‘Entire’ human genome sequence unveiled

An international team of scientists claims to have sequenced the entirety of the human genome, including parts that were missed in the first sequencing of the human genome 20 years ago. That historic draft, and subsequent sequences, have all missed about 8% of the genome. The most recent effort fills in these gaps using new sequencing technologies. It has different limitations, however, including the type of cell line used. The work is described in a preprint, and has not yet been peer reviewed.

Injection of light-sensitive proteins restores blind man’s vision

After 40 years of blindness, a 58-year-old man can once again see images and moving objects, thanks to an injection of light-sensitive proteins into his retina. The trial is the first successful clinical test of a technique called optogenetics, which uses flashes of light to control gene expression and neuron firing. In this case, the person’s damaged photoreceptor cells were supplanted by light-sensitive bacterial proteins, delivered by a virus into cells on his retina. Special goggles simplified incoming visual information from the real world into monochromatic images, to make it more easily detected by the bacterial proteins.

Voyager 1 captures hum between the stars

NASA’s Voyager 1 spacecraft has detected persistent ripples in interstellar plasma, through which it has been travelling since it left the Solar System in 2012. By measuring these waves, astrophysicists have made the first continuous measurements of the density of interstellar plasma, the rarefied medium between the stars.

New Brain Implant Turns Visualised Letters into Text

A brain–computer interface for typing could eventually let people with paralysis communicate at the speed of their thoughts. The device was able to decode, in real time, signals from electrodes implanted in the brain of a 65-year-old man with full-body paralysis as he imagined writing. He was able to mentally type 90 characters per minute — not far from the speed at which the average person that age can type on a smartphone.

‘Spectacular’ Neanderthal find in Italy

The remains of 9 Neanderthals who died between 50,000 and 100,000 years ago have been unearthed in a cave outside Rome. According to archæologists, the Neanderthals were killed by hyenas and dragged into the cave to be devoured. The bones were found in the Guattari Cave, the site of an earlier Neanderthal discovery in 1939.

Minuscule drums push the limits of quantum weirdness

By playing two tiny drums, physicists have provided the most direct demonstration yet of quantum entanglement on larger scales. The aluminium drums are each around 10 micrometres long — barely visible to the naked eye, but enormous by quantum standards. Physicists hit the drums with microwave photons and observed that the membranes moved with such a high degree of correlation that they could no longer be described separately: they were in a quantum-entangled state. In another tiny drum experiment, physicists linked the drums’ properties — although not in perfect sync — to get around some of the measurement restrictions defined by the Heisenberg uncertainty principle. The findings provide evidence that quantum laws still apply in the big world and open the door to future technology built with entangled macroscopic parts.

Arabian structures predate the pyramids

More than 1,000 ancient stone structures dating back 7,000 years have been located in the north-west corner of Saudi Arabia, more than twice the number thought to exist in the area. Mustatil monuments — named after the Arabic word for rectangle — were first identified in the 1970s, but received little academic attention at the time. The structures are between 20 and 600 metres long and might have been used for rituals. If so, the area is the oldest large-scale ritual landscape in the world, predating both Stonehenge and the Egyptian pyramids by thousands of years.

Migration routes of ancient Australians

Scientists have traced the paths that ancient Indigenous Australians probably took as they moved through the mega continent of Sahul some 60,000 years ago. Their models suggest that the first visitors arrived on the shores of western Australia and, within 6,000 years, settled across the entire continent — from the tropical north, now Papua New Guinea, to as far south as Tasmania. Many of the ancient migration routes they modelled seem to match up closely with nineteenth century stock routes and Aboriginal trade lines.

Cellular clocks help explain why elephants are bigger than mice

Biologists are uncovering how tiny ‘clocks’ in our cells might help govern body size, lifespan and ageing. (Mouse cells seem to run faster than human cells, which tick faster than whale cells.) A wave of research is starting to yield answers for one such timepiece: the ‘segmentation clock’. It helps developing embryos to form repeating body segments, such as vertebrae. Researchers want to understand how differences in developmental pace give rise to organisms with such different bodies and behaviours.

Muon results throw theories into confusion

The news earlier this month that the magnetic moment of muons seems to be larger than predicted by the standard model has thrown particle physics into a tizzy. If the discrepancy pans out, it would be the first time that the theory has failed to account for observations since its inception five decades ago. The finding might breathe new life into the theory known as supersymmetry, or SUSY. It could also provide evidence of either a leptoquark or a Z’ boson — hypothetical particles that could, in different ways, help mesh the results with other measurements by the Large Hadron's Collider LHCb detector. In any case, physicists are cautiously excited.

Little Foot fossil shows early human ancestor clung closely to trees

An analysis of the shoulder girdle of a human ancestor that lived millions of years ago suggests that Australopithecus afarensis retained features that helped it to climb in trees, even after developing the ability to walk on two legs. The shoulder blades belong to a near-complete fossil of a specimen dubbed Little Foot, discovered in South Africa in the 1990s.

First flight on Mars

Ingenuity has made the first powered flight on another world. Today, the robot rotorcraft — part of NASA’s Perseverance mission — lifted off from the surface of Mars for 40 seconds. Ingenuity’s counter-rotating carbon-fibre blades spun at more than 2,400 revolutions per minute to lift the craft 3 metres into the air. The US$85-million drone hovered there, and then, in a planned manœuvre, turned 90 degrees and descended safely back to the Martian surface. Software issues that kept the helicopter from transitioning into flight mode had delayed the flight from 11 April.

How many T. rex ever existed?

Over the 2 million or so years during which the species existed, 2.5 billion Tyrannosaurus rex roamed Earth. Palaeontologists used a method employed by ecologists studying contemporary creatures to estimate the population density of T. rex during the late Cretaceous period. The figure has allowed researchers to estimate just how exceedingly rare it is for animals to fossilise.

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If this speculation did not take into account ecological factors such as the different potential numbers of carnivores vs herbivores, then it is a gross exaggeration.

Oldest DNA from a Homo sapiens reveals surprisingly recent Neanderthal ancestry

Scientists have sequenced the oldest Homo sapiens DNA on record, which showed that many of Europe’s first humans had Neanderthals in their family trees. All present-day people whose ancestry isn’t solely African carry Neanderthal DNA, but there are questions about when and how the genetic mixing occurred. Three individuals found in Bacho Kiro Cave in Bulgaria, dated to between 45,900 and 42,600 years old, had “huge chunks” of Neanderthal DNA and probably had Neanderthal ancestors as recently as the past six or seven generations. A woman found in the Zlatý kůň cave in the Czech Republic is thought to be well over 45,000 years old and has Neanderthal ancestry going back considerably longer: 70–80 generations. None of the individuals are related to later Europeans, but the Bacho Kiro people shared a connection with contemporary East Asians and Native Americans. The research adds to growing evidence that modern humans mixed regularly with Neanderthals and other extinct relatives.

Muon result shakes up physics

Muons — massive, unstable cousins of the electron — seem to be more magnetic than the standard model of particle physics predicts. If this result holds up, it could ultimately force major changes in theoretical physics and reveal the existence of completely new fundamental particles. The Muon g – 2 experiment upheld sensational findings, first announced in 2001, that showed the muon’s magnetic moment — a measure of the magnetic field it generates — is slightly larger than theory had predicted.

Scientists Get Closer To Redefining The Length Of A Second

A new generation of atomic clocks are helping scientists to measure time more accurately than ever before. Standard atomic clocks use the oscillation of caesium atoms to measure seconds with great precision. Now, physicists have built a network of clocks based on elements with faster oscillations — aluminium, strontium and ytterbium — to get even closer to a true second.

Artificial life made in lab can grow and divide like natural bacteria

Scientists have identified seven genes that are essential for minimal cells to reproduce like bacteria in the wild. Minimal cells are made in the laboratory and carry only the essential genes needed for cells to function. Biologists at the J. Craig Venter Institute announced that they’d created a line of minimal cells in 2016, but later realised that these didn’t divide symmetrically like bacteria do. Reintroducing seven genes into the minimal-cell genome fixed the issue, providing further insight into how life works on a molecular level.

Long-awaited muon experiment nears moment of truth

A result that has been 20 years in the making could reveal the existence of new particles and upend fundamental physics. Physicists have high hopes that the magnetism of muons, measured in the Muon g – 2 experiment and scheduled to be released on 7 April, will uphold sensational findings first announced in 2001. The project’s earlier results hinted that the muon’s magnetic moment — a measure of the magnetic field it generates — is slightly larger than theory had predicted. If that finding is ultimately confirmed, it could help to reveal what kinds of ephemeral, unknown ‘virtual particles’ swirl in the vacuum.

Gene transfer from plant to insect

A pernicious agricultural pest owes some of its success to a gene pilfered from its plant host millions of years ago. The finding is the first known example of a natural gene transfer from a plant to an insect. It also explains one reason why the whitefly Bemisia tabaci is so adept at munching on crops: the gene that it swiped from plants enables it to neutralise a toxin that some plants produce to defend against insects. Early work suggests that inhibiting this gene can render the whiteflies vulnerable to the toxin, providing a potential route to combating the pest.

New picture of famous black hole reveals its swirling magnetic field

This swirling version of the now-iconic black hole at the centre of the M87 galaxy reveals the nature of the region’s magnetic field. The image was produced by the Event Horizon Telescope (EHT) — which in 2019 produced the first-ever image of a black hole. It shows polarised light emitted by jets hurled by the black hole, accelerating along magnetic fields as they go.

3,000-year-old treasures of Sanxingdui

Archæologists in China have unveiled more than 500 artefacts from six ‘sacrificial pits’ in Sanxingdui dating back more than 3,000 years. The site in southwestern Sichuan province provides a glimpse into an ancient civilisation at the heart of what is thought to be the Shu kingdom. The findings include artistic carvings on a bean-sized piece of ivory, and fragments of a golden mask.

Scientists discover why the human brain is the largest ape brain

Scientists have identified a molecular switch that controls brain growth, making human brains three times larger than those of the other great apes. In studies on mini-brains grown in a dish, they were able to tinker with the mechanism to make gorilla brain tissue larger and human brain tissue smaller.

LHC finds tantalising hints of new physics

Researchers at the Large Hadron Collider (LHC) have seen early hints of an undiscovered particle or interaction. More research is needed, but the results suggest an imbalance in how subatomic beauty quarks decay into two flavours of leptons: electrons and muons. If confirmed, that’s a violation of lepton flavour universality as described by the standard model of particle physics.

How the World’s Oldest Wooden Sculpture Is Reshaping Prehistory

The world’s oldest wooden sculpture is even older than previously thought. A new study suggests that the 2.7-metre-tall Shigir Idol was carved more than 12,000 years ago from a tree that was already more than 150 years old. The relic was preserved in a peat bog in the Ural Mountains and is the world’s only surviving Stone Age wood carving. Its complex iconography of geometric patterns and human faces suggests that the region’s ancient societies were more sophisticated than previously thought.

Mars becomes the first inner planet after Earth to have its core measured

NASA’s InSight spacecraft has revealed the size of Mars’s core by listening to seismic energy ringing through the planet’s interior. InSight’s measurement, taken from the Martian surface, suggests that the radius of the Martian core is 1,810–1,860 kilometres — roughly half of Earth’s. That’s larger than some previous estimates, meaning the core is less dense than had been predicted. The only other rocky planetary bodies for which scientists have measured the core are Earth and the Moon. Adding Mars will allow researchers to compare and contrast how the Solar System’s planets evolved.

Archaea fold, twist and contort their DNA in extreme ways

Single-celled archaea wrap their DNA into flexible, Slinky-like coils that open and close like a clamshell does, possibly providing easy access to their genes. Researchers used computer simulations and electron microscopy to observe this genetic contortion in Methanothermus fervidus for the first time.

Evidence of elusive Majorana particle dies

A study that was once trumpeted as evidence for the existence of an exotic quantum state that could revolutionise computing has turned out to be anything but. A 2018 Nature paper, based on work led by researchers at a Microsoft laboratory in the Netherlands, has now been officially retracted owing to what the authors call “insufficient scientific rigour” in the original data analysis. The retraction is a setback for this approach to quantum computing, but some scientists say it should still be possible to create and study the exotic states, known as Majorana fermions, that were the subject of the research.

Giant ice cube hints at the existence of cosmic antineutrinos

A huge neutrino detector in the Antarctic ice sheet might have seen the first evidence of a rare neutrino-interaction process called the Glashow resonance. The IceCube Neutrino Observatory, buried in the deep ice near the Amundsen–Scott South Pole Station, observes eye-wateringly powerful neutrinos produced by sources such as active galactic nuclei and supernovae. The observatory detected a shower of secondary particles that look likely to have been caused by a collision between an electron antineutrino travelling close to the speed of light and an electron in the ice. If confirmed by more observations, the finding provides further confirmation of the standard model of particle physics, proves the existence of cosmic antineutrinos and opens the door to a better understanding of the wild stuff going on in the cosmos.

Gravity measured on the smallest scale ever

Physicists have measured the infinitesimal gravitational force between two tiny gold spheres, each about the size of a sesame seed, separated by a few millimetres. Researchers reduced interference by using a Faraday shield between the masses, and the experiment was performed in a vacuum during the least seismically active time of year. The work could pave the way to a better understanding of fundamental interactions and the quantum nature of gravity.

Bioluminescence found in deep-sea sharks

Scientists have found three species of sharks living in the deep waters off the east coast of New Zealand that glow in the dark. Many marine animals can produce light through a process known as bioluminescence, but this is the first time that the phenomenon has been observed in the kitefin shark (Dalatias licha), the blackbelly lanternshark (Etmopterus lucifer) and the southern lanternshark (Etmopterus granulosus). At a length of up to 180 centimetres, the kitefin the biggest luminous vertebrate known. The glowing underbellies could camouflage the sharks from predators from below, disguise them when approaching prey or help to illuminate the dark ocean floor.

Decades-Long Quest Reveals Details of the Proton’s Inner Antimatter

Physicists have glimpsed an imbalance in the types of antimatter that swim in the sea of quarks and gluons that make up the proton. A shoestring experiment 20 years in the making, called SeaQuest, has found that there are more down antiquarks than up antiquarks in the proton sea: on average, 1.4 down antiquarks for every up antiquark. The asymmetry could help to decide which of the competing theoretical models of the proton will come out on top.

Life-size kangaroo is Australia’s oldest discovered art

A kangaroo painted in red ochre in a rock shelter in remote northwestern Australia is at least 17,100 years old — the oldest rock art yet dated on the continent. It’s difficult to determine the age of Australian rock art because the region’s ancient artists didn’t tend to use organic materials that can be radiocarbon dated. In this case, researchers analysed fossilised mud-wasp nests laying over and under the art. Alongside the kangaroo, the richly decorated cave includes images interpreted as a boomerang, a reclining human figure and a 3-metre-long snake.

No sign of Planet Nine

The hypothesis that there is a giant planet at the fringes of the Solar System has been dealt a blow by an analysis of distant, icy objects. The findings cast doubt on the evidence that the six trans-Neptunian objects (including Pluto) are under the gravitational pull of a huge planet. The research doesn’t rule out the possibility of a ninth planet orbiting the Sun, and astronomers need more data to put the debate to rest.

Million-year-old mammoth genomes shatter record for oldest ancient DNA

Mammoth teeth preserved in eastern Siberian permafrost have produced the oldest DNA on record. The DNA was extracted from tooth specimens that are up to 1.6 million years old. The DNA identifies a new kind of mammoth that gave rise to a later North American species. The research pushes the technology close to its limits. Once an organism dies, its chromosomes shatter into pieces that get shorter over time. Eventually, the DNA strands become so small that — even if they can be extracted — they lose their information content. The mammoth teeth were preserved in the constant cold of permafrost, which slows DNA fragmentation.

Three quantum devices linked in a network

Physicists have taken a major step towards a future quantum version of the Internet by linking three quantum devices in a network. Although the network doesn’t yet have the performance needed for practical applications, it demonstrates a key technique that will enable a quantum Internet to connect nodes over long distances. A quantum Internet would enable ultrasecure communications and unlock scientific applications, such as new types of sensors for gravitational waves.

Evidence of Unknown Human Species Found in DNA of Melanesians

Scientists found traces of a previously unknown, long-extinct human species hidden in the DNA of today's Melanesians. The two ancient hominid species whose DNA traces scientists expected to find were the Neanderthals and Denisovians. But the results of the study showed something else.

Researchers rethink life in a cold climate after Antarctic find

Sponges and other animals have been discovered on a boulder under 900 metres of ice and 500 metres of water in Antarctica. The creatures were spotted by chance by an underwater camera, after researchers drilled through the Filchner-Ronne ice shelf to obtain a sediment core from the sea bed. No sunlight reaches the animals, and they are thought to live on food carried hundreds of kilometres from the nearest light.

Stonehenge Built From An Earlier Stone Circle?

Stonehenge might have been built from an earlier stone circle: Waun Mawn in west Wales. Stonehenge’s majestic bluestone pillars had already been traced to their source. The stones were excavated from quarries in Wales as early as 3400 BC, about 500 years before Stonehenge was built. Now, researchers have used carbon dating and other techniques to suggest that similar stones that once stood in Waun Mawn were removed at just about the time the first construction at Stonehenge began. The findings further develop a picture of an interconnected society centered on the Irish Sea that flourished in the fourth century BC.

Life on Venus claim faces strongest challenge yet

Two papers have dealt a fresh blow to the idea that Venus’s atmosphere might contain phosphine gas — a potential sign of life. In one study, researchers analysed data from one of the telescopes used to make the phosphine claim and could not detect the gas’s spectral signature. In the other, they calculated how gases would behave in Venus’s atmosphere and concluded that what the original team thought was phosphine is actually sulphur dioxide, a gas that is common on Venus and is not a sign of possible life. Still, the case isn’t closed yet. The new studies argue against the presence of phosphine, but can’t entirely rule it out.

The largest genome of any animal sequenced so far

The Australian lungfish (Neoceratodus forsteri) has the largest animal genome ever sequenced. The fish has a whopping 43 billion base pairs, around 14 times longer than the human genome — although most of its genome is made up of non-coding and repeating regions. A genomic analysis confirms that the surface-breathing fish are the closest living relatives of land vertebrates that last shared a common ancestor around 420 million years ago.

The forces that squeeze and pull life into shape

An embryo develops from a sphere of cells thanks, in part, to the forces that squeeze, bend and tug the growing animal into shape. Even when it reaches adulthood, its cells will continue to respond to pushing and pulling — by each other and from the environment. Yet how bodies and tissues take form remains one of the most important, and still poorly understood, questions of our time. Researchers have begun to define the mechanisms by which cells sense, respond to and generate forces using innovative tools and techniques, both in vitro and in whole animals.

Pulsars hint at sea of gravitational waves

Astronomers might have spied their first hint of gravitational waves made by merging supermassive black holes. For more than a decade, the NANOGrav collaboration has been monitoring radio waves from 45 spinning stars, known as pulsars. Tiny deviations in the arrival times of the waves could reveal the cumulative ripples in space-time caused by merging supermassive black holes across the Universe. An analysis of more than 12 years of data shows preliminary evidence for the effect.

Cuttlefish think ahead, ‘marshmallow test’ reveals

Eat one marshmallow now — or wait a few minutes and get two? This famous behavioural test is supposed to distinguish between impulsive children and those more likely to think through their actions — and thus, do better in academic life. Now, scientists have given a similar test to cuttlefish, The New York Times reports. Replacing the marshmallow with a shrimp, researchers gave the molluscs the option to eat two shrimp now — or eat one shrimp with the promise of an extra reward. Most of the cuttlefish chose the latter, researchers report in Royal Society Open Science. The find suggests that — like people — these molluscs can delay gratification if they think it will pay off in the long run.

Bean plants show signs of intent

Research suggests that at least one type of plant – the french bean – may be more sentient than we give it credit for: namely, it may possess intent.

Strange dinosaur has scientists enthralled

About 110 million years ago along the shores of an ancient lagoon in what is now north-eastern Brazil, a two-legged, chicken-sized Cretaceous period dinosaur made a living hunting insects and perhaps small vertebrates like frogs and lizards. This dinosaur, called Ubirajara jubatus, possessed a mane of hair-like structures while also boasting two utterly unique, stiff, ribbon-like features probably made of keratin – the same substance that makes up hair and fingernails – protruding from its shoulders.

3300-year-old baboon skull may tell of mysterious ancient kingdom

Archæologists might have found the first hard evidence of a mysterious land called Punt where ancient Egyptians traded for precious metals and exotic animals. A mummified baboon (Papio hamadryas), taken from an ancient Egyptian temple and currently residing in the British Museum, seems to be the first known traveller from this antique land. The distinctive ratio of strontium isotopes in the baboon’s teeth show that it was born in an area that encompasses much of present-day Ethiopia, Eritrea and Djibouti, and portions of Somalia and Yemen — just where most archæologists think Punt was located.

First peek inside Mars reveals a crust with cake-like layers

NASA’s InSight mission has finally peered inside Mars, marking the first time scientists have directly probed the inside of a planet other than Earth. Seismologists are using marsquakes to map the red planet’s interior, measuring differences in how seismic waves move through its structure to determine the make-up of the planet’s geological layers. The new data show that Mars’s crust is made up of either two or three layers. In the coming months, scientists will report on measurements taken even deeper, ultimately revealing information about the planet’s core and mantle.

Photon-based quantum computer does a calculation that ordinary computers might never be able to do

A team in China claims to have made the first definitive demonstration of ‘quantum advantage’ — exploiting quantum mechanics to perform computations that would be prohibitively slow on classical computers. The team achieved within a few minutes what would take half the age of Earth on the best existing supercomputers.

Reversal of biological clock restores vision in old mice

Researchers have restored vision in old mice and in mice with damaged retinal nerves by resetting some of the thousands of chemical marks that accumulate on DNA as cells age. The work suggests a new approach to reversing age-related decline: reprogramming some cells to a ‘younger’ state in which they are better able to repair or replace damaged tissue. Researchers took genes known to cause cells to revert to a stem-cell-like state and inserted them into mice using a virus. They then triggered the genes to see whether they would help injured eye cells or those degraded by age.

Study finds indications of life on Doggerland after devastating tsunamis

Around 8,200 years ago, a series of huge tsunamis, triggered by enormous underwater landslides off the coast of Norway, severed what is now Britain from continental Europe. But scraps of the inundated area — known as Doggerland — might have survived and later been settled, say archæologists. They analysed the topography of the land now beneath the North Sea and sedimentary cores that revealed evidence of the cataclysmic Storegga slides. The land that remained could have offered the first Neolithic farmers step-stones from the continent to Britain thousands of years later.

‘The Sistine Chapel of the ancients’

Archæologists have documented tens of thousands of ice-age paintings that stretch across nearly 13 kilometres of cliff face in Colombia. They depict patterns, figures, handprints and animals, including now-extinct species such as mastodons, palæolamas, giant sloths and ice-age horses. The discovery was made last year but is only now being revealed to coincide with the release of a television documentary that includes the art. The paintings are in the Serranía de la Lindosa, near the Chiribiquete national park, another site that is rich with prehistoric art.

Gigantic leap in solving protein structures

An artificial-intelligence (AI) network has made enormous progress in solving one of biology’s grandest challenges — determining a protein’s 3D shape from its amino-acid sequence. The breakthrough is likely to transform biology, say scientists, and should aid in drug design.