ReportWire

Tag: Biology

  • Genetic analysis reveals new details on ancient human and Neanderthal couplings

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    NEW YORK — NEW YORK (AP) — Humans and Neanderthals cozied up from time to time when they lived in the same areas tens of thousands of years ago. But we don’t know much about who got with whom, or why.

    A new genetic analysis offers some ancient gossip: The pairings were more often female humans with male Neanderthals.

    How exactly this happened remains a huge question mark. Did human women venture into Neanderthal populations, or were the Neanderthal males drawn to larger human enclaves? Were these interactions peaceful, confusing, secretive or even violent?

    “I don’t know if we’ll ever get a definitive answer to how this happened, since we can’t travel back in time,” said population genetics expert Xinjun Zhang with the University of Michigan, commenting on the new analysis.

    But the study, published Thursday in the journal Science, shows “that whenever Neanderthals and modern humans have mated, there has been a preference for male Neanderthals and female modern humans, as opposed to the other way around,” said author Alexander Platt, who studies genetics at the University of Pennsylvania.

    Scientists know that Neanderthals and humans mated because there is a small but important percentage of Neanderthal DNA in most modern humans outside of sub-Saharan Africa — including genes that can help us fight some diseases and make us more susceptible to others.

    But they have also known that the Neanderthal DNA is not distributed evenly throughout the human genome.

    In particular, there is a surprising lack of Neanderthal DNA in the human X chromosome, one of the bundles of genes in each cell known as a sex chromosome, compared with the amount of Neanderthal DNA in the other, non-sex chromosomes in the cell.

    Scientists thought that maybe the genes in those locations were simply not beneficial – or even harmful. Perhaps people with those gene patterns didn’t survive as well so those genes were filtered out by evolution over time.

    Or, they thought, maybe the difference could be explained by how the two species intermingled.

    To try to solve the riddle, Platt and colleagues looked instead at the Neanderthal genome and the human DNA that got interspersed during a “mating event” 250,000 years ago.

    When comparing these genes, they found more of a human fingerprint on the Neanderthal X chromosome – the same chromosome that, in humans, has less Neanderthal DNA than would be expected.

    The most likely explanation for this mirror image pattern is mating behavior. That’s because of the way sex chromosomes are passed from parents to children, explained Platt. Because genetic females have two X chromosomes and genetic males have one X and one Y chromosomes, two out of every three X chromosomes in a population, on average, are inherited from people’s mothers.

    If more human females mated with Neanderthal males than the other way around, over thousands of years you would expect to see just what they found: more human DNA in Neanderthal X chromosomes and less Neanderthal DNA in human X chromosomes.

    “I think that they’ve taken some really important steps in filling missing pieces to the puzzle,” said Joshua Akey, who studies evolutionary genomics at Princeton University and wasn’t involved with the new study.

    The study can’t totally rule out other explanations. For example, Zhang said, it’s possible that the offspring of human males and Neanderthal females just didn’t survive as well.

    But the simplest and most likely, explanation, the study found, is also the most interesting: “It’s not the result of a strictly Darwinian survival of the fittest,” Platt said. “It’s really the result of how we interact with each other, and what our culture and society and behavior is like.”

    —-

    The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.

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  • As billionaires chase immortality, this startup cofounded by a Harvard genetics professor gets FDA approval for the first partial de-aging human trial | Fortune

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    A startup cofounded by a renowned Harvard geneticist has taken a step toward cracking the human body’s biological breakdown by securing FDA approval to test its cutting-edge gene therapy on humans.

    Life Biosciences, a biotech company cofounded by Harvard genetics professor David Sinclair, said Wednesday it had secured approval for a Phase 1 clinical trial aiming, in part, to restore vision in people with eye conditions such as glaucoma and non-arteritic anterior ischemic optic neuropathy (NAION) through “partial epigenetic reprogramming.” During the trial, researchers will attempt to turn back the biological clock on damaged cells in a person’s eye by directly injecting it. This allows the therapy to reach damaged retinal ganglion cells and deliver “rejuvenation instructions” directly to the target cells to help restore their function and potentially reverse vision loss.

    The company will enroll its first patients over the next couple of months, with results potentially coming by the end of the year or early next year, CEO Jerry McLaughlin told Fortune.

    McLaughlin, a pharmaceutical industry veteran who previously worked at Merck and at venture-backed biotechs such as Neos Therapeutics and AgeneBio said the approval was groundbreaking: “It’s a transformational day, I think, for science overall, for Life Biosciences, for the field of partial epigenetic reprogramming,” he said.

    The FDA approval, which McLaughlin said researchers in his industry have been waiting on for years, puts the lean Life Biosciences team (fewer than 20 people) ahead of the pack, as the longevity boom is increasingly being underwritten by billionaire money. 

    Altos Labs, one of the highest-profile bets on cell rejuvenation, launched with $3 billion in funding in 2022 and reportedly counts Amazon founder and the world’s fourth-wealthiest person Jeff Bezos as an early backer. Meanwhile, NewLimit, the longevity startup cofounded by billionaire Coinbase CEO Brian Armstrong last year raised $130 million in Series B financing, to pursue epigenetic reprogramming. Even Elon Musk, Tesla CEO and the richest man in the world, has recently entered the longevity chat, saying at Davos aging is a “very solvable problem.” 

    Tackling vision loss first

    Rather than focus on full-body de-aging, Life Biosciences’ is taking a “staged approach” to de-aging, first tackling optic neuropathies, conditions in which damage to the optic nerve erodes vision. The trial aims to restore some vision in both patients with glaucoma and NAION—both of which can cause blindness. Glaucoma is the second leading cause of blindness worldwide, according to Centers for Disease Control and Prevention, and it’s especially prevalent in adults between the ages of 64 and 84. NAION, meanwhile, is the “most common acute, optic neuropathy” in people over 50. McLaughlin said the company chose to focus on these diseases partly because of their outsized impact on patients.

    “The bad news is there’s absolutely nothing to treat [NAION], and the even worse news is that there’s about a 20-to-30% chance in the next two to three years it’s going to happen in the second eye,” he said.

    McLaughlin said Life Biosciences is already applying its epigenetic reprogramming to help treat other conditions. The company previously saw success in treating liver fibrosis, or MASH, which he said showed the company’s approach “transcends organs.” 

    While the company is first focused on helping patients with vision loss, McLaughlin isn’t ignorant about the potentially giant opportunity opening up thanks to a rapidly aging global population.

    “Our population replacement is not there in the U.S. We’re well below population replacement,” said McLaughlin. “It’s worse in other parts of the world, and with a rapidly aging population, extending healthy human lifespan is critical, from an economic standpoint, and for society overall.”

    The world’s cumulative fertility rate has been dropping for years, but the U.S. fertility rate, in particular, hit a record low in 2024, at 1.6 children per woman, below the replacement level of 2.1 children per woman. The country’s fertility rate is on par with other advanced economies, such as Iceland and the United Kingdom, according to data from the World Bank. Others come in even lower, like Japan, which recorded a fertility rate of 1.15 births per woman in 2024, according to a local government agency.

    The science behind Life Biosciences

    Life Biosciences cofounder and Harvard geneticist Sinclair is the key behind the company’s FDA breakthrough. Previously Sinclair, who earned a Ph.D. in molecular genetics from the University of New South Wales, led pioneering research on partial epigenetic reprogramming, partially de-aging cells by modifying their epigenome, biochemical markers that tell genes when to turn on or off without altering the underlying DNA sequence.  

    Sinclair’s research showed that, by using three of four proteins that Nobel-prize winning Japanese scientist Shinya Yamanaka previously found could fully reset the age of a stem cell to pluripotency—or a blank state—researchers could rejuvenate cells without resetting them so fully that they “forget” their original function. Partially resetting the cells had more potential for therapeutic uses because these cells “maintain” their identity, as they partially de-age, unlike the fully reset cells that “forget” their function and can turn into tumors.

    Sinclair laid the foundation for his work using mice in preclinical trials, Life Biosciences then licensed the technology from Harvard and Sinclair’s lab to test on non-human primates to better match the human eye’s anatomy.

    In those studies, McLaughlin said, Life Biosciences induced a NAION-like injury and then used the treatment to reverse the vision loss and restore it to that of a healthy primate.

    Despite the increasing competition in the space, McLaughlin isn’t scared of competitors, and he said the large amount of money and activity in the longevity space is warranted. Following the FDA approval, more companies may even follow Life Biosciences’ footsteps and focus more on epigenetic reprogramming, he said, which could overall be positive for the field.

    “We believe this has some of the highest prospects, best prospects, in aging science—partial epigenetic reprogramming,” he said. “As we continue to generate evidence, evidence is only going to bring more people to the field.”

    This story was originally featured on Fortune.com

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    Marco Quiroz-Gutierrez

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  • 34 Ocean Activities, Experiments, and Crafts for Kids To Dive Into

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    Have you ever watched as a child stares into an aquarium with awe? Whether it’s the song “Baby Beluga” or the movie Finding Nemo, kids love all things ocean! So you know they’ll be eager to dive into this collection of ocean activities and crafts. Whether it is a science experiment to learn how acid affects seashells, an art lesson where students create their own underwater scene, or a writing prompt about the ocean, students will learn all about our watery planet. Come on in … the water’s fine!

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    FREE PRINTABLE

    Science Experiment Recording Worksheet

    Our free printable recording worksheet is perfect for any science experiment or demo! Grab yours to use with the ocean experiments shown here.

    We Are Teachers

    Ocean Experiments and Learning Activities

    WWF's Wild Classroom slide show slide about sea turtles

    FEATURED PICK

    1. Learn about sea turtles and marine ecosystems

    Make a splash with Wild Classroom’s free Sea Turtles and Oceans Toolkit. This ready-to-use resource helps students learn about ocean ecosystems by providing an educator’s guide, presentation, and fun, cross-curricular activities. You will also get bonus resources like quizzes and a video playlist, offering diverse ways to enrich your lessons. It is a great way to build critical thinking skills and inspire a love for ocean conservation.

    2. Make an ocean in a bottle

    Turn an old water bottle into a mini-aquarium. Fill it about a third of the way with sand. Then drop in some small shells and plastic fish and other sea creatures. Finally, top the bottle off with water (it’s up to you whether you want to dye it light blue first) and screw on the lid. (Avoid spills by adding a few drops of glue to the threads of the cap first.) Now kids can explore the ocean anywhere they go!

    3. Take a virtual aquarium field trip

    Can’t get to the aquarium? No problem! Take a virtual field trip instead with live webcams and video tours. 

    Learn more: Best Aquarium Virtual Field Trips

    4. Learn how ocean currents work

    a science experiment that shows with blue and red water in a shallow dish how ocean currents work
    Adrienne Hathaway for We Are Teachers

    All you need for this science experiment is a shallow dish, hot and cold water, and some food coloring. Fill the dish about halfway with cold water that’s tinted light blue. Add some ice and stir so your water becomes very cold. Bring a few cups of water to a boil, adding food coloring to make it very bright red. Slowly (and carefully!) pour some hot water into one corner of the dish. Watch as the warm and cold water swirls and mixes, simulating the ocean currents that are formed the same way!

    5. Assemble ocean zone bottles

    Learn the zones of the ocean with this simple ocean activity. Round up four empty bottles and label them, one for each zone: sunlight, twilight, midnight, and abyssal. Use food coloring to dye the water in each deeper shades of blue to represent the amount of sunlight that reaches each zone. Finally, drop in a marine animal toy or fish that’s appropriate for each zone.

    6. Watch an ocean documentary

    Every streaming service is loaded with nature documentaries. Disney+ has an especially robust collection that’s perfect for kids. On Amazon, try Wildest Places or Ocean Mysteries. Netflix’s Our Planet series has episodes on coastal seas and high seas. So many options!

    Video response worksheets flat lay
    We Are Teachers

    7. Assign an ocean-themed writing prompt

    an example of a student writing prompt about ocean animals
    Adrienne Hathaway for We Are Teachers

    Use ocean-themed prompts for daily writing, journal entries, essay topics, bell ringers, or exit tickets. Some possible prompts:

    • If you were a marine animal, which zone of the ocean would you prefer to live in?
    • What would it be like to live in a coral reef?
    • Tell the story of a female sea turtle, from the time she hatches on the beach until she returns to that same beach years later to lay eggs of her own.
    • Write about a journey in a submarine to explore the deepest parts of the ocean.
    • Describe a day in the life of a marine biologist. What are they studying, and how do they go about it?

    8. Turn paint sample strips into ocean layers

    You’ll need paint sample strips in at least four deepening shades of blue; you can also add a beige color for the sandy bottom if you like. (Contact your local paint store for donations if you need more than just a few strips.) Label each paint color with one of the four zones, using deeper colors to represent deeper zones. Kids can write in descriptions of the zones, or add drawings and stickers of marine animals to each.

    Grab our free massive writing template bundle!
    We Are Teachers

    9. See ocean waves in action

    a jar of water and oil to recreate the movement of ocean waves
    Adrienne Hathaway for We Are Teachers

    Oil and water don’t mix, which makes them the perfect way to observe wave action up close. You’ll need a glass jar with a tight-fitting lid, plus water, oil, and blue food coloring. Fill the jar with water about halfway, add a few drops of food coloring, and mix. Fill the container the rest of the way with oil, getting as close to the top of the jar as possible, and put the lid on tightly. Turn the jar on its side and tilt it back and forth. Watch as the waves ripple and react to one another.

    10. Host a marine animal fair

    Let kids choose their favorite marine animal, then spend time teaching them how to research using trusted sources (see below for a list of kid-friendly ocean resources). Let them choose how they’ll present their animal—posters, dioramas, slideshows, presentations, etc. Then, set up your classroom as a “marine animal fair” and invite other classes and parents to come see what they’ve learned!

    11. Draw a life-size whale

    Did you know that blue whales are the largest creatures ever to have lived on Earth? They’re even bigger than dinosaurs! Head to the playground with some sidewalk chalk and a tape measure to measure out and draw a life-size blue whale. Kids will be astonished at the results. Find blue whale info from National Geographic here.

    12. Explore saltwater density

    one cup with salt and water and one cup with sugar and water both have grapes in the cups and only the salt water grapes are floating to demonstrate salt water density
    Adrienne Hathaway for We Are Teachers

    Use this easy ocean experiment to show that items float more easily in salt water than fresh. Fill two clear glasses with water about three-quarters of the way. Add 2 tbsp. of salt to one cup, 2 tbsp. of sugar to another, and mix thoroughly. Ask kids to predict what will happen when you drop grapes into each glass, then drop them in to see if they’re right. The grapes should float in the salt water. (Add more salt if they don’t.)

    13. Sculpt an ocean floor relief map

    Start by learning about Marie Tharp and her groundbreaking work mapping the ocean floor. (She proved plate tectonics with her meticulous work!) Then, use play dough, salt dough, or another medium to represent the depths of one or more of the world’s oceans. It’s an amazing world down there!

    14. Put together an ocean animal notebook

    an ocean animal notebook open to two pages that highlight a jellyfish fact and a seahorse fact
    Adrienne Hathaway for We Are Teachers

    Turn a blank notebook into an ocean reference manual. Draw or paste a picture of an animal on each page, then write in interesting facts about them. This is an ocean activity that will appeal to kids of any age, since you can vary the level of details you include.

    15. Discover how ocean acidification affects seashells

    One consequence of climate change is the increasing acidification of the world’s oceans. Learn why this matters so much with a simple experiment using seashells and vinegar. Add a shell to a jar, then cover it completely with vinegar. Observe what happens—before long, you’ll see carbon dioxide bubbles form as the vinegar begins to dissolve the calcium in the shell. Leave it long enough and the shell will become fragile and eventually dissolve completely.

    16. Dive into an ocean-themed sensory bin

    a sensory bin full of water and ocean animals
    Adrienne Hathaway for We Are Teachers

    Make a bigger version of an ocean in a bottle so kids can splash around a bit. Round up shells, toy sea animals, and maybe even a boat or two, then drop them into a bin of water. Every kid will enjoy splashing around while they learn!

    17. Simulate and clean up an oil spill

    Oil spills at sea are major disasters, affecting life both in the water and on land. Learn about some of the more famous oil spoils in history, then try this experiment. Fill a shallow baking dish about halfway with water. Drop in some small toy fish and sea creatures. Then, add food coloring to some oil and “spill” it into the water. Now, experiment with different methods to clean up the oil. Is it even possible to fully restore the water to its pristine condition?

    Ocean Crafts and Art Projects for Kids

    18. Download free ocean coloring pages

    colorful ocean animal coloring pages
    Adrienne Hathaway for We Are Teachers

    Our octopus, whale, and jellyfish coloring pages are perfect for when you need a quick and easy activity for kids. Keep them on hand for early finishers or use them as bell-ringer activities, or display a collection of them for a no-stress bulletin board.

    ocean coloring pages with octopus, jellyfish, and whale
    We Are Teachers

    19. Create an ocean in an egg carton

    Give each child an egg carton to paint blue like the ocean. After they’re dry, they can decorate the inside of the lid to look like a reef or sandy floor. Then, they can keep shells, rocks, or fish and marine animal toys in each compartment.

    20. Upcycle an ocean zones container

    For this ocean craft, you’ll need a tube-shaped container like an empty sanitizing-wipes tub or even a Pringles can. You’ll also need four shades of blue tissue or crepe paper: light, medium, dark, and midnight blue. Spread some glue on the container and wrap the crepe paper around it in an ombre effect, with the lightest blue at the top. Label each layer and add stickers representing the animals that live in each. Now you’ve got an upcycled storage container for your shells or ocean-themed toys.

    21. Build LEGO sea creatures

    four ocean lego animals
    Adrienne Hathaway for We Are Teachers

    Pull out the tub of LEGO and set kids free to create. The whole class can work together to set up an ocean-themed diorama, using LEGO bricks to make coral, seaweed, fish, whales, jellyfish, and more.

    22. Paint a coral reef with sponges

    Here’s another surprisingly easy ocean craft for kids. Cut disposable sponges into coral shapes, then stamp an underwater scene onto blue paper. Use markers, paint, or stickers to add fish and other marine animals to complete the picture.

    23. Illustrate inspirational ocean quotes

    Have kids choose a quote they love from our big collection of ocean quotes, then turn that quote into a poster. These make perfect hallway displays that will educate and inspire other students!

    Learn more: Ocean Quotes That Inspire Wonder

    24. Sculpt sea stars from salt dough

    Starfish, more properly known as “sea stars,” come in a wide variety of sizes and designs, but they all live in salt water. That makes salt dough the perfect medium for this ocean craft. To make it, just mix 2 cups of flour, 1 cup of salt, and 1 cup of water. Mix and knead until the dough is smooth, then store in an airtight container until you’re ready to use it.

    25. Hang paper plate jellyfish

    paper plate jellyfish ocean craft hanging on a bulletin board
    Adrienne Hathaway for We Are Teachers

    Cut paper plates in half to create the bell-shaped body of a jellyfish, and let kids paint or color them any way they life. Then, show them how to use a hole punch to create a row of holes along the bottom flat part of the bell. Tie ribbon or yarn to each hole to create dangling tentacles, then hang your ocean crafts.

    26. Make a cereal box aquarium diorama

    The hardest part of this ocean craft is trimming one large side of the box to form a frame. After that, kids can use construction paper, paint, shells, rocks, and other art supplies to create their own undersea scene. They’ll love the creative aspect of this project.

    27. Mix up ocean-themed slime

    Use one of our foolproof recipes to show kids how to make their own slime. Then, provide mix-ins like glitter, sequins, and small fish or ocean animals to add to the fun. You know they’re going to love this ocean craft!

    Learn more: How To Make Slime

    28. Put together an ocean collage

    This easy ocean craft is a great way to use up old magazines. Kids choose a specific theme, like coral reefs, deep-water creatures, beaches, marine mammals, ocean pollution, and so on. Then, they cut out and paste pictures and words that match their theme. Making collages is a simple art activity that every kid loves.

    Resources for Learning About the Ocean

    29. Ocean Books for Kids

    two examples of ocean books for kids that can be used in the classroom
    Adrienne Hathaway for We Are Teachers

    Whether you’re looking for picture books or chapter books, fiction or nonfiction, our list of terrific ocean books has got you covered!

    Learn more: Fascinating Ocean Books for Kids

    30. Ocean Facts for Kids

    Our big list of reliably sourced facts will fascinate and amaze your students! You can even download a free set of Google Slides to share in the classroom.

    Learn more: Ocean Facts for Kids

    31. Marine Life Encyclopedia

    Looking for online ocean activities? Try the Marine Life Encyclopedia. Kids will get in-depth information about all their favorite sea creatures, from sharks to otters and beyond.

    Learn more: Marine Life Encyclopedia

    32. Dive and Discover With Woods Hole

    Here’s another website full of online ocean activities. It simulates the thrill of joining actual underwater explorations, from coral reefs to deep-sea trenches.

    Learn more: Dive and Discover: Expeditions to the Sea Floor

    33. Smithsonian Ocean Life

    Just as you’d expect from the Smithsonian, this website is full of information, photos, and more ocean activities. You’ll even find free lesson plans for teachers—score!

    Learn more: Smithsonian Ocean Life

    34. NOAA for Kids

    The National Oceanic and Atmospheric Administration has a whole page full of ocean activities, articles, and videos just for kids! There’s a lot here to explore, including plenty of hands-on experiments and exploration ideas.

    Learn more: NOAA for Kids

    Don’t forget to grab your free experiment recording sheet printables!

    an image of a few science experiment worksheets for students
    We Are Teachers

    Make the most of your ocean science experiments with our free printable science experiment worksheet! Just click the button to grab your copy now.

    Plus, check out Wild Ways To Explore Animal Habitats With Kids.

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    Jill Staake, B.S., Secondary ELA Education

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  • How Genes Have Harnessed Physics to Grow Living Things

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    The original version of this story appeared in Quanta Magazine.

    Sip a glass of wine, and you will notice liquid continuously weeping down the wetted side of the glass. In 1855, James Thomson, brother of Lord Kelvin, explained in the Philosophical Magazine that these wine “tears” or “legs” result from the difference in surface tension between alcohol and water. “This fact affords an explanation of several very curious motions,” Thomson wrote. Little did he realize that the same effect, later named the Marangoni effect, might also shape how embryos develop.

    In March, a group of biophysicists in France reported that the Marangoni effect is responsible for the pivotal moment when a homogeneous blob of cells elongates and develops a head-and-tail axis — the first defining features of the organism it will become.

    The finding is part of a trend that defies the norm in biology. Typically, biologists try to characterize growth, development, and other biological processes as the result of chemical cues triggered by genetic instructions. But that picture has often seemed incomplete. Researchers now increasingly appreciate the role of mechanical forces in biology: forces that push and pull tissues in response to their material properties, steering growth and development in ways that genes cannot.

    Modern imaging and measurement techniques have opened scientists’ eyes to these forces by flooding the field with data that invites mechanical interpretations. “What has changed over the past decades is really the possibility to watch what happens live, and to see the mechanics in terms of cell movement, cell rearrangement, tissue growth,” said Pierre-François Lenne of Aix Marseille University, one of the researchers behind the recent study.

    The shift toward mechanical explanations has revived interest in pre-genetic models of biology. For example, in 1917 the Scottish biologist, mathematician, and classics scholar D’Arcy Thompson published On Growth and Form, which highlighted similarities between the shapes found among living organisms and those that emerge in nonliving matter. Thompson wrote the book as an antidote to what he thought was an excessive tendency to explain everything in terms of Darwinian natural selection. His thesis—that physics, too, shapes us—is coming back into vogue.

    Time-lapse movie of a gastruloid developing a head-to-tail axis.

    Video: Sham Tlili/CNRS

    “The hypothesis is that physics and mechanics can help us understand the biology at the tissue scale,” said Alexandre Kabla, a physicist and engineer at the University of Cambridge.

    The task now is to understand the interplay of causes, where genes and physics somehow act hand in hand to sculpt organisms.

    Grow With the Flow

    Mechanical models of embryo and tissue growth are not new, but biologists long lacked ways of testing these ideas. Just seeing embryos is difficult; they are small and diffusive, bouncing light in all directions like frosted glass. But new microscopy and image analysis techniques have opened a clearer window on development.

    Lenne and his coworkers applied some of the new techniques to observe the motion of cells inside mouse gastruloids: bundles of stem cells that, as they grow, mimic the early stages of embryo growth.

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    Anna Demming

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  • James Watson, co-discoverer of the double-helix shape of DNA, has died at age 97

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    James D. Watson, whose co-discovery of the twisted-ladder structure of DNA in 1953 helped light the long fuse on a revolution in medicine, crimefighting, genealogy and ethics, has died. He was 97.

    The breakthrough — made when the brash, Chicago-born Watson was just 24 — turned him into a hallowed figure in the world of science for decades. But near the end of his life, he faced condemnation and professional censure for offensive remarks, including saying Black people are less intelligent than white people.

    Watson shared a 1962 Nobel Prize with Francis Crick and Maurice Wilkins for discovering that deoxyribonucleic acid, or DNA, is a double helix, consisting of two strands that coil around each other to create what resembles a long, gently twisting ladder.

    That realization was a breakthrough. It instantly suggested how hereditary information is stored and how cells duplicate their DNA when they divide. The duplication begins with the two strands of DNA pulling apart like a zipper.

    Even among non-scientists, the double helix would become an instantly recognized symbol of science, showing up in such places as the work of Salvador Dali and a British postage stamp.

    The discovery helped open the door to more recent developments such as tinkering with the genetic makeup of living things, treating disease by inserting genes into patients, identifying human remains and criminal suspects from DNA samples, and tracing family trees and ancient human ancestors. But it has also raised a host of ethical questions, such as whether we should be altering the body’s blueprint for cosmetic reasons or in a way that is transmitted to a person’s offspring.

    “Francis Crick and I made the discovery of the century, that was pretty clear,” Watson once said. He later wrote: “There was no way we could have foreseen the explosive impact of the double helix on science and society.”

    Watson never made another lab finding that big. But in the decades that followed, he wrote influential textbooks and a best-selling memoir and helped guide the project to map the human genome. He picked out bright young scientists and helped them. And he used his prestige and contacts to influence science policy.

    Watson died in hospice care after a brief illness, his son said Friday. His former research lab confirmed he passed away a day earlier.

    “He never stopped fighting for people who were suffering from disease,” Duncan Watson said of his father.

    Watson’s initial motivation for supporting the gene project was personal: His son Rufus had been hospitalized with a possible diagnosis of schizophrenia, and Watson figured that knowing the complete makeup of DNA would be crucial for understanding that disease — maybe in time to help his son.

    He gained unwelcome attention in 2007, when the Sunday Times Magazine of London quoted him as saying he was “inherently gloomy about the prospect of Africa” because “all our social policies are based on the fact that their intelligence is the same as ours — where all the testing says not really.” He said that while he hopes everyone is equal, “people who have to deal with Black employees find this is not true.”

    He apologized, but after an international furor he was suspended from his job as chancellor of the prestigious Cold Spring Harbor Laboratory in New York. He retired a week later. He had served in various leadership jobs there for nearly 40 years.

    In a television documentary that aired in early 2019, Watson was asked if his views had changed. “No, not at all,” he said. In response, the Cold Spring Harbor lab revoked several honorary titles it had given Watson, saying his statements were “reprehensible” and “unsupported by science.”

    Watson’s combination of scientific achievement and controversial remarks created a complicated legacy.

    He has shown “a regrettable tendency toward inflammatory and offensive remarks, especially late in his career,” Dr. Francis Collins, then-director of the National Institutes of Health, said in 2019. “His outbursts, particularly when they reflected on race, were both profoundly misguided and deeply hurtful. I only wish that Jim’s views on society and humanity could have matched his brilliant scientific insights.”

    Long before that, Watson scorned political correctness.

    “A goodly number of scientists are not only narrow-minded and dull, but also just stupid,” he wrote in “The Double Helix,” his bestselling 1968 book about the DNA discovery.

    For success in science, he wrote: “You have to avoid dumb people. … Never do anything that bores you. … If you can’t stand to be with your real peers (including scientific competitors) get out of science. … To make a huge success, a scientist has to be prepared to get into deep trouble.”

    It was in the fall of 1951 that the tall, skinny Watson — already the holder of a Ph.D. at 23 — arrived at Britain’s Cambridge University, where he met Crick. As a Watson biographer later said, “It was intellectual love at first sight.”

    Crick himself wrote that the partnership thrived in part because the two men shared “a certain youthful arrogance, a ruthlessness, and an impatience with sloppy thinking.”

    Together they sought to tackle the structure of DNA, aided by X-ray research by colleague Rosalind Franklin and her graduate student Raymond Gosling. Watson was later criticized for a disparaging portrayal of Franklin in “The Double Helix,” and today she is considered a prominent example of a female scientist whose contributions were overlooked. (She died in 1958.)

    Watson and Crick built Tinker Toy-like models to work out the molecule’s structure. One Saturday morning in 1953, after fiddling with bits of cardboard he had carefully cut to represent fragments of the DNA molecule, Watson suddenly realized how these pieces could form the “rungs” of a double helix ladder.

    His first reaction: “It’s so beautiful.”

    Figuring out the double helix “goes down as one of the three most important discoveries in the history of biology,” alongside Charles Darwin’s theory of evolution through natural selection and Gregor Mendel’s fundamental laws of genetics, said Cold Spring Harbor lab’s president, Bruce Stillman.

    Following the discovery, Watson spent two years at the California Institute of Technology, then joined the faculty at Harvard in 1955. Before leaving Harvard in 1976, he essentially created the university’s program for molecular biology, scientist Mark Ptashne recalled in a 1999 interview.

    Watson became director of the Cold Spring Harbor lab in 1968, its president in 1994 and its chancellor 10 years later. He made the lab on Long Island an educational center for scientists and non-scientists, focused research on cancer, instilled a sense of excitement and raised huge amounts of money.

    He transformed the lab into a “vibrant, incredibly important center,” Ptashne said. It was “one of the miracles of Jim: a more disheveled, less smooth, less typically ingratiating person you could hardly imagine.”

    From 1988 to 1992, Watson directed the federal effort to identify the detailed makeup of human DNA. He created the project’s huge investment in ethics research by simply announcing it at a news conference. He later said it was “probably the wisest thing I’ve done over the past decade.”

    Watson was on hand at the White House in 2000 for the announcement that the federal project had completed an important goal: a “working draft” of the human genome, basically a road map to an estimated 90 percent of human genes.

    Researchers presented Watson with the detailed description of his own genome in 2007. It was one of the first genomes of an individual to be deciphered.

    Watson knew that genetic research could produce findings that make some people uncomfortable. In 2007, he wrote that when scientists identify genetic variants that predispose people to crime or significantly affect intelligence, the findings should be publicized rather than squelched out of political correctness.

    James Dewey Watson was born in Chicago on April 6, 1928, into “a family that believed in books, birds and the Democratic Party,” as he put it. From his birdwatcher father he inherited an interest in ornithology and a distaste for explanations that didn’t rely on reason or science.

    Watson was a precocious child who loved to read, studying books like “The World Telegraph Almanac of Facts.” He entered the University of Chicago on a scholarship at 15, graduated at 19 and earned his doctorate in zoology at Indiana University three years later.

    He got interested in genetics at age 17 when he read a book that said genes were the essence of life.

    “I thought, ‘Well, if the gene is the essence of life, I want to know more about it,’” he later recalled. “And that was fateful because, otherwise, I would have spent my life studying birds and no one would have heard of me.”

    At the time, it wasn’t clear that genes were made of DNA, at least for any life form other than bacteria. But Watson went to Europe to study the biochemistry of nucleic acids like DNA. At a conference in Italy, Watson saw an X-ray image that indicated DNA could form crystals.

    “Suddenly I was excited about chemistry,” Watson wrote in “The Double Helix.” If genes could crystallize, “they must have a regular structure that could be solved in a straightforward fashion.”

    “A potential key to the secret of life was impossible to push out of my mind,” he recalled.

    In the decades after his discovery, Watson’s fame persisted. Apple Computer used his picture in an ad campaign. At conferences, graduate students who weren’t even born when he worked at Cambridge nudged each other and whispered, “There’s Watson. There’s Watson.” They got him to autograph napkins or copies of “The Double Helix.”

    A reporter asked him 2018 if any building at the Cold Spring Harbor lab was named after him. No, Watson replied, “I don’t need a building named after me. I have the double helix.”

    His 2007 remarks on race were not the first time Watson struck a nerve with his comments. In a speech in 2000, he suggested that sex drive is related to skin color. And earlier he told a newspaper that if a gene governing sexuality were found and could be detected in the womb, a woman who didn’t want to have a gay child should be allowed to have an abortion.

    More than a half-century after winning the Nobel, Watson put the gold medal up for auction in 2014. The winning bid, $4.7 million, set a record for a Nobel. The medal was eventually returned to Watson.

    Both of Watson’s Nobel co-winners, Crick and Wilkins, died in 2004.

    ___

    Ritter is a retired AP science writer. AP science writers Christina Larson in Washington and Adithi Ramakrishnan in New York contributed to this report.

    ___

    The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.

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  • James Watson helped crack DNA’s code, sparking medical advances and ethical debates

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    On a foggy Saturday morning in 1953, a tall, skinny 24-year-old man fiddled with shapes he had cut out of cardboard. They represented fragments of a DNA molecule, and young James Watson was trying to figure how they fit together in a way that let DNA do its job as the stuff of genes.

    Suddenly, he realized that they joined together to form the “rungs” of a long, twisted ladder, a shape better known nowadays as a double helix.

    His first reaction: “It’s so beautiful.”

    But it was more than that. Discovering the structure of deoxyribonucleic acid, or DNA, was a breakthrough that would help open the way to a revolution in medicine, biology and other fields as diverse as crime-fighting, genealogy and ethics.

    Watson died Thursday, according to his former research lab. The Chicago-born scientist was 97 years old. His career was marked by significant achievements, including his role in mapping the human genome. However, his legacy is complicated by controversial remarks on race, which led to his condemnation and loss of honorary titles.

    Figuring out the double helix “goes down as one of the three most important discoveries in the history of biology,” alongside Charles Darwin’s theory of evolution through natural selection and Gregor Mendel’s fundamental laws of genetics, said Bruce Stillman, president of the Cold Spring Harbor lab, on Friday.

    Watson shared the Nobel Prize with collaborator Francis Crick and scientist Maurice Wilkins. They were aided by X-ray research by colleague Rosalind Franklin and her graduate student Raymond Gosling. Watson was later criticized for a disparaging portrayal of Franklin in his book “The Double Helix,” and today she is considered a prominent example of a female scientist whose contributions were overlooked.

    Both of his Nobel co-winners, Crick and Wilkins, died in 2004. Franklin died in 1958.

    Their discovery instantly suggested how hereditary information is stored and how a cell duplicates its DNA before dividing so that each resulting cell inherits a copy. The duplication begins with the two strands of DNA pulling apart like a zipper.

    “Francis Crick and I made the discovery of the century, that was pretty clear,” Watson once said. He also wrote: “There was no way we could have foreseen the explosive impact of the double helix on science and society.”

    Among non-scientists, the double helix has become an instantly recognized symbol of science. And for researchers, it helped open the door to more recent developments such as tinkering with the genetic makeup of living things, treating disease by inserting genes into patients, identifying human remains and criminal suspects from DNA samples and tracing family trees.

    That in turn has raised a host of ethical questions, such as whether we should be altering a person’s genome in a way that is transmitted to one’s offspring.

    Watson’s initial motivation for supporting the gene project was personal: His son Rufus had been hospitalized with a possible diagnosis of schizophrenia, and Watson figured that knowing the complete makeup of DNA would be crucial for understanding that disease, maybe in time to help his son.

    Watson never made another lab finding as big as the double helix. But in the decades that followed, he wrote influential textbooks and a best-selling memoir, picked out bright young scientists and helped them. And he used his prestige and contacts to influence science policy.

    Following the discovery, Watson spent two years at the California Institute of Technology, then joined the faculty at Harvard in 1955. Before leaving Harvard in 1976, he essentially created the university’s molecular biology program, scientist Mark Ptashne recalled in a 1999 interview. Watson became director of the Cold Spring Harbor lab in 1968, its president in 1994 and its chancellor 10 years later.

    From 1988 to 1992, he directed the federal effort to identify the detailed makeup of human DNA. He created the project’s huge investment in ethics research by simply announcing it at a news conference. He later said it was “probably the wisest thing I’ve done over the past decade.”

    Yet he gained unwelcome attention in 2007 when the Sunday Times Magazine of London quoted him as saying he was “inherently gloomy about the prospect of Africa” because “all our social policies are based on the fact that their intelligence is the same as ours — where all the testing says not really.” He said that while he hopes everyone is equal, “people who have to deal with Black employees find this is not true.”

    He apologized, but after an international furor he was suspended from his job as chancellor of the Cold Spring Harbor Laboratory in New York. He retired a week later. He had served in various leadership jobs there for nearly 40 years.

    “I only wish that Jim’s views on society and humanity could have matched his brilliant scientific insights.” Dr. Francis Collins, then-director of the National Institutes of Health, said in 2019.

    In a television documentary that year, Watson was asked if his views had changed. “No, not at all,” he said.

    In response, the Cold Spring Harbor lab revoked several honorary titles it had given Watson, saying his statements were “reprehensible” and “unsupported by science.”

    His 2007 remarks on race were not the first time Watson struck a nerve with his comments. In a speech in 2000, he suggested that sex drive is related to skin color. And earlier he told a newspaper that if a gene governing sexuality were found and could be detected in the womb, a woman who didn’t want to have a gay child should be allowed to have an abortion.

    ___

    Ritter is a retired AP science writer. AP science writers Christina Larson in Washington and Adithi Ramakrishnan in New York contributed to this report.

    ___

    The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.

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  • Zuckerberg, Chan shift bulk of philanthropy to science, focusing on AI and biology to curb disease

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    By BARBARA ORTUTAY

    REDWOOD CITY, Calif. (AP) — For the past decade, Dr. Priscilla Chan and her husband Mark Zuckerberg have focused part of their philanthropy on a lofty goal — “to cure, prevent or manage all disease” — if not in their lifetime, then in their children’s. But during that time, they also funded underprivileged schools, immigration reform and efforts around diversity, equity and inclusion.

On Thursday, Chan and Zuckerberg also announced that Biohub has hired the team at EvolutionaryScale, an AI research lab that has created large-scale AI systems for the life sciences. Alex Rives, EvolutionaryScale’s co-founder, will serve as Biohub’s head of science, leading research efforts on experimental biology, data and artificial intelligence. The financial terms were not disclosed.

Biohub’s ambition for the next years and decades is to create virtual cell systems that would not have been possible without recent advances in AI. Similar to how large language models learn from vast databases of digital books, online writings and other media, its researchers and scientists are working toward building virtual systems that serve as digital representations of human physiology on all levels, such as molecular, cellular or genome. As it is open source — free and publicly available — scientists can then conduct virtual experiments on a scale not possible in physical laboratories.

Noting that Biohub launched when the couple had their first child, Chan listed off some of the organization’s accomplishments, ranging from building the largest single-cell data set, contributing to one of the largest human cell maps, building sensors to measure inflammation in real-time in living cells and researching rare diseases.

That work continues, with a focus on using AI to advance biomedical research.

“And to anchor it back onto the impact on patients, you know, why do this?” Chan said. “It’s like, why is a virtual cell important? We have cured diseases for mice and for flies and for zebrafish, many, many times. And that’s great. But we want to make sure that we are actually using biology to push the forefront of medicine for people — and that is so promising.”

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  • Don’t Let the Fuzzy Rats Win: Tips from a Squirrel Hater Who’s Seen It All

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    Squirrels: Are they just rats with better PR? Be advised that this is not safe reading material for squirrel lovers, or even squirrel apologists. In my opinion, squirrels are worse than rats—smarter, more devious, more destructive. I’ve had them nest in my chimney, chew holes in my eaves to get into my walls, and destroy multiple bird feeders. I even had one chew through an entire 4-by-2 pergola rafter to get at a suet block.

    With the popularity of smart bird feeders, it’s even more important to learn ways to keep them out of your yard, lest they turn your investment into a pile of chewed-up plastic bits. To make matters worse, if you live on the West Coast like I do, you’re likely to be dealing with the Eastern gray squirrel, which is a nonnative, invasive species that competes for resources with native species like Western gray squirrels. What’s a backyard bird enthusiast to do?

    Lucky for you, I’ve been feeding birds for almost 25 years across three different states, and have been testing smart feeders for the past year, fighting near-daily battles with these furry neighborhood foes. I’ve tried it all and found out what works—and what doesn’t—so you can keep your sanity intact.

    For more birdy business, check out our guides to the Best Smart Bird Feeders, the Best Binoculars, and the Best Gifts for Bird Lovers.

    The Golden (5-7-9) Rule

    Photograph: Kat Merck

    OnlyFly

    Bird Feeder Pole Stand

    First off, there is a tried-and-true method of foiling squirrels, and it’s both free and harmless. Experts refer to it as the 5-7-9 Rule: Keep your feeder at least 5 feet off the ground, 7 feet away from structures like houses, trees, or fences; and 9 feet away from anything overhead that they could jump from, such as a tree branch or roof. This usually means putting your feeder on a pole with a baffle (I use the set above), or hanging it from a tall shepherd’s hook.

    If you’re in the market for a bird feeder, especially a smart feeder, it’s imperative that it have the option to hang or be pole-mounted, because if you can only mount it on a fence or a tree, you’re essentially rolling out the welcome mat for squirrels. (All the smart feeders I recommend, including Birdfy and Bird Buddy, include pole mounts.) If you want to go the extra mile, you can also grease your pole with Crisco, which doesn’t last long but is good for an entertaining day or two.

    Note that if your smart feeder doesn’t have an attached solar panel to charge the battery, you likely won’t be able to mount it on the pole with the feeder without some jury-rigging, so I recommend going for a model with a built-in solar roof or no solar panel at all.

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    Kat Merck

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  • Jona Health’s Mail-Order Kit Helps You Decode Your Microbiome

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    Look, there’s nothing quite like starting your day by pooping on a little paper hammock affixed to your toilet seat and then poking it a bunch of times with a cotton swab. It was more of a mental hurdle than a practical one, though, as the collection and disposal (you just flush the hammock down when you’re done) was easy enough. You then swish the stick around in a solution, cap it, and send it off. Twenty days later, I got an email that my results were in.

    On the website, your results are broken down into a few sections: Summary (with tabs for Brain Health, GI Health, Metabolic Health, Skin Health, and Physical Performance), Action Plan (with tabs for Highest Impact, Diet, Lifestyle, and Probiotics), and the Organisms page, which shows you every single organism it found in your sample, and their relative abundance. Mine held some surprises.

    On the positive side, my Microbiome Diversity came in at 4.19, which is above average (normal range is 2.80–3.99, as measured by the Shannon Index), which it says is a sign of a healthy microbiome, and it didn’t find any pathogens or parasites. It says I digest lactose well (thank goodness). It didn’t find any associations for things like depression, celiac disease, IBS, ulcerative colitis, leaky gut, hypertension, eczema, or a bunch of other things that I’m thankful to not have. Some of these were actually a bit puzzling, frankly, as I’ve struggled with insomnia pretty much my entire life, but it didn’t find any associations there, or for fatigue, and I am most assuredly a tired human.

    As far as associations that it did find, some were things I suspected, while others were total surprises. Under Brain Health, I had a moderate association for stress and a low association for ADHD, neither of which shocked me. Under Metabolic health was a “very low” association for prediabetes, which I actually thought would be higher, unfortunately. I had a moderate association with osteoarthritis, which made sense, given my family history.

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    Brent Rose

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  • Trio Wins Nobel Prize in Medicine for Discoveries on Immune System

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    Immunologists Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi were awarded the Nobel Prize in Physiology or Medicine for discoveries that spurred the development of new treatments for cancer and autoimmune diseases and laid the foundation for a new field of research.

    The trio identified a core feature of how the immune system functions and keeps itself in-check: regulatory T-cells. They prevent other immune cells from attacking our own bodies and developing autoimmune conditions including Type 1 diabetes and rheumatoid arthritis. Based on this fundamental knowledge, clinical trials are ongoing to test therapies for autoimmune diseases, cancer and following organ transplantation.

    Copyright ©2025 Dow Jones & Company, Inc. All Rights Reserved. 87990cbe856818d5eddac44c7b1cdeb8

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    Brianna Abbott

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  • What Is Thirst?

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    “There are only a couple of things that are so important for your body that there’s a completely innate drive to get it if you fall into deficiency,” Knight said. “Oxygen, food, water, and sodium.”

    However, animals like us do not experience salt desire as a powerful, controlling drive as we do with oxygen, food, and water. Sensors signal salt levels to the brain; in addition to the OVLT and SFO, sensors in the heart detect the stretching of atria and ventricles. But there is no analogous salt pang when we need it, the way a stomach churns for food or a scratchy throat cries out for water. Instead, the need to consume salt is mediated by taste and the brain’s reward pathways. “The taste of salt is bimodal,” Knight said. “It tastes good at low doses; at high doses it tastes disgusting, like drinking seawater.”

    Imagine the urge to eat a big bag of potato chips. If the body needs salt, those chips will cause a surge of pleasurable dopamine to flood the brain. If the body doesn’t need salt, that dopamine drip disappears. “It’s pretty much reinforcement learning,” said Yuki Oka, a neurobiologist at the California Institute of Technology who studies how the body maintains homeostasis. “More dopamine means a repeated behavior.”

    Everyone Thirsts Differently

    Scientists monitoring a river collect data and then have a choice about whether to act on their findings. Similarly, just because the brain measures the blood’s sodium levels doesn’t mean it has to act on that information.

    Take Elena Gracheva’s thirteen-lined ground squirrels. Gracheva, a neurophysiologist at the Yale School of Medicine, studies these rodents, native to North American grasslands, to understand how specific brain regions control thirst. The thirteen-lined ground squirrel is an ideal model for this, she said, because it hibernates for more than half the year, without eating or drinking. “They’re like monks,” Gracheva said. “They don’t go outside for eight months. They don’t have water in their underground burrow.” How do they not get thirsty?

    Elena Gracheva (left) has traced how the brains of thirteen-lined ground squirrels (right) suppress their thirst response during many months of hibernation.

    Courtesy of Gracheva Lab

    Squirrel grass and leaf

    CC-BY 2.0 via Wikimedia Commons

    It isn’t that the squirrels don’t need water. They do. Their bodies cry out for it. But according to Gracheva’s research, during hibernation their brain ignores the body’s signals.

    In mammals, a drop in blood water levels (which means a simultaneous rise in salt concentration, all things being equal) triggers two coupled processes. The hypothalamus pumps out the hormone vasopressin, which tells the kidneys to retain water rather than let it out as urine, and the SFO kicks off the thirst drive to direct the animal to drink. However, while ground squirrels are hibernating, their vasopressin levels jump, but the animal still doesn’t drink. “The circuit for vasopressin was normal, but thirst neurons were downregulated,” Gracheva said. “These two pathways are uncoupled.” The body is trying to retain the water it has but does not act to consume more.

    The logic of the disrupted circuitry is extremely powerful. “Even if you wake them up in the middle of hibernation, they’re not going to drink,” Gracheva said.

    The underlying network that Gracheva studies in squirrels is universal in mammals, up to and including humans. But that same neurological logic doesn’t lead to the same behaviors. Humans drink a glass of water when they’re thirsty. Cats and rabbits mostly get water from the food they eat. Camels can burn their fat stores for water (which produces carbon dioxide and water), but they also consume gallons of it and store it in their stomachs for when they need it later. Sea otters can drink ocean water and excrete urine that is saltier than the water they swim in; they are the only marine mammals to actively do this.

    How each animal manages water and salt is specialized to its ecosystem, lifestyle, and selective pressures. The question “What does it mean to be thirsty?” has no one answer. We each thirst in our own way.


    Original story reprinted with permission from Quanta Magazine, an editorially independent publication of the Simons Foundation whose mission is to enhance public understanding of science by covering research developments and trends in mathematics and the physical and life sciences.

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    Dan Samorodnitsky

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  • Hungry Worms Could Help Solve Plastic Pollution

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    Plastics that support modern life are inexpensive, strong, and versatile, but are difficult to dispose of and have a serious impact when released into the environment. Polyethylene, in particular, is the most widely produced plastic in the world, with more than 100 million tons distributed annually. Since it can take decades to decompose—and along the way can harm wildlife and degrade into harmful microplastics—its disposal is an urgent issue for mankind.

    In 2017, European researchers discovered a potential solution. The larvae of wax moths, commonly known as wax worms, have the ability to break down polyethylene in their bodies. Wax worms have been considered a pest since ancient times because they parasitize beehives, feeding on beeswax. However, we now know that they also spontaneously feed on polyethylene, which has a chemically similar structure.

    “Around 2,000 wax worms can break down an entire polyethylene bag in as little as 24 hours, although we believe that co-supplementation with feeding stimulants like sugars can reduce the number of worms considerably,” said Dr Bryan Cassone, a professor of biology at Brandon University in Canada, in a news release. Cassone and his team have been researching how these insects could be harnessed to help combat plastic pollution. “Understanding the biological mechanisms and consequences on fitness associated with plastic biodegradation is key to using wax worms for large-scale plastic remediation,” he says.

    In previous experiments, Cassone and his team found out exactly how wax worms break down polyethylene. To understand their digestive mechanism, Cassone’s team fed polyethylene to wax worms for several days and followed the insects’ metabolic processes and changes in their gut environment. They found that as the wax worms ate the polyethylene, their feces liquefied and contained glycol as a byproduct.

    But when the insects’ intestinal bacteria were suppressed by administering antibiotics, the amount of glycol in their feces was greatly reduced. This revealed that the breaking down of polyethylene is dependent on the wax worms’ gut microbes.

    The team also isolated bacteria from the guts of wax worms and then cultured strains that could survive on polyethylene as their sole food source. Among them was a strain of Acinetobacter, which survived for more than a year in the laboratory environment and continued to break down polyethylene. This revealed how robust and persistent the wax worm’s gut flora is in its ability to break down plastics.

    Yet in reality, when it comes to consuming plastic, gut bacteria are not working alone. When the researchers conducted genetic analysis on the insects, they found that plastic-fed wax worms showed increased gene expression relating to fat metabolism, and after being fed plastic, the wax worms duly showed signs of having increased body fat. Armed with their plastic-digesting gut bacteria, the larvae can break down plastics and convert them into lipids, which they then store in their bodies.

    However, a plastic-only diet didn’t result in wax worms’ long-term survival. In their latest experiment, the team found that wax worms that continued to eat only polyethylene died within a few days and lost a great deal of weight. This showed that it is difficult for wax worms to continually process polyethylene waste. But researchers believe that creating a food source to assist their intake of polyethylene would mean wax worms are able to sustain healthy viability on a plastic diet and improve their decomposition efficiency.

    Looking ahead, the team suggests two strategies for using the wax worm’s ability to consume plastics. One is to mass produce wax worms that are fed on a polyethylene diet, while providing them with the nutritional support they need for long-term survival, and then integrating them into the circular economy, using the insects themselves to dispose of waste plastic. The other is to redesign the plastic degradation pathway of wax worms in the lab, using only microorganisms and enzymes, and so create a means of disposing of plastic that doesn’t need the actual insects.

    In the insect-rearing route, a byproduct would be large amounts of insect biomass—countless larvae that have been fed on plastic. These could potentially be turned into a highly nutritious feed for the aquaculture industry, as according to the research team’s data, the insects could be a good source of protein for commercial fish.

    This story originally appeared on WIRED Japan and has been translated from Japanese.

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    Ritsuko Kawai

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  • These Newly Discovered Cells Breathe in Two Ways

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    The team members went through a process of incrementally determining what elements and molecules the bacterial strain could grow on. They already knew it could use oxygen, so they tested other combinations in the lab. When oxygen was absent, RSW1 could process hydrogen gas and elemental sulfur—chemicals it would find spewing from a volcanic vent—and create hydrogen sulfide as a product. Yet while the cells were technically alive in this state, they didn’t grow or replicate. They were making a small amount of energy—just enough to stay alive, nothing more. “The cell was just sitting there spinning its wheels without getting any real metabolic or biomass gain out of it,” Boyd said.

    Then the team added oxygen back into the mix. As expected, the bacteria grew faster. But, to the researchers’ surprise, RSW1 also still produced hydrogen sulfide gas, as if it were anaerobically respiring. In fact, the bacteria seemed to be breathing both aerobically and anaerobically at once, and benefiting from the energy of both processes. This double respiration went further than the earlier reports: The cell wasn’t just producing sulfide in the presence of oxygen but was also performing both conflicting processes at the same time. Bacteria simply shouldn’t be able to do that.

    “That set us down this path of ‘OK, what the heck’s really going on here?’” Boyd said.

    Breathing Two Ways

    RSW1 appears to have a hybrid metabolism, running an anaerobic sulfur-based mode at the same time it runs an aerobic one using oxygen.

    “For an organism to be able to bridge both those metabolisms is very unique,” said Ranjani Murali, an environmental microbiologist at the University of Nevada, Las Vegas, who was not involved in the research. Normally when anaerobic organisms are exposed to oxygen, damaging molecules known as reactive oxygen compounds create stress, she said. “For that not to happen is really interesting.”

    In the thermal spring Roadside West (left) in Yellowstone National Park, researchers isolated an unusual microbe from the gray-colored biofilm (right).

    Photograph: Eric Boyd; Quanta Magazine

    In the thermal spring Roadside West  in Yellowstone National Park researchers isolated an unusual microbe from the...

    In the thermal spring Roadside West (left) in Yellowstone National Park, researchers isolated an unusual microbe from the gray-colored biofilm (right).Photograph: Eric Boyd; Quanta Magazine

    Boyd’s team observed that the bacteria grew best when running both metabolisms simultaneously. It may be an advantage in its unique environment: Oxygen isn’t evenly distributed in hot springs like those where RSW1 lives. In constantly changing conditions, where you could be bathed in oxygen one moment only for it to disappear, hedging one’s metabolic bets might be a highly adaptive trait.

    Other microbes have been observed breathing two ways at once: anaerobically with nitrate and aerobically with oxygen. But those processes use entirely different chemical pathways, and when paired together, they tend to present an energetic cost to the microbes. In contrast, RSW1’s hybrid sulfur/oxygen metabolism bolsters the cells instead of dragging them down.

    This kind of dual respiration may have evaded detection until now because it was considered impossible. “You have really no reason to look” for something like this, Boyd said. Additionally, oxygen and sulfide react with each other quickly; unless you were watching for sulfide as a byproduct, you might miss it entirely, he added.

    It’s possible, in fact, that microbes with dual metabolisms are widespread, Murali said. She pointed to the many habitats and organisms that exist at tenuous gradients between oxygen-rich and oxygen-free areas. One example is in submerged sediments, which can harbor cable bacteria. These elongated microbes orient themselves in such a way that one end of their bodies can use aerobic respiration in oxygenated water while the other end is buried deep in anoxic sediment and uses anaerobic respiration. Cable bacteria thrive in their precarious partition by physically separating their aerobic and anaerobic processes. But RSW1 appears to multitask while tumbling around in the roiling spring.

    It’s still unknown how RSW1 bacteria manage to protect their anaerobic machinery from oxygen. Murali speculated that the cells might create chemical supercomplexes within themselves that can surround, isolate and “scavenge” oxygen, she said—using it up quickly once they encounter it so there is no chance for the gas to interfere with the sulfur-based breathing.

    RSW1 and any other microbes that have dual metabolism make intriguing models for how microbial life may have evolved during the Great Oxygenation Event, Boyd said. “That must have been a quite chaotic time for microbes on the planet,” he said. As a slow drip of oxygen filtered into the atmosphere and sea, any life-form that could handle an occasional brush with the new, poisonous gas—or even use it to its energetic benefit—may have been at an advantage. In that time of transition, two metabolisms may have been better than one.


    Original story reprinted with permission from Quanta Magazine, an editorially independent publication of the Simons Foundation whose mission is to enhance public understanding of science by covering research developments and trends in mathematics and the physical and life sciences.

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    Jake Buehler

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  • What It’s Like Watching Dozens of Bodies Decompose (for Science)

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    Somewhere out in the countryside, hidden behind a copse of trees, are fields full of dead human bodies. These corpses have been strategically laid out in rows, naked as the day they were born, and left to the mercy of the elements until all that’s left of them are bones.

    It sounds like a scene out of a horror film, but these places are real. They’re called taphonomic research facilities, or sometimes “body farms”—sites where forensic scientists study how the human body decomposes. (Don’t worry, the bodies are all donated.) By observing how fast cadavers break down in a controlled setting, investigators can learn more about decomposition and better pinpoint exactly what happened to dead bodies that are found in the real world.

    There are only a handful of body farms in existence, and most are in the US. Employees spend their days answering emails, cleaning bones, and leaving corpses out in the sun. WIRED spoke to one researcher and instructor in the US about their job—the good, the gross, and the pungent.

    It makes me laugh on TV shows where they’re like, “Oh, well, this body was here for exactly three months.” Decomposition is such an individualized process for each donor. It depends on the person’s size, were they taking illicit drugs, were they undergoing chemo-therapy or radiation at the time? Cancer treatments will limit certain scavengers coming to the body, because those remains are going to smell different to those animals. I have placed donors next to each other at the same time, who could have died within days of each other, and one is going to skeletonize faster than the other. One might mummify. It is just such an individual process. Each donor teaches us something different about decomposition, contributing to our understanding of how the body breaks down with time, seasonality, temperature, and body composition. But that doesn’t make good TV.

    We took more than 40 bodies into our care last year, and more than 50 in 2023. But more typical for us is 20 to 30 donors in a year. When a body arrives, we take photos, we take DNA swabs, if they consented to that when they were alive. And then we find a place for them.

    Most of our donors will go out to our outdoor surface enclosure, where they are laid out unclothed, just on the ground. The enclosure follows the natural topography of the area and is double-fenced. We have some PVC and chicken-wire cages that we place over the remains at some point, to limit scavenging. We did recently have some turkey vultures that wiggled themselves under the cages and got caught. We also usually have several donors that we will bury in the natural soil within another enclosure. Those are only exhumed after several years, when they are expected to be skeletonized.

    We run classes at least twice a year, for our law enforcement and fire investigator partners. Donors who have consented to trauma research will be placed in a room that is set alight. We’ll let the donors cool for two days, and then the investigators practice moving a body to look for evidence that might have been shielded under a body and preserved. We also track the damage to the bodies, like how bones broke, and that can be really helpful for crime scene investigations.

    Forensic anthropology in the US is becoming more female-dominated. Most of our students are female. Those of us running these facilities are mostly female. It is probably like a 9:1 ratio of women to men amongst our students here. We get drivers that are bringing donors to us that are like, “Oh, who are all these ladies?” We are not here for you to ogle at, we are scientists!

    We are always checking in with our students, because sometimes it’s hard to see a person go through that decomposition process. Or, when we get a new donor, we don’t know necessarily what we’ll find when we remove that sheet or open that body bag. I’ve only had one student who changed majors after being at our facility, though. Most of them thought they’d be the ones puking or passing out, and they’re not.

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    Jess Thomson

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  • Florida researchers capture Burmese python swallowing grown deer whole

    Florida researchers capture Burmese python swallowing grown deer whole

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    According to a new study published in the journal Reptiles and Amphibians, Burmese pythons can consume prey even larger than scientists realized.See the story in the video aboveThis means that more animals are on the menu across southern Florida, where the non-native, invasive snakes have decimated populations of foxes, bobcats, raccoons and other animals.Pythons swallow deer, alligators and other prey whole. What they can eat is limited to and dependent on how big the Burmese python’s mouth can stretch. Researchers call this the snake’s gape.Conservancy of Southwest Florida biologists Ian Bartoszek and Ian Easterling recently conducted a study with Dr. Bruce Jayne from the Department of Biological Science at the University of Cincinnati to better understand the ecological impacts of the invasive species.The team measured the greatest maximum gape recorded in Burmese pythons to date.Professor Jayne said measurements of the longest Burmese python, 19 feet, and two other very large snakes, 15 and 17 feet, captured in Florida show that pythons have a gape bigger than previous mathematical models suggest.The largest Burmese python ever captured in Florida weighed a record 215 pounds, stretching 17.7 feet long.Previous studies of pythons found the largest gape diameter was 8.7 inches, but the snakes in the current study had a maximal gape of 10.2 inches. These measurements equate to a circumference of 32 inches.Three large adult female Burmese pythons researched at the conservancy were examined and used for data and observations of this study, including the longest documented capture on record.One python measured for data was found by conservancy biologists while it was ingesting a 77-pound white-tailed deer. The deer was 66.9% of the snake’s mass.“Watching an invasive apex predator swallow a full-sized deer in front of you is something that you will never forget. The impact the Burmese python is having on native wildlife cannot be denied. This is a wildlife issue of our time for the Greater Everglades ecosystem,” Bartoszek said.In the past 12 years, the conservancy’s Burmese Python Research and Removal team has removed 770 adult pythons, totaling more than 36,000 pounds.If each of these snakes ate only one deer as big as they could swallow, Jayne estimates that would be a total of more than 13,000 pounds of deer.What gives pythons the ability to eat such large animals?The lower jawbones are not fused at the front, allowing the jaws to stretch wide. Their skin is also elastic, accounting for more than half the circumference of the maximal gape in large pythons, allowing the snakes to consume prey six times larger than similar-sized snakes of some other snake species. “Besides the large absolute size of the deer that was eaten being impressive, our anatomical measurements indicate this deer was very near the size limit on the prey that could be consumed by this snake. Hence, these snakes resemble overachievers by sometimes testing the limits of what their anatomy allows rather than being slackers that eat only ‘snack size’ prey,” Jayne said.The Conservancy of Southwest Florida is an evidence-based organization, and the python tracking team is staying close to the science.“We have been removing pythons and advancing invasive snake science for over a decade. These animals continue to impress us each season and one thing we’ve learned for certain is to not underestimate the Burmese python,” Bartoszek said.The conservancy began its Burmese python research and removal efforts within the bio-region in 2013. As of October 2024, the team has removed over 18 tons of python from an approximately 150-square-mile area in Southwest Florida.The conservancy’s primary objective is to create a database of behavior and habitat use to better understand python activity. This research helps to inform decision-makers, other biologists, and land managers to develop a control strategy for the apex predator.

    According to a new study published in the journal Reptiles and Amphibians, Burmese pythons can consume prey even larger than scientists realized.

    See the story in the video above

    This means that more animals are on the menu across southern Florida, where the non-native, invasive snakes have decimated populations of foxes, bobcats, raccoons and other animals.

    Pythons swallow deer, alligators and other prey whole. What they can eat is limited to and dependent on how big the Burmese python’s mouth can stretch. Researchers call this the snake’s gape.

    Conservancy of Southwest Florida biologists Ian Bartoszek and Ian Easterling recently conducted a study with Dr. Bruce Jayne from the Department of Biological Science at the University of Cincinnati to better understand the ecological impacts of the invasive species.

    The team measured the greatest maximum gape recorded in Burmese pythons to date.

    Professor Jayne said measurements of the longest Burmese python, 19 feet, and two other very large snakes, 15 and 17 feet, captured in Florida show that pythons have a gape bigger than previous mathematical models suggest.

    The largest Burmese python ever captured in Florida weighed a record 215 pounds, stretching 17.7 feet long.

    Previous studies of pythons found the largest gape diameter was 8.7 inches, but the snakes in the current study had a maximal gape of 10.2 inches. These measurements equate to a circumference of 32 inches.

    Conservancy of Southwest Florida

    Three large adult female Burmese pythons researched at the conservancy were examined and used for data and observations of this study, including the longest documented capture on record.

    One python measured for data was found by conservancy biologists while it was ingesting a 77-pound white-tailed deer. The deer was 66.9% of the snake’s mass.

    Burmese Python

    Conservancy of Southwest Florida

    “Watching an invasive apex predator swallow a full-sized deer in front of you is something that you will never forget. The impact the Burmese python is having on native wildlife cannot be denied. This is a wildlife issue of our time for the Greater Everglades ecosystem,” Bartoszek said.

    In the past 12 years, the conservancy’s Burmese Python Research and Removal team has removed 770 adult pythons, totaling more than 36,000 pounds.

    If each of these snakes ate only one deer as big as they could swallow, Jayne estimates that would be a total of more than 13,000 pounds of deer.

    What gives pythons the ability to eat such large animals?

    The lower jawbones are not fused at the front, allowing the jaws to stretch wide. Their skin is also elastic, accounting for more than half the circumference of the maximal gape in large pythons, allowing the snakes to consume prey six times larger than similar-sized snakes of some other snake species.

    “Besides the large absolute size of the deer that was eaten being impressive, our anatomical measurements indicate this deer was very near the size limit on the prey that could be consumed by this snake. Hence, these snakes resemble overachievers by sometimes testing the limits of what their anatomy allows rather than being slackers that eat only ‘snack size’ prey,” Jayne said.

    The Conservancy of Southwest Florida is an evidence-based organization, and the python tracking team is staying close to the science.

    Burmese pythons

    Conservancy of Southwest Florida

    “We have been removing pythons and advancing invasive snake science for over a decade. These animals continue to impress us each season and one thing we’ve learned for certain is to not underestimate the Burmese python,” Bartoszek said.

    The conservancy began its Burmese python research and removal efforts within the bio-region in 2013. As of October 2024, the team has removed over 18 tons of python from an approximately 150-square-mile area in Southwest Florida.

    The conservancy’s primary objective is to create a database of behavior and habitat use to better understand python activity. This research helps to inform decision-makers, other biologists, and land managers to develop a control strategy for the apex predator.

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  • A Neuralink Rival Says Its Eye Implant Restored Vision in Blind People

    A Neuralink Rival Says Its Eye Implant Restored Vision in Blind People

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    One of these, called the Argus II, was approved for commercial use in Europe in 2011 and in the US in 2013. That implant involved larger electrodes that were placed on top of the retina. Its manufacturer, Second Sight, stopped producing the device in 2020 due to financial difficulties. Neuralink and some others, meanwhile, are aiming to bypass the eye completely and stimulate the brain’s visual cortex instead.

    Hodak says the Prima differs from other retinal implants in its ability to provide “form vision,” or the perception of shapes, patterns, and other visual elements of objects. What users see isn’t “normal” vision though. For one, they don’t see in color. Rather, they see a processed image with a yellowish tint.

    The trial enrolled people with geographic atrophy, an advanced form of age-related macular degeneration, or AMD, that causes gradual loss of central vision. People with the condition still have peripheral vision but have blind spots in their central vision, making it difficult to read, recognize faces, or see in low light.

    In AMD, specialized cells called photoreceptors are damaged over time. Located at the back of the retina, photoreceptors convert light into signals that are sent to the brain. “The photoreceptors are lost but the retina is preserved to a large extent. In our approach, the implant takes the place of the photoreceptors,” says Daniel Palanker, a professor of ophthalmology at Stanford University, who invented the Prima implant.

    The Prima implant is a honeycomb pattern of 378 independently controlled pixels that convert infrared light into electrical signals. It measures 2 mm x 2 mm.

    Image Courtesy of Science Corp

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    Emily Mullin

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  • This App Set Out to Fight Pesticides. After VCs Stepped In, Now It Helps Sell Them

    This App Set Out to Fight Pesticides. After VCs Stepped In, Now It Helps Sell Them

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    “Growth, growth, fast growth,” Strey says of what investors were after. “You burn money to grow.” Before its introduction to venture capital, the Plantix team had imagined success as simply making a profitable business. But a modest goal “hasn’t always been that sexy for investors,” who prefer to rapidly build toward a single giant payout, Strey says.

    The team quickly realized that if Plantix was going to survive as a brilliant idea with no clear business model, they would have to give venture capitalists what they wanted: More downloads, more users who could somehow, someday be monetized.

    At that point, Plantix was considering operating in Mali, population 23 million. After learning at an innovation conference that India was home to approximately 150 million smallholders, Strey jumped to shift the company’s focus to the subcontinent. The team quickly established a partnership with a local research group and set up a field office in Hyderabad and began teaching the algorithm to recognize local pests and crops in Indian languages. By the end of January 2018, Plantix had grown to about 300,000 monthly users and raised $4.9 million in one more round of VC funding.

    Moving to India, where food and agriculture is an $800 billion industry, has become an obvious choice for aspiring agritech startups. In recent years, its government has aggressively expanded telecommunications infrastructure, increasing the number of smartphone users to about 450 million people and doubling coverage in rural areas. That meant a farmer walking through an ailing field in Jharkhand could be scrolling Plantix in search of remedies.

    To use the app, farmers provide their crop selection, acreage, and input applications, then upload photos with embedded GPS coordinates. Some growers use the app weekly or even daily, contributing to a deep and detailed real-time image of farming across India. Their use has helped Plantix’s AI grow more accurate while collecting information that could prove invaluable to crop buyers, seed sellers, tool manufacturers, loan lenders, insurance providers, and pesticide sellers.

    During pitches, Strey told me, she saw how investors lit up at just the mention of data. “[The idea] sold good toward the investors, even though we never proved that we could make money out of it.”

    The problem, as many companies have discovered, is that every buyer of data wants some particular slice of the information presented in a specific way. Plantix would need to be reorganized around producing and packaging marketable data products, and the economics never penciled out.

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    Stephen Robert Miller

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  • ‘Absolution’ Excerpt: Read the Beginning of Jeff VanderMeer’s Newest Southern Reach Book

    ‘Absolution’ Excerpt: Read the Beginning of Jeff VanderMeer’s Newest Southern Reach Book

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    But then, too, there was the assurance, the confidence, in the accounts of the biologists as remedy to allay suspicion. Because Sergeant Rocker, too, had then taken to the waters and disappeared, the biologists using their tracking equipment to make sure they could follow the alligators in their new lives.

    The Tyrant kept to herself, while the others remained in close proximity, for a while. None, at least overnight, seemed inclined to leave the area, and by the fourth day, Team Leader 1 put the most junior member of their party on the task of monitoring moments that might include a full day of basking in the same stretch of mud.

    On day six they found Firestorm’s front leg, bobber wire wrapped around it, the whole prominently displayed on a mudbank with deep boot prints suggesting poachers. There was, one biologist wrote, “a bathetic or pathetic quality to the paleness of the leg, enraptured in the evidence of our experiment, lost so far from her home. I wept for an hour, but do not know if this was an appropriate response.”

    (No, Old Jim did not believe it was an appropriate response, even as he himself wept at odd hours, for his own reasons, down in Central’s archives.)

    Battlebee turned up dead and bloated and white, with a chunk ripped out of him postmortem by some creature, possibly Sergeant Rocker, speculation being that stress and the anesthetic had been too hard on him. Postmortem examination revealed stomach contents that included fish, a turtle, mud, and, inexplicably, a broken teacup.

    She had also been pregnant, “a fact that surprised us,” Team Leader 2 wrote, “given her credentials identified her as a male,” amid some general confusion: “To be honest, I cannot now remember when we first took this project on, when we first encountered these subjects. The heat here is abysmal.”

    Sergeant Rocker opted out of the project by shedding his harness in the water near the tent of Team Leader 1, indicating, as she absurdly put it, “A politeness on the part of Sergeant Rocker in keeping with his personality when I knew him best. I felt this loss much more deeply than expected.”

    This sentimentality toward an alligator seen as an obligation just days before weighed on Old Jim, although he could not put a finger on why. Nor did he understand why the alligator experiment registered with the biologists in their reports as a great success, and they would even reference it with a kind of beautiful, all-consuming nostalgia when the mission began to sour. The myth of competence, perhaps. The myth of persistence. The myth of objectivity.

    Perhaps, both he and the biologists would have been wiser to focus on how Sergeant Rocker had turned into an escape artist, for the harness was intact and still latched, with no tears anywhere. So how had the alligator possibly gotten free? Old Jim kept seeing the biologists by a trick of faulty video running away from the release site, only to re-form in their drinking circle.

    He replayed the video so often that it became a disconcerting mess of light and shadow, of pixelated disembodied heads and legs and shapes that leapt out and sharpened, only to become subsumed into the past.

    “All possible measures were taken but nothing could be done.”

    Or had the outcome been exactly as intended?


    Excerpted from Absolution: A Southern Reach Novel by Jeff VanderMeer. Published by MCD, an imprint of Farrar, Straus and Giroux. Copyright © 2024 by VanderMeer Creative, Inc. All rights reserved.

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    Jeff VanderMeer

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  • How Cells Resist the Pressure of the Deep Sea

    How Cells Resist the Pressure of the Deep Sea

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    To study the cell membranes of deep-sea animals, the biochemist Itay Budin (center) joined forces with marine biologists Steve Haddock (right) and Jacob Winnikoff (left).

    Photographs: From left: Tamrynn Clegg; Geoffroy Tobe; John Lee

    “They are looking into an area that, to a large degree, has not been explored,” said Sol Gruner, who researches molecular biophysics at Cornell University; he was consulted for the study but was not a co-author.

    Plasmalogen lipids are also found in the human brain, and their role in deep-sea membranes could help explain aspects of cell signaling. More immediately, the research unveils a new way that life has adapted to the most extreme conditions of the deep ocean.

    Insane in the Membrane

    The cells of all life on Earth are encircled by fatty molecules known as lipids. If you put some lipids in a test tube and add water, they automatically line themselves up back to back: The lipids’ greasy, water-hating tails commingle to form an inner layer, and their water-loving heads arrange together to form the outer portions of a thin membrane. “It’s just like oil and water separating in a dish,” Winnikoff said. “It’s universal to lipids, and it’s what makes them work.”

    For a cell, an outer lipid membrane serves as a physical barrier that, like the external wall of a house, provides structure and keeps a cell’s insides in. But the barrier can’t be too solid: It’s studded with proteins, which need some wiggle room to carry out their various cellular jobs, such as ferrying molecules across the membrane. And sometimes a cell membrane pinches off to release chemicals into the environment and then fuses back together again.

    For a membrane to be healthy and functional, it must therefore be sturdy, fluid, and dynamic at the same time. “The membranes are balancing right on the edge of stability,” Winnikoff said. “Even though it has this really well-defined structure, all the individual molecules that make up the sheets on either side—they’re flowing around each other all the time. It’s actually a liquid crystal.”

    One of the emergent properties of this structure, he said, is that the middle of the membrane is highly sensitive to both temperature and pressure—much more so than other biological molecules such as proteins, DNA or RNA. If you cool down a lipid membrane, for example, the molecules move more slowly, “and then eventually they’ll just lock together,” Winnikoff said, as when you put olive oil in the fridge. “Biologically, that’s generally a bad thing.” Metabolic processes halt; the membrane can even crack and leak its contents.

    To avoid this, many cold-adapted animals have membranes composed of a blend of lipid molecules with slightly different structures to keep the liquid crystal flowing, even at low temperatures. Because high pressure also slows a membrane’s flow, many biologists assumed that deep-sea membranes were built the same way.

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    Yasemin Saplakoglu

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  • Unbelievable facts

    Unbelievable facts

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    A woman gave birth to three children whose DNA didn’t match her own. After being monitored during…

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