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    Hundreds of ancient ceremonial sites found in southern Mexico

    Researchers have uncovered 478 ceremonial sites that were probably built by the Olmec and the Maya thousands of years ago

    Humans

    25 October 2021

    By Krista Charles

    A lidar-based image of an ancient ceremonial site in MexicoTakeshi Inomata
    Hundreds of ancient Mesoamerican ceremonial sites built over a period of about 600 years have been uncovered. This comes after the discovery of the first such site – Aguada Fénix – was announced in 2020
    Takeshi Inomata at the University of Arizona and his colleagues used a form of remote sensing called lidar, which uses airborne lasers to form a 3D picture of the surface of the ground. They used this to discover 478 sites in an area covering 84,516 square kilometres in southern Mexico, some of which was covered by dense jungle.
    The sites were made up of rectangular complexes, which the Maya and Olmec probably used for ceremonial gatherings. “People just come and go… sort of like a pilgrimage centre,” says Inomata.Advertisement
    They consisted of a central open plaza, where people might have gathered, with a series of low earthen mounds along the edges where there might have been built structures. And they were probably constructed between 1050 and 400 BC by two ancient civilisations – the Olmec, which was the earliest known civilisation in the region, and the Maya, which may have learned from the Olmec and whose culture collapsed around AD 800.
    “Nobody knew about those rectangular ceremonial sites until we found Aguada Fénix, so all these new findings are a revelation about this early period,” says Inomata. “That really made us rethink about the origin of Mesoamerican civilisation. Many of those complexes were built by people without too much hierarchical organisation.”
    The sites were all relatively flat with a few small pyramids compared with later constructions in the region such as Chichen-Itza that typically contain large pyramids.
    “We don’t know exactly what they might have looked like in life, but one could argue that they were small cities,” says Elizabeth Graham at University College London, who wasn’t involved with the study. “When I first started work in the 70s it was still a time where everyone thought cities developed in the Classic period around 200 AD. Now, steadily the period in which I guess you could say urbanism developed has been pushed back and pushed back.”
    Journal reference: Nature Human Behaviour, DOI: 10.1038/s41562-021-01218-1

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    Astronomers may have spotted the first known exoplanet in another galaxy

    Astronomers may have spotted the first known planet in another galaxy.

    The potential world, called M51-ULS-1b, orbits both a massive star and a dead star in the Whirlpool galaxy, about 28 million light-years from Earth. The object’s existence, if confirmed, suggests that there could be many other extragalactic exoplanets waiting to be discovered, astronomers report in a study to appear in Nature Astronomy.

    “We probably always assumed there would be planets” in other galaxies, says astrophysicist Rosanne Di Stefano of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. “But to actually find something, it’s a beautiful thing. It’s a humbling experience.”

    More than 4,800 planets have been discovered orbiting stars other than the sun, all of them inside the Milky Way. There’s no reason to think that other galaxies don’t also host planets. But the most popular exoplanet hunting techniques are difficult to do with such faraway stars, which blend together too much to observe them one by one.

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    In 2018, Di Stefano and astrophysicist Nia Imara of the University of California, Santa Cruz suggested searching for planets around extragalactic X-ray binaries.

    X-ray binaries usually consist of a massive star and the remains of a second massive star, which has collapsed into a neutron star or a black hole. The dead star steals material from the living star and heats it to such hot temperatures that it emits bright X-rays that stand out from the crowd of other stars.

    That X-ray region can be smaller than a giant planet, meaning if a planet crosses, or transits, in front of such a system from astronomers’ perspective on Earth, it could temporarily block all the X-rays, revealing the planet’s presence.

    Di Stefano and colleagues searched archived data from NASA’s Chandra X-ray telescope for signs of blinking X-ray sources (SN: 7/25/19). The team looked at a total of 2,624 possible transits in three galaxies: M51 (the Whirlpool galaxy), M101 (the Pinwheel galaxy) and M104 (the Sombrero galaxy).

    Only one turned up a clear planetlike signal. On September 20, 2012, an object had blocked all of the X-rays from the X-ray binary M51-ULS-1 for about three hours.

    “We said, ‘Wow. Could this be it?’” Di Stefano says.

    After ruling out gas clouds passing in front of the binary, fluctuations in the X-ray source itself or other explanations for the dip, Di Stefano and colleagues conclude that the object was most likely a Saturn-sized planet orbiting the X-ray binary hundreds of times the distance between Earth and the sun.

    This isn’t a comfortable environment for the planet. “You don’t want to be there,” Di Stefano notes. Despite its distance from the X-ray binary, the planet receives as much energy in X-rays and ultraviolet radiation as a hot Jupiter exoplanet, which orbits its star in just a few days, receives from an ordinary star (SN: 6/5/17).

    “The possibility that the team discovered the transit of an extragalactic planet is quite intriguing and would be a great discovery,” says astrophysicist Ignazio Pillitteri of the Italian National Institute for Astrophysics in Palermo. He would like to see the transit happen again to confirm it.

    Not everyone finds the result convincing. “I find the paper very speculative,” says astrophysicist Matthew Bailes of the Swinburne University of Technology in Melbourne, Australia. If the planet is real, finding it relied on a lot of coincidences: Its orbit needed to be perfectly aligned with the point of view from Earth, and it needed to just happen to be passing in front of the X-ray binary while Chandra was looking.

    Di Stefano counters that the fact that her team saw a signal within such a small number of observations suggests there are lots of extragalactic planets out there. “Maybe we were lucky,” she acknowledges. “But I think it’s very likely that we were not special. We looked and we found something because there was something to find.”

    Di Stefano doesn’t expect to see this particular planet again in her lifetime. It could take decades for it to pass in front of its host stars again. “The real test,” she says, “is finding more planets.” More

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    Becoming Cousteau review: A charming portrait of a conservation icon

    By Elle Hunt

    Jacques-Yves Cousteau was a pioneer of underwater researchThomas J. Abercrombie/National Geographic
    Film
    Becoming Cousteau
    Liz GarbusAdvertisement

    BY HIS own account, the film-maker and ocean explorer Jacques-Yves Cousteau hated it when his work was labelled as “documentary”. “That means a lecture by a guy who knows more than you,” he wrote. “Our films are true adventure films.”
    Becoming Cousteau, a new documentary about Cousteau’s life and legacy, captures that spirit without getting too swept away. The result is a captivating portrait of a complicated man who was as well-known and widely beloved as David Attenborough is today.
    Veteran film-maker Liz Garbus was first approached by National Geographic to make a film about Cousteau’s life in 2015. It was only in 2019, after years of negotiation, that Garbus was granted exclusive access to the Cousteau Society Archives, controlled by Cousteau’s widow Francine. Their children, Pierre-Yves and Diane, have co-producer credits on the film, but in Garbus’s hands, the involvement of those closest to Cousteau serves as an asset, not a liability, helping to paint a picture of a true original.
    Cousteau was a born explorer, with an insatiable drive to see the world and a talent for sharing what he found. He started making films aged 13 and, at 20, entered the French naval academy with a view to becoming a pilot. When his career in aviation was cut short by a car accident, he began swimming on the French Riviera to help heal his broken bones, before becoming fascinated with freediving.
    Soon, he became frustrated with the limits of freediving and, with his naval colleagues, experimented with breathing apparatus that would allow them to spend more time underwater. This led to the invention of the aqualung, which made diving more accessible for both scientists and amateur explorers.
    Archival footage captures the fear and thrill of those early dives, which weren’t so far removed from space exploration at the time in terms of the risks involved.
    In 1947, diver Maurice Fargues died while attempting to set a new depth record with the aqualung. This only focused Cousteau’s mind further. Fargues’s death must not be in vain, Cousteau said.
    “Cousteau abandoned his dream of undersea civilisations to fight for oceans that could support life at all”
    His ultimate goal, at that time, was utopian, “paving the way to a time when human beings will live continuously under the sea“. For Cousteau, diving proposed a route to liberation not just for him, but for all humankind, “to eliminate all ties to the surface”.
    The spirit of this mission was embodied by his research vessel the Calypso, spoken of by its crew as something between a safe haven and a spiritual calling. “This escape would not exist if people were happy on land,” says one sailor. Footage of life onboard from the mid-1950s through the 60s gave ocean exploration a certain glamour. It is no wonder Cousteau’s work inspired a generation of film-makers and seafarers.
    While celebrating Cousteau’s many triumphs, Garbus also engages with his life and work through a contemporary lens, interrogating the cowboyish tactics – such as blast-fishing with dynamite and slaughtering sharks as sailors’ revenge – that were in line with the pioneering spirit of the time, but are antithetical to conservation interests today.
    In 1953, the Calypso – only ever one cheque short of financial ruin – even accepted funding to search for oil in the Persian Gulf. “We just didn’t know any better at the time,” says a crew member.
    Cousteau himself was quick to change course. By the 1970s he had stopped showing his early films, saying “the mentality has changed”, and threw himself into lobbying for protection of the marine ecosystem.
    After documenting two decades of decline, he abandoned his dream of an under-the-sea civilisation to fight to ensure that oceans could support life at all. His series – “no more about dealing with beautiful little fishes, [but] the fate of mankind” – was dropped from US television for being doomsaying.
    Cousteau’s warnings for future generations are even harder to hear now, after 50-plus years of inaction. But his story inspires hope about what can be achieved by one person with a vision.

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    We now know Vikings were in the Americas exactly 1000 years ago

    By Michael Marshall

    A panoramic view of L’Anse aux Meadows in Newfoundland, CanadaBob Hilscher/Getty Images
    Before Christopher Columbus, Vikings were the first Europeans to reach the Americas. We now know to the year when they were there. Norse people were chopping down trees in Newfoundland in the year AD 1021, so they must have crossed the Atlantic Ocean by then.
    “Exactly a millennium ago, human beings for the first time in history had got across [the Atlantic],” says Michael Dee at the University of Groningen in the Netherlands.
    Evidence for a Norse presence in North … More

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    Why the ancestors of dogs were our colleagues not friends

    By Simon Ings

    WHEN Spanish and other European forces entered South America in the 15th century, they used dogs as weapons to massacre the indigenous human population. Sometimes, their mastiffs, enormous brutes trained to chase and kill, even fed on the bodies of their victims.
    This didn’t quell the affection in South America for dogs, though. Ferocious as they were, these beasts were also novel, loyal and intelligent and a trade in them spread across the continent.
    What is it about dogs that makes them so irresistible?
    In Our Oldest Companions, anthropologist Pat Shipman traces the ancient drivers that led to our species’ special relationship with dogs. It is an epic, and occasionally unnerving, tale of love and loyalty, hunting and killing, gleaned from a huge amount of archaeological and palaeogenetic research.
    In Shipman’s view, there was nothing inevitable about the development of the grey wolf – a fierce, meat-eating competitor – into the playful friends that we know today. As Shipman puts it: “Who would select such a ferocious and formidable predator as a wolf for an ally and companion?”
    To find the answer, says Shipman, forget the old tale in which someone captures a baby animal, tames it, raises it, selects a mate for it and brings up the friendliest babies.
    Instead, she argues, it was the particular ecology of Europe about 50,000 years ago that drove grey wolves and human interlopers from Mesopotamia to develop a symbiotic relationship that set the stage for our future friendship.
    “Who would select such a ferocious and formidable predator as a wolf for an ally and companion?”
    Working together allowed humans to tap into the wolves’ superior speed and senses, and to gain their protection against other large predators including lions. The wolves, in turn, benefited from a human’s ability to kill prey at a distance with spears or arrows.
    It was a partnership that allowed them to net enough food to share, and to outcompete the indigenous Neanderthals who didn’t have a team of super-fast predators to help them.
    This idea was explored in Shipman’s 2015 book The Invaders In Our Oldest Companions, she develops her argument by exploring parts of the world where dogs and humans didn’t evolve similar behaviours.
    Australia provides Shipman with her most striking example. When Homo sapiens arrived in Australia, around 65,000 years ago they came without domesticated dogs, because, at the time, there was no such thing.
    When the ancestors of today’s dingoes were brought to Australia about 3000 years ago, their charisma earned them a central place in Indigenous Australian folklore, but there was no incentive for the two species to live and work together. Australia was less densely populated by large animals than Europe and there were only two large mammalian predators, the Tasmanian tiger and the marsupial lion, to deal with. As a result, says Shipman, while dingoes are eminently tameable, they have never been domesticated.
    With the story of humans and dogs in Asia, Shipman goes against the grain. While some researchers argue that the bond between wolf and man was first established here, Shipman is having none of it. She points to a crucial piece of non-evidence: if dogs first arose in Asia, then where are the ancient dog burials?
    Cute, but there was never a good enough reason to team up with dingoesJulie Fletcher/Getty Images
    “Deliberate burial,” writes Shipman, “is just about the gold standard in terms of evidence that an animal was domesticated.” There are no such ancient graves in Asia, she points out. It is on the right bank of the Rhine in what is now Germany, that the earliest remains of a clearly domesticated dog were discovered. Known as the Bonn-Oberkassel dog, and dating from 14,200 years ago, it was found in 1914, tucked between two human skeletons, the grave decorated with works of art made of bones and antlers.
    From there, domesticated dogs remained firmly in our hearts and homes There are now more than 300 subspecies, although overbreeding has left hardly any that are capable of carrying out their intended functions of hunting, guarding or herding.
    Shipman passes no comment on this, but I can’t help but think it is a sad end to a story that began among mammoths and lions.

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    Why psychologists can't decide if moral disgust is even a thing

    By Ana Aznar

    Michelle D’urbano
    WE SHOULD really care about disgust. Not only does it protect us from coming into contact with possibly dangerous substances, such as rotting meat, but it is also central to understanding our moral compasses.
    Yet, up until around 20 years ago, it was essentially absent from psychological research. Today, it is still shrouded in confusion. All other basic emotions, such as sadness and happiness, have a clear definition, but when it comes to disgust, psychologists are divided over whether it should actually be split into physical disgust and moral disgust, or whether it is only physical disgust that exists.
    Physical disgust is that feeling caused by things such as vomit or faeces. This varies between people, but it helps protect us from touching or ingesting potentially dangerous substances that could put our survival at risk.Advertisement
    Moral disgust, on the other hand, is normally described as the feeling you get when hearing someone has broken social norms or moral codes. Seeing a person steal or hearing about someone having an affair, for example, might be enough to set off this emotion in you.
    Some psychologists argue that physical and moral disgust are two sides of the same coin. Others insist that, although the word “disgust” is used in both situations, when moral norms are broken, what people are actually experiencing is anger.
    Disgust and anger are both negative emotions that have been linked with morality, but whereas disgust motivates us to avoid things, anger pushes us to confront whatever it is that is making us angry.
    In my latest research, I have been examining the schism in psychology on disgust further using parent-child conversations. These are a valuable tool for developmental psychology as parents use them to teach their children about emotions, values and moral issues. They may also be particularly relevant to our understanding of disgust because children only begin to understand it when they are 3 to 4 years old, around a year later than the other basic emotions. This suggests there is a social component to disgust and that children’s understanding of it may be partly learned from their parents.
    In the research, my colleagues and I asked 68 English-speaking mothers and their 4, 6 or 8-year-old children to discuss a series of short stories. In each of them, the main character performed either a physical transgression, such as wearing dirty clothes or sitting on a dirty chair, or a moral one, such as copying someone’s homework or jumping a queue. We then asked the mothers and children to talk about the emotion that they would feel after each transgression.
    We found that both were more likely to say that they were disgusted by physical transgressions than they were angry. In contrast, when discussing moral transgressions, they were more likely to say that they made them angry rather than disgusted. Mothers and children also often said that these actions were wrong.
    What this seems to suggest is that mothers and children are more likely to link disgust with physical transgressions and anger with moral ones.
    Does this mean there is no such thing as moral disgust? We think it certainly points that way.
    Our research won’t settle the controversy around the existence of moral disgust on its own. However, the more we learn about it, the closer we get to understanding how we develop a sense of morality.

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    Ancient faeces show Iron Age miners ate blue cheese and drank beer

    By Carissa Wong

    Ancient faeces found in salt mines in Hallstatt, AustriaAnwora/NHMW
    Fungi found in faeces from Iron Age people who worked in salt mines in what is now Austria suggest that people were eating blue cheese and beer at least 2700 years ago.
    There is earlier evidence for ancient cheese, found in Early Bronze Age tombs in Western China from nearly 4000 years ago, but these fossilised faeces provide the earliest evidence that “people produced cheese with even a flavour that is found in blue cheese”, says Frank Maixner at Eurac Research in … More

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    A Jupiter-like planet orbiting a white dwarf hints at our solar system’s future

    A glimpse of our solar system’s future has appeared thousands of light-years away in the constellation Sagittarius. There a giant planet like Jupiter orbits a white dwarf, a dim, dense star that once resembled the sun.

    In 2010, that star passed in front of a much more distant star. Like a magnifying glass, the white dwarf’s gravity bent the more distant star’s light rays so that they converged on Earth and made the distant star look hundreds of times brighter. A giant planet orbiting the white dwarf star also “microlensed” the distant star’s light, revealing the planet’s presence.

    In 2015, 2016 and again in 2018 astrophysicist Joshua Blackman of the University of Tasmania in Hobart, Australia and colleagues pointed the Keck II telescope in Hawaii at the far-off system, which lies some 5,000 to 8,000 light-years from Earth. The team was in search of the giant planet’s star, but saw, well, nothing.

    “We expected that we’d see a star similar to the sun,” Blackman says. “And so we spent quite a few years trying to figure out why on Earth we didn’t see the star which we expected to see.”

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    After failing to detect any light from the spot where the planet’s star should be, Blackman’s team concluded that the object can’t be a typical star like the sun — also known as a main sequence star, which generates energy by converting hydrogen into helium at its center. Instead, the star must be something much fainter. The microlensing data indicate that the star is roughly half as massive as the sun, so the object isn’t massive enough to be a neutron star or black hole. But a white dwarf star fits the bill perfectly, the researchers report online October 13 in Nature.

    “They’ve carefully ruled out the other possible lens stars — neutron stars and black holes and main sequence stars and whatnot,” says Ben Zuckerman, an astronomer at UCLA, who was not involved with the work. He notes that only a handful of planets have ever been found orbiting white dwarfs.

    The new planet is the first ever discovered that is orbiting a white dwarf and resembles Jupiter in both its mass and its distance from its star. Blackman’s team estimates that the planet is one to two times as massive as Jupiter and probably lies 2.5 to six times farther from the white dwarf star than Earth does from the sun. For comparison, Jupiter is 5.2 times farther out from the sun than Earth is. The white dwarf is somewhat larger than Earth, which means the planet is much bigger than its host star.

    The white dwarf formed after a sunlike star expanded and became a red giant star. Then the red giant ejected its outer layers, exposing its hot core. That former core is the white dwarf star.

    Our sun will turn into a white dwarf about 7.8 billion years from now, so the new discovery is “a snapshot into the future of our solar system,” Blackman says. As the sun becomes a red giant, it will engulf and destroy its innermost planet, Mercury, and perhaps Venus too. But Mars, Jupiter and more distant planets should survive.

    And Earth? No one yet knows what will happen to it. More