Philippa Kaur

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    in Humans

    Don't Miss: Are viruses alive? A timely talk at the Royal Institution

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    Are viruses alive? asks New York Times science columnist Carl Zimmer in this Royal Institution talk. Can viruses and other difficult to pin down microbes help us answer the question: what is life? Streaming live on 26 August at 7pm BST.

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    The Nature Seed by Lucy Jones and Kenneth Greenway is a handy guide to raising adventurous, nature-loving children, full of fires, potions, foraging and make-believe. Discover the awe in a humble cracked pavement or your local park.
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    Watch
    Jamming the Signal is a live conversation at FACT Liverpool on 28 August from 2pm BST that asks whether social media and instant messaging can be used to effect meaningful change in an age of digital unrest. It will also be streamed online. More

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    in Humans

    We need to fully explore the planet to understand our species' origins

    Nino Marcutti/Alamy
    THE tale of human origins continues to throw up surprises. For many years, the generally accepted narrative was that our species emerged on the continent of Africa, before spreading to other continents around 60,000 years ago. It is certainly true that our origins lie primarily in Africa. But in this issue, we explore the crucial role that nearby Arabia played in human evolution.
    Evidence unearthed in Stone Age Arabia points to a much richer story, in which human populations ebbed and flowed in this region over hundreds of thousands  of years as the climate shifted.
    The remarkable discoveries from … More

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    in Humans

    Why adding a road can increase traffic and other modelling delights

    By Simon Ings

    sasilsolutions/Getty Images
    Book

    Atlas of Forecasts: Modeling and mapping desirable futures
    Katy BörnerAdvertisement
    MIT Press

    MY LEAFY, fairly affluent corner of south London has a congestion problem, and to solve it, there is a plan to close certain roads. You can imagine the furore: the trunk of every kerbside tree sports a protest sign. How can shutting off roads improve traffic flows?
    German mathematician Braess answered this question back in 1968, showing that adding a road to a network can actually increase travel times due to a boost in drivers using the same routes and therefore increasing traffic. Now a new book, Atlas of Forecasts: Modeling and mapping desirable futures by Katy Börner, uses it as a fine example of how a mathematical model predicts and can be used to resolve a real-world problem.
    This and more than 1300 other models, maps and forecasts are referenced in Börner’s latest atlas, the third to be derived from Indiana University’s travelling exhibit Places & Spaces: Mapping science.
    Her first, Atlas of Science: Visualizing what we know revealed the power of maps in science, while the second, Atlas of Knowledge: Anyone can map, focused on visualisation. In her latest foray, Börner wants to show how models, maps and forecasts inform decision-making in education, science, technology and policy-making.
    It is a well-structured, heavyweight argument, supported by descriptions of more than 300 applications. Some entries, like Bernard H. Porter’s Map of Physics of 1939, earn their place purely because of their beauty and the insights they offer. Mostly, though, Börner chooses models that were applied in practice and made a positive difference.
    Her range is impressive. We begin at equations, revealing that Newton’s law of universal gravitation has been applied to human migration patterns, and move through the centuries. We tip a wink to Jacob Bernoulli’s 1713 book The Art of Conjecturing –which introduced probability theory – and James Clerk Maxwell’s 1868 paper “On governors”, which was an early nod towards cybernetics. Finally, we arrive at our current era of massive computation and ever-more complex model building.
    It is here that interesting questions start to surface. To forecast the behaviour of complex systems, especially those that contain a human component, many current researchers reach for modelling (ABM) in which discrete autonomous agents interact with each other and with their common (digitally modelled) environment.
    But, warns Börner, “ABMs in general have very few analytical tools by which they can be studied, and often no backward sensitivity analysis can be performed because of the large number of parameters and dynamical rules involved”. In other words, an ABM model offers us an exquisitely detailed forecast, but no clear way of knowing why the model has drawn the conclusions it has – a risky state of affairs, given that its data came from foible-ridden humans.
    Her sumptuous, detailed book tackles issues of error and bias head-on, but she left me tugging at a different problem, represented by those irate protest signs smothering my neighbourhood.
    In over 50 years since Braess’s research was published, reasonably wealthy, mostly well-educated people in comfortable surroundings have remained ignorant of how traffic flows work. So what are the chances that the rest of us, busy and preoccupied as we are, will ever really understand, or trust, the other models that increasingly dictate our civic life?
    Börner argues that modelling data can counteract tribalism, misinformation, magical thinking, authoritarianism and demonisation. I can’t for the life of me see how. What happens when a model reaches such complexity that only an expert can understand it, or when even the expert can’t be sure why the forecast is saying what it is saying?
    We have enough difficulty understanding climate forecasts, let alone explaining them. To apply these technologies to the civic realm begs a host of problems that are nothing to do with the technology, and everything to do with whether anyone will listen.

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    in Humans

    The other cradle of humanity: How Arabia shaped human evolution

    New evidence reveals that Arabia was not a mere stopover for ancestral humans leaving Africa, but a lush homeland where they flourished and evolved

    Humans

    18 August 2021

    By Michael Marshall

    Andrea Ucini
    THE Rub’ al-Khali is both desert and deserted – a landscape of reddish sand dunes that stretches as far as the eye can see. This hyper-arid region in the south-east of the Arabian peninsula is approximately the size of France. Parts of it often go an entire year without rain. Almost nobody lives there; its name means “empty quarter”.
    The rest of Arabia is less environmentally extreme, but still a very tough place to live without air conditioning and other recent technologies. However, the peninsula wasn’t always so parched. A mere 8000 years ago, it was wet enough for there to have been many lakes. The same was true at intervals throughout the past million years, when rivers criss-crossed Arabia, forming green corridors where lush vegetation and wildlife flourished amid the sand dunes. For much of recent geological time, the peninsula was at least partly green.
    Arabia’s verdant past is no mere factoid: it suggests that the region was habitable at times in the distant past. That realisation has prompted archaeologists to start looking for evidence of occupation by humans, their ancestors and their extinct relatives. In just a decade, they have found countless sites where these hominins lived, stretching hundreds of thousands of years into the past. Arabia, it seems, wasn’t a mere stopover for hominins as they moved out of Africa into the wider world. It was somewhere they settled for long stretches of time. Indeed, many researchers now think Arabia should be thought of as part of a “greater Africa”, and that the peninsula played an important role in human evolution and expansion across the world.
    For … More

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    in Space & Astronomy

    Vera Rubin’s work on dark matter led to a paradigm shift in cosmology

    Bright Galaxies, Dark Matter, and BeyondAshley Jean YeagerMIT Press, $24.95

    Vera Rubin’s research forced cosmologists to radically reimagine the cosmos.

    In the 1960s and ’70s, Rubin’s observations of stars whirling around within galaxies revealed the gravitational tug of invisible “dark matter.” Although astronomers had detected hints of this enigmatic substance for decades, Rubin’s data helped finally convince a skeptical scientific community that dark matter exists (SN: 1/10/20).

    “Her work was pivotal to redefining the composition of our cosmos,” Ashley Yeager, Science News’ associate news editor, writes in her new book. Bright Galaxies, Dark Matter, and Beyond follows Rubin’s journey from stargazing child to preeminent astronomer and fierce advocate for women in science.

    That journey, Yeager shows, was rife with obstacles. When Rubin was a young astronomer in the 1950s and ’60s, many observatories were closed to women, and more established scientists often brushed her off. Much of her early work was met with intense skepticism, but that only made Rubin, who died in 2016 at age 88, a more dogged data collector.

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    On graphs plotting the speeds of stars swirling around galaxies, Rubin showed that stars farther from galactic centers orbited just as fast as inner stars. That is, the galaxies’ rotation curves were flat. Such speedy outer stars must be pulled along by the gravitational grip of dark matter.

    Science News staff writer Maria Temming spoke with Yeager about Rubin’s legacy and what, beyond her pioneering research, made Rubin remarkable. The following discussion has been edited for clarity and brevity.

    Temming: What inspired you to tell Rubin’s story?

    Yeager: It all started when I was working at the National Air and Space Museum in Washington, D.C., in 2007. I was walking around the “Explore the Universe” exhibit and noticed there weren’t many women featured. But then there was this picture of a woman with big glasses and cropped hair, and I thought, “Who is this?” It was Vera Rubin.

    My supervisor was a curator of oral histories. He was working on Rubin’s, so I asked him about her. He said, “I have one more oral history interview to do with her. Would you like to come?” So I got to interview her. She was charismatic, kind and curious — not a person who was all about herself, but wanted to know about you. That stuck with me.

    Temming: You spend much of the book describing evidence for dark matter besides Rubin’s research. Why?

    Yeager: I wanted to make sure I didn’t portray Rubin as this lone person who discovered dark matter, because there were a lot of different moving pieces in astronomy and physics that came together in the ’70s and early ’80s for the scientific community to say, “OK, we really have to take dark matter seriously.”

    Temming: What made Rubin’s work a linchpin for confirming dark matter?

    Yeager: She really went after nailing down that flat rotation curve in all types of galaxies. Mainly because she did get a lot of pushback, continually, that said, “Oh, that’s just a special case in that galaxy, or that’s just for those types of galaxies.” She studied hundreds of galaxies to double-check that, yes, in fact, the rotation curves are flat. People saying, “We don’t believe you,” didn’t ever really knock her down. She just came back swinging harder.

    It helped that she did the work in visible wavelengths of light. There had been a lot of radio astronomy data to suggest flat rotation curves, but because radio astronomy was very new, it was really only once you saw it with the eye that the astronomy community was convinced.

    Temming: Do you have a favorite anecdote about Rubin?

    Yeager: The one that comes to mind is how much she loved flowers. She told me about how on drives from Lowell Observatory to Kitt Peak National Observatory in Arizona, she and her colleague Kent Ford would always stop and buy wildflowers. The fact that picking these wildflowers stuck with her, I thought, was just representative of who she was. Her favorite moments weren’t necessarily these big discoveries she’d made, but stopping to pick some flowers and enjoy their beauty.

    Author Ashley Yeager (left) interviewed Vera Rubin (right) in 2007 as part of an oral history project with Smithsonian’s National Air and Space Museum.Smithsonian National Air and Space Museum (NASM 9A16674)

    Temming: Did you learn anything in your research that surprised you?

    Yeager: I didn’t initially grasp how many different types of projects she had. She did a lot with looking for larger-scale structure [in the universe] and looking at the Hubble constant [which describes how fast the universe is expanding] (SN: 4/21/21). She had a very diverse set of questions that she wanted to answer, well into her 70s.

    Temming: I was surprised by her decision to get out of the rat-race of hunting for quasars, when that area of research heated up in the 1960s.

    Yeager: She very much didn’t like to be in pressure situations where she could be wrong. She liked to go and collect so much data that no one could [dispute it]. With quasar research, it was just too fast, and she wanted to be methodical about it.

    Temming: Why is Rubin’s story important to tell now?

    Yeager: Unfortunately for women and minorities in science, it’s still very relevant, in that there are a lot of challenges to pursuing a career in STEM. Her story demonstrates that you have to surround yourself with people who are willing to help you and get away from the people who want to keep you down. Plus her story is also very encouraging: Your curiosity can keep you going and can fuel something way bigger than yourself.

    Temming: How did she advocate for women in astronomy?

    Yeager: She was very outspoken about it. At National Academy of Sciences meetings, the organizers always dreaded her standing up, because she would say, “What are we doing about women in science? We’re not doing enough.” She was constantly pushing for women to be recognized with awards. She kept tabs on the number of women who had earned Ph.D.s and who had gotten staff positions — and their salaries. She was very data-driven. She’d cull that information and use it to advocate for better representation and recognition of women in astronomy.

    Temming: How would you describe Rubin to someone who hasn’t met her?

    Yeager: She was one of the most persistent, gracious and nurturing people that I’ve ever met. You could strip away all that she did in astronomy and she would still be this incredible figure — the way she carried herself, the way she treated people. Just a beautiful human being.

    Buy Bright Galaxies, Dark Matter, and Beyond from Bookshop.org. Science News is a Bookshop.org affiliate and will earn a commission on purchases made from links in this article. More

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    in Humans

    Ancient dog faeces show how our canine friends became omnivores

    By James Urquhart

    Dog food often contains grains – and may have done so for thousands of yearsJaromir Chalabala / Alamy Stock Photo
    Dog diets often contain more starch than those of their carnivorous wolf ancestors, and an analysis of fossilised dog faeces helps explain how the animals made the dietary change. Long before their genomes adapted to their plant-rich chow, their gut microbiome gained a starch-digesting profile.
    Due to their close association with humans, it is thought that dogs’ diets shifted to less meat and more carbohydrates when farming began – an idea that was supported by an archaeological analysis … More

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    in Space & Astronomy

    Measuring a black hole’s mass isn’t easy. A new technique could change that

    An actively feeding black hole surrounds itself with a disk of hot gas and dust that flickers like a campfire. Astronomers have now found that monitoring changes in those flickers can reveal something that is notoriously hard to measure: the behemoth’s heft.

    “It’s a new way to weigh black holes,” says astronomer Colin Burke of the University of Illinois at Urbana-Champaign. What’s more, the method could be used on any astrophysical object with an accretion disk, and may even help find elusive midsize black holes, researchers report in the Aug. 13 Science.

    It’s not easy to measure a black hole’s mass. For one thing, the dark behemoths are notoriously difficult to see. But sometimes black holes reveal themselves when they eat. As gas and dust falls into a black hole, the material organizes into a disk that is heated to white-hot temperatures and can, in some cases, outshine all the stars in the galaxy combined.

    Measuring the black hole’s diameter can reveal its mass using Einstein’s general theory of relativity. But only the globe-spanning Event Horizon Telescope has made this sort of measurement, and for only one black hole so far (SN: 4/22/19). Other black holes have been weighed via observations of their influence on the material around them, but that takes a lot of data and doesn’t work for every supermassive black hole.

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    So, looking for another way, Burke and colleagues turned to accretion disks. Astronomers aren’t sure how black holes’ disks flicker, but it seems like small changes in light combine to brighten or dim the entire disk over a given span of time. Previous research had hinted that the time it takes a disk to fade, brighten and fade again is related to the mass of its central black hole. But those claims were controversial, and didn’t cover the full range of black hole masses, Burke says.

    So he and colleagues assembled observations of 67 actively feeding black holes with known masses. The behemoths spanned sizes from 10,000 to 10 billion solar masses. For the smallest of these black holes, the flickers changed on timescales of hours to weeks. Supermassive black holes with masses between 100 million and 10 billion solar masses flickered more slowly, every few hundred days.

    “That gives us a hint that, okay, if this relation holds for small supermassive black holes and big ones, maybe it’s sort of a universal feature,” Burke says.

    Out of curiosity, the team also looked at white dwarfs, the compact corpses of stars like the sun, which are some of the smallest objects to sport consistent accretion disks. Those white dwarfs followed the same relationship between flicker speed and mass.

    The analyzed black holes didn’t cover the entire possible range of masses. Known black holes that are from about 100 to 100,000 times the mass of the sun are rare. There are several potential candidates, but only one has been confirmed (SN: 9/2/20). In the future, the relationship between disk flickers and black hole mass could tell astronomers exactly what kind of disk flickers to look for to help bring these midsize beasts out of hiding, if they’re there to be found, Burke says.

    Astrophysicist Vivienne Baldassare of Washington State University in Pullman studies black holes in dwarf galaxies, which may preserve some of the properties of ancient black holes that formed in the early universe. One of the biggest challenges in her work is measuring black hole masses. The study’s “super exciting results … will have a large impact for my research, and I expect many others as well,” she says.

    The method offers a simpler way to weigh black holes than any previous technique, Burke says — but not necessarily a faster one. More massive black holes, for example, would need hundreds of days, or possibly years, of observations to reveal their masses.

    Upcoming observatories are already planning to take that kind of data. The Vera C. Rubin Observatory is expected to start observing the entire sky every night beginning in 2022 or 2023 (SN: 1/10/20). Once the telescope has been running long enough, the observations needed to weigh black holes “will fall out for free” from the Rubin Observatory data, Burke says. “We’re already building it. We may as well do this.” More

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    in Humans

    I'm Your Man review: How to fall in love with a robot – maybe

    By Jon O’Brien

    Alma and Tom gradually become closer in this offbeat love storyChristine Fenzl
    Film
    I’m Your Man
    Maria SchraderAdvertisement

    CAN happiness flourish even when it is knowingly built on fabrication? Is perfection conducive to a healthy partnership? Can artificial and emotional intelligence truly coexist? Fresh from her Emmy-winning success with the Netflix miniseries Unorthodox, Maria Schrader leaves such questions hanging in I’m Your Man, her fourth film.
    Adapted from Emma Braslavsky’s short story Ich bin dein Mensch, this German-language tale stars Downton Abbey‘s Dan Stevens as Tom, the ideal life partner. He is a handsome sharp-dresser with blue eyes that could pierce a stone, a penchant for romantic gestures and a willingness to cater to every whim. He is also a humanoid robot.
    Love in the time of algorithms has been explored in the Amazon anthology Soulmates and Netflix’s Osmosis and The One. However, the central coupling here is born out of necessity rather than a search for “the one”.
    Academic Alma (Maren Eggert) has reluctantly agreed to house Tom in a three-week experiment, which will help finance her research. She is completely uninterested in sharing a bed, or even a conversation, with this apparent kindred spirit, created to make her happy. “Leaving me alone should be no problem at all,” she tells Tom, who can’t compute her disdain. “That’s what makes me happiest.”
    I’m Your Man is a curiosity. You could call it a sci-fi rom, yet there is little if any sci-fi or, indeed, rom. The tech behind Tom comes into play just once when he briefly malfunctions, while the film’s Berlin setting is a near-future whose aesthetic is more soft pastels than dark dystopia.
    Despite Tom’s best efforts to ignite a spark using the millions of data strands at his disposal, he is thwarted by a dismissive Alma at every turn. “Ninety-three per cent of German women dream of this,” he remarks, after running a candlelit bath, strewn with rose petals. “Guess which group I belong to,” comes the reply.
    It is only when Tom tones down the programmed cliches and starts responding less, well, robotically that the iciness thaws. He senses the sadness behind Alma’s steely exterior, and his matter-of-fact, yet effective, probing renders their “couples counsellor” (Toni Erdmann‘s Sandra Hüller) obsolete. Before long, Alma surprises herself by defending Tom from a colleague with no sense of personal space.
    If I’m Your Man had emerged from Hollywood, this would be the cue for wedding bells. But European arthouse tends to avoid wrapping things up neatly in a bow. Although she slowly succumbs to Tom’s attributes, both physical and mental, Alma always remains aware that she is being manipulated by his constant recalibration. Happily-ever-after never looks likely.
    Still, the two stars ensure you remain invested in this relationship, wherever it leads. Eggert offsets Alma’s abrasiveness with a quiet vulnerability and compassion, particularly in the scenes with her cranky dad (Wolfgang Hübsch) who has dementia, which hint at her fear of ending up in a lonely state, too.
    Meanwhile, Stevens is charm personified in a performance partly inspired by Cary Grant. His comic timing is exquisite, proving that his scene-stealing turn in last year’s Eurovision movie was no fluke.
    Schrader has served up a new, if resolutely low-key, tragi-comic spin on the digital love story that combines depth, humour and, no matter how mechanical, heart.

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