First sighting of ‘neutrino fog’ sparks excitement – but is it bad news for dark matter?

For the first time, physicists have observed glimmers of the ‘neutrino fog’, signals from particles called neutrinos that mimic those expected to be produced by dark matter — the mysterious substance thought to make up the bulk of matter in the Universe. That’s exciting for physicists because it means that detectors have become sensitive enough to pick up signals of dark matter. But there’s a catch: the neutrino signals could obscure the dark-matter signals that scientists are so eager to observe.

Neanderthals and sapiens interbred more recently than previously thought

All people, other than those whose ancestry comes solely from sub-Saharan Africa, have some Neanderthal DNA. Now two studies suggest that it entered our genomes virtually overnight, much more recently than was thought. One study finds that modern humans and Neanderthals interbred in a roughly 7,000-year period starting around 50,500 years ago; the other finds that the mixing took place between 45,000 and 49,000 years ago. The results and other insights come in part from the oldest human genomes ever sequenced: a male Homo sapiens found near Ranis, Germany, and a female Homo sapiens whose remains were discovered in a cave at a site called Zlatý kůň in the Czech Republic.

Galaxy could mirror a young Milky Way

Images of a young galaxy captured by NASA’s James Webb Space Telescope have given astronomers a glimpse of what the Milky Way might have looked like when it first formed. The images capture the galaxy, dubbed Firefly Sparkle after its resemblance to the bioluminescent insects, in the process of being assembled from groups of stars around 600 million years after the beginning of the universe.

Google’s new quantum chip achieves accuracy milestone

Google scientists have demonstrated that, with the right error-correction techniques, quantum computers can perform calculations with increasing accuracy as they are scaled up. The newest chip, Willow, has performed ‘below threshold’ quantum calculations — a key milestone in the quest to build quantum computers that are accurate enough to be useful.

Virtual lab powered by ‘AI scientists’ super-charges biomedical research

Researchers have created a virtual laboratory staffed by ‘AI scientists’ — large language models (LLMs) with defined scientific roles — that collaborate to achieve goals set by people. The team trained one LLM to be the work’s principal investigator (PI) and a second to act as a ‘scientific critic’. The ‘PI’ then trained three further LLMs to support the research efforts. Each worked independently, but the group came together for short ‘team meetings’ overseen by a human. When tasked with designing antibody fragments that can bind to the virus that causes COVID-19, the AI team proposed 92 structures in a fraction of the time it would have taken an all-human research group.

Oceans have never existed on Venus

Earth’s neighbour Venus has never had liquid water on its surface. One theory of the rocky planet’s history posited that after being covered by magma, the planet maintained a temperate climate for billions of years, which allowed oceans of water to form. Researchers used the chemical composition of volcanic gases in Venus’s atmosphere to infer the water content of its interior — a barometer of whether it ever had such oceans. They found only a 6% water content in the gases, suggesting a very dry planet that has never had liquid water on its surface.

How close is AI to human-level intelligence?

How close are we to developing an artificial general intelligence (AGI) — a machine capable of the whole range of cognitive tasks that human brains can handle? Some think that the large language models (LLMs) currently out there already have some of the ingredients in place. One point in these models’ favour is their underlying transformer architecture, which can find statistical patterns in a range of information beyond text, such as audio. Yet there are also signs that transformer-based LLMs have limits. For a start, the data used to train the models are running out.

Two ancient human relatives crossed paths 1.5 million years ago

Some 1.5 million years ago, two ancient hominin species crossed paths on a lake shore in Kenya. Their footprints in the mud were frozen in time and lay undiscovered until 2021. Now, analysis of the impressions reveals that they belonged to Homo erectus, a forebear of modern humans, and the more distant relative Paranthropus boisei. The two individuals walked through the lake area within hours or days of each other — leaving the first direct record of different archaic hominin species coexisting in the same place.

Bromalites show how dinosaurs rose to rule Earth

By analysing fossils of poo and vomit, researchers have reconstructed what dinosaurs ate and how this changed over time. The findings give a better understanding of how dinosaurs became so dominant, revealing that their rise, over millions of years, was influenced by factors including climate change-induced shifts in what vegetation was available, which the dinosaurs were able to adapt to better than other animals. The contents of the fossils became more varied over time, suggesting that larger dinosaurs with more diverse feeding habits began to gain prominence in the late Triassic period a little over 200 million years ago.

Evidence of oldest known alphabet unearthed among Syrian tomb treasures

Clay cylinders that are 4,400 years old, unearthed from a tomb in Syria, are inscribed with traces of the earliest known alphabetic writing system. The tomb, discovered in Umm el-Marra in 2004, contained four of these finger-sized cylinders, engraved with eight distinct symbols. Although the characters do not correspond to a known language, archaeologist Glenn Schwartz analysed the inscriptions and suggested that the symbols represent sounds that correspond to a, i, k, l, n, s and y. The inscriptions might record people’s names or label objects in the tomb, Schwartz says.

First rocks returned from Moon’s far side reveal ancient volcanic activity

Two groups of researchers have taken the first-ever look at samples brought back from the Moon’s far side — and revealed a history of volcanic activity that spans billions of years. Nearly two kilograms of lunar soil was retrieved by the China National Space Administration mission Chang’e-6 and then dropped down to Earth in a re-entry capsule. Scientists found grains of dust in the sample that originated from lava that erupted to the surface as long as 4.2 billion years ago.

Fossil sheds light on early bird brains

A remarkably well-preserved three-dimensional fossil has allowed researchers to digitally reconstruct the brain of an ancient bird species, the newly designated Navaornis hestiae. The starling-sized bird lived around 80 million years ago, a period from which 3D bird skulls have been difficult to find. The reconstruction gives researchers a glimpse of a stage of avian brain evolution between the earliest known birds and those alive today, partially filling in what was a knowledge gap of 70 million years.

First DNA from Pompeii body casts illuminates who victims were

Remains recovered from plaster casts of five people who died in the eruption of Mount Vesuvius have overturned some old assumptions about who they were. For example, a victim wearing an intricate golden bracelet had been described as a mother who died while holding their child. In fact, the adult was male and the two people were not related. Many of these narratives were designed to boost public interest in the site, notes archaeologist Steven Ellis. DNA evidence confirmed more scholarly interpretations, based on cultural artefacts, that Pompeii had a genetically diverse population descended from immigrants from the eastern Mediterranean.

Smashing atomic nuclei together reveals their elusive shapes

A new imaging method takes snapshots of atomic nuclei smashing together in high-energy collisions to help physicists better understand their shapes. Nuclei can take on a variety of forms, which can be tricky to predict: some are rigid and some fluctuate between several. The new method tracks the momentum of thousands of particles that result from collisions and matches the results with models to “roll back the clock to infer the shape of the nuclei”, says physicist Jiangyong Jia.

Cylinder symbols hint to origins of writing

Symbols engraved on cylinders that were used by traders to print motifs on clay tablets might have influenced the earliest-known form of writing. Researchers examined some of these cylinders from Mesopotamia, now southern Iraq, dating back to 4400 BC, around 1,000 years before the known invention of writing. They identified several symbols they think later developed into signs in ‘proto-cuneiform’, the precursor to the earliest version of written script. The findings support a theory first suggested in the 1990s by archaeologist Holly Pittman, but other experts caution that although some symbols on the cylinders might resemble those in proto-cuneiform, there is no obvious causal relationship linking them.

The world’s oldest tree? Genetic analysis traces evolution of iconic Pando forest

DNA from ‘Pando’ — a vast forest made up of a single root system sprouting nearly 50,000 cloned quaking aspen trees — seems to confirm that it is one of the oldest organisms on Earth. Researchers sequenced hundreds of samples from the Populus tremuloides and found that it is between 16,000 and 80,000 years old. They were also able to track patterns of genetic variation spread throughout the tree, offering clues about how it has adapted and evolved over the course of its lifetime.

Chemical swaps give parrots their colours

Dusky lory parrots (Pseudeos fuscata) have a unique genetic change that allows them to sport a rainbow of colours. Pigments in their feathers called psittacofulvins, which are only found in parrots, are made up of carbon chains of varying lengths. These chains have an aldehyde group at one end by default when they’re synthesised, which makes the pigment red. Researchers found a gene in the dusky lory’s genome that encodes an enzyme that can modify the aldehyde into a carboxyl group, which changes the pigment’s colour to yellow.

The ineffable quality of the human brain

Our brains allow us to do all sorts of things unique to humans: use sarcasm, solve crossword puzzles, envision our future. Their complexity also leaves us susceptible to conditions we don’t see in animals, such as bipolar disorder and schizophrenia. An avalanche of data has started to reveal key differences between human and animal brains, but exactly what gives rise to our unique cognitive skills still isn’t totally clear.

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From the perspective of Systemic Functional Linguistic Theory, the meaning potential of language is the 'elephant in the room' that gives rise to our unique cognitive skills. Semiotic phenomena require semiotic explanations. Material models of the brain are severely limited to explaining its material phenomena, such as the locations of its processes.

PhD student finds lost city in Mexico jungle by accident

An ancient Maya city has been found “hidden in plain sight” beneath the jungle canopy in the Mexican state of Campeche. Archaeologists used a laser technique called LiDAR to scan the area, “accidentally” discovering the forgotten complex, which contains pyramids, amphitheatres and sports fields. They think the site, which they’ve named Valeriana, might have housed up to 50,000 people, which supports claims that Maya lived in complex cities or towns, not in isolated villages.

Physicists tame fundamental muon particles into highly controlled beam for first time

Researchers have accelerated muons — the heavier, unstable cousins of electrons — into a tightly controlled beam for the first time. A team at the Japan Proton Accelerator Research Complex in Tokai shot a laser at a stream of muons to bring the fast-moving particles to a near-standstill. Then, the researchers applied an electric field to accelerate these ‘cooled’ muons to around 4% of the speed of light. The feat takes researchers a step closer to making a muon collider, which would be smaller and cheaper than other current colliders, a reality.

DNA stores data in bits after epigenetic upgrade

An epigenetic upgrade allows DNA to store information as a binary code — the strings of 0s and 1s used by standard computers. Researchers developed a system in which short, prefabricated DNA “bricks” — with or without methyl groups — could be added to a reaction tube to form a growing DNA strand that represented a desired binary code. The encoded information could then be read using a DNA-sequencing technique that detects the methyl groups along the strand.

Ancient meteorite was ‘giant fertiliser bomb’ for life

A meteorite up to 200 times bigger than the one that killed the dinosaurs might have acted as a “giant fertiliser bomb” that helped early microorganisms to thrive more than 3 billion years ago. The space rock would have caused a tsunami, partially evaporated the oceans and plunged Earth into darkness. On the plus side for Palæoarchæan life, it also released phosphorus and sloshed iron-rich water up from the deep.

Smallest fossilised dinosaur eggs ever found

Researchers in China have dug up the smallest known non-avian dinosaur egg at a construction site near the city of Ganzhou. At 29 millimetres long, the egg is about the size of a small strawberry. It was found in 2021 as part of a cluster of six eggs, and dated to be 80 million years old. Electron microscopy revealed that the eggs belonged to an unknown species, which the team named Minioolithus ganzhouensis.

AlphaFold reveals how sperm and egg hook up in intimate detail

Researchers have identified three proteins that work together as matchmakers between sperm and egg cells. They used the artificial-intelligence tool AlphaFold to predict the interactions between proteins of sperm cells. It predicted that three such proteins form a complex, which creates a place for an egg protein to bind.

Early galaxies are too big and too bright

Images from the James Webb Space Telescope are a portal to the past, allowing astrophysicists to study galaxies from the first billion years of the universe. These young galaxies appear bigger and brighter than our current theories about the evolution of the universe say they should be, leaving researchers to debate explanations for how these infant galaxies could have grown up so fast.

‘Stunning’ find in stone city of Petra

Geophysicists and archæologists have collaborated to discover an undisturbed burial site beneath the elaborate rock-cut Treasury building in Petra. After a non-invasive scan revealed temptingly tomb-like voids, digs confirmed the presence of 12 skeletal remains and a collection of grave artefacts. Researchers estimate that the remains might be from the height of the Nabataean society, which built the mountain fortress of Petra in what is now Jordan.

AI scans RNA ‘dark matter’ and uncovers 70,000 new viruses

A trawl of genomic samples archived in publicly available databases has revealed 70,500 RNA viruses that were previously unknown to science, many of them weird and nothing like known species. Researchers developed a deep-learning model to recognize the gene sequences that encode a key protein in the ubiquitous microorganisms. Looking at more than 10,000 samples from around the world, the team found new viruses in environments that included air, hot springs and hydrothermal vents.

Genome sequencing inside intact cells

A powerful new microscopy technique can simultaneously sequence an individual cell’s DNA and pinpoint the location of proteins inside it — all without having to break open the cell. Imaging DNA and proteins inside intact cells provides crucial information about how these molecules work together. The team behind the method, called expansion in situ genome sequencing, has already used it to study how ageing might alter the way that proteins in the nucleus interact with chromosomes.

Is this how complex life evolved?

With a tiny hollow needle and a bicycle pump, scientists have successfully kick-started an artificial endosymbiotic relationship by implanting bacteria into a fungus cell. These relationships, in which a microbial partner lives harmoniously within the cells of another organism, are thought to be what sparked the evolution of complex life. The systems could help researchers to understand how cell structures such as mitochondria and chloroplasts emerged more than a billion years ago. Researchers recreated a natural symbiosis by implanting the bacterium Mycetohabitans rhizoxinica into the fungi Rhizopus microsporus. When spores germinated, bacteria were also present in the cells of the next generation of fungi, showing that the endosymbiosis could be passed onto offspring.

This fish’s legs are made for walking — and tasting the sea floor

The northern sea robin (Prionotus carolinus) uses its six legs to stroll the ocean bottom and to taste the sea floor for buried prey. A detailed study of the unusual appendages has shed more light on how they help make the fish a spectacularly good hunter, and how P. carolinus repurposed its legs as sensory organs — as well as the evolutionary history of legs in the broader sea-robin family (Triglidae).

Carbon bond that uses only one electron seen for first time

Scientists have observed a single-electron covalent bond between two carbon atoms for the first time. Researchers synthesized a molecule with a stable ‘shell’ of fused carbon rings that stretched out a carbon–carbon bond in its centre. The pull makes it susceptible to losing one electron in an oxidation reaction, leaving the elusive one-electron bond. With the new finding, the team hopes to better understand what defines a chemical bond in the first place.

Bacteria can invert gene sequences

Bacteria have the capacity to flip sequences of their genes from back to front, which can generate two different proteins from a gene. For example, Bacteroides thetaiotaomicron has a gene, thiC, that it can invert. One way round, it encodes for an enzyme needed to make the vitamin thiamine. The other way, it encodes a truncated protein. This ability seems to give the bacteria a survival advantage in different conditions. Researchers engineered bacteria that were ‘locked’ to either express the forward or the inverted version of thiC and examined the survival of the two populations of bacteria when grown at different concentrations of thiamine. Under conditions of low thiamine, bacteria that expressed the forward version of thiC dominated; when thiamine was high, the bacteria that expressed the inverted version of thiC had an advantage.

Octopuses and fish caught on camera hunting as a team

Octopuses and fish have been caught on camera teaming up to hunt for prey. Researchers caught 13 instances of the cross-species collaboration over 120 hours of footage, showing a big blue octopus (Octopus cyanea) working with different fish species to capture meals. Each of these scenes hinted at complex group dynamics, with different species adopting different roles.

Mathematicians discover new class of shape seen throughout nature

Mathematicians have described a new class of shape — soft cells. These shapes have corners that are deformed into thin points with internal angles of zero, which let them tessellate on a 2D plane with no gaps. Soft cells are common in nature, from the inside of onions to mollusc shells, but this new work is the first time they’ve been formally described.

How cells swap instant messages

Cells in our bodies are passing delicate, time-sensitive notes to each other. These notes come in the form of messenger RNA (mRNA), which cells have to neatly package in sacs called vesicles to send between cells. This year, researchers showed that cells in all three domains of life - archaea, bacteria and eukaryotes - can send these messages, and even that they can be used as weapons between species. There are still questions to answer, such as whether other molecules packed into vesicles are necessary for mRNA’s message to land.

Entangled quarks seen for first time

For the first time, scientists have observed quantum entanglement — a state in which particles intermingle and can’t be described separately — in fundamental particles called top quarks. Physicists had no reason to suspect that quarks wouldn’t allow themselves to be entangled, but researchers say this measurement, achieved by analysing over 1 million pairs of quarks created in collisions between protons, could pave the way for future high-energy tests of the phenomenon.

The crustaceans that smell their way home

Tiny crustaceans called mysids (Hemimysis margalefi) can use ‘smell’ to find their way back from the open sea to the caves where they live. When placed in Y-shaped containers in which one arm contains seawater from their home cave, the shrimp-like creatures tended to opt for the water they were used to. Researchers showed that water from each cave had a unique chemical signature, which they suspect the mysids are using to find their way back in low-light conditions.

‘The standard model is not dead’: ultra-precise particle measurement thrills physicists

Researchers at CERN have calculated the mass of a fundamental particle called the W boson: 80,360.2 million electronvolts. The result quashes suggestions of a problem with the ‘standard model’ — physicists’ best description of particles and forces — raised by a discrepancy between the measured W boson mass and what the standard model predicts that was reported in 2022.

AlphaFold reveals how viruses evolved

Protein structures predicted by AI models have revealed some twists in the evolution of flaviviruses — a group that includes hepatitis C, dengue and Zika viruses. Researchers used DeepMind’s AlphaFold2 and Meta’s ESMFold to generate more than 33,000 predicted structures for proteins from 458 flavivirus species. They already uncovered some surprises. For example, the hepatitis C virus infects cells using an entry system similar to one seen in the pestiviruses — a group that includes animal pathogens like swine fever. Another big surprise was the discovery that some flaviviruses have an enzyme that seems to have been stolen from bacteria.

Rapa Nui’s population 'crash' debunked by ancient DNA

A study of ancient genomes has dispelled the theory that early inhabitants of Rapa Nui (also known as Easter Island) ravaged its ecosystem and caused the population to crash. Researchers analysed the DNA of ancient and modern Rapa Nui individuals and found no sign of a ‘population bottleneck’ that would have indicated a collapse. Genomes from ancient Rapa Nui people are predominantly of ancestries similar to those of other Pacific islanders, but around 10% of their genetic material can be traced to ancestors from coastal areas of what is now called South America. The findings suggest that Rapa Nui people made contact with people from these regions hundreds of years before Europeans first visited the island.

Marmosets use specific ‘names’ for one another

Marmosets use specific vocal labels to address other individual members of their species. When researchers separated pairs of marmosets with a barrier, they found that they used distinct ‘phee calls’ for the monkey on the other side. Besides humans, only dolphins and elephants have been recorded using similar labels for their fellow animals.

‘Nuclear clock’ breakthrough paves the way for super-precise timekeeping

Physicists have demonstrated all the ingredients of a nuclear clock — a device that keeps time by measuring tiny energy shifts inside an atomic nucleus. The breakthrough came from probing the nuclei of a rare isotope with a laser device called a frequency comb. Although the set-up isn’t technically a clock, because it hasn’t been used to measure time, “such impressive results make the development of a nuclear clock seem possible”, says atomic physicist Marianna Safronova. “It’s really one of the most exciting papers in recent times.”

The biology of smell is a mystery — AI is helping to solve it

We smell by detecting molecules around us — but knowing the chemical structure of a molecule tells you almost nothing about its odour. Even categorising what we perceive is difficult: there is no palette of scent ‘primary colours’ as there is for vision. And olfactory receptor proteins are hard to work with, so what they look like and how they function has mostly been guesswork. But that isn’t stopping scientists from trying, with help from innovations in structural biology, data analytics and artificial intelligence.

An asteroid might have flipped Ganymede

Four billion years ago, Jupiter’s moon Ganymede might have been permanently turned by an asteroid 20 times bigger than the one that killed the dinosaurs. Researchers analysed distinctive furrows on the moon’s surface that point almost directly away from the gas giant. The furrows could be the remnants of a crater formed by an asteroid that was around 300 kilometres wide, say scientists. The impact might have turned Ganymede’s face away from Jupiter and reoriented its former far side towards the planet.

Neolithic builders had an understanding of science

The Neolithic farmers and herders who built a massive stone chamber in southern Spain nearly 6,000 years ago seem to have possessed a good rudimentary grasp of physics, geometry, geology and architectural principles. Using data from a high-resolution laser scan, as well as unpublished photos and diagrams from earlier excavations, archæologists pieced together a probable construction process for the monument known as the Dolmen of Menga.

India’s pioneering mission bolsters idea that Moon’s surface was molten

The first-ever analysis of soil near the Moon’s south pole has found further evidence that the lunar surface melted shortly after it formed. The data come from India’s pioneering Chandrayaan-3 mission, which deployed a rover on the Moon last August that found the soil mainly comprised the mineral ferroan anorthosite. Previous landers have found similar results at other locations, suggesting the composition of the surface is uniform. This supports the theory that the Moon originated from material scattered into space when a large impactor struck the newly formed Earth.

Spider makes fireflies flash as bait

Orb-weaving spiders (Araneus ventricosus) make trapped male Absocondita terminalis fireflies flash like females to tempt more insects into their web. The spiders bite and wrap a flashing male firefly using a different technique than the one used on other prey. This method seems to change the repeating light sequence of the male firefly — which can still flash after being bitten — to one that resembles a female’s single pulse. The signal seems to tempt more males to their demise.

Primordial black holes are too scarce to explain dark matter

Primordial black holes (PBHs) would have to be at least ten times more abundant to support the theory that they make up a substantial proportion of the dark matter in our Galaxy. Researchers looked for black holes that formed during the early history of the Universe by observing stars in the Large Magellanic Cloud (LMC). A 20-year survey called the Optical Gravitational Lensing Experiment (OGLE) found 13 candidate signals. The detections involved an effect known as microlensing, in which a PBH (or other object) deflects and distorts the light from a star located farther away than the PBH, producing multiple magnified images of the star. The copies cannot be distinguished because they are too close to each other, but their combined brightness shows a characteristic increase as the PBH passes through the line of sight of the star (upper panel).

Dinosaur-killing Chicxulub asteroid formed in Solar System’s outer reaches

The asteroid that wiped out the dinosaurs was formed beyond the orbit of Jupiter. When the object struck what is now Chicxulub, Mexico 66 million years ago, the enormous explosion left a layer of asteroid material all over Earth. Researchers looked at an element preserved in that layer, ruthenium, and found that it matched the make-up of the type of asteroid that formed in the outer Solar System, rather than the type that was produced in the inner region.

Geology’s biggest mystery: when did plate tectonics start to reshape Earth?