys, Max Planck Institute of Animal Behavior researcher Zoë Goldsborough observed the new behavior from the group, spotting the first instance of a young male capuchin carrying around a baby howler monkey. “This has never been observed anywhere else, not on this island, or in any other populations of capuchin monkeys,” Goldsborough says in a statement from the Max Planck Institute of Animal Behavior, which, along with the Smithsonian Tropical Research Institute (STRI), funded the research. Because the researchers used motion-sensing cameras, they could easily jump back and forth in time to look for new sightings and retroactively check if they missed old ones. They traced the first instances of this behavior to one monkey, who they nicknamed “Joker,” initially seen carrying a howler infant in January 2022. But at the start, Joker’s antics didn’t seem to catch on. A howler infant carried on the back of Joker, the first capuchin to "innovate" the carrying tradition. A juvenile capuchin looks at them from the side. Brendan Barrett / Max Planck Institute of Animal Behavior Five months after the first sighting, however, researchers saw even more capuchins seemingly copying Joker and carrying howlers. Over 15 months of footage, they observed 11 infant howlers carried by young capuchins, each for up to nine days at a time. While Joker “paid more attention to the babies that he carries,” and was generally more interactive, the capuchins that later adopted the behaviors “really don’t interact with the babies,” says Crofoot, who, along with Goldsborough, is also a research associate at STRI.  Researchers do not know how the capuchins got the howlers in the first place. Howler monkeys primarily live in trees, so Crofoot assumes that is where the capuchins found them. Why capuchins appear to be abducting baby howlers is still unclear, but the team examined multiple possibilities. Since howlers and capuchins have different diets, the researchers ruled out competition for food. They also did not see the “carrier” capuchins getting positive social attention from their peers, though sometimes one capuchin would lose interest in the howler he was carrying and drop it for another capuchin to scoop up. The team’s suggestion? Boredom. Life on Jicarón Island has few competitors and no predators for the capuchin monkeys. This low-stress and potentially under-stimulating environment might lead the monkeys to create new behaviors, the researchers say. “Capuchins appear to carry howler infants solely for carrying’s sake,” they write in the paper. A white-faced capuchin monkey uses stone tools at a streambed while carrying a baby howler on its back. Brendan Barrett / Max Planck Institute of Animal Behavior Susan Perry, a primatologist at the University of California, Los Angeles, who has studied social behaviors among capuchins and was not affiliated with this research, suggests the carrying behavior stems from capuchin males wanting to alloparent other infants, or take care of babies that are not their own offspring. “Male capuchins frequently steal capuchin infants,” Perry writes in an email to Smithsonian magazine. “I think this is because they are trying to develop relationships with infants that are going to be their sidekicks/henchmen when they immigrate.” Georgia State University primatologist Sarah Brosnan, who was also unaffiliated with the research, compares the behavior to the use of a “toy,” especially because it was primarily observed among juvenile and immature capuchins. “These are juveniles,” Brosnan says. “I don’t think that they are grabbing [howlers] because they’re kidnapping, I think they’re grabbing it because it’s an interesting and engaging toy. It makes noise, it moves.” This isn’t the first time a hard-to-explain social tradition has been recorded in capuchin monkeys. More than 20 years ago, Perry observed capuchin groups demonstrating social behaviors, like “hand-sniffing,” when one capuchin sticks a finger up another’s nose for several minutes, and turn-taking “games,” such as when monkeys try to retrieve objects hidden in each other’s mouths. “It suggests that capuchins are really, really interested in these social traditions—really strongly socially motivated—and easily developed these social traditions,” Brosnan adds. To Crofoot, the findings show that humans are not alone in having “arbitrary” social traditions, born from boredom-fueled innovation. Just as humans tend to compare our species to other primates in positive terms, such as with tool use and intelligence, our primate relatives can share hard-to-explain social dynamics that might harm other species as well. “I think that’s a really interesting, important thing for understanding ourselves, even if it also has this kind of grim side to it,” Crofoot says. Get the latest stories in your inbox every weekday.