Evidence of Europe’s first Homo sapiens found in French cave

Archæologists say they have found evidence that Homo sapiens lived briefly in a rock shelter in southern France — before mysteriously vanishing. New research suggests that distinctive stone tools and a lone child’s tooth were left by our species during a short stay some 54,000 years ago — and not by Neanderthals, who lived in the rock shelter for thousands of years before and after that time. The Homo sapiens occupation, which researchers estimate lasted for just a few decades, pre-dates the previous earliest known evidence of the species in Europe by around 10,000 years. But not everyone is convinced, and the tooth’s DNA has not been analysed to confirm its origins.

First glimpse of an isolated black hole

Astronomers have, for the first time, seen an isolated black hole, wandering unattached across the Milky Way. Lone black holes probably litter the Galaxy, but they’re extremely hard to spot because they are typically observed as they interact with other objects, such as companion stars. Confirming the black hole’s presence took ten years of observations, focusing on how the object’s extreme gravitational pull warps the light from distant stars behind it.

Direct evidence of two types of water

Water is unlike most other liquids on Earth: it has at least 66 weird properties, including high surface tension, high heat capacity, high melting and boiling points and low compressibility. Some chemists have come to think of it as not being one liquid at all, but two distinct liquid phases that coexist in a mixture. Now, physicists might have made the first direct observation of the transformation between the two states, in supercold water mixed with trehalose, a natural antifreeze that keeps the liquid from freezing.

How a disappearing ear bone turned bats into masters of echolocation

Some bats have an anatomical quirk in their ears that could explain how they evolved to hunt in specialized ways, from sensing small fish to catching insects midflight. In 2015, researchers took 3D images of the inner ear of a bat skull but couldn’t find a feature shared by almost all mammals: a bony tube that connects the ear to the brain and encases nerve cells. A more thorough search revealed many more bat species in which this bony nerve channel was missing or poked with large holes. Researchers suspect the loss of this bony channel gave the bats new hearing capabilities because the nerves are less confined.

New way to detect gravitational waves

Astronomers could be on the verge of detecting gravitational waves using rapidly spinning stars called pulsars for the first time. The waves could show up as tiny variations in the frequency of the radio signals emitted by the stars. The technique could allow astronomers to observe the ripples in space-time caused by distant supermassive black holes that are millions or even billions of times larger than those spotted so far. The International Pulsar Timing Array (IPTA) collaboration has not yet found conclusive evidence of these gravitational waves, but it has detected a background signal hinting that researchers are progressing in the right direction.

Everyday objects can run artificial intelligence programs

Physicists have built neural networks by combining objects instead of using silicon chips. They work by taking advantage of the inherent physical properties of mechanical systems — such as the vibration of a metal plate.

A Nitrogen-Fixing Seagrass Discovered

Seagrass (Posidonia oceanica) has formed a symbiotic relationship with a marine bacterium in order to acquire an essential nutrient: nitrogen. It’s a survival strategy that has never before been seen in an aquatic plant. The seagrass co-evolved with the newly described microbe, Celerinatantimonas neptuna, similarly to how legumes solved the same conundrum on land. The discovery explains how seagrass can form vast meadows in coastal environments around the globe — and helps us to understand the best places to restore degraded ecosystems.

Blogger Comments:

Evolutionary change does not happen 'in order to' (purpose) but 'because' (reason and result).

Did a mega drought topple empires 4,200 years ago?

In Mesopotamia in about 2200 BC, a mega drought lasted for decades or possibly even centuries. The drought might have contributed to the collapse of the Akkadian Empire, in what is now Syria and Iraq. But the drought’s extent is a matter of debate. Palæoclimatologists are working to pin down more details, which could hold clues to the kinds of natural droughts the world might face that could greatly exacerbate the impacts of climate change.

Ancient Crab Had Unusually Huge Eyes

A crab that paddled the ocean 95 million years ago had unusually keen vision thanks to its colossal bulbous eyes, according to a new study. The crab, Callichimaera perplexa, was only a few centimetres across but was probably a sharp-eyed predator.

Hippo talk: study sheds light on purpose of call and response

Hippopotamuses recognise the voices of their pod-mates and members of nearby pods, and respond more territorially to strangers, according to a study in Mozambique. Scientists recorded and broadcast hippo “wheeze honks”, which sound like deep, resonant grunts. Animals were more likely to respond aggressively by spraying larger amounts of dung when they heard strangers. This suggests that if a hippo needs to be relocated for conservation reasons, it might help to make the local hippos a sort of ‘mix tape’ of the new hippo’s voice for them to listen to in advance, and vice versa.

Earliest known human-made hybrid animal

A donkey-like animal that was highly prized by Mesopotamian elites might be the earliest known hybrid animal bred by humans. Researchers analysed the genome of these ‘kungas’, found buried alongside early Bronze Age royals in what is now Syria. The animals were the offspring of a female donkey (Equus africanus asinus) and a male Syrian wild ass (Equus hemionus hemippus), sometimes called a hemippe. The finding supports cuneiform texts that depict kungas as the product of complex animal husbandry programmes.

Vast Cosmic Bubble Around the Sun Identified as Source of Baby Stars

We live inside a vast, expanding bubble, a hollow in the matter and radiation that exist in the space between the stars. This ‘local bubble’ is driven by the expanding shock waves of 15 supernovas that have occurred over the past 14 million years. And nearly all the new stars and stellar nurseries within 500 light years of Earth lie on its surface.

Fossils Reveal When Animals Started Making Noise

The fossil record is revealing the first creatures that could hear and make noises. These include a 250-million-year-old insect that has the earliest known structures capable of producing sounds: drum-like membranes called tymbals, which can be contracted and relaxed to generate exceptionally loud clicks.

Huge ichthyosaur fossil found

A gigantic prehistoric “sea dragon” discovered in the Midlands has been described as one of the greatest finds in the history of British palæontology. The ichthyosaur, which is about 180m years old with a skeleton measuring about 10 metres in length and a skull weighing about a tonne, is the largest and most complete fossil of its kind ever found in the UK.

Stars may form 10 times faster than thought

A gas cloud could coalesce into a baby star ten times quicker than previously thought. Astronomers observed that the feeble magnetic fields outside the core of Lynds 1544, the beginnings of a star that’s forming in the Taurus Molecular Cloud, are even weaker than predicted. That gives gravity free rein in that region to crush enough gas together to spark nuclear fusion.

First millipede with more than 1,000 legs

Researchers in Australia have described the first reported millipede to live up to its name. The animal has 1,306 legs — breaking the previous record of 750 legs — and was found 60 metres underground in a mining area of Western Australia. It is pale and blind, with a long, thread-like body comprising up to 330 segments. Researchers named the species Eumillipes persephone, after the Greek goddess of the underworld, Persephone.

NASA spacecraft ‘touches’ the Sun for the first time ever

NASA’s Parker Solar Probe has travelled into the Sun’s corona — the first to have ever broached our star’s outer atmosphere. The Parker probe crossed the much-anticipated boundary, known as the Alfvén surface, on 28 April. It took several months for scientists to download the data and confirm the achievement.

Oldest domestic dog remains in Americas

A tooth found in caves in Haida Gwaii in Canada is the earliest reported remains of a domestic dog in the Americas. Radiocarbon dating pinpoints the tooth’s age to 13,100 years ago — the oldest archæological evidence of human occupation in the area by 2,000 years. The findings stand alongside oral histories that record the Haida people’s long history on the islands. Researchers predict more discoveries to come, because the caves on the west coast of Canada are mostly unexplored by archæologists.

DeepMind AI tackles one of chemistry’s most valuable techniques

The artificial-intelligence company DeepMind has developed a new machine-learning model to predict the density of a molecule’s electrons — a key step to calculating its physical properties. The algorithm relies on a technique called density functional theory (DFT), which has been hugely successful in chemistry, biology and materials science. But DFT goes a bit wonky in some cases, because it’s not a perfect reflection of the complex quantum mechanics that govern matter. Researchers trained an artificial neural network on data from hundreds of accurate solutions derived from quantum theory, plus some handy laws of physics.

Newly Found Dinosaur Had a Battle Axe for a Tail

Chilean researchers have discovered a new species of ankylosaur in the subantarctic tip of Chile. Stegouros elengassen was about 2 metres long, with a relatively large head, slender limbs and a flat, frond-shaped tail unlike any seen before.

Quantum Simulators Create a Totally New Phase of Matter

Physicists have created a physical simulation of an exotic and elusive state of matter first predicted in the 1970s, called a spin liquid. Spin liquids contain arrangements of electron spins — the subatomic equivalent of bar magnets — in a solid material that are intrinsically unstable, like the molecules in a liquid. Evidence for their existence is still preliminary, but researchers have now been able to simulate them using atoms suspended in a vacuum — a type of quantum computer that has received less attention than other technologies. Such ‘quantum simulations’ show promise as early applications of quantum computers.

This tiny iron-rich world is extraordinarily metal

Astronomers have spotted the tiniest, most metal-based planet yet — an iron-rich world that is 9 parsecs away from Earth and zips around its star once every 8 hours. The planet, known as GJ 367b, is three-quarters the size of Earth, but much denser. Its temperature reaches a searing 1,500 ℃ during the day — nearly hot enough for its iron to begin to melt.

DeepMind’s AI helps untangle the mathematics of knots

Artificial-intelligence (AI) powerhouse DeepMind has teamed up with mathematicians to spot previously unseen patterns and seek new discoveries. Researchers trained a machine-learning algorithm on vast amounts of data about knots and revealed a formula linking two properties of knots — which the mathematicians then proved rigorously. In a separate test, the team found a potential pattern related to symmetries, which had been sought for decades.

Earth’s eccentric orbit paced the evolution of marine phytoplankton

Variations in Earth’s orbit might help to determine the evolution of marine phytoplankton. Researchers analysed fossils of coccolithophores that lived in the Pleistocene period (from 2.6 million to 11,700 years ago) alongside deviations in the circularity of Earth’s annual orbit, which cycles approximately every 100,000 and 400,000 years. They found that the diversity of plankton species increased during periods of high eccentricity of Earth’s orbit, when the seasons vary more in equatorial regions.

A pair of nearby supermassive black holes are heading for a collision

A newly discovered pair of supermassive black holes is closer to Earth than any known so far. The two are only 1,600 light years apart, so astronomers predict they will smash together in a mere 250 million years. One sits at the centre of the galaxy NGC 7727, with the other just off to the side. Many more off-centre black holes could be hiding throughout the Universe, say astronomers — in which case, the cosmos might contain up to 30% more of the celestial objects than previously thought.

World's first living robots can now reproduce

The world’s first living robots, created from frog cells, self-replicate by pushing loose cells together. The Pac-Man-shaped blobs are made up of stem cells removed from frog embryos, which naturally cohere and develop hair-like protuberances called cilia. In a dish, they can move around and push loose stem cells into piles with their ‘mouths’. These piles can then develop into ciliated ‘offspring’, and go on to build their own pile-of-stem-cell babies.

Eurasia’s oldest surviving jewellery?

A 41,500-year-old pendant carved from a piece of a woolly mammoth tusk could be the oldest known example of decorated jewellery in Eurasia made by humans. The purpose and meaning of the designs on its surface are unclear, but they could represent a counting system, lunar observations or a way of scoring kills. The pendant was found in the Stajnia Cave, in Poland, alongside a 7-centimetre-long awl — a pointed tool used for making holes — shaped from a piece of horse bone.

Double-slit experiment performed with molecules

For the first time, scientists have used individual molecules to act as the slits in the iconic double-slit experiment that demonstrates quantum objects behaving as both particles and waves. Researchers created an ultracold molecular beam in which helium atoms collide with deuterium molecules. They used lasers to coax each deuterium molecule into a superimposed state of two different orientations, at right angles. The helium atoms scatter off the superimposed deuterium on two different paths that interfere with each other, showing the quantum interference effect that is characteristic of the classic double-slit experiment. Because the set-up is tuneable, it could be a step towards achieving ‘quantum control’ — which would harness quantum features to manipulate chemical reactions.

Homo naledi infant skull discovery suggests they buried their dead

The first partial skull of a Homo naledi child has been found in the remote depths of the Rising Star cave in South Africa. The bone fragments and teeth belong to a child that died almost 250,000 years ago, when it was approximately 4–6 years old. Palæoanthropologists have named the child Leti after the Setswana word letimela, meaning ‘the lost one’. The remains were found on a ledge in a tiny 20-by-80 centimetre passage — suggesting, that the skull was placed there deliberately, as a form of funerary practice.

Mammoth tusk recovered from deep sea

Scientists at the Monterey Bay Aquarium Research Institute made a surprising discovery while using a remotely operated vehicle (ROV) to explore the waters off California. Not only was it a mammoth tusk, it might be from an animal that died during the Lower Palæolithic era, from which well-preserved specimens are rare. The finding suggests that the ocean floor could be an as-yet-untapped source of palæontological treasures.

First quantum computer to pack 100 qubits

IBM’s newest quantum-computing chip packs in 127 quantum bits (qubits), making it the first such device to reach 3 digits. But the achievement is only one step in an aggressive agenda boosted by billions of dollars in investments across the industry. IBM and other companies — including the technology behemoths Google and Honeywell, and a slew of well-funded start-ups — ultimately aim to make quantum computers capable of performing certain tasks that are out of reach of even the largest supercomputers that use classical technology.

NASA spacecraft will slam into asteroid in first planetary-defence test

NASA will slam a multimillion-dollar spacecraft into an asteroid to test whether it is possible to change a space rock’s trajectory. This is only a test — the asteroid, Dimorphos, is not a threat to Earth. If the mission launches successfully next week, the Double Asteroid Redirection Test (DART) spacecraft will hit Dimorphos at 6.6 kilometres per second late next year. The impact should shrink Dimorphos’s orbit so that it orbits its companion asteroid at least 73 seconds faster than before — a change that will be detectable from Earth. A tiny probe funded by the Italian Space Agency will be launched from DART and will fly past to photograph the aftermath.

Electronegativity’s role in determining bond strengths needs to be rethought

Textbook knowledge about how to determine the strengths of chemical bonds seems to be oversimplified. Chemical bonds are usually stronger between atoms that have a larger difference in their electronegativity — which is influenced by the number of protons in the nucleus and the organisation of the electrons. But in some cases, researchers have found that differences in the sizes of the atom, rather than their electronegativity, determine the bond strength. The stability and length of chemical bonds are key factors in molecules’ structure and reactivity, so understanding them is important for developing everything from pharmaceuticals to materials.

Genes Reveal How Some Rockfish Live up to 200 Years

Some Pacific Ocean rockfishes can live for more than 200 years. Their secret to longevity: slowly growing large in the frigid depths. Researchers have found that the longest-lived rockfishes, a group that includes several species that can live for more than 105 years, have genes that indirectly affect lifespan by influencing size and adaptability. They also have more copies of genes linked to DNA maintenance and resisting the inflammation that often comes with age.

Diamond delivers long-sought mineral from the deep Earth

Small black specks in a diamond mined decades ago in Botswana have turned out to be a vital ingredient of the deep Earth. This is the first time the mineral has been identified in nature, after decades of searching.

Earth’s first continents emerged from the ocean 700m years earlier than thought

Earth’s first continents emerged from the ocean between 3.3 billion and 3.2 billion years ago, before the existence of plate tectonics. An analysis of rock sediments from India places the rise of the first stable continents some 700 million years earlier than previously thought. The rocks might have been formed by lava piling up from continuous volcanic activity on Earth’s crust, and floating above the water like an iceberg.

Astrophysicists unveil glut of gravitational-wave detections

Gravitational-wave observatories have released their latest catalogue of cosmic collisions, including one featuring the lightest neutron star ever detected in this way, as well as two clashes involving surprisingly large black holes. The detections come from the LIGO and Virgo observatories in the United States and Italy, respectively, which made the landmark first detection of gravitational waves in 2015.

Sponge cells hint at origins of nervous system

Sponges are expert filter feeders, straining tens of thousands of litres of water through their bodies every day to collect their food. And they do this without a brain, or a single neuron, to their name. Now, researchers have sequenced the RNA in various individual cells from a freshwater sponge (Spongilla lacustris) and found that sponges use an intricate cell communication system to regulate their feeding and to potentially weed out invading bacteria. The findings could help to understand how animals’ nervous systems evolved.

Honeybees use social distancing when mites threaten hives

Honey bees (Apis mellifera) change the way they interact with one another when infested with the mite Varroa destructor, a pathogen that can cause colony collapse. Researchers in Italy studied video recordings of the inside of hives and found that, in mite-infested hives, older members of the colony performed dances to direct other bees to food sources at the periphery, keeping them away from the centre — where young bees, the queen and brood cells are located. The researchers also observed more grooming activity, which can help to reduce the spread of parasites, at the centre of the infested hives.

Physicists fail to find mysterious 'sterile neutrino' particles

Researchers have, once again, failed to find any signs that hypothesised particles called sterile neutrinos exist. Neutrinos are some of the most abundant elementary particles in the Universe. There are three known types, but scientists have been searching for a fourth kind of neutrino for decades. If found, it could help to solve pressing problems in particle physics. Now, an experiment called MicroBooNE at the Fermi National Accelerator Laboratory did not turn up evidence of sterile neutrinos.

DNA reveals surprise ancestry of mysterious Chinese mummies

The genomes of 13 remarkably preserved 4,000-year-old mummies from China’s Tarim Basin suggest they weren’t migrants who brought technology from the West, as was previously supposed. Instead, the remains probably belong to Indigenous people who might have adopted agricultural methods from neighbouring groups. Researchers traced the ancestry of these early Chinese farmers to Stone Age hunter-gatherers who lived in Asia some 9,000 years ago.

Nearly 500 Mesoamerican monuments revealed by laser mapping — many for the first time

Scientists have uncovered nearly 500 ancient monuments in southern Mexico using an airborne laser mapping technology called lidar. Dating as far back as 3,000 years ago, the buried structures include huge artificial plateaus, built by the Olmec and Maya civilisations, that might have been used for ceremonial gatherings.

Signs of first planet found outside our galaxy

Astronomers have found hints of what could be the first planet ever discovered outside our galaxy. The possible planet, which is Saturn-sized, is in the Messier 51 galaxy, around 8 million parsecs away from the Milky Way. Nearly 5,000 planets orbiting stars beyond our Sun have been found so far, but all of these have been located within our galaxy.

Ancient DNA points to origins of modern domestic horses

Archæologists have used ancient DNA samples to identify the genetic homeland of modern horses, where the animals were first domesticated around 4,200 years ago. They found that modern domestic horses probably originated on the steppes around the Volga and Don rivers, now part of Russia, before spreading across Eurasia, ultimately replacing all pre-existing horse lineages.

Extinct Japanese wolf may hold clues to origins of dogs

The extinct Japanese wolf (Canis lupus hodophilax) might have come from a vanished population of grey wolves in east Asia that also gave rise to modern dogs. Researchers sequenced the genomes of nine specimens of the species (the last one was killed in 1905) to find where it sits on the canine evolutionary tree. The results, which have not yet been peer reviewed, show the Japanese wolf to be more closely related to the ancestor of dogs than are any other wolves found so far.

Physicists make most precise measurement ever of neutron’s lifetime

Physicists have measured the lifetime of the neutron more precisely than ever before. The average time it takes for the subatomic particle to decay is 877.75 seconds, according to an experiment that used magnetic fields to trap ultra-cold neutrons. The results have twice the precision of similar measurements, and are consistent with theoretical calculations. But they do not explain why neutrons live nearly 10 seconds longer in a different experiment that involves watching the particles decay as they move in a beam.

Blogger Comments:

The discrepancy might be explained by special relativity, according to which "clocks tick relatively more slowly" (time expands) for neutrons travelling in a beam.

First mission to the Trojan asteroids

The first spacecraft to journey to the Trojan asteroids, which share Jupiter’s orbit around the Sun, is set to lift off on 16 October. NASA’s Lucy mission — named after the iconic hominid fossil — will spend the next 12 years performing gravitational gymnastics to swoop past six of the asteroids. The Trojans probably formed when the planets were just coalescing, so exploring them can reveal more about the birth of the Solar System.

Evidence for tobacco use going back to the Pleistocene

Hunter-gatherers in North America might have been using tobacco around 12,300 years ago — 9,000 years earlier than was previously documented. Archaeologists found four burnt tobacco-plant seeds in an ancient hearth excavated in Utah. The seeds themselves were too small and fragile to be dated, but other burned woody material in the hearth is around 12,300 years old.

Jupiter’s Great Red Spot is swirling faster

The winds spinning around the outer edge of Jupiter’s striking Great Red Spot are speeding up, according to long-term observations by the Hubble telescope. Observations over the past century have already revealed that the storm is mysteriously shrinking. Hubble data collected between 2009 and 2020 add a new twist. Compared with a decade ago, when wind speeds in the Great Red Spot’s outer ring were typically just above 90 metres per second, they now exceed 100 metres per second.

First image of a solid made of electrons

If the conditions are just right, some of the electrons inside a material will arrange themselves into a tidy honeycomb pattern — like a solid within a solid. Physicists have now for the first time directly imaged these ‘Wigner crystals’, named after theorist Eugene Wigner. Researchers built a device containing atom-thin layers of two semiconductors and cooled it to just a few degrees above absolute zero. This slowed the electrons between the two layers enough so that they formed the elusive material.