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    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.

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    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
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    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.

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    “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
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    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.

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    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.
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    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

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    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.
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    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

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    Avi Loeb interview: Could ‘Oumuamua be alien technology after all?

    Harvard astrophysicist Avi Loeb has drawn criticism for suggesting a weird object passing through the solar system could be an alien spacecraft. But he insists we must keep an open mind when nature throws us a curveball

    Space 10 February 2021
    By Leah Crane

    Rocio Montoya

    IN 2017, something strange came hurtling through our cosmic neighbourhood. Astronomers only spotted it once it was already on its way out, so they didn’t get a proper look. But from the few observations we did get, it was clear that the object wasn’t from around here – its trajectory indicated that it came from another star system. It was dubbed ‘Oumuamua, which means “scout” in Hawaiian, and categorised as the first interstellar object we have ever seen in our cosmic neighbourhood.
    Not long after ‘Oumuamua was spotted, Avi Loeb, an astrophysicist at Harvard University, made waves by proposing that it may be a piece of alien technology. “‘Oumuamua may be a fully operational probe sent intentionally to Earth vicinity by an alien civilization,” Loeb wrote in a pre-print paper.
    It is certainly weird. Observations suggested it is likely to be either flat or cigar-shaped, tumbling end over end every 7 hours or so and accelerating at a pace seemingly greater than could be accounted for by gravitational forces alone. Loeb’s colleagues have since come up with various natural explanations for what we glimpsed of ‘Oumuamua’s features, including the idea that it is some sort of giant fractal snowflake. But he is adamant we should at least be open to the possibility that it could be evidence of the existence of extraterrestrial civilisations.
    Loeb has now written a book about it called Extraterrestrial: The first sign of intelligent life beyond Earth. Here, he tells New Scientist about the possibility of advanced alien life and how humans might respond to it.

    Leah Crane: You say … More

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    2700-year-old face cream was made from animal fat and cave ‘milk’

    By Michael Marshall
    A 2700-year-old face cream
    Dr. Bin Han, University of Chinese Academy of Sciences, China

    Some Chinese noblemen were using cosmetic face cream 2700 years ago. Archaeologists have found an ornate bronze jar containing the remains of a face cream, which was made from a mixture of animal fat and a rare substance called moonmilk that is found in caves.
    The discovery is the earliest evidence of a Chinese man using cosmetics, although there is older evidence of Chinese women doing so.
    In 2017 and 2018, Yimin Yang at the University of Chinese Academy of Sciences in Beijing and his colleagues … More

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    Two exoplanet families redefine what planetary systems can look like

    Two tightly packed families of exoplanets are pushing the boundaries of what a planetary system can look like. New studies of the makeup of worlds orbiting two different stars show a wide range of planetary possibilities, all of them different from our solar system.
    “When we study multiplanet systems, there’s simply more information kept in these systems” than any single planet by itself, says geophysicist Caroline Dorn of the University of Zurich. Studying the planets together “tells us about the diversity within a system that we can’t get from looking at individual planets.”
    Dorn and colleagues studied an old favorite planetary system called TRAPPIST-1, which hosts seven Earth-sized planets orbiting a small dim star about 40 light-years away. Another team studied a recently identified system called TOI-178, which has at least six planets — three already known and three newly found — circling a bright, hot star roughly 200 light-years away.
    Both systems offer planetary scientists an advantage over the more than 3,000 other exoplanet families spotted to date: All seven planets in TRAPPIST-1 and all six in TOI-178 have well-known masses and radii. That means planetary scientists can figure out their densities, a clue to the planets’ composition (SN: 5/11/18).

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    The two systems also offer another advantage: The planets are packed in so close to their stars that most are engaged in a delicate orbital dance called a resonance chain. Every time an outer planet completes an orbit around its star, some of its closer-in sibling planets complete multiple orbits.
    Resonance chains are fragile arrangements, and knocking a planet even slightly out of its orbit can destroy them. That means the TRAPPIST-1 and TOI-178 systems must have formed slowly and gently, says astronomer Adrien Leleu of the University of Geneva.
    [embedded content]
    TOI-178’s planets are engaged in a delicate orbital dance called a resonance chain that suggests the system formed gently. This video illustrates this rhythmic dance: as an outer planet completes one full orbit, the inner planets complete multiple orbits. Each full and half orbit is assigned a musical note. When planets align, the notes harmonize.
    “We don’t think there could have been giant impacts, or strong interactions where one planet ejected another planet,” Leleu says. That gentle evolution gives astronomers a unique opportunity to use TRAPPIST-1 and TOI-178 as testbeds for planetary theory.
    In a pair of papers, two teams describe these systems in unprecedented detail. Both buck the trend astronomers expected from theories of how planetary systems form.
    In the TOI-178 system, the planets’ densities are all jumbled up, Leleu and colleagues report January 25 in Astronomy & Astrophysics.
    “In the most vanilla scenario, we expect that planets farther from the star…would have larger components of hydrogen and helium gas than the planets closer in,” says astrophysicist Leslie Rogers of the University of Chicago, who was not involved in either study. The closer to the star, the denser a planet should be. That’s because farther-out planets probably formed where it’s cold, and there was more low-density material like frozen water, rather than rock, to begin with. Plus, starlight can strip atmospheres from close-in planets more easily than far-out ones, leaving the inner planets with thinner atmospheres — or no atmospheres at all (SN: 7/1/20).
    TOI-178 flouts that trend entirely. The innermost planets seem to be rocky, with densities similar to Earth’s. The third one is “very fluffy,” Leleu says, with a density like Jupiter’s, but in a much smaller planet. The next planet out has a density like Neptune’s, about one-third Earth’s density. Then, there’s one with about 60 percent Earth’s density, still fluffy enough to float if you could put it in a tub of water, and the final planet is Jupiter-like.
    “The orbits seem to point out that there was no strong evolution from [the system’s] formation,” Leleu says. “But the compositions are not what we would have expected from a gentle formation in the disk.”
    TRAPPIST-1’s planet septet, on the other hand, has an eerie self-similarity. Each world is roughly the same size as Earth, between 0.76 and 1.13 times Earth’s radius, astrophysicist Eric Agol of the University of Washington in Seattle and colleagues reported in 2017 (SN: 2/22/17). Plus, at least three of them appear to be in the star’s habitable zone, the region where temperatures might be right for liquid water.
    Now, Agol, Dorn and colleagues have made the most precise measurements of the TRAPPIST-1 masses yet. All seven worlds are almost identical to each other but slightly less dense than Earth, the team reports in the February Planetary Science Journal. That means the planets could be rocky yet have a lower proportion of heavy elements such as iron compared with Earth. Or it could mean they have more oxygen bound to the iron in their rocks, “basically rusting it,” Agol says.
    TRAPPIST-1’s seven planets seem to have similar compositions to each other, but different from Earth. They could have an Earthlike makeup but with a smaller iron-rich core (center), or have no core at all (left). They could also have deep oceans (right), but the inner three planets are probably too hot for that much water to last.JPL-Caltech/NASA
    TRAPPIST-1’s seven planets seem to have similar compositions to each other, but different from Earth. They could have an Earthlike makeup but with a smaller iron-rich core (center), or have no core at all (left). They could also have deep oceans (right), but the inner three planets are probably too hot for that much water to last.JPL-Caltech/NASA
    Oxidized iron wouldn’t form a planetary core, which could be bad news for life, Rogers says. No core might mean no magnetic field to protect the planets from the star’s damaging flares (SN: 3/5/18).
    However, it’s not clear how to form coreless planets. “There are propositions for how to form such planets, but we don’t actually have one candidate in the solar system where we see this,” Dorn says. The analogs in the solar system are all asteroid-sized bodies much less massive than Earth.
    Astronomers may soon get a better handle on the compositions of TRAPPIST-1’s planets. The James Webb Space Telescope, set to launch in October, will probe the planets’ atmospheres (if they have any) for signs of chemical elements that would reveal in more detail what they’re made of.
    The TRAPPIST-1 planets’ similarities to each other are not as surprising as the differences among TOI-178’s planets, Rogers says. But they’re still unexpected. If all the planets have identical compositions, then any formation model needs to explain that, she says.
    While these systems challenge astronomers’ views of what sorts of planets are possible, Dorn says, it will take discovering more multiplanet systems to tell how weird they truly are. More