Ancient dog DNA reveals 11,000 years of canine evolution

The largest-ever study of ancient dog genomes has revealed a lot about our four-legged friends. The analysis of more than two dozen Eurasian dogs suggests that the animals were domesticated and became widespread well before 11,000 years ago. With so many genomes, the researchers could follow ancient dog populations as they moved and mixed and compare these shifts with those in human populations.

The enigmatic species of the Ediacaran

Animal, vegetable or something else entirely? For decades, researchers were baffled by fossils of bizarre living things that dated back to the Ediacaran period — around half a billion years ago. But recent evidence suggests that some of these alien-like species were in fact animals — including ones that had guts, segmented bodies and other sophisticated features. Researchers are using these finds to re-examine a pivotal event in evolutionary history: the Cambrian explosion.

Tyrannosaur hatchlings were chihuahua-sized

Scans of the first known fossils of embryonic tyrannosaurs reveal that they were about the size of a small dog when born. A lower jaw bone and a foot claw, which were found at different sites in western North America, are thought to be from two babies that were 70 and 90 centimetres long. The embryos were not from Tyrannosaurus rex, but an earlier species of related tyrannosaur that has not been identified.

Subsurface lakes discovered on Mars

Planetary scientists have confirmed the presence of a large saltwater lake under the ice at Mars’s south pole — and have found three more. The discovery was made using radar data from the European Space Agency’s Mars-orbiting spacecraft, called Mars Express. It builds on evidence, gathered two years ago, of the first body of liquid water ever detected on the red planet. The largest, central lake measures 30 kilometres across, and is surrounded by 3 smaller lakes, each a few kilometres wide. Life is able to survive in subglacial lakes in places such as Antarctica, but the lakes on Mars might be too salty. Or they might not be liquid water at all; it’s so cold, they could be slush.

How Neanderthals lost their Y chromosome

Neanderthals’ Y chromosome looks a lot like ours, despite much of their nuclear genome more closely matching a different human lineage, the Denisovans. The mystery persisted because very few complete male Neanderthal genomes have been recovered. Now researchers have used an innovative technique to probe some partial male Neanderthal genomes. The scientists found evidence that early modern human men mated with Neanderthal women more than 100,000 but less than 370,000 years ago, and their sons passed the modern Y through their offspring, replacing the Neanderthal Y.

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This suggests that the Sapiens tribes murdered Neanderthal men and abducted Neanderthal women.

Planet discovered transiting a dead star

Evidence has been found of a planet circling the smouldering remains of a dead star in a tight orbit. The discovery raises the question of how the planet survived the star’s death throes — and whether other planets also orbit the remains.

‘Unexplained’ molecule on Venus hints at life

Phosphine has been detected in Venus’s atmosphere, raising the thrilling question of whether the molecule might be a sign of life on the planet. On rocky planets, life is the only known source of the compound — although it forms without a helping hand near the energetic cores of the gas giants. Life seems impossible on the surface of the Solar System’s hottest world, but the middle of its cloud layer offers a more promising environment in terms of temperature, pressure and presence of water and organic molecules. Even if it’s not a sign of life on Venus, the unexpected observation is exciting.

Star system shreds its planet-forming disc

Astronomers have observed, for the first time, a multi-star system ripping apart the disk of material that could form planets. The three stars of GW Orionis have pulled some of their surrounding gas and dust into a warped disc with tilted rings. The rings could someday form planets with wildly oblique and distant orbits.

Solar cell floats on a soap bubble

Materials scientists have made printed solar cells that are so thin, light and flexible that they can rest on the surface of a soap bubble. Researchers formulated ‘inks’ for each layer of the solar-cell architecture so that they could print the cells on a substrate using an inkjet printer. The technology could one day help us ditch heavy batteries and generate power straight from the Sun for lightweight, flexible devices such as medical patches.

Astronomers detect most powerful black-hole collision yet

Astronomers have detected the most-powerful, most-distant and most-perplexing collision of black holes yet, using gravitational waves. Of the two behemoths that fused when the Universe was half its current age, at least one — weighing 85 times as much as the Sun — has a mass that was thought to be too large to be involved in such an event. And the merger produced a black hole of nearly 150 solar masses, the researchers have estimated, putting it in a range in which no black holes had ever been conclusively seen before.

Betelgeuse dimming explained by dust

Astronomers say they have solved the mystery of why Betelgeuse, one of the sky’s brightest stars, started getting dimmer in 2019. By mid-February this year, Betelgeuse had lost more than two-thirds of its brilliance — a difference noticeable to the naked eye. Some people speculated that this was a sign that the star was approaching the end of its life, but researchers working with the Hubble telescope now say it was probably caused by hot material that the star ejected into space, which then cooled and turned into dust.

The asteroid Ceres seems to have liquid water

The dwarf planet Ceres seemingly has a salty ocean of water beneath its surface. The ocean is the source of mysterious bright areas spotted on the distant world’s surface. Images from NASA's Dawn spacecraft, which dipped to less than 35 kilometres above Ceres’s surface on its 2018 mission, reveal the areas are deposits of mostly sodium carbonate. These were formed as briny water percolated up to the surface and then evaporated.

Scientists crack mystery of the origin of Stonehenge's giant stones

Scientists have solved an enduring mystery about Stonehenge, determining the place of origin of many of the megaliths that make up the famed monument in Wiltshire, England, thanks to a core sample that had been kept in the United States for decades.

Geochemical testing indicates that 50 of Stonehenge's 52 pale-grey sandstone megaliths, known as sarsens, share a common origin about 25 kilometres away at a site called West Woods on the edge of Wiltshire's Marlborough Downs.

Microbes revived after 100 million years

Scientists have managed to wake up microbes that have been buried deep beneath the sea floor — apparently in a dormant state — since dinosaurs walked on Earth. The bacteria were discovered in 100-million-year-old clay samples drilled from beneath the South Pacific. When incubated and given nutrients, the microbes began to feed and multiply.

Neanderthal gene linked to increased pain sensitivity

Neanderthals had a biological predisposition to a heightened sense of pain. A first-of-its kind genome study found that the ancient human relatives carried three mutations in a gene encoding the protein NaV1.7, which conveys painful sensations to the spinal cord and brain. They also showed that in a sample of British people, those who had inherited the Neanderthal version of NaV1.7 tend to experience more pain than others.

Astronomers capture first images of multi-planet system around sunlike star

This is the first star like our Sun to be directly imaged with multiple planets orbiting it. Astronomers have directly observed two systems with multiple planets before, but both have stars that are very different from our Sun. This star, TYC 8998-760-1, is just 17 million years old — much earlier in its life cycle than the Sun. The exoplanets are huge: the inner planet is 14 times as massive as Jupiter and the outer one is 6 times as massive. And both planets orbit many times farther away from their star than Pluto does from the Sun.

Controversial cave discoveries suggest humans reached Americas much earlier than thought

A massive haul of stone tools discovered in a cave in Mexico is evidence that people occupied the area more than 30,000 years ago. The finding suggests that humans arrived in North America at least 15,000 years earlier than had been thought. The discovery is backed up by a separate statistical analysis incorporating data from sites in North America and Siberia. But some researchers are unconvinced. They question the age of the tools, and whether the artefacts are tools at all, rather than objects created by natural processes.

Scientists identify 37 recently active volcanic structures on Venus from radar images

Compelling evidence contradicts what scientists had long thought about Venus — that it was geologically dormant for the past half billion years because it lacked plate tectonics similar to Earth.

Cosmic map only deepens expansion mystery

A map of the early Universe has reinforced a long-running conundrum in astronomy over how fast the cosmos is expanding. The data support previous estimates of the Universe’s age, geometry and evolution. But the findings clash with measurements of how fast galaxies are flying apart from each other. They predict that the Universe should be expanding at a significantly slower pace than is currently observed.

Polynesians and South Americans made contact around AD 1200

Traces of Native American ancestry have been found in the genomes of modern inhabitants of some Polynesian islands, suggesting that ancient islanders met and mixed with people from South America hundreds of years ago. Researchers analysed the genomes of more than 800 people from 17 Pacific islands and 15 Native American groups on the Pacific coast. The team looked at the length of shared DNA segments — which shorten in successive generations — to determine that people from Polynesia and South America mingled around 800 years ago. Whether Polynesians voyaged to the coast of the Americas, or people from South America made the trip to the islands, is still up for debate.

‘Quasiparticles’ show up in the lab

Physicists have reported what could be the first incontrovertible evidence of the existence of particle-like objects called anyons, first proposed more than 40 years ago. Anyons are the latest addition to a growing family of phenomena called quasiparticles, which are not elementary particles but collective excitations of many electrons in solid devices. Their discovery — made using a 2D electronic device — could represent the first steps towards making anyons the basis of future quantum computers.

The heaviest known neutron star — or the lightest known black hole

Gravitational-wave observatories have witnessed a black hole, 23 times as massive as the Sun, gobbling up an enigmatic object. At 2.6 solar masses, it is thought to be too large to be a neutron star, the only other type of orb that current detectors are sensitive to. But if it is a black hole, it would be the lightest ever observed. The massive stars that collapse to form black holes should leave behind remnants at least twice that size, standard astrophysical models suggest. Astronomers tried to find clues by looking for light from the merger, but to no avail.

Neutrinos reveal final secret of Sun’s nuclear fusion

The theories for why the Sun shines date back to the 1930s, but one crucial bit of evidence was missing. Now, physicists have found direct evidence for a type of reaction, involving carbon and nitrogen nuclei, in which four protons fuse into a helium nucleus. The smoking gun? Neutrinos, elementary particles the reaction releases. These zip straight out from the Sun’s core, reaching Earth just 8 minutes later. The carbon–nitrogen pathway is not the only type of fusion in the Sun, and it’s not even the main one — neutrinos from all the other reactions had been detected before — but it is thought to be the dominant energy source for larger stars.

Vast neolithic circle of deep shafts found near Stonehenge

Archæologists have discovered a 2-kilometre ring of prehistoric shafts about 3 kilometres from Stonehenge. There are at least 20 of the 4,500-year-old shafts, each more than 5 metres deep and 10 metres in diameter. The startling discovery, in one of the world’s most studied archæological landscapes, comes thanks to modern techniques including ground-penetrating radar.

Dark Matter Experiment Finds Unexplained Signal

The world’s most sensitive dark-matter experiment might have found a hint of the stuff — although the data it has collected so far could be a statistical fluctuation or a spurious signal. The data collected in 2017-18 by the underground XENON1T experiment have revealed an excess in the number of particles hitting its liquid xenon, with a relatively low energy. The finding suggests the possible existence of a hypothetical particle called the axion. But another possible explanation is the presence of radioactive impurities. An upgraded version of the detector called XENONnT could solve the riddle next year.

Bizarre nearby star offers clues to origins of mysterious fast radio bursts

For a fraction of a second in late April, a hyper-magnetised star in the Milky Way suddenly blasted out radio energy. Now scientists say that this sudden, strange blip could help to explain one of astronomy’s biggest puzzles: what powers the hundreds of other mysterious fast radio bursts (FRBs) that have been spotted much farther away in the Universe. Many astronomers think that fast radio bursts — brief but powerful cosmic flashes that flare for just milliseconds — come from magnetars, but haven’t found the link.

Archæologists discover 'amazing' details of Roman city

Archaeologists have mapped a full ancient city with ground-penetrating radar. Falerii Novi, a 30-hectare settlement near Rome that was occupied between 241 BC and AD 700, is now almost entirely buried under agricultural land. The team towed their radar antennas with a quad bike. Their finds include a mysterious public monument — possibly linked to pre-Roman religions — and an extensive network of water pipes that was evidently planned and laid before the city was built.

Oldest Mayan monument ever found

A huge artificial plateau that is 1.4 kilometres long and 10–15 metres high has been discovered in Mexico. Archaeologists spotted the monumental construction from the air using lidar, a remote-sensing method that maps the ground using lasers. Dubbed Aguada Fénix, the extensive structure was built between 1000 and 800 BC, and precedes the peak of the Maya empire by more than a millennium.

Revolutionary microscopy sees individual atoms for first time

A game-changing technique for imaging molecules has produced its sharpest pictures yet — and, for the first time, has discerned individual atoms in a protein. The cryo-electron microscopy breakthrough, reported by two laboratories late last month, will ultimately help researchers to understand how proteins work in health and disease, and will lead to better drugs with fewer side effects.

Ancient DNA offers clues to physical origins of Dead Sea Scrolls

DNA fingerprinting is helping researchers to understand the patchwork of archæological fragments known as the Dead Sea Scrolls. Through genetic analysis, researchers have been able to reconstruct the origin of some of the ancient parchments. In particular, they realised that two pieces once considered part of the same manuscript were in fact made from different animal hides — one from sheep and the other from cow.

Topological insulators enter the fourth dimension

Physicists have created a virtual crystal with four spatial dimensions that acts as a topological insulator — a material that conducts electricity on only its outer boundary. To do so, the team wired up connections among electrical circuits to simulate those in a four-dimensional (4D) crystal. (Just as cubes have six square faces, hypercubes have eight cubic ‘faces’ — so when hypercubes are stacked in 4D, each one is in contact with eight neighbours.) A similar scheme could extend to even more dimensions of space, leading to the observation of new phenomena. Exotic topological insulators could find applications in future quantum computers.

The most ancient land animal ever found

An inch-long creature similar to a millipede looks to be the oldest animal known to have lived on land. Fossil imprints of Kampecaris obanensis from the island of Kerrera in Scotland have been radiometrically dated to around 425 million years ago, in the Silurian period. The arthropod probably fed on decomposing plants on a lakeside. Even earlier land animals, from the Cambrian era, are known to have existed, but only indirectly, from their tracks.

Black Hole Paradoxes Reveal a Fundamental Link Between Energy and Order

The physics of black holes has led to the discovery of a basic link between entropy and energy. The idea began when theoreticians spotted a paradox about Hawking radiation, Stephen Hawking’s calculation that black holes must lose mass over an extremely long time. But if a black hole is even slightly electrically charged, after shrinking for eons it will get to a point at which its electric charge is extremely concentrated — which should prevent it from shrinking further, and perhaps even lead it to split into two smaller black holes. While studying this problem, theoretical physicists stumbled on a formula linking any object’s energy to its entropy — a measure of the number of ways an object’s parts can be rearranged without changing its state.

Astronomers find 'missing' baryonic matter

Astronomers have detected much of the Universe’s ordinary matter, which had long been missing from accounts of its total mass. Not ‘dark matter’ — the mysterious, invisible stuff that makes up the majority of the Universe’s contents. This is normal matter, but it’s spread so sparsely across intergalactic space that more than three-quarters of it is almost undetectable. Using an array of 36 radio telescopes in remote Western Australia, researchers analysed the light from 6 fast radio bursts (FRBs), unusually energetic events that last just milliseconds and originate in other galaxies. The spectrum was sensitive enough to reveal the exceedingly thin matter that the FRBs met in their travels.

Balls of moss move like a flock

Squishy pillows of moss appear to slowly move across glaciers in a coordinated fashion, researchers have found. In a long-term study in Alaska, researchers tagged the rolling ‘glacier mice’ to monitor their motion. The herd seems to move in unison, at a speed of about 2.5 centimetres per day. Their motion didn’t align with the prevailing winds, and they weren’t rolling down a slope — so what propels them is still a mystery.

‘Molecular movie’ shows how electrons rearrange to kick-off a chemical reaction

Scientists in the US and UK are the first to observe electrons rearrange their positions in molecules during the early stages of a light-driven chemical reaction. They did so by firing ultrashort light and X-ray pulses at the molecules to create “movies” of electron motion. The technique promises to shed further light on chemical processes such as bond making and breaking. Their method could also be used to study other ultrafast processes in physics, chemistry, and biology.

Bumblebees Bite Plants to Induce Flowering

When pollen is scarce, bumblebees have their way of extorting more from plants. The insects bite into leaves with their mandibles and proboscises to induce flowering up to one month earlier than normal. Chemical ecologists spotted the unusual behaviour in Bombus terrestris during an unrelated laboratory experiment. Artificial cuts were not as effective, suggesting that some chemicals in the insects’ saliva could play a part.

A planet is born

Astronomers have captured stunning images of a planet forming at the heart of a spiralling disc of gas and dust near AB Aurigae, a star located around 520 light years from Earth. The snap was taken using a near-infrared camera on the Very Large Telescope in Chile. To get better contrast, researchers used a ‘coronagraph’ to block out the star’s light. But even then, it isn’t possible to glimpse the baby planet itself.

A major reboot for carbon dating

Radiocarbon dating is due to be recalibrated using a slew of new data from around the world, including those from tree rings, lake and ocean sediments, corals and stalagmites. The result could have implications for the estimated ages of many finds — such as Siberia’s oldest modern human fossils, which according to the latest calibrations are 1,000 years younger than previously thought.

Corkscrew light promises higher optical-communication data rates

Researchers have demonstrated that a photonic device can produce twisted pulses of light, meaning that their electromagnetic waves swirl in a vortex. The ring-shaped, microscopic ‘tunable vortex microlaser’ is a step towards faster optical communications. Contrary to the properties of light that are commonly used to encode information — wave phase and amplitude — vortices come in discrete types. This makes it harder to mistake one phase for another, which could help to increase the capacity of optical fibres.

Ancient genomes unravel history of East Asia

The first large ancient-genome studies of East Asia suggest that many of its inhabitants descend from two once-distinct populations. Two research groups analysed dozens of genomes from individuals who lived in the region, including what is now China, between 9,500 and 300 years ago. The genomes show that the two populations remained separate for thousands of years, but over time they began interbreeding. This could solve the mystery of how farming spread through the region — it was adopted as farmers and hunter-gatherers mixed. That’s different from what happened in western Eurasia; ancient-genome studies have found that farmers with Middle Eastern ancestry largely replaced hunter-gatherers in Europe.

A glimpse inside δ Scuti stars

Patterns in the vibrations of stars produce a sort of natural music that offers clues to the stars’ internal structure. Astronomers have identified such patterns for some δ Scuti stars, a group for which this music had been elusive.

Pions form a new kind of helium

The ability to make artificial atoms containing exotic particles in place of electrons is giving physicists a new way of probing fundamental interactions. Now researchers have created and interrogated a novel kind of helium atom in which one of the electrons is replaced by a sub-atomic particle known as a pion. The work could shed light on the nature of both pions and neutrinos – tiny, neutral particles for which certain attributes, including mass, remain relatively poorly understood.

Ultracold atomic comagnetometer joins the search for dark matter

A device will use the ‘fifth state of matter’ to search for axions, a relatively neglected candidate for dark matter. The ‘comagnetometer’ consists of two extremely sensitive magnetic-field detectors made from rubidium-87 atoms. The atoms are cooled to near absolute zero to create a Bose–Einstein condensate, so each essentially acts as a single atom. Because they have different spin states that respond differently to magnetic fields, any variation measured by the two detectors could signal the presence of axions.

First full-genome lion family tree

Geneticists have reconstructed the relationships of 20 lions, including several extinct ones, by sequencing their genomes. The results support the idea that lions migrated out of Africa, like humans did. Researchers took samples from both living and dead animals, including two 30,000-year-old cave lions (Panthera leo spelaea) preserved in permafrost in Siberia and Canada’s Yukon territory. The findings reveal details about how lions took over the world — they were once the most globally widespread mammal species — and where genetic diversity has been quashed by shrinking populations.

Closest black hole to Earth found 'hiding in plain sight'

A black hole merely 1,011 light years from our solar system is the closest ever discovered. Astronomers uncovered its presence while studying the binary star system HR 6819 in the constellation Telescopium. The central star orbits a mysterious object every 40 days or so, and the outer star encircles the central star and the object, which has a mass of 4.2 suns. A regular star of that size would shine brightly — so a black hole is the only option.

Dinosaur tail reveals gigantic swimming predator

A new fossil of one of the most unusual dinosaurs, Spinosaurus aegyptiacus, suggests it was a “river monster” powered by a fin-like tail. A new fossil found in Morocco has revealed long spines on the dinosaur’s tail that could have made it work like a giant fin. Hydrodynamic tests with plastic reconstructions of various tail shapes showed that the spinosaurus’s newt-like appendage would produce much more thrust than the tails of other dinosaurs. Spinosaurus aegyptiacus was probably even bigger than Tyrannosaurus rex.

Researchers have built a biological robot

Researchers have built a biological robot that is controlled with part of a rat’s spinal cord. The 6-millimetre robot is made of 3D-printed muscles made of laboratory-grown mouse cells, connected to the section of a rat’s spine that controls the hind legs. Nerves grew from the rat tissue into the muscles and made them contract, and the team could control their ‘Spinobot’ with neurotransmitters. Eventually, the technology could be used in prosthetics, says roboticist Collin Kaufman, but that would probably involve human tissue.

The First Ever Image of Nearby Exoplanet Proxima C?

It’s far from certain, but astronomers might have captured an image of the exoplanet Proxima c, thought to orbit the red dwarf star Proxima Centauri in our nearest neighbouring planetary system. Researchers analysing data from the European Southern Observatory’s Very Large Telescope identified infrared images that seem to show the planet appearing across several years of routine observations. If genuine, the detection could tell us Proxima c’s size and the angle at which it orbits its star. However, some say it could be the result of random noise in the data — unwanted light from artefacts or background stars.

Black Hole Collision Sheds Light

Gravitational-wave astronomers witnessed a merger between black holes of two greatly different sizes, one nearly four times more massive than the other. The unprecedented observation gave them insight into how one of the black holes spins, which had eluded them in previous gravitational-wave experiments examining mergers of equally sized black holes. The new data promise new ways to test Einstein’s general theory of relativity.

Is The Universe Anisotropic?

A map of 850 distant galaxy clusters hints that the Universe might not be uniform. Combining data from US, European and Japanese X-ray space telescopes, researchers have revealed galaxy clusters that were around 30% brighter or fainter than expected, suggesting that their distances had been poorly estimated. Taking these clusters as beacons of the rate of cosmic expansion, the findings would mean that one region is expanding slower than the rest of the Universe, and another is expanding faster.

'Spectacular' artefacts found as Norway ice-patch melts

Ice retreating from a Norwegian mountain pass has uncovered a wealth of artefacts dating back to the Viking era or earlier. Local archaeologists first took note of the pass in 2011, when an ancient woollen tunic was found that could be more than 1,700 years old. The thaw intensified in 2019, revealing everything from stone-built cairns and the remains of a small shelter, to dairy products and reindeer pelts. The ice left many of the items in an exquisite state.

Neutrino clue to antimatter mystery

Physicists have found the strongest evidence yet that neutrinos are fundamentally different from their antimatter counterparts. Researchers produced neutrinos and antineutrinos at an accelerator in Tokai, Japan, and shot them 295 kilometres through the Earth’s crust to the Super-Kamiokande detector. The team found that one flavour of neutrino — muons — morphed into different types of particle at a different rate than did their antimatter twins. If confirmed, the results could help to solve the Universe’s greatest mystery: why there is more matter than antimatter.