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Scientific American
15-05-2025
- Science
- Scientific American
Friend or Food: Why Are Iceland's Orcas Taking in Pilot Whales?
One day in June 2022 Chérine Baumgartner, a researcher at the Icelandic Orca Project, was watching from a dinghy as a pod of killer whales fed on herring—when she noticed something very odd about what seemed to be a young member of the pod. 'At first, we were like, 'Oh my god, this killer whale calf has a problem,'' she says. It was far tinier than normal and lacked an infant orca's characteristic black-and-pale-orange coloration. Baumgartner, now a Ph.D. student at the Swiss Federal Institute of Technology Zurich, suddenly realized she was seeing an entirely different species: a baby pilot whale. She and her team observed the pod for nearly three hours before weather conditions forced them back to land. They found the pod the next day, but the pilot whale calf was nowhere to be seen. Scientists noticed orcas interacting with baby pilot whales off Iceland every year from 2021 to 2023. Each instance was short-lived and featured different individual pilot whales (dark-gray members of the dolphin family with a bulbous forehead) and different pods of orcas. Now, in a new study in Ecology and Evolution, Baumgartner and her colleagues describe the 2022 and 2023 incidents and posit three potential explanations: predation, play or parenting. On supporting science journalism If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. In all the sightings, a weeks-old pilot whale swam by a female killer whale in what scientists call an echelon position, with the young whale located beside and slightly behind the adult orca. In the 2022 and 2023 instances, the killer whales occasionally nudged the calf along. In 2023 a calf was seen swimming ahead of the group, possibly as if to run away—and at one point it was lifted, belly-up, out of the water on the back of an orca. With the first possible explanation, the killer whales could have been keeping the young pilot whales around like a living lunch box; some orcas in Iceland are known to eat harbor seals and porpoises. But Baumgartner notes that these Icelandic killer whales are predominantly fish eaters and that they didn't display overtly aggressive behavior toward the pilot whale calves. So predation is less likely, though not impossible, she and her colleagues say. Alternatively, the killer whales could have been playing with the young whales or using them to practice hunting. Iceland's orcas often herd herring, and they could have been incorporating the pilot whale calves in their hunting games. Finally, the killer whales could have been extending their parental instincts to the young calves. Whales and dolphins in the wild often care for the young of other members of their pod, and although it's rare, dolphins have adopted calves from different species. In the pilot whales' case, Baumgartner says, she wouldn't categorize the relationship as adoption because the interactions seemed to be short-lived. The young pilot whales would likely have died without milk, and none of the female orcas were lactating at the time. These three possibilities also aren't mutually exclusive, she says. 'It could be [that the orcas] encountered the pilot whale opportunistically, and some individuals played with the whale, and others tried to nurture it,' Baumgartner adds. The other conspicuously missing pieces of the puzzle are how, in each instance, the orcas came across a pilot whale calf in the first place and what happened to that calf afterward. 'Was it lost or abandoned?' asks study co-author Filipa Samarra, principal investigator at the Icelandic Orca Project and director of the University of Iceland's research center on the Westman Islands. 'Or did the killer whales actively approach to take the calf away?' The researchers also wonder if the calves escaped or died or were killed or eaten by the orcas. Sarah Teman, a graduate student in ecology at the University of Washington, who was not involved with the new study, says her jaw dropped when she saw pictures of the pilot whales with the orca pods. Teman previously studied southern resident killer whales interacting with porpoises in the Salish Sea off British Columbia and Washington State. In that research, she observed interactions that may have been motivated by nurturing, hunting practice or 'play'—and often ended up killing the porpoises. 'It was fascinating to see such similar behaviors' in the Icelandic orcas, she says, adding that the animals' interactions with the pilot whales seemed to be largely driven by nurturing or play behavior, just as had been seen in the southern resident killer whales' interactions with porpoises. Samarra also speculates that the unusual interactions off Iceland could be a result of climate change because pilot whales increasingly follow schools of mackerel moving into warmer waters that overlap with the killer whales' range. She hopes that, next summer, her group will finally observe how the young pilot whales get entangled with the orcas and what happens to them next.
Express Tribune
14-05-2025
- Health
- Express Tribune
Chimpanzees medicinal leaves: Scientists find species use medicinal leaves to treat wounds, help others
Listen to article Chimpanzees in Uganda's Budongo Forest have been observed treating their own wounds — and those of others — using medicinal plants, in a discovery that researchers say offers crucial insights into the evolutionary roots of human healthcare. The study, published in Frontiers in Ecology and Evolution, details 41 cases of wound care among two chimpanzee communities, Sonso and Waibira, including seven instances of prosocial care — where chimpanzees treated unrelated individuals. These behaviours included licking wounds, applying chewed leaves, and dabbing plant matter, often using species with proven antimicrobial or healing properties. 'This is one of the first studies to systematically document self-medication and caregiving in wild chimpanzees using medicinal plants,' said lead researcher Dr Elodie Freymann of the University of Oxford. 'It expands our understanding of the cognitive and social foundations of human health behaviours.' Chimpanzees were seen cleaning genitals and wiping themselves with leaves — hygiene behaviours potentially preventing infection. Injuries in the chimpanzees, often from snares or group conflicts, were treated without human intervention, and all observed individuals recovered. Remarkably, four of the seven prosocial cases involved care for non-relatives, suggesting possible altruistic tendencies or social strategies to form alliances. The findings have implications for conservation. As habitats shrink and snares threaten populations, preserving access to medicinal plants and understanding natural behaviours like self-care could inform protective strategies for endangered primates. Researchers call the Budongo site an invaluable location for studying zoopharmacognosy — the scientific term for animal self-medication — and plan further work in South America.
Yahoo
14-02-2025
- Science
- Yahoo
Newly discovered fungus turns cave-dwelling spiders into ‘zombies'
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Scientists in Europe have identified a previously unknown species of fungus that turns cave spiders into 'zombies.' The fungus lures them out of their webs before instigating an untimely death and then uses the spiders' corpses to spread its spores. The newly discovered species, named Gibellula attenboroughii, acts in a similar way as the zombie ant fungus, seemingly manipulating its prey to move to a more suitable spot for the fungus to spread, according to a study published January 24 in the journal Fungal Systematics and Evolution. But the way in which the fungus affects the arachnid's brain is still a mystery, and a multitude of questions remain about the fungus' evolutionary pathway and ecological impacts. 'We know very well the ants, the wasps, and very few other examples. And now this is in a different family, so it's a new origin of behavior manipulation,' said study coauthor Dr. João Araújo, a mycologist at the Natural History Museum of Denmark and an assistant professor at the University of Copenhagen. 'It's something really interesting that's not super common in the parasitic world.' The finding opens up new research opportunities to better understand animal-controlling fungus and illuminates the diversity of fungi yet to be uncovered, researchers said. The newfound species is part of a larger branch of fungi that exclusively infects spiders. Researchers observed a different species of Gibellula (G. aurea found in Brazil) possibly manipulating spiders to move to the underside of leaves before death, as described in a November 2022 study coauthored by Araújo. However, the maneuver was not as strikingly evident as it is when G. attenboroughii targets cave spiders, Araújo said. So far, scientists have only observed G. attenboroughii infecting the spiders Metellina merianae and Meta menardi, both cave-dwelling orb weavers that are found in Europe. The first sighting of the peculiar fungus has a colorful backstory: In 2021, a television crew first spotted the fungus on an orb weaver spider while filming a show in an abandoned gunpowder storeroom at Castle Espie Wetland Centre in Northern Ireland's County Down. The crew noticed that the spider placed itself in an exposed position before death, away from its web, suggesting the fungus had caused behavioral change. Further observations revealed more infected spiders in caves in both Northern Ireland and Ireland, all positioned in exposed areas of the roof or walls of the chambers, according to the study. 'Most spiders that are web-building spiders very much like to stay on their web. They're built to be good inside of a web, but then they're actually quite bad at walking around on the ground,' said Dr. Jay Stafstrom, an expert on arachnid sensory ecology and postdoctoral researcher at Cornell University in Ithaca, New York. 'The fact that a fungus can infect something and then behaviorally alter that animal so that it then helps the fungus spread, I think it's just very intriguing,' said Stafstrom, who was not part of the study. The researchers said they are unsure of the exact mechanics and inner workings of the fungus. But the team hypothesizes the fungus lures the spiders out of their lairs where they are exposed to circulating air currents, which helps spread its spores, said Araújo, who is also an honorary research associate at the Royal Botanic Gardens, Kew, in the United Kingdom. The authors have not yet identified which metabolites — compounds produced by the fungus that can interact with other organisms — G. attenboroughii is releasing in the brain of the host. More research is required to know the fungus' ecological impact, but Araújo said he does not believe there is any cause for concern about the affected spider species. 'Fungi have evolved many millions of years ago, more than 100 million years ago, and they have been coexisting with these spiders and other species of fungi and other insects,' Araújo said. 'Actually, we can hypothesize that they keep the forest in balance,' he added, pointing to the case of the zombie ant fungi. Scientists have documented the lethal parasite regulating the insect population, Araújo said. Around 150,000 species of fungi have been formally documented, but it's estimated that number is only around 5% of the diversity of fungus out there to be discovered, said Dr. Matthew Nelsen, an evolutionary biologist and research scientist at Chicago's Field Museum of Natural History, who was not part of the new study. 'This study draws attention to this challenge and will further inspire the community to work to close this gap,' Nelsen added in an email. The authors also noted the presence of mycoparasites observed eating the zombie spider fungus, 'demonstrating that these spiders are important food sources for fungi, which in turn support other fungi. Together, this serves to shine a light on the complex and diverse world around us,' Nelsen said. The premise of zombie fungus can quickly turn into a horror story when reimagined as a sci-fi creature infecting humans, such as in the HBO series 'The Last of Us,' said to have been inspired by the zombie ant fungus. (HBO shares parent company Warner Bros. Discovery with CNN.) Since this newly discovered fungus only affects spiders, humans need not worry about Gibellula attenboroughii, Nelsen said. 'While there are absolutely some cave-dwelling fungi that are problematic for humans, this is part of a group of fungi that only infects spiders. Jumping to humans would require it to evolve tolerance to our warm body temperature and to circumvent our immune system, both of which serve as strong defenses against most fungi,' he added. Araújo said he and his team plan to continue studying the group of fungi that infects spiders to understand how these species are related, their origins, how they evolved, and more. Further understanding of these fungi could eventually lead to potential application in crop protection or even human medicine. 'Imagine, (with) a fungus that can control the behavior of a spider, which metabolites they're releasing in the brain of this spider,' Araújo said. 'This could be something really revolutionary for Alzheimer's and degenerative diseases and the ones that affect the brain. So maybe there's hope there.'
