Philippa Kaur

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    in Humans

    Family tree of extinct apes reveals our early evolutionary history

    A new family tree of apes that lived in the Miocene between 23 and 5.3 million years ago reveals which are our close relatives and which are only distant cousins

    Humans

    16 March 2022

    By Michael Marshall
    Dryopithecus, an extinct ape from the MioceneJOHN SIBBICK/SCIENCE PHOTO LIBRARY
    A huge study of fossil apes clarifies which extinct species are most closely related to humans. But it can’t resolve one of the most controversial questions in human evolution: whether the last common ancestor we shared with living African apes like chimpanzees lived in Africa or Eurasia.
    Primatologist Kelsey Pugh at the American Museum of Natural History in New York looked at apes that lived during the Miocene epoch, between 23 and 5.3 million years ago. She focused on those from the middle … More

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    in Humans

    A new reference human genome could reflect our species’ true diversity

    The current reference human genome is based on a handful of people but the new Pangenome project will incorporate DNA from hundreds of people all around the world

    Humans

    16 March 2022

    By Michael Marshall
    DNA sequence dataShutterstock / Gio.tto
    The human genome is being sequenced again – but better. A new project to read DNA from a large number of people has launched, with the aim of sequencing the “pangenome”, a version of the genome that reflects the full genetic diversity of our species.
    The human genome, the set of DNA that every person carries in their cells, was first read or “sequenced” between 1990 and 2001. However, this first genome was incomplete because many chunks couldn’t be reconstructed. Geneticists have improved it since, with the last major … More

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    in Humans

    Non-pilots think they can land a plane after watching a YouTube video

    A psychological study shows people can be over-confident in their ability to perform tasks for which they have no formal training

    Humans

    16 March 2022

    By Christa Lesté-Lasserre
    Pilot working through a simulation a simulation exerciseChris Urso/Tampa Bay Times/ZUMA Wire/Alamy
    People can be so confident they can teach themselves skills they actually lack – including the ability to land a commercial jet – that they could actually put themselves and other people in serious danger.
    “People think, ‘Well, if it really mattered, like in an emergency, I could land the plane’,” says Maryanne Garry at the University of Waikato, in New Zealand. “But … that requires skills that most people just don’t have.”
    Garry and her colleagues enlisted 780 volunteers for their psychological study. Half of the study participants were asked to watch an approximately 4-minute-long silent YouTube video showing two commercial pilots landing a plane in a mountainous area.Advertisement
    The scientists then gave each participant a hypothetical scenario:
    Imagine you are on a small commuter plane. Due to an emergency, the pilot is incapacitated and you are the only person left to land the plane.
    They then asked the participants how confident they would feel – on a percentage scale – about responding to the situation.
    They found that people who had watched the video were up to 30 per cent more confident in their ability to land a plane without dying, compared to the confidence ratings of people who had not watched the video. But even people who had not watched the video gave themselves an average confidence score of 29 per cent for their ability to land the plane without dying, says Garry.
    Some participants who watched the video were asked prior to doing so how confident they were they could land the plane as well as any trained pilot. After watching the video, their self-confidence rose: they were up to 38 per cent more confident that they could perform as well as any trained pilot. In general, men were significantly more confident in their abilities than women were, she adds.

    The results were particularly surprising, the researchers say, given that the respondents in general were convinced that landing a plane requires a great deal of expertise. They ranked the required skill level for landing a plane at an average of 4.4 out of 5, says Garry. Trained pilots learn to land planes after hundreds of hours of training and education in physics, engineering, and meteorology, she adds.
    Garry says the findings suggest that people “tend to inflate their confidence about certain things” as a result of what she calls a “rapid illusion”, meaning they see images that make them believe they are capable of feats for which they actually have no skill. She adds that the findings suggest this applies to a “disturbing proportion of ordinary people”.
    While overconfidence has its benefits – for example, giving people a boost that helps them take on life’s challenges – it can also be detrimental when it puts people’s lives in danger, says Kayla Jordan, also at the University of Waikato.
    “It’s pretty surprising that people become more confident they could carry out this highly-specialised feat – while at the same time telling us they know that landing a plane requires a great deal of expertise,” says Jordan.
    Journal reference: Royal Society Open Science, DOI: 10.1098/rsos.211977

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    in Space & Astronomy

    Some of the sun’s iconic coronal loops may be illusions

    Coronal loops, well-defined hot strands of plasma that arch out into the sun’s atmosphere, are iconic to the sun’s imagery. But many of the supposed coronal loops we see might not be there at all.    

    Some coronal loops might be an illusion created by “wrinkles” of greater density in a curtain of plasma dubbed the coronal veil, researchers propose March 2 in Astrophysical Journal. If true, the finding, sparked by unexpected plasma structures seen in computer simulations of the sun’s atmosphere, may change how scientists go about measuring some properties of our star.

    “It’s kind of inspiring to see these detailed structures,” says Markus Aschwanden, an astrophysicist at Lockheed Martin’s Solar & Astrophysics Lab in Palo Alto, Calif., who was not involved in the study. “They are so different than what we anticipated.”

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    Scientists have begun to develop a better understanding of the sun’s complex atmosphere, or corona, only in the last few years (SN: 12/19/17). Coronal loops have been used to measure many properties of the corona, including temperature and density, and they may be key to figuring out why the sun’s atmosphere is so much hotter than its surface (SN: 8/20/17). But astronomers have long wondered just how the loops appear to be so orderly when they originate in the sun’s turbulent surface (SN: 8/17/17).     

    So solar physicist Anna Malanushenko and her colleagues attempted to isolate individual coronal loops in 3-D computer simulations originally developed to simulate the life cycle of a solar flare. The team expected to see neatly oriented strands of plasma, because coronal loops appear to align themselves to the sun’s magnetic field, like metal shavings around a bar magnet.

    Instead, the plasma appeared as a curtainlike structure winding out from the sun’s surface that folded in on itself like a wrinkled sheet. In the simulation, many of the supposed coronal loops turned out to not be real objects. While there were structures along the magnetic fields, they were neither thin nor compact as expected. They more closely resembled clouds of smoke. As the team changed the point of view from which they looked at these wrinkles in the veil in the simulation, their shape and orientation changed. And from certain viewing angles, the wrinkles resembled coronal loops.

    The observations were mind-blowing, says Malanushenko, of the National Center for Atmospheric Research in Boulder, Colo. “The traditional thought was that if we see this arching coronal loop that there is a garden hose–like strand of plasma.” The structure in the simulation was much more complex and displayed complicated boundaries and a raggedy structure.

    Still, not all coronal loops are necessarily illusions within a coronal veil. “We don’t know which ones are real and which ones are not,” Malanushenko says. “And we absolutely need to be able to tell to study the solar atmosphere.”

    It’s also not clear how the purported coronal veil might impact previous analyses of the solar atmosphere. “On one hand, this is depressing,” Malanushenko says of the way the new findings cast doubt on previous understandings. On the other hand, she finds the uncertainty exciting. Astronomers will need to develop a way to observe the veil and confirm its existence. “Whenever we develop new methods, we open the door for new knowledge.” More

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    in Space & Astronomy

    Earth’s purported ‘nearest black hole’ isn’t a black hole

    The nearest black hole to Earth isn’t a black hole at all. Instead, what scientists thought was a stellar triplet — two stars and a black hole — is actually a pair of stars caught in a unique stage of evolution.

    In May 2020, a team of astronomers reported that the star system HR 6819 was probably made up of a bright, massive star locked in a tight, 40-day orbit with a nonfeeding, invisible black hole plus a second star orbiting farther away. At about 1,000 light-years from Earth, that would make this black hole the nearest to us (SN: 5/6/20). But over the following months, other teams analyzed the same data and came to a different conclusion: The system hosts only two stars and no black hole.

    Now, the original team and one of the follow-up teams have joined forces and looked at HR 6819 with more powerful telescopes that collect a different type of data. The new data can make out finer details on the sky, allowing the astronomers to definitively see how many objects are in the system and what type of objects they are, the teams report in the March Astronomy & Astrophysics.

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    “Ultimately, it was the binary system that best explains everything,” says astronomer Abigail Frost of KU Leuven in Belgium.

    Previous observations of HR 6819 showed it as a unit, so astronomers couldn’t differentiate the objects in the system nor their masses. To nail down HR 6819’s true nature, Frost and colleagues turned to the Very Large Telescope Array, a network of four interconnected telescopes in Chile that can essentially see the separate stars.

    “It allowed us to disentangle that original signal definitively, which is really important to determine how many stars were in it, and whether one of them was a black hole,” Frost says.

    The scientists think one of the stars is a massive bright blue star that has been siphoning material from its companion star’s bloated atmosphere. That companion star now has little gaseous atmosphere left. “It’s already gone through its main life, but because the outside has been stripped off, and you only see the exposed core, it has similar temperature and luminosity and radius to a young star,” says Kareem El-Badry, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. El-Badry was not involved in the new study, but he suggested in 2021 that HR 6819 is a binary system.

    This siphoned star’s core color and brightness could fool astronomers looking at the older data into thinking it was a young star with 10 times as much mass. It originally appeared as though this star was orbiting something massive but invisible — a black hole.

    Once the researchers unraveled the system’s details, they realized this system is a unique one, showing astronomers a phase not seen before among systems with massive stars. “It is a missing link in binary star evolution,” says astrophysicist Maxwell Moe of the University of Arizona in Tucson, who was also not part of the new study.

    Astronomers for years have seen binary systems where one star is actively pulling gas off the other, and they’ve seen systems where the donor star is just a naked stellar core. But in HR 6819, the donor star has stopped giving mass to the other. “It still has a little bit of envelope left but is quickly contracting, evolving to become a remnant core,” Moe says.

    Frost and her colleagues are using the Very Large Telescope Array to monitor HR 6819 over a year to track precisely how the stars are moving. “We want to really understand how the individual stars in the system are ticking,” she says. The team will then use that information in computer simulations of binary star evolution. “[It’s] exciting to now have a system that we can use as kind of a cornerstone to investigate this in more detail,” Frost says.

    Even though HR 6819 doesn’t have the nearest black hole to Earth, it appears to have something more useful to astronomers. More

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    in Humans

    Time to take a long, hard look at humanity's future in the cosmos

    Shutterstock/Romolo Tavani
    SOMETIMES it pays to take the long view. Look at the past half-century of cosmology, as UK Astronomer Royal Martin Rees does in our interview, and it is plain how far we have come.
    The story of the universe’s origin in a big bang – an idea not especially favoured when Rees started as a researcher in the 1960s – is now as close to an established fact as science permits. We have also elucidated the properties and phenomena of an unimaginably vast cosmos with ever more acuity. It is a privilege to live in an age when, for the first time, we have a convincing story of most of the grand sweep of cosmic evolution.
    “If so many planets are out there, how come intelligent life hasn’t come our way?”Advertisement
    These are truly thrilling developments, albeit ones that have, in the nature of science, thrown up more holes in our understanding – holes that instruments such as the recently launched James Webb Space Telescope are designed to plug.
    Yet this progress also gives reason for introspection. Many researchers like Rees find themselves drawn to questions of humanity’s future. The discovery of thousands of exoplanets circling other stars, and the realisation that even icy moons in the outer solar system might harbour warm and wet environments, boosts the belief that if life exists on one tiny blue dot, it might exist elsewhere, too.
    So why hasn’t intelligent life elsewhere made itself known to us? Perhaps because hubristic missteps give technological civilisations a limited lifespan – and perhaps also because, as we have learned, space is an unforgiving environment. It is a half-century now since the last person walked on the moon and, as Rees warns, while billionaires such as Elon Musk battle it out to return there, it is folly to think “space tourism” will ever be the norm for our species. Any vestiges of humanity that leave our solar system will probably be very different to us, and most likely the progeny of the pioneers who establish a future beyond Earth, on Mars for example.
    For the rest of us, our planet is all there is. The problems we face, not least the tragedy currently unfolding in Ukraine, are a reminder that progress can just as easily be undone. All the more reason to apply our common humanity to solving the problems of the here and now. More

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    in Humans

    Make mistakes on purpose – it can dramatically boost your performance

    “Deliberate erring” offers a surprising but effective way to enhance your memory and improve how you perform in many unexpected areas of life, says David Robson

    Humans

    | Columnist

    9 March 2022

    By David Robson
    Catherine Falls Commercial/Getty Images
    A man of genius makes no mistakes,” James Joyce wrote 100 years ago. “His errors are volitional and portals to discovery.”
    Most people with good sense would accept that we can and should learn from accidental failures. It would be impossible to progress in anything, after all, without taking the odd misstep, and by understanding how we tripped up, we can avoid stumbling in the future.
    Few would advocate making intentional mistakes, however. Yet a pair of fascinating new studies have shown that this may be the best way to learn new information. Consciously blundering, even when you know … More

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    in Humans

    The Parrot in the Mirror review: Why humans evolved to be like birds

    From our long lives to our social skills and even language, zoologist Antone Martinho-Truswell argues that we are more like birds than we think

    Humans

    9 March 2022

    By Simon Ings

    EVOLUTION has created a living world of jaw-dropping diversity. It has also generated what seem like astonishing coincidences. The pangolins of Africa and armadillos of South America, for instance, look like close cousins. In fact, each is more closely related to humans than to each other. Their similarity arises because they independently evolved near-identical strategies to cope with the same kind of environmental challenges.
    This is just one example of what is known as convergent evolution, but there are many others, and not all of them are so easy to spot. Take humans and birds: few readers will be immediately won over by Sydney-based zoologist Antone Martinho-Truswell’s claims that we are “like a strangely featherless bird”, and that we have more in common with birds than with our mammalian cousins.
    By the time I finished The Parrot in the Mirror, though, I found that idea both compelling and reasonable. Martinho-Truswell explores the traits shared by humans and birds, from our unusual longevity to our advanced social skills, from our parenting styles to our intelligence and even the use of language. These, he argues, are all examples of convergent evolution.
    Briefly, his argument goes like this: once birds could fly, they could elude almost all predators. Since they were now less likely to be eaten in any given year, they could live longer and produce more offspring. With longevity came the opportunity and the need to develop increased intelligence. It is an advantage for long-living animals to be smart because it helps them to survive long enough to raise their young to adulthood. What’s more, because longer development requires a bigger egg and a bigger yolk sac, and because an egg can only get so big if its mother is to fly, most birds hatch out very immature, helpless young. Chicks require enormous amounts of care, often provided by pair-bonded parents, and sometimes supplemented by a larger community. This favours the evolution of complex social behaviour and communication.
    Martinho-Truswell argues that the human evolutionary story is a warped mirror image of this. Our story begins, not with flight, but with communal behaviour among primates, which promoted the evolution of intelligence and social behaviour. This reduced the likelihood of predation, and longevity followed, boosting intelligence to the point where big-brained human young have to be born immature and helpless so as not to endanger their mothers’ lives during childbirth.
    So, the argument goes, humans and birds evolved measurable intelligence in response to similar challenges. But how do we compare our abilities?
    In this regard, Martinho-Truswell does well to strike a balance between precision and imagination. On the one hand, a duckling’s ability to identify its mother shortly after the moment of its birth puts it well ahead of chimpanzees, parrots, pigeons, crows and even human children. But this one hardwired ability doesn’t necessarily make the duckling more intelligent.
    “Humans and birds evolved intelligence in response to similar challenges. But how do we compare abilities?”
    On the other hand, it would be a dull observer indeed that didn’t see quite staggering evidence of advanced cognition in Irene Pepperberg’s 30-year study of language use in Alex, an African grey parrot. The bird not only answered questions, he asked them, too. And he got annoyed if people gave him silly answers.
    Containing the complexities of convergent evolution in a straightforward narrative isn’t easy. Evolutionary causes and effects don’t follow each other in neat, storybook fashion, and there is always the temptation, reading this book, to take Martinho-Truswell’s acts of narrative shorthand at face value and suppose that humans, 50 million years behind parrots in the evolution of intelligence, somehow became more human by actually mimicking their distant avian cousins.
    Clearly that isn’t the case. But perhaps it is better to be slightly misled by a gripping story than to be bludgeoned by a dull one. Martinho-Truswell has written a superb introduction to a surprisingly complex field of study. Having read it, you won’t look at yourself in the mirror in quite the same way.

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