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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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    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

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    The fastest-spinning white dwarf ever seen rotates once every 25 seconds

    The sun turns once a month and the Earth once a day, but a white dwarf star 2,000 light-years away spins every 25 seconds, beating the old champ by five seconds. That makes it the fastest-spinning star of any sort ever seen — unless you consider such exotic objects as neutron stars and black holes, some of which spin even faster, to be stars (SN: 3/13/07).  

    About as small as Earth but roughly as massive as the sun, a white dwarf is extremely dense. The star’s surface gravity is so great that if you dropped a pebble from a height of a few feet, it would smash into the surface at thousands of miles per hour. The typical white dwarf takes hours or days to spin.

    The fast-spinning white dwarf, named LAMOST J0240+1952 and located in the constellation Aries, got in a whirl because of its ongoing affair with a red dwarf star that revolves around it. Just as falling water makes a waterwheel turn, so gas falling from the red companion star made the white dwarf twirl.

    The discovery occurred the night of August 7, when astronomer Ingrid Pelisoli of the University of Warwick in Coventry, England, and her colleagues detected a periodic blip of light from the dim duo. The blip repeated every 24.93 seconds, revealing the white dwarf star’s record-breaking rotation period, the researchers report August 26 at arXiv.org.

    The star’s only known rival is an even faster-spinning object in orbit with the blue star HD 49798. But that rapid rotator’s nature is unclear, with some recent studies saying it is likely a neutron star, not a white dwarf. More

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    Ancient seeds reveal we began using tobacco at least 12,300 years ago

    By Carissa Wong

    Modern cultivated tobacco (Nicotiana tabacum) seed vesselsblickwinkel / Alamy
    Seeds discovered at an ancient campsite in Nevada indicate people have been using tobacco for at least 12,300 years, which is far longer than previously thought.
    Tobacco plants are native to North America, and humans are thought to have reached the continent around 20,000 to 16,000 years ago. “This suggests that people learned the intoxicant properties of tobacco relatively early in their time here rather than only with domestication and agriculture thousands of years later,” says Daron Duke at the … More

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    Football teams lost home advantage in lockdowns but it is coming back

    By Luke Taylor

    The roar of the home crowd really does have an impactClive Rose/Getty Images
    It is a long-held belief that football teams playing in their home stadium get a boost from their fans. However, quantifying this effect on match results was difficult until the pandemic created an unprecedented natural experiment when most of the 2020/21 season was played behind closed doors.
    Statistics shared with New Scientist by London-based sports intelligence firm Twenty First Group show that home teams in Europe’s five major men’s football leagues lost a significant home advantage when their games … More

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    China’s lunar rock samples show lava flowed on the moon 2 billion years ago

    Lava oozed across the moon’s surface just 2 billion years ago, bits of lunar rocks retrieved by China’s Chang’e-5 mission reveal.

    A chemical analysis of the volcanic rocks confirms that the moon remained volcanically active far longer that its size would suggest possible, researchers report online October 7 in Science.

    Chang’e-5 is the first mission to retrieve lunar rocks and return them to Earth in over 40 years (SN: 12/1/20). An international group of researchers found that the rocks formed 2 billion years ago, around when multicellular life first evolved on Earth. That makes them the youngest moon rocks ever collected, says study coauthor Carolyn Crow, a planetary scientist at the University of Colorado Boulder.  

    The moon formed roughly 4.5 billion years ago. Lunar rocks from the Apollo and Soviet missions of the late 1960s and 70s revealed that volcanism on the moon was commonplace for the first billion or so years of its existence, with flows lasting for millions, if not hundreds of millions, of years.

    Samples of bits of lunar rocks, such as this, are helping scientists study the volcanic evolution of the moon.Beijing SHRIMP Center/Institute of Geology/CAGS

    Given its size, scientist thought that the moon started cooling off around 3 billion years ago, eventually becoming the quiet, inactive neighbor it is today. Yet a dearth of craters in some regions left scientists scratching their heads. Parts of celestial bodies devoid of volcanism accumulate more and more craters over time, in part because there aren’t lava flows depositing new material that hardens into smooth stretches. The moon’s smoother spots seemed to suggest that volcanism had persisted past the moon’s early history.  

    “Young volcanism on a small body like the moon is challenging to explain, because usually small bodies cool fast,” says Juliane Gross, a planetary scientist at Rutgers University in Piscataway, N.J., not involved in the study.

    Scientist had suggested that radioactive elements might offer an explanation for later volcanism. Radioactive decay generates a lot of heat, which is why nuclear reactors are kept in water. Enough radioactive materials in the moon’s mantle, the layer just below the visible crust, would have provided a heat source that could explain younger lava flows.

    To test this theory, the Chang’e-5 lander gathered chunks of basalt — a type of rock that forms from volcanic activity — from a previously unexplored part of the moon thought to be younger than 3 billion years old. The team determined that the rocks formed from lava flows 2 billion years ago, but chemical analysis did not yield the concentration of radioactive elements one would expect if radioactive decay were to explain the volcanism.

    The Chang’e-5 lunar lander extracts samples of the moon that were returned to Earth. The lunar material is the first brought back to Earth in more than 40 years.Chinese National Space Agency’s Lunar Exploration and Space Engineering Center

    This finding is compelling scientists to consider what other forces could have maintained volcanic activity on the moon.

    One theory, says study coauthor Alexander Nemchin, a planetary scientist at the Beijing SHRIMP Center and Curtin University in Bentley, Australia, is that gravitational forces from the Earth could have liquefied the lunar interior, keeping lunar magma flowing for another billion or so years past when it should have stopped.

    “The moon was a lot closer 2 billion years ago,” Nemchin explains. As the moon slowly inched away from the Earth — a slow escape still at work today — these forces would have become less and less powerful until volcanism eventually petered out.

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    Impacts from asteroids and comets also could have kept the moon’s volcanic juices flowing, but “at this point, any guess is a good guess,” says Jessica Barnes, a planetary scientist at the University of Arizona in Tucson not involved in the study.

    “This is a good example of why we need to get to know our closest neighbor,” Barnes says. “A lot people think we already know what’s going on with the moon, but it’s actually quite mysterious.” More

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    Eating to Extinction review: Are our bland diets bad for the world?

    By Gege Li

    The foraging of Hadza honey in Tanzania is under threat due to increasing demand for landKatiekk2/Getty Images
    Book
    Eating to Extinction
    Dan SaladinoAdvertisement

    OUR diets are more homogenous than at any other point in human history, says food journalist Dan Saladino. Particularly in the West, a revolution in farming methods since the second world war has led us to a point where much of what we eat comes from just a few established varieties of crops and animals, controlled by a handful of companies.
    This has undoubtedly had many benefits for humanity, making food supplies more predictable, cheaper and more accessible, and helping to curb malnutrition. Yet in his new book, Eating to Extinction: The world’s rarest foods and why we need to save them, Saladino argues that it has also pushed thousands of little-known foods, many with beneficial characteristics or rich historical and cultural significance, to the brink of extinction.
    “The human diet has undergone more change in the last 150 years (roughly six generations) than in the previous one million years (around 40,000 generations),” he writes. This is worrisome, because restricting ourselves to such a narrow range of varieties diminishes the genetic variation that might protect crops and livestock from disease.
    It also narrows the diversity of our gut microbiome, which is vital for our health and well-being, and risks the loss of entire culinary traditions forever. As Saladino puts it, “where nature creates diversity, the food system crushes it”.
    Through a narrative that weaves science and history with stories spanning every corner of the globe, Saladino makes an urgent call to protect the world’s rare foods. The alternative, he warns, is a future where we lose our grip on nature and the vital services it provides, perhaps permanently.
    The book is split into 10 parts, each focusing on a different category: wild foods (hunted or foraged); cereals; vegetables; meat; fish and seafood; fruit; cheese; alcohol; stimulants (tea and coffee) and sweet foods. In every chapter, Saladino highlights a few ingredients and traces their origins, meeting the people who are championing food biodiversity. Often, these individuals represent the last line of defence between a food and its extinction.
    Saladino covers so much ground that it is hard to touch on even a fraction of the foods he explores. Just one example of a rare food with a remarkable story to tell is Hadza honey, foraged by some of the few remaining hunter-gatherer societies – the Hadza people of Tanzania.
    Through a relationship forged over millennia, the Hadza have learned to work together with honeyguide birds so both can reap the rewards of the nutritious honey found high in baobab trees.
    But this special dynamic is under threat: the rising demand for land for crops and livestock is spilling into Hadza territory, putting their livelihoods at risk and depleting the supply of honey and other wild foods on which they depend. Saladino makes the impact of these potential losses clear, often rounding off a chapter with a moving story that underscores how tragic it would be if these foods ceased to exist.
    Packed full of knowledge about a host of ingredients that you probably didn’t even know existed, Eating to Extinction captures the urgency (and cost) of heading towards a future that is less nutritionally diverse.
    “We cannot afford to carry on growing crops and producing food in ways that are so violently in conflict with nature; we can’t continue to beat the planet into submission, to control, dominate and all too often destroy ecosystems,” Saladino concludes. “The endangered foods in this book helped make us who we are; they could be foods that show us who we become.”

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