Latest news with #capucinus
Yahoo
19-05-2025
- Science
- Yahoo
Monkeys are kidnapping babies of another species on a Panamanian island, perplexing scientists
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. At first, behavioral ecologist Zoë Goldsborough thought the small figure seen on the back of a capuchin monkey in her camera trap footage was just a baby capuchin. But something, she said, seemed off. A closer look revealed the figure's unexpected coloration. She quickly sent a screenshot to her research collaborators. They were perplexed. 'I realized that it was really something that we hadn't seen before,' Goldsborough said. Further observation of the video and cross-checking among researchers revealed that the small figure was actually a monkey of a different species — a baby howler. 'I was shocked,' Goldsborough said. As Goldsborough searched through the rest of her footage, she noticed the same adult monkey — a white-faced capuchin nicknamed 'Joker' for the scar on his mouth — carrying a baby howler monkey in other clips, too. Then, she noticed other male capuchins, known scientifically as Cebus capucinus imitator, doing the same thing. But why? Using 15 months of camera-trap footage from their research site on Jicarón Island, a small island 55 kilometers (34 miles) off the coast of Panama and part of Coiba National Park, Goldsborough's collaborators from the Max Planck Institute of Animal Behavior, University of Konstanz, and Smithsonian Tropical Research Institute, among others, studied the odd behavior to find an answer. They found that, starting with Joker, four subadult and juvenile male capuchin monkeys had abducted at least 11 infant howler monkeys between January 2022 and March 2023. With no evidence of the capuchins eating, caring for or playing with the infants, the study authors suspect the kidnapping behavior is a kind of 'cultural fad' — and potentially a symptom of the monkeys' unique conditions in the ecosystem of Jicarón. They reported their initial findings Monday in the journal Current Biology. Still, many questions remain. And unraveling the mystery could be crucial, the researchers said. The howler population on Jicarón is an endangered subspecies of mantled howler monkeys, Alouatta palliata coibensis, according to the IUCN Red List of Threatened Species, a global assessment of species' vulnerability to extinction. Additionally, howler monkey moms give birth only once every two years, on average. Examining the capuchin kidnapper case 'was kind of like a roller coaster where we kept having different interpretations, and then we would find something that proved that wrong,' said Goldsborough, the study's lead author and a doctoral student with the Max Planck Institute of Animal Behavior and University of Konstanz. Jicarón Island is uninhabited by humans. With no electricity and a rocky terrain, scientists have to haul their gear and other materials to the island with boats when the tides are right, making in-person observations of the skittish capuchin monkeys difficult. That's why they use camera traps: hidden, motion-triggered cameras that capture photos and videos of the ground-dwelling capuchins. But there's a major limitation to their work: You don't know what you can't see, and the camera traps don't capture what's happening in the treetops, where howler monkeys live. So, the study team couldn't definitively confirm how, when, or why capuchins abducted the babies. At first, the researchers thought it was a rare, one-time case of adoption. Monkeys have been known to 'adopt' abandoned infants of the same or other species. But Joker wasn't caring for the howlers — he was just carrying them on his back, with no clear benefit to himself, until the infants eventually perished of starvation without access to breast milk. It's an odd behavior for male primates, said Pedro Dias, a primatologist at Veracruzana University in Mexico who studies Mexico's mantled howler monkeys and was not involved in the research. In primatology, it's fairly common to find females adopting or abducting infants to then care for them as a maternal instinct, he said. But on Jicarón, the males were not providing maternal care. When behavioral ecologist Corinna Most first read about the Jicarón monkey kidnappings, she suspected something else was going on. 'They're probably eating these babies,' said Most, an adjunct associate professor at Iowa State University who studies baboons, of her initial thoughts. Abduction for predation isn't uncommon in the animal world, added Most, who was not involved with the research. But as she learned more about the team's observations, she was surprised to find that wasn't happening in this case, either. Instead, the capuchins toted around the baby howlers for days with few interactions — no play, minimal aggression and little interest. Why they would exert the energy to steal babies is largely unclear, said study coauthor Brendan Barrett, a behavioral ecologist and Goldsborough's adviser. However, it's important to note that these island capuchins evolved in a different environment from their mainland relatives, explained Barrett. Capuchins are 'destructive, explorative agents of chaos,' he said. Even on the mainland, they rip things apart, hit wasp nests, wrestle with each other, harass other species and poke around just to see what happens. On an island without predators, 'that makes it less risky to do stupid things,' Barrett said. Island capuchins can also spread out since they don't need strength in numbers for protection, allowing them to explore. With this relative safety and freedom, Jicarón's capuchin monkeys might be a bit bored, the researchers proposed. Boredom, it turns out, could be a key driver of innovation — particularly on islands, and particularly among younger individuals of a species. This idea is the focus of Goldsborough's thesis research on Jicarón and Coiba's capuchins, the only monkey populations in these areas that have been observed using stones as tools to crack nuts. Consistent with the abductions, it's only the males who use tools on Jicarón, which remains a mystery to the researchers. 'We know that cultural innovation, in several cases, is linked to the youngest and not the oldest,' Dias said. For example, evidence of potato-washing behavior in macaques on Japan's Koshima Island was first observed in a young female nicknamed Imo. There are a few possible reasons for this, Dias explained. Adolescence is a time during which primates are independent from their mothers, when they start to forage and explore on their own. At that stage the monkeys also aren't fully integrated into their group's society yet. Over-imitation — a tendency in human children to imitate the behavior of others even if they don't understand it — could possibly be at play as well, Most said. This over-imitation isn't found in other animals, Most emphasized, but, 'I almost feel like this is what these other capuchins are doing,' perhaps as a way to socially bond with Joker, she observed. Most said she has usually thought that necessity, rather than free time, is the mother of invention in nature. But 'this paper makes a good case for (the idea that) maybe sometimes animals that are really smart, like capuchins, just get bored,' she noted. People and other primates famously share a certain level of intelligence defined by tool usage and other metrics, but some shared traits could be less desirable, Goldsborough said. 'One of the ways we are different from many animals is that we have many of these sort of arbitrary, nearly functionless cultural traditions that really harm other animals,' she added. As a kid growing up in the northeastern United States, Barrett said he used to catch frogs and lightning bugs in mason jars while exploring the outdoors. While he never meant to hurt them, he knows those activities usually aren't pleasant for the animal. It's possible that the capuchins' kidnapping behavior is similarly arbitrary — if not moderately entertaining for them. Barrett and Goldsborough said they hope this new behavior fades away, much like fads among humans come and go. Or perhaps the howler monkeys will catch onto what's happening and adapt their behavior to better protect their babies, Goldsborough added. 'It kind of is like a mirror that reflects upon ourselves,' Barrett said, 'of us seemingly doing things to other species that can harm them and seem atrocious that have no real purpose.'
Yahoo
19-05-2025
- Science
- Yahoo
Bored Capuchin Monkeys Are Kidnapping Howler Babies in Weird New 'Trend'
Off the coast of Panama, on an island uninhabited by humans, a culture unlike any other has arisen. On Jicarón Island, white-faced capuchin monkeys (Cebus capucinus imitator) rule, unmolested by predators. In their peace, and safety, they exhibit fascinating behaviors, wielding stone tools to facilitate their foraging in a way that may have once been thought unique to humans. Now, the monkeys have taken their shenanigans a step further. They have been caught doing something that scientists had never seen before: kidnapping the babies of howler monkeys (Alouatta palliata coibensis) and carrying them around like some sort of bizarre accessory. After poring and puzzling over the observations, a team led by behavioral ecologist Zoë Goldsborough of the Max Planck Institute of Animal Behavior concluded nothing explained the behavior as aptly as a fashion, or fad. "Scientists continue to uncover evidence of culture across animal taxa, and a behavior is considered cultural if it spreads between individuals via social learning," Goldsborough told ScienceAlert. "The howler-carrying behavior we describe is indeed part of this capuchin group's culture." Fads are not commonly identified in non-human animals. Examples include the peculiar intermittent salmon hats sported by orcas, and chimpanzees in Zambia wearing grass in their ears. These 'fads' are behaviors that the animals learn from each other, and serve no discernible purpose, like … planking, for example. Goldsborough and her colleagues had set up camera traps around Jicarón to monitor the capuchins' fascinating tool use. The scientists first got wind that something strange was going on with the monkeys when one individual, named Joker, was spotted going about his business with a baby howler monkey clinging to his fur. "It was so weird that I went straight to my advisor's office to ask him what it was," Goldsborough says in a statement. Alerted that shenanigans were indeed afoot, the researchers started paying closer attention. Goldsborough studied data collected by the camera traps, and found evidence of Joker carrying, at different times, four different baby howler monkeys. Then, it got weirder. Several months later, the behavior re-emerged. At first, the team thought Joker was resuming his strange hobby – but then they realized different capuchins were getting involved. In total, their observations over a 15-month period found five capuchins (including Joker) carrying 11 different howler monkey babies. At first, the puzzled scientists thought that the capuchins might be adopting the babies. But interspecies adoption is rare, and usually conducted by females. All five of the howler-carrying capuchins were males. In addition, the capuchins didn't seem interested in caring for the babies – all are assumed to have eventually died of starvation, with four confirmed dead. "The capuchin carriers do not seem to interact with the howler infants a lot besides carrying them. So they do not play with them, or try to groom them," Goldsborough explained to ScienceAlert. "To me, it appears less as if they want to keep the howler infant because they are so interested in them and interacting with them, but more that they carry them as an 'accessory' and are interested in the carrying behavior." But that's only part of the equation. There's the question of why are the capuchins carrying howler babies; the other question is, why these capuchins, and only these capuchins? "This is a fascinating question, since howler monkeys and capuchin monkeys co-occur in most of their ranges, and often interact, but never like this," Goldsborough said. Interestingly, the answer appears to be simple boredom. The capuchin population on Jicarón has no predators, and few competitors. They live a pretty cushy, relaxed life and may be somewhat understimulated, the researchers hypothesize – a lifestyle that has been linked to innovation in humans and other animals. "We think the conditions on Jicarón Island, specifically the lack of terrestrial predators and potentially greater amount of free time, are very conducive to the innovation and spread of behaviors," Goldsborough explained. The researchers plan to continue investigating this behavior to see if it evolves, or other fads emerge. Goldsborough also noted that she'd like to learn more about how the howler monkeys are responding to it. Until a handful of shit-stirring capuchins decided their babies might make dapper accoutrements, they were also living in a predator-free environment. Now, their babies lives' are being threatened. There may also be some fascinating philosophical insights to be gleaned. "One of the reasons our discovery elicits such interest is because it provides a mirror into ourselves. Humans often try to compare ourselves to other animals to find similarities and differences, and this is usually focused on positive qualities (e.g., language, tool use, empathy)," Goldsborough said. "However, if you think about it, humans have many seemingly arbitrary cultural traditions that harm other species. Finding that this type of culture is not limited to humans, but might also occur in other intelligent animals living in the right conditions, is a fascinating implication of our findings." The research has been published in Current Biology. You can also explore the documented rise and spread of the behavior on an interactive website here. Terrifying Video Shows Earth Cracking And Sliding During Myanmar Quake Scientists Recreated The Ancient Chemical Reactions That May Have Sparked Life Mystery of T. Rex's Debated North American Origins Finally Solved
National Geographic
19-05-2025
- Entertainment
- National Geographic
These capuchins are abducting babies from howler monkeys—for fun?
A young male nicknamed Joker was probably the first to start carrying a howler monkey baby on his back for days on end. Then a group of other young males started to copy him. Here a white-faced capuchin monkey perches on a tree branch in Manuel Antonio National Park in Costa Rica. A group from the same genus has been observed with stolen howler monkey babies on a small island off the coast of Panama. Photograph By Eric Kruszewski, Nat Geo Image Collection On a tiny island off the coast of Panama called Jicarón, a male capuchin monkey called Joker appears to have started a disturbing trend. Camera traps caught Joker, nicknamed for the scar on his face, and other male white-faced capuchins (Cebus capucinus imitator) carrying kidnapped howler monkey infants on their backs. Researchers originally set up the traps in 2017 after a botanist visiting the island had reported the monkeys using stones to process food, which had never been seen before in the more slender kind of capuchin that inhabits Costa Rica and Panama. The cameras did reveal one group of capuchins using stone tools and anvils to crack open seeds, fruits, even crabs and snails. Yet as the team reports in the journal Current Biology this week, the footage also captured this bizarre baby-snatching fad, something never seen before. 'It was so weird that I went straight to my advisor's office to ask him what it was,' says primatologist Zoë Goldsborough of the Max Planck Institute of Animal Behavior and the Smithsonian Tropical Research Institute. (Capuchins are known for their ingenuity—another species is 3,000 years into its own 'Stone Age'.) A bizarre new trend A recording dated January 26, 2022, first documented an unidentified young capuchin male carrying a howler monkey (Alouatta palliata coibensis) infant. The next day Joker was carrying that same infant. And so he did for days on end, at least until February 3. 'Our first thought was that maybe this infant had been abandoned by the howlers, and then adopted,' Goldsborough says. There was one known case of a marmoset monkey infant being adopted by a different species of capuchin in Brazil. But crucially, that baby was adopted by a female who could nurse it, says Patrícia Izar of the University of São Paulo, who reported that finding in 2006. Capuchin males, on the other hand, don't have a clue what to do. And so the kidnapped howler infant very likely died of starvation. What's more, the poor infant was making the kind of calls it usually makes when separated from its mom—and later on, some adult howlers called out as well, indicating the infant had not been abandoned, but abducted instead. 'We don't have footage of how the capuchins did this,' says study coauthor Brendan Barrett, a behavioral ecologist at Max Planck. 'But we know they are not afraid to gang up on much larger howlers.' Things were about to get a whole lot weirder. In April and May, Joker was seen carrying another howler infant, and then another. Footage also showed him dragging a third one, possibly dead, with some other young males tagging along. Then, between September and March, the situation escalated: Four other males were seen carrying live howler infants on their backs or bellies, sometimes for more than a week. Over a span of 15 months, at least 11 infants had been abducted—and few if any are likely to have survived. While there had been at least one earlier report of a capuchin from a larger species in Brazil stealing a howler monkey infant and carrying it off in its mouth, presumably to eat it, this study is the first to document white-faced capuchins abducting infants in this way—and researchers are especially fascinated that the behavior was subsequently picked up by other individuals, too. 'This observation is particularly intriguing because examples of the social spread of such behaviors with no apparent fitness benefits in animals other than humans are rare,' says Izar. Because there had been camera traps on the island for years before this behavior was ever observed, the researchers probably captured the first time it happened, or at least a very early occurrence. It is not unusual for young capuchin males to be seen carrying infants of their own species, says Susan Perry of the University of California, Los Angeles, who has studied Costa Rican capuchins at another site for decades, but was not involved in the current study. 'Capuchin males often try to steal capuchin infants, and they seem extremely pleased—as if they've won a prize—when they succeed. Until the infant gets hungry and starts crying for milk.' At that point, the infants tend to be abandoned. 'Fortunately, the infant's mother or other female relatives are usually lurking nearby to retrieve their infants.' Capuchin males have a preference for male infants, says Perry. 'We think the infants they develop a close relationship with early on will often grow up to become allies with whom they can make the risky move to another group to mate.' Abducting howler monkeys would obviously be useless in this regard, but perhaps their urge to carry infants is so strong that it sometimes misfires, says Perry. Goldsborough and Barrett agree, but they believe another tendency may be misfiring as well—the desire to do as others do. Perhaps Joker really just wanted to carry an infant, and then the others just wanted to have a go at it as well. Not that it improved their social standing—young males carrying howler infants appeared to be the target of aggression from other capuchins more often than those that weren't. But for a species in which learning a new technique to get your hands on difficult-to-reach but nutritious foods is an important part of growing up, perhaps the tendency to do as others do pays off often enough to be indiscriminate. Island life may bore capuchins The island environment could be a factor, too, the researchers argue. On the mainland, capuchins usually have to be wary of predators, and foraging takes up more time when you have to be constantly on guard and stay close to the group. On an island with plenty of food and hardly any threats, perhaps young males are just bored. 'Animals living on islands with no predators—or in zoos, were they are also safe and well-fed—have often been found to be more innovative and better at using tools,' says Goldsborough. In many cases, what bored animals come up with may be useless or even annoying, says Barrett. 'I've seen capuchins groom porcupines and smack cows on the butt. They mess with everything. They're just constantly testing and interacting with the world.' But occasionally, an individual will find that, hey, if you swing a rock at one of these smelly, colorful things on the beach, there's a tasty treat inside. Or that if you hang out with male infants, they'll have your back when they grow up. Some capuchins also develop strange rituals with no other purpose than strengthening social bonds. It's all in a day's work for this large-brained, hypersocial, tirelessly inventive species that in many ways resembles our own, even though our last common ancestor lived around 38 million years ago. But what about the poor howlers, an endangered species on Jicarón, whose babies are being abducted? 'It's tragic,' says Goldsborough, 'but as researchers, we don't intend to interfere with natural behavior. I hope the howlers will eventually adapt, for example by keeping a safe distance from this one population of capuchins, or that the capuchins themselves will eventually tire of this. Those howler infants can be quite a handful.'
