More stories

  • in

    Don’t Miss: Capitalism vs environmentalism at London’s Science Museum

    PixabayExplore
    Is Capitalism Compatible With Environmentalism asks broadcaster Jon Snow of a panel of experts in climate science, policy and economics at the Science Museum in London. Watch online at 7.30 pm on 26 February.

    Read
    Hidden Wonders are revealed by French physicist étienne Guyon and his co-authors in a fascinating book that explores the mathematical elegance in everyday objects and physical mechanisms, from crumpled paper to sandcastles.
    Courtesy of EPIX
    Watch
    Pennyworth, on Amazon Prime Video from 28 February (StarzPlay subscription required), starts its second counterfactual season with Batman’s future butler still in the UK, embroiled in a devastating civil war.
    More on these topics: More

  • in

    Do telomere length tests really reveal your biological age?

    Curiosity about how well our bodies are ageing has fuelled an industry around telomere length tests, but the much touted “biological clock” in our DNA isn’t what we thought

    Life 17 February 2021
    By Marta Zaraska
    Martin Leon Barreto

    WHEN David Nurse turned 30, he wanted to find out how his biological age compared with his chronological one. A life coach with the US National Baseball Association, he hoped that the ultra-healthy lifestyle he advocates to players had kept his own body young and healthy, too. So he took a test to assess the length of his telomeres. It revealed his biological age to be 28 years. That was in 2017. Two years later, he took another test. “I was down to 25, so that was great,” he says.
    If you google “telomeres”, you are likely to find them described as an ageing clock. They are segments of DNA at the ends of each chromosome that become shorter every time a cell divides. If this shortening happens slowly, it suggests that your body is wearing well. Say you are a 60-year-old with telomeres as long as those of an average 50-year-old, your mortality risk is equivalent to that of someone 10 years younger – or so the story goes. Increasing numbers of people want this information, and many companies offer tests like the one Nurse took, together with various pills claimed to lengthen your telomeres and, in turn, your lifespan.
    If only it were that simple. We are now discovering that telomeres are an unreliable ageing clock, which raises questions about the validity of ageing tests based on them. The links between telomere length and lifestyle choices also aren’t as straightforward as we once thought. In fact, long telomeres can even be bad news. Nevertheless, there are some surprising ways we can look after our … More

  • in

    Stonehenge was built with bits of an older Welsh Stone Age monument

    By Alison George
    The arc of former standing stones at Waun Mawn
    A. Stanford
    The origins of Stonehenge have long been a mystery. Now new discoveries show that the iconic monument may have started as a stone circle in Wales that was then dismantled and rebuilt 280 kilometres away at its current location on Salisbury plain. This is the conclusion of a team of archaeologists who uncovered the remains of what appears to be Britain’s third-largest stone circle, in the Preseli hills of west Wales.
    Stonehenge was built in several different phases between about 3000 and 2000 BC, starting with a large circular ditch and bank together with a circle of 2-metre-high bluestones just inside. Later, these bluestones were moved, and bigger structures made from boulders known as sarsens were built.

    Advertisement

    In 2015, a team led by Mike Parker Pearson at University College London revealed that the bluestones were extracted from quarries in the Preseli hills, some 280 kilometres away in west Wales. The team then looked for evidence of stone monuments close to these quarries, as the Neolithic people who extracted Stonehenge’s bluestones might have constructed stone circles here too.
    The archaeologists excavated at a site called Waun Mawn, which had four large stones seemingly placed in an arc. They uncovered evidence of a further six holes that each originally held a stone, indicating that there had once been a stone circle with a large diameter at the site.
    “The arc did continue – that was a really important moment,” says Parker Pearson. Extrapolating from these positions, the team estimates that the completed circle probably had 30 to 50 stones, though arranged more haphazardly than the original bluestone circle at Stonehenge.

    A number of strands of evidence suggest that stones from Waun Mawn formed part of the original stone circle at Stonehenge. Dating studies showed that the Waun Mawn stone circle was created between 3600 and 3200 BC, a few hundred years before the first stages of construction at Stonehenge, and the types of stone at the two sites match.
    One of the stone holes at the Welsh site has an unusual pentagonal shape, similar in shape and size to that of bluestone 62 at Stonehenge. “It could have been in that hole. It’s not categorical proof, but it is really very suggestive,” says Parker Pearson.
    The sizes of the two circles also match. “There are only two Neolithic monuments in Britain with the same diameter of 110 metres, and that’s the outer ditch of Stonehenge and the Waun Mawn diameter,” he says. Stonehenge is famous for aligning with the midsummer solstice sunrise, and the new evidence at Waun Mawn suggests it had this alignment too.

    “It’s a really interesting study that shows some nice arguments for a link between both stone circles,” says David Nash at the University of Brighton, UK, who wasn’t involved with the excavations in Wales, but, who last year published a study identifying the origins of Stonehenge’s sarsens. For him, the clincher would be to conduct detailed geological analysis of stone fragments found at Waun Mawn to see if they are identical to those found at Stonehenge.
    Others are less convinced. “They’ve got a ragbag of stones and I’m rather sceptical of it being a stone circle,” says Tim Darvill at Bournemouth University, UK, who has carried out many studies of Stonehenge.
    Further excavations are planned at Waun Mawn to clarify the picture. But if Stonehenge was rebuilt from a Welsh stone circle, this could help explain why Neolithic people went to such lengths to construct the iconic megalithic monument. Studies of the isotopes in cremated remains of the earliest people interred at Stonehenge indicate that some of them probably came from west Wales. This has led Parker Pearson to conclude that Stonehenge was constructed to commemorate the ancestors of the original people who lived at Stonehenge.
    The Welsh excavations also shed light on the earliest story of the monument’s origins from 1136, when the chronicler Geoffrey of Monmouth wrote how Stonehenge was built from a dismantled stone circle in Ireland. It seems this tale had a grain of truth, says Parker Pearson.
    Journal reference: Antiquity, DOI: 10.15184/aqy.2020.239
    More on these topics: More

  • in

    Mini brains genetically altered with CRISPR to be Neanderthal-like

    By Ibrahim Sawal
    These mini brains contain a Neanderthal version of a certain gene
    UC San Diego Health Sciences
    Miniature brains grown in the lab are helping to reveal how modern humans survived when other hominins died out.
    Neanderthals and Denisovans are some of our closest relatives. They lived alongside us about 50,000 years ago when modern humans migrated from Africa towards Europe, but they went extinct shortly after we came into contact with them. This might be because modern humans outcompeted and outsmarted them, but it may have just been bad luck.

    Advertisement

    Alysson Muotri at the University of California, San Diego, and his colleagues wanted to know more about how our brains differed from these other hominins and whether this could affect survival. The team compared the genomes of modern humans, Neanderthals and Denisovans and found a total of 61 genes that differed.
    One gene, neuro-oncological ventral antigen 1 (NOVA1), particularly caught their eye. The gene is specifically active during brain development and influences the developing nervous system. The team found that the modern human NOVA1 gene differed from the Neanderthal and Denisovan version by a single base pair
    To find out more, the team grew their own ancient human-like brains. They used CRISPR genome editing to change the modern NOVA1 gene in human stem cells to mimic the Neanderthal and Denisovan version, then prompted the cells to develop into a Neanderthal or Denisovan-like brain organoid – a small, simplified version of the organ consisting of clusters of brain cells in a dish. They did the same with standard human stem cells.

    As they matured, the ancient human organoids were smaller in diameter, had a more wrinkled cell surface and their cells multiplied more slowly than the modern human ones. “They are quite distinct from modern humans, suggesting that single base alteration can change brain development,” says Muotri.
    This alteration also changed the expression of 277 genes compared with the modern human organoids, and caused 113 alternative splicing events – a process that causes one gene to code for multiple proteins, many of which were linked to brain development and synapse formations.
    “The fact that virtually all modern humans now carry the modern version of the gene, strongly suggests that the alteration is a benefit to our species,” says Muotri. “If I might speculate, it might suggest that individuals carrying the Neanderthal NOVA1 alteration have a potential different way to process information,” he says, and this therefore may have affected their survival.

    Tony Capra at the University of California, San Francisco, says he is excited about these new methods because it allows us to directly test Neanderthal brains. “As it progresses, we will be able to evaluate how the Neanderthal genome worked in more and more complex and realistic models,” he says.
    However, because Muorti and his team used a modern human genome with a single change, Capra says this doesn’t truly reflect the entire Neanderthal or Denisovan genome. “It is unlikely that a single “magic” genetic change produced a dramatic positive change in these traits,” says Capra. He says there are many parts of our genome that contribute to cognition and that evolution may have acted on multiple variants with smaller effects.
    Journal reference: Science, DOI: 10.1126/science.aax2537
    Sign up to Our Human Story, a free monthly newsletter on the revolution in archaeology and human evolution More

  • in

    Listen to the oldest known conch shell horn from 18,000 years ago

    By Karina Shah

    A conch shell found in a cave used by the Magdalenian people of the late Upper Palaeolithic was originally thought to be a cup, but a new analysis suggests they used it as a kind of horn. That would make it the earliest known conch shell horn.
    Gilles Tosello at the University of Toulouse in France and his colleagues were investigating objects and cave art found in Marsoulas Cave in the Pyrenees mountains. They revisited a conch shell that was discovered in 1931.
    The shell is 31 centimetres long and 18 centimetres wide and once belonged to a large sea snail of the species Charonia lampas that likely lived on the coast of France or Spain.
    It has a small narrow hole drilled into the the point of the shell called the apex, and is decorated with fingerprint-shaped ochre red markings.

    Advertisement

    “We are pretty sure that this shell was transformed by human action, on the contrary to what was first published in the 1930s,” said Tosello at a press conference on 9 February. Its original discoverers suspected the conch shell was a ceremonial drinking cup.
    Tosello and his team came to a different conclusion after examining the inside of the shell with CT scanning and a tiny medical camera.
    “The broken part of the apex is very narrow, and the hole inside is perfectly round with a regular edge,” he said. The hole in the apex was most likely drilled to make way for some kind of mouthpiece, such as a small hollow bone to blow into, to protect the lips of the musician.

    To test the hypothesis that this was used as an instrument, the team enlisted the help of a horn player to see if they could play the conch shell – the horn player produced three notes close to C, D and C sharp.

    Along with the decorative ochre markings – which match paintings found on the walls of the original cave – there are smears of a brown, organic residue around the conch shell. Although there is not enough to determine what the residue is, it was probably used as a sort of glue to fix the mouthpiece into the shell, says Tosello.
    The team have now produced a 3D model of the conch shell to investigate how it was used by the Magdalenian people as a musical instrument, without damaging the original artefact.
    It’s not surprising that the Magdalenian people played instruments as music is an inherent part of any cultural system, says Francesco d’Errico at the University of Bordeaux in France.
    Journal reference: Science Advances, DOI: 10.1126/sciadv.abe9510
    Sign up to Our Human Story, a free monthly newsletter on the revolution in archaeology and human evolution
    More on these topics: More

  • in

    Don't Miss: Netflix's Tribes of Europa, a German near-future sci-fi

    Paul SayedListen
    Octave of Light, featuring soprano Beth Sterling, is an album of exoplanet music by David Ibbett, guest composer at Fermilab in Illinois, and astronomer Roy Gould, who have turned exoplanet spectra into musical chords.

    Read
    The Raven’s Hat by Jonas Peters and Nicolai Meinshausen is a series of engaging games that seem unsolvable — until you translate them into mathematical terms. Hours of fun for anyone who took maths seriously at school.
    Netflix
    Watch
    Tribes of Europa, a near-future German sci-fi series on Netflix, follows siblings Kiano, Liv, and Elja, who are fighting for their lives on a continent split into warring tribal states. Available from 19 February.
    More on these topics: More

  • in

    Build colonies or save spacecraft in the best video games set on Mars

    As real spacecraft begin to arrive at the Red Planet, let’s celebrate with Mars-based games like Surviving Mars, where you build colonies, and Tharsis, where you captain a doomed spacecraft

    Space 10 February 2021
    By Jacob Aron
    A Martian base explodes in Red Faction: Guerrilla
    Deep Silver Volition
    Red Faction: Guerrilla
    Deep Silver Volition

    Advertisement

    PC, PlayStation 3 and 4, Xbox 360 and One, Nintendo Switch
    Kerbal Space Program
    Squad
    PC, PlayStation 4, Xbox One
    Tharsis Choice Provisions PC, PlayStation 4, Xbox One, Nintendo Switch
    THIS month sees a trio of real-life spacecraft arrive at Mars, so in honour of their voyages I thought I’d run through my own jaunts to the Red Planet in game mode.

    Mars is a common locale for many first-person shooters, with games in the Doom, Destiny and Call of Duty series all featuring levels on its dry, dusty surface, but they rarely do very much interesting with the setting.
    One exception is Doom Eternal, which I reviewed last year. As you fight your way through endless demon hordes, it becomes clear you must journey to hell through a portal at the centre of Mars. How? Why, by commandeering a massive laser on Mars’s moon Phobos and blasting a gigantic crater into the planet’s surface.
    Speaking of blowing things up on Mars, the Red Faction series makes a selling point of having “destructible terrain”, essentially letting you knock down walls and buildings to progress through the game. This is still a rarity in video games, partly because of the technical difficulties in rendering destruction on the fly, but also because letting players destroy everything makes it hard to impose any narrative structure.
    My favourite of the series, Red Faction: Guerrilla, solves this by throwing narrative structure out of the window, then throwing the window out of the window. You play Alec Mason, a freedom-fighter attempting to overthrow the tyrannical rulers of Mars, but forget all that – what matters here is that you are given mining charges, trucks and a really big hammer and then encouraged to destroy everything in sight. It is incredibly satisfying, even if you are setting the course of Martian settlement back decades.
    “Kerbal Space Program lets you build pretty much any spacecraft you can imagine; mine tend to blow up”
    If you fancy something a bit more constructive, Surviving Mars, which I reviewed in 2019, puts you in charge of building a colony from the ground up. I enjoyed the challenges of managing water, oxygen and electricity supplies as I plotted out various domed habitats on the Martian soil. The game is just tricky enough that you feel like you are struggling to survive without it being too disheartening when a bunch of your colonists die in a dust storm.
    Offworld Trading Company is similar but puts you slightly further into the future, with Mars settled and corporations vying to exploit its natural resources. The game is ruthlessly capitalist and sees you exploiting markets to get one over on your rivals or make a hostile takeover.
    If your dreams of being Elon Musk revolve around building rockets rather than becoming a billionaire, Kerbal Space Program is for you. With a bewildering array of capsules, engines and more, you can pretty much construct any spacecraft you can imagine. Whether you can get it off the ground is another matter – mine tend to blow up. Once in orbit, there is a whole solar system analogue to explore, with dusty Duna as Kerbal’s version of Mars.
    Finally, for a darker look at what astronauts heading to Mars might face, there is Tharsis. It is set aboard the first crewed ship to the Red Planet, which has been damaged by a micrometeoroid storm, meaning you have to repair the ship and shepherd the crew to safety. Unusually, the game takes inspiration from board games, so you roll virtual dice to achieve objectives such as putting out a fire. This leaves things slightly more up to chance than I would like, making it hard to strategise, but no one ever said getting to Mars would be easy.
    More on these topics: More

  • in

    How to make a marvellously smooth mayonnaise

    By Sam Wong
    Tetiana Vitsenko/Alamy
    What you need
    1 egg yolk
    1 tbsp lemon juice
    1 tsp Dijon mustard 250 ml vegetable oil
    OIL and water famously don’t play well together. Water is a polar molecule, with a negative charge concentrated around the oxygen atom and a positive charge at the two hydrogen atoms. This means that water molecules attract each other, the hydrogen atoms forming bonds with the oxygen atoms of nearby molecules. Oil, on the other hand, is made from non-polar molecules, which aren’t attracted by the water molecules, so it is hard for them to mingle.
    If you shake … More