Mediæval graves reveal secrets of the Avars

DNA has been extracted from ancient graves in four cemeteries in Hungary that were once at the heart of a mysterious nomadic culture. The Avars were nomadic people who migrated to eastern and central Europe from the late sixth century to the early ninth century. The researchers analysed genomes from 424 individuals using computational techniques to connect distant family members through their shared DNA, including a nine-generation family tree. The data suggest that the Avars kept aspects of their cultural heritage from the Asian steppes, such as very strict rules against inbreeding.

Bioluminescence evolved 540 million years ago

An ancient group of glowing corals pushes back the origin of bioluminescence in animals to more than half a billion years ago. Tiny crustaceans that lived around 270 million years ago were previously thought to be the earliest glowing animals. Genetic analysis and computer modelling revealed that octocorals probably evolved the ability to make light much earlier, around the time when the first animals developed eyes.

Fossil snake discovered in India may have been the largest ever

Fossil vertebrae of possibly the longest snake to have ever lived have been unearthed in a coal mine in India. Researchers recovered 27 vertebrae of a snake estimated to reach up to 15 metres in length, more than twice that of the longest snakes alive today, reticulated pythons (Malayopython reticulatus), and probably slightly longer than the extinct Titanoboa. The snake, dubbed Vasuki indicus, lived 47 million years ago.

Your perception of time is skewed by what you see

When people look at larger, less cluttered scenes — a big, empty warehouse, for example — they think they viewed it for longer than they actually did. Similarly, people experience time constriction when looking at more constrained, cluttered scenes, such as an image of a well-stocked cupboard. The study of 52 participants also showed that people are more likely to remember the images they thought they viewed for longer.

Physicists debate Universe-expansion data

Hopes that the James Webb Space Telescope (JWST) would finally settle the debate over how fast the Universe is expanding were dashed after two teams that used JWST data calculated different values. Observations of the current Universe typically find the expansion rate — the Hubble constant — to be about 9% faster than predictions based on early-Universe data.

Animal consciousness needs a rethink

A coalition of scientists has published a declaration that there is “a realistic possibility of conscious experience” in all vertebrates and in many invertebrates, such as octopuses and insects. The group focuses on sentience — an aspect of consciousness often defined as being able to have subjective experiences — pointing to research suggesting that octopuses feel pain and that bees show play behaviour.

The Secret to the Strongest Force in the Universe

Physicists are finally getting to grips with the mysterious strong force, which binds quarks into protons and neutrons and holds the nucleus together. The physicists who made the first measurements in the range of distances where the strong force becomes especially strong and difficult to calculate, and came up with theoretical predictions to match, describe their breakthrough. We at last have the ability to calculate aspects of quantum chromodynamics — the fiendishly complex theory that describes how the force works — from first principles

Hyperphantasia and the quest to understand vivid imaginations

Some people experience intense visual imagery, called hyperphantasia, that means they can replay memories or imagine scenes that are as vivid as real life. Once thought to be rare, research now suggests as many as 1 in 30 people have such vivid imaginations. At the other end of the spectrum are people with ‘aphantasia’, who have no visual imagery at all. Science is just catching up with this neurodiversity and how it influences memory, childhood, and even mental health.

Violent volcanoes shaped Jupiter’s moon

The most volcanically active place in the Solar System, Jupiter’s moon Io, has been shaped by volcanoes for billions of years. Lava and ash spewing from hundreds of volcanoes continuously resurface Io, obscuring any physical evidence of its history. Scientists now used sulphur in the moon’s atmosphere as “a tracer for studying Io’s long-term evolution”, explains planetary scientist and study co-author Katherine de Kleer. Because lava on Io is thought to be similar to magma on early Earth, “Io’s volcanism might be giving us a window into the mechanisms of volcanism and Earth’s early history”, she adds.

Goldene: a single layer of gold atoms

Goldene is a cousin of graphene, the single-atom-thick sheet of carbon first discovered in 2004 — but made of gold. Goldene is roughly 400 times as thin as the thinnest commercial gold leaf, and might find use as a catalyst, or in light-sensing devices.

Three new species of extinct giant kangaroos

Researchers have identified three new giant kangaroo species that lived around 5 million to 40,000 years ago. One of them, Protemnodon viator, weighed up to 170 kilograms — about twice as much as the largest living kangaroos. While most Protemnodon species were thought to move on four legs, viator had long limbs and could probably hop long distances.

Algae that can fix nitrogen

A new organelle that can turn atmospheric nitrogen into biologically useful molecules has been discovered in a marine alga. It’s the first time nitrogen fixation has been recorded in eukaryotes (the group of organisms that includes plants and animals). The discovery offers hope that crops could one day be engineered to grab nitrogen from the air — essentially making their own fertiliser.

First direct image of a Wigner crystal

A Wigner crystal — a structure made entirely of electrons — has been imaged directly for the first time. Until now, there had only been indirect evidence of the crystal, which forms at low temperatures. Using high-resolution scanning tunnelling microscopy, the team saw the electrons inside two thin graphene sheets arrange themselves into a triangular lattice, just like physicist Eugene Wigner predicted in 1934.

Ritual sacrifice across Stone Age Europe

Evidence from burial sites across Europe might point to a common ritual involving human sacrifice. Shared characteristics — such as the style of killing, broken grindstones, remnants of animal sacrifices and round, silo-like structures — suggest that these rituals might have been a widespread practice amongst cultures that were otherwise quite different.

Blackfoot people’s ancient ice age lineage

Modern Blackfoot people are closely related to the first humans that populated the Americas after the last ice age. DNA analysis of six modern and seven historic individuals shows that they belong to a previously undescribed genetic lineage that extends back to more than 18,000 years ago. The data add to evidence from Blackfoot oral traditions and archaeological findings, and could support the claims that these people have to ancestral lands.

First planet with a permanent dark side

Super-Earth LHS 3844b is the first exoplanet to show convincing signs of tidal synchronisation, meaning one of its hemispheres is permanently illuminated by its star and the other is in permanent darkness. The planet is relatively cool, indicating that it lacks the tidal heating non-locked planets experience. It’s unclear whether tidally locked planets could be habitable.