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    Fire-prone neighborhoods on the fringes of nature are rapidly expanding

    People are flocking to nature’s doorstep, and into wildfire territory.

    Homes constructed where human development meets undeveloped wildland are particularly vulnerable to wildfires and other natural hazards (SN: 11/9/23). Nonetheless, people are moving into the wildland-urban interface, or WUI, and rapidly expanding it. From 2000 to 2020, the global footprint of the WUI grew by about 35 percent, reaching a total area that’s roughly the size of Mexico, researchers report November 8 in Science Advances. More

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    Meet Chonkus, the mutant cyanobacteria that could help sink climate change

    Stand back, ordinary ocean-dwelling, oxygen-spewing organisms: There’s a new green, hulkish mutant in town.

    And hefty UTEX 3222 — dubbed “Chonkus” by the researchers who found it — may have just the right combination of traits to help with some of humanity’s most pressing problems. In particular, Chonkus could help fight climate change, report microbiologist Max Schubert, formerly of the Wyss Institute at Harvard and now launching a start-up, and colleagues in a study published October 29 in Applied and Environmental Microbiology.  

    Chonkus (right) settles quickly to the bottom of a water-filled test tube, compared with another strain of cyanobacteria (left). That quick accumulation of green sludge could make it more useful for sequestering atmospheric carbon dioxide.Ted Chavkin

    Chonkus was discovered in the shallow sunlit waters off the coast of Italy’s Vulcano Island, where volcanic gas-rich groundwater seeps into the sea. It’s an environment that Schubert and colleagues suspected to be fertile ground for finding photosynthesizing, carbon-consuming microbes. The waters collected from those seeps turned out to contain a spontaneous mutant strain of Synechococcus elongatus, a species of photosynthesizing bacteria that’s at the base of ocean food webs around the world (SN: 10/20/16; SN: 6/9/16).

    S. elongatus is a favorite lab organism, because of how quickly it grows and how resistant it is to environmental stressors (SN: 6/14/17). And Chonkus, the new mutant, is like a superpowered version, the team found. When they cultured the strain in the laboratory, its individual cells were larger than those of other fast-growing cyanobacteria, and it built larger colonies. The mutant also contained more carbon than other strains of S. elongatus, apparently stored in white granules within its cells. The strain was also heavy: When placed into a test tube, the cyanobacteria rapidly sank to the bottom, forming a dense sludge. More

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    This marine biologist discovered a unique blue whale population in Sri Lanka

    Pooping whales changed the course of Asha de Vos’ career.

    The Sri Lankan marine biologist was aboard a research vessel near her home island in 2003 when she spotted six blue whales congregating. A bright red plume of whale waste was spreading across the water’s surface.

    Seeing whale poop, colored red thanks to the whale’s diet, was the first clue that Sri Lanka’s blue whales don’t migrate between feeding and breeding areas.A. de Vos

    De Vos, then a master’s student, recalls being “super excited.” What she witnessed went against prevailing dogma: Her textbooks and professors had taught that blue whales, like other large whales, embark on long-distance migrations between colder feeding areas and warmer breeding and calving areas. But seeing whales pooping in tropical waters meant the behemoths must be feasting locally.

    Intrigued, de Vos spent the next few years documenting how blue whales near Sri Lanka differ from those elsewhere in the world. For one, the population feeds on shrimp rather than krill. The whales also have unique songs. But the key difference, she realized, is that they remain year-round in the waters between Sri Lanka, Oman and the Maldives — making them the only nonmigratory blue whales in the world. Abundant upwellings of nutrient-rich water from the ocean depths support a steady food supply for the whales.

    Eventually, the International Whaling Commission, the intergovernmental body dedicated to protecting whales, recognized Sri Lanka’s blue whales as a distinct subspecies called Balaenoptera musculus indica.

    By studying the blue whales around Sri Lanka, marine biologist Asha de Vos discovered they are the only nonmigratory blue whales in the world.Franco Banfi/Nature Picture Library/Alamy Stock Photo

    This distinction is crucial for conservation management, explains retired whale biologist Phillip Clapham, formerly of the U.S. National Oceanic and Atmospheric Administration’s National Marine Fisheries Service. Small, localized populations — like the one in Sri Lanka — face higher risks of being wiped out in the face of environmental or human threats, such as deep-sea mining.

    More than two decades on, de Vos is now one of Sri Lanka’s most renowned scientists — famed for nurturing the country’s nascent marine biology scene. She is also an ardent champion for greater diversity among researchers in ocean conservation. More

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    Fans may not keep older adults cool during heat waves

    Air blowing from an electric fan alone isn’t enough to cool off older adults sweltering indoors in a heat wave, new research shows. A study of 18 adults aged 65 to 72, monitored in a controlled-climate chamber simulating extreme heat wave conditions, found little difference in peak core temperatures as a result of electric fan use, scientists report October 17 in the Journal of the American Medical Association.

    Older adults, many of whom prefer to weather heat waves their own homes, are particularly at risk for heat-related health impacts (SN: 5/14/24). In the absence of access to air conditioning, using pedestal-style electric fans has been one recommended strategy for individuals at home to try to stay cool. Fans can speed up heat loss, lowering the body’s core temperature, by increasing sweat evaporation. More

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    An idea to save Mexico’s oyamel forests could help monarch butterflies too

    An experiment to grow new forests in central Mexico offers hope that the crucial winter habitat for millions of migrating monarch butterflies could survive into the next century.

    When scientists decided to plant hundreds of baby oyamel fir trees (Abies religiosa) about 100 kilometers from their native habitat, they weren’t sure how many trees would survive. Today, most of the saplings are flourishing, researchers report September 17 in Frontiers in Forests and Global Change. Even at an altitude of 3,800 meters, high above where the trees usually grow, almost 70 percent of the saplings survived at least three years. More

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    How tiny phytoplankton trek long distances upward in the ocean

    It’s one of the most massive migrations on Earth: a huge biomass of tiny plankton that travel from deep in the sea toward the surface. Yet not all of those organisms have limbs to propel themselves upward. So how some of them manage to undergo such a long journey has been a mystery.

    Now, a team of researchers has shown that one species of phytoplankton has an ingenious solution: swelling to six times its original size. The process reduces its density and allows it to float upward like a helium balloon, bioengineer Manu Prakash and his colleagues at Stanford University report October 17 in Current Biology. More

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    What leads rivers to suddenly change course?

    Shifting is in a river’s nature. But when a river breaks free of its channel and carves a new path across the landscape, devastating floods may descend upon communities with little to no warning.

    For decades, researchers have struggled to explain exactly how river channels become primed for such sudden diversions, or avulsions. A study published September 18 in Nature may have finally quelled the debate, showing how two factors work together to stage the rerouting of a river. Building on their findings, the researchers also developed a promising algorithm that can predict the new path of a river that has avulsed. More

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    Climate change fueled the fury of hurricanes Helene and Milton

    Meteorologists have watched in awe as Hurricane Milton, churning over the anomalously warm waters in the Gulf of Mexico, swiftly transformed into one of the strongest Atlantic storms on record.

    Over just 20 hours on October 7, Hurricane Milton explosively intensified from a Category 1 to a catastrophic Category 5 storm, with sustained winds of 290 kilometers per hour (180 miles per hour). The storm is expected to make landfall on the west coast of Florida either late on October 9 or early October 10 as a major Category 3 or 4 hurricane, bringing deadly storm surge and hurricane-force winds to coastal regions still reeling from Hurricane Helene just two weeks earlier (SN: 10/1/24). More