22,000-year-old tracks are earliest evidence of transport vehicles

Gently curving tracks preserved in New Mexico could be evidence of one of the earliest-known uses of transport technology: handcarts without wheels, called travois. The tracks were found alongside footprints that the same team earlier revealed could be around 22,000 years old — if so, they are the oldest evidence of human settlement in the Americas, setting the date thousands of years earlier than other timelines. Researchers built their own travois and dragged them through sand to reproduce a pattern that they say might indicate “adults pulled the simple, probably improvised travois, while a group of children tagged along to the side and behind”.

How AI is revealing the language of the birds

Researchers have been eavesdropping on unusually close-knit families of carrion crows (corvus corone corone) in Spain, collecting data on hundreds of thousands of different vocalisations. Small microphones recorded a variety of soft calls, far quieter than the familiar ‘caws’. The team then used AI to analyse and group the sounds. The researchers aim to better understand how the crows cooperate — and experiment with some human-crow chats.

Biggest-ever AI biology model writes DNA on demand

Scientists today released what they say is the biggest-ever artificial-intelligence (AI) model for biology. The model — which was trained on 128,000 genomes spanning the tree of life, from humans to single-celled bacteria and archaea — can write whole chromosomes and small genomes from scratch. It can also make sense of existing DNA, including hard-to-interpret ‘non-coding’ gene variants that are linked to disease.

‘Unconventional’ nickel superconductor excites physicists

Physicists have observed the key hallmarks of superconductivity in a thin film of crystals of nickel oxide, which they grew in the laboratory, at room pressure and a relatively high temperature of 45 kelvin (–228 °C). These crystals now join two groups of ceramics as ‘unconventional superconductors’ that can operate without being squeezed under pressure and at temperatures well above absolute zero. This new data point could be a step towards creating superconducting materials that work under ambient conditions, which would make technologies such as magnetic resonance imaging much cheaper and more efficient.

A human gene makes mice squeak differently — did it contribute to language?

The development of spoken language might have been influenced by a protein variant unique to humans. The NOVA1 protein, which is involved in brain development, differs between humans and animals by a single amino acid. To test the impact of such a small tweak, scientists used CRISPR gene-editing technology to replace the gene that expresses NOVA1 in mice with the version found in humans. The swap made the mice’s vocalisations more complex, which could suggest that the variant causes subtle brain changes that affect our ability to communicate.

Record-breaking neutrino is most energetic ever detected

Astrophysicists have observed the most energetic neutrino ever. The particle — which probably came from a distant galaxy — was spotted by the Cubic Kilometre Neutrino Telescope (KM3NeT) anchored to the floor of the Mediterranean Sea. KM3NeT picks up light emitted by high-energy, electrically charged particles such as muons — which can be produced when high-energy neutrinos smash into Earth’s atmosphere. In early 2023, it detected a muon that carried approximately 120 petaelectronvolts of energy. From the particle’s energy and its near-horizontal trajectory, researchers concluded that it was probably produced by a neutrino more than 20 times more energetic than any seen before.

Many birds-of-paradise species emit light through their plumage

Most species of birds-of-paradise are biofluorescent — parts of their body and their feathers can absorb UV or blue light and emit it back out at different frequencies — which makes their colours more vibrant. Of the 45 species, researchers found that 37 showed biofluorescence, with glowing body parts differing between males and females. Researchers theorise that the phenomenon would enhance courtship displays in males, whereas it seems more likely to be a camouflage aid in females.

Earth’s inner core is changing shape

By analysing how seismic waves from earthquakes travelled through the planet, scientists have found that Earth’s inner core is changing shape. They noted that the waveforms of some seismic signals changed between 2004 and 2008, and attributed the phenomenon to the inner core — normally thought to be solid and unyielding - bulging in some areas. Changes in the dynamics of the core could affect the Earth’s magnetic field and the length of our 24-hour day.

The origin of Indo-European languages

Ancient-genomics researchers have pinpointed the homelands of a nomadic tribe that transformed the culture and genetics of Europe and Asia, revealing a potential source for the Indo–European language family, spoken by nearly half of the world’s population. Genomes from more than 400 individuals suggest that the Yamnaya — Bronze Age herders from the grassy plains of present-day Russia and Ukraine — emerged along the northern shores of the Black Sea. “This Indo–European story has been a mystery for 200 years, and now step by step, we are coming closer to the solution,” says archaeologist Volker Heyd.

Why even physicists still don’t understand quantum theory 100 years on

Quantum physics works wonderfully, writes physicist and author Sean Carroll — but physicists don’t know why. “Or at least, if some of us think we know why, most others don’t agree.” On the centenary of quantum theory, Carroll delves into the counter-intuitive reality in which the act of observation influences what is observed — and few can agree on what that means.