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<![CDATA[ Latest from Live Science ]]>
https://www.livescience.com
- Sat, 01 Nov 2025 15:00:00 +0000
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+ <![CDATA[ First of its kind 'butt drag fossil' discovered in South Africa — and it was left by a fuzzy elephant relative 126,000 years ago ]]>
+ Rock hyraxes, known in southern Africa more often as "dassies," are furry, thickset creatures with short legs and no discernible tails. They spend much of their time sunning themselves on rocky outcrops.
Another thing they sometimes do is drag their butts along the ground. Dog owners know that this behavior can be a sign of parasitic infections; in hyraxes the reason seems to be less clear, but this action leaves distinctive traces in sandy areas.
Traces and tracks — ancient, fossilized ones — are what we study at the African Centre for Coastal Palaeoscience through the Cape south coast ichnology project. Over the past few decades, we have found almost 400 vertebrate tracksites on this coast, some as old as 400,000 years, in cemented dunes known as aeolianites from the Pleistocene epoch. This epoch lasted from about 2.58 million years ago to about 11,700 years ago.
We're building up a picture of the environment during that period and how the animals and plants of that time lived.
Among our latest finds are two fossilized traces that appear to have been made by rock hyraxes long ago. One is a track site and the other is a butt-drag impression with what may be a fossilized dropping in it.
The probable track site was brought to our attention from a site near Walker Bay on the Cape south coast by an ardent tracker, Mike Fabricius. It is around 76,000 years old. We found the probable butt-drag impression east of Still Bay on the same coast, and it is most likely around 126,000 years old.
The butt-drag impression is the first fossil of its kind to be described from anywhere in the world. In addition, these are the only possible fossilized hyrax tracks ever to be identified. In the world of paleontology, anything this unusual is important and we feel privileged to be able to interpret them.
A rock hyrax urinating beside a collection of droppings. These animals are the closest living relatives of elephants. (Image credit: Mathilde Stuart)
Interpreting the drag mark
Dating on our sites has been done through a technique known as optically stimulated luminescence, which works by analyzing when materials like sand were last exposed to light.
3D photogrammetry model of the probable hyrax butt-drag trace; the feature to the right of centre is interpreted as a probable coprolite. (Image credit: Charles Helm)
The butt-drag impression is 95 cm [37.4 inches] long and 13 cm [5.1 inches] wide. It contains five parallel striations. Its outer margins are slightly raised, and within it there is a 2 cm-high [0.8 inch] raised feature, 10 cm by 9 cm [4 by 3.5 inches]. Clearly something was dragged across the surface when it consisted of loose sand.
We considered possible causes other than hyrax buttocks. These included a leopard or an ancestral human dragging prey, or perhaps an elephant dragging its trunk. Firstly, however, these would be expected to leave tracks, and secondly in such interpretations the raised feature could not be explained.
But if it was a hyrax, it would make sense, because the buttock trace would have come after the tracks and wiped them out. And the raised feature might be a coprolite: a fused fossilized mass of hyrax droppings.
Old dung and urine
Rock hyraxes leave much more than just tracks and butt-drag traces. Because they prefer rocky areas, their tracks are not often found, but they polish rock surfaces to a shiny finish. This is similar to what buffalo on the North American prairie do, creating "buffalo rubbing stones".
A hyrax positioned above a few droppings and an accumulation of urolite, formed from cemented urine. It can be regarded as a trace fossil. (Image credit: Mathilde Stuart)
Hyraxes also leave deposits of urine and dung. Urea and electrolytes are concentrated in their urine, and they excrete large amounts of calcium carbonate. This becomes cemented and forms extensive whitish deposits on rock surfaces. Due to their communal habits, hyraxes often urinate in the same preferred localities over multiple generations.
Their urine and dung often mix to form a substance known as hyraceum — a rock-like mass that can accumulate into extensive, dark, tarry deposits. Hyraceum has been used as a traditional medication to treat a variety of ailments, including epilepsy, and for gynecological purposes.
Hyraceum may be tens of thousands of years old, and can be regarded as a threatened, non-renewable resource. The middens, being sensitive to environmental changes and containing fossil pollen and other evidence of ancient life, form valuable natural archives for interpreting past climates, vegetation and ecology.
Thinking of hyraceum as a trace fossil, something which apparently has not been done before, can help in the protection of this underappreciated resource.
Hyrax dropping have stained these rocks. (Image credit: Mathilde Stuart)
Although fossilized urine is globally uncommon, there is a word to describe it: "urolite", to distinguish it from "coprolite" (fossilized poop). It seems that hyraxes contribute the lion's share of the world's urolite. At paleontology conferences, students can be seen sporting T-shirts that brazenly state: "coprolite happens". In southern Africa, a more appropriate term might be "urolite happens".
Through appreciating the importance of butt-drag impressions, urolites, coprolites and hyraceum, and learning about the environment of rock hyraxes and other animals during the Pleistocene, we will never view these endearing creatures in the same light again.
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+ https://www.livescience.com/planet-earth/fossils/first-of-its-kind-butt-drag-fossil-discovered-in-south-africa-and-it-was-left-by-a-fuzzy-elephant-relative-126-000-years-ago
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+ Sun, 02 Nov 2025 15:00:00 +0000
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+ <![CDATA[ French archaeologists uncover 'vast Roman burial area' with cremation graves 'fed' by liquid offerings ]]>
+ Archaeologists excavating in the French Riviera have uncovered a massive Roman cremation cemetery. Careful work at the site has revealed the step-by-step process the Romans used to cremate their dead and honor them in the afterlife.
More than 160 cremation graves were discovered at the ancient site of Olbia, which began as a fortified Greek settlement around 350 B.C. in what is now the south of France. The geographer Strabo mentioned Olbia was a city of the Massiliotes — the people of nearby Massilia (modern-day Marseille). When Marseille was captured by Julius Caesar in 49 B.C., Olbia became a Roman city focused on trading and thermal baths.
All of the cremation graves date to Olbia's Roman period, between the first and third centuries A.D., and show the different ways people at the time dealt with their dead, according to a translated Oct. 29 statement from Inrap (the French National Institute for Preventative Archaeological Research).
For many of the deceased, the cremation process began when relatives put the dead body on a wooden stand built over a square pit. The heat of the pyre caused the stand to collapse and the bones to whiten, twist and crack, according to Inrap. Glass objects melted, bronze artifacts warped, and the ceramics were tinged by soot.
"A distinctive feature at Olbia is that most of [the graves] are surrounded by a libation channel for liquid offerings (wine, beer, mead) to honor the deceased or ensure their protection," according to the statement.
Two libation tubes that were found at Olbia in France. (Image credit: Tassadit Abdelli / Inrap)
These libation tubes were made from repurposed amphorae that stuck out of the grave, even after it was covered with roof tiles and filled in with dirt. The tubes allowed families to visit their loved ones and symbolically feed them on Roman feast days for the dead, such as the Feralia (Feb. 21) and the Lemuralia (May 9, 11 and 13).
At Olbia, some of the cremation pyres were turned directly into burial sites, while others were partially or fully emptied. But while the typical Roman custom was to collect bones in glass, ceramic or stone urns before burying them, at Olbia, many of the bones were piled in small heaps or placed in a perishable container, which may suggest social or cultural differences within the city's population, according to Inrap.
"These discoveries remind us that ancient funerary rites were rich, varied, and imbued with multiple meanings, some of which remain mysterious even today," Inrap representatives said in the statement.
Roman emperor quiz: Test your knowledge on the rulers of the ancient empire
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+ https://www.livescience.com/archaeology/romans/french-archaeologists-uncover-vast-roman-burial-area-with-cremation-graves-fed-by-liquid-offerings
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+ Sun, 02 Nov 2025 14:00:00 +0000
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+ <![CDATA[ On Saturn's largest moon, water and oil would mix — opening the door to exotic chemistry in our solar system ]]>
+ The frigid conditions on the surface of Saturn's largest moon, Titan, allow simple molecules in its atmosphere to break one of the most fundamental rules in chemistry, a new study shows.
According to this principle, known as "like dissolves like," mixtures containing both polar and nonpolar components, such as oil and water, usually don't mix and instead form separate layers.
But scientists from NASA's Jet Propulsion Laboratory and the Chalmers University of Technology in Sweden were surprised to discover that the polar molecule hydrogen cyanide forms stable co-crystals with the extremely nonpolar hydrocarbons methane and ethane on Titan's frigid surface — molecules that are normally entirely incompatible on Earth.
"This contradicts a rule in chemistry, 'like dissolves like,' which basically means that it should not be possible to combine these polar and nonpolar substances," lead study authorMartin Rahm, an associate professor of chemistry, biochemistry and chemical engineering at the Chalmers University of Technology, said in a statement.
The new study, published July 23 in the journalPNAS, challenges a long-held pillar of chemistry and could open the door to the discovery of more exotic solid structures across the solar system.
Re-creating Titan's surface
Conditions on Titan's surface bear a striking resemblance to those of early Earth, research suggests. Its atmosphere contains high levels of nitrogen and the simple hydrocarbon compounds methane and ethane, which cycle in a localized weather system, much like Earth's water cycle.
However, until now, researchers were unsure about the fate of the hydrogen cyanide produced by reactions in this atmosphere. Is it deposited on the surface as a solid? Does it react with its surroundings? Or could it be converted into the first molecules of life?
To investigate these questions, the NASA team replicated the conditions on Titan's surface by combining mixtures of methane, ethane and hydrogen cyanide at temperatures of around minus 297 degrees Fahrenheit (minus 183 degrees Celsius). A spectroscopic analysis — a way of studying chemicals through their interactions with different wavelengths of light — yielded unexpected results, suggesting that these contrasting compounds were interacting much more closely than had ever been observed before.
It appeared that molecules of nonpolar methane and ethane had slotted into gaps in the solid crystal structure of the hydrogen cyanide — a process known as intercalation — to create an unusual co-crystal containing both sets of molecules.
Ordinarily, polar and nonpolar molecules don't mix. Polar compounds, such as water and hydrogen cyanide, have an uneven distribution of charge across the molecule, creating some areas that are slightly positive and others that are slightly negative. These oppositely charged regions are attracted to each other, forming strong intermolecular interactions between the different polar molecules and largely ignoring any nonpolar components.
A view of Titan’s surface taken by the Cassini-Huygens probe in 2004. (Image credit: NASA/JPL/University of Arizona)
Meanwhile, nonpolar oils and hydrocarbons have an entirely symmetrical arrangement of charge and interact very weakly with neighboring nonpolar molecules and not at all with polar particles. As a result, mixtures containing both polar and nonpolar components, such as oil and water, usually form distinct layers.
To explain their bizarre observations, the NASA team joined forces with researchers at the Chalmers University of Technology to model hundreds of potential co-crystal structures, assessing each for its probable stability under the conditions on Titan.
"Our calculations predicted not only that the unexpected mixtures are stable under Titan's conditions but also spectra of light that coincide well with NASA's measurements," Rahm explained.
Their theoretical analysis identified several possible stable crystal forms, which they propose are stabilized by a surprising boost in the strength of the intermolecular forces in the hydrogen cyanide solid triggered by this mixing.
Their rigorous combination of theory and experiment impressed Athena Coustenis, a planetary scientistat the Paris-Meudon Observatory in France. She is excited to see how future data, including that from NASA's Dragonfly probe (due to arrive on Titan in 2034), will complement the study's findings.
"Comparing laboratory spectra with upcoming Dragonfly mission data may reveal signatures of these solids on Titan's surface, providing insight into their geological roles and potential importance as low-temperature, prebiotic reaction environments," Coustenis told Live Science in an email. Further work could even expand this approach to other molecules likely generated by Titan’s atmosphere, including cyanoacetylene (HC3N), acetylene (C2H2), hydrogen isocyanide (HNC), and nitrogen (N2), she said. “[This] will test whether such mixing is a general feature of Titan's organic chemistry."
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+ https://www.livescience.com/space/planets/on-saturns-largest-moon-water-and-oil-would-mix-opening-the-door-to-exotic-chemistry-in-our-solar-system
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+ Sun, 02 Nov 2025 13:00:00 +0000
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+ <![CDATA[ 5,000-year old 'cultic space' discovered in Iraq dates to time of the world's first cities ]]>
+ Archaeologists in Iraq have unearthed the remains of a 5,000-year-old building that may have been a temple from the Uruk period, when the first cities in the world were taking off.
The buried "monumental" structure was discovered in September at the Kani Shaie archaeological site in the northern Sulaymaniyah Governorate, in the foothills of the Zagros Mountains in northern Iraq, according toa statement.
"If the monumental nature of this building is confirmed — which we are now investigating in detail — the discovery could transform our understanding of Uruk's relationship with surrounding regions," the researchers said in the statement.
The structure dates from between about 3300 to 3100 B.C. during the Uruk period, which is named after Uruk in southern Mesopotamia.
Ancient Uruk was a city of up to 80,000 people, spread out over an area of up to 990 acres (400 hectares) with a grid-like pattern of streets and zones for different functions, such as administrative and residential neighborhoods, according the late German archaeologistHans Nissen in his key work "The Early History of the Ancient Near East" (University of Chicago Press, 1988).
The excavation leaders said in the statement that the structure was found in the top part of a mound of earth at Kani Shaie, and that its architectural style indicated it had been an official building of some sort and possibly a "cultic space" or temple for worship.
Image 1 of 2
(Image credit: University of Coimbra)
Among other artifacts, the latest excavations at Kani Shaie unearthed ancient "cylinder seals" associated with administration.
Image 2 of 2
(Image credit: University of Coimbra)
Archaeologists say the discovery shows the Kani Shaie settlement was integrated with a cultural network centered on the ancient city of Uruk in southern Mesopotamia.
Cylinder seal
The researchers also found fragments of a gold pendant, which may reflect a "social display" of wealth in the community; and "cylinder seals" from the Uruk period, which were associated with administration and political power, the statement said.
In addition, the team discovered ancient "wall cones" — decorative ornaments consisting of cones of baked clay or stone that were pressed point-first into fresh plaster on a wall. The flat parts of the cones were then painted, creating a mosaic effect across the wall that often featured geometric designs, such as triangles and zigzags. The wall cones are further evidence that the building was a "public or ceremonial structure," the statement said.
Kani Shaie was almost 300 miles (480 kilometers) north of Uruk, which would have been about 15 days' walk on foot. But the new finds suggest that it was not a peripheral place during the Uruk period, as archaeologists had previously assumed because of its distance. Instead, the settlement seems to have been part of an expansive cultural and political network that stretched across ancient Mesopotamia.
"Kani Shaie is regarded as the most important archaeological site east of the Tigris River for understanding the sequence of human occupation from the Early Bronze Age through to the 3rd millennium BC," the researchers said.
Image 1 of 2
(Image credit: University of Coimbra)
Archeologists have worked at Kani Shaie in the foothills of the Zagros Mountains since 2013.
Image 2 of 2
(Image credit: University of Coimbra)
The building may have been a "cultic space" or temple for worship, according to the researchers.
Ancient Uruk
Archaeologists have carried out excavations at the site since 2013 and found evidence of occupation since the Chalcolithic period (the "Copper-stone" Age) from about 6500 B.C. in this region until about 2500 B.C.
Uruk (modern Warka in southern Iraq) may have been the first city in the world and it strongly influenced the Sumerians and later Mesopotamian civilizations. The people of Uruk are credited with inventing cuneiform writing, which may have been the first writing system and was used throughout Mesopotamia for thousands of years. They are also credited with developing the first written numbers, which seem to have been used for tallies of farming produce.
Uruk also pioneered a form of the "ziggurat" style of building that would be used for temples by later Mesopotamian civilizations; and it may have been the first place where priests were distinguished with special vestments and religious iconography.
Mesopotamia quiz: Test your knowledge about the ancient civilizations of the Fertile Crescent
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+ https://www.livescience.com/archaeology/5-000-year-old-cultic-space-discovered-in-iraq-dates-to-time-of-the-worlds-first-cities
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+ Sun, 02 Nov 2025 12:00:00 +0000
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+ <![CDATA[ Webb reveals a fiery starburst in the Cigar Galaxy — Space photo of the week ]]>
+
Quick facts
What it is: M82, an edge-on spiral starburst galaxy
Where it is: 12 million light-years away in the constellation Ursa Major
When it was shared: Oct. 23, 2025
If you own a small backyard telescope, there's a good chance you've seen the Cigar Galaxy (M82) with your own eyes. Not only is it relatively close to the Milky Way and one of the brightest galaxies in the night sky, but it's visible beside Bode's Galaxy (M81). A spiral galaxy about four times smaller than the Milky Way, M82 shines five times more brightly and forms stars at 10 times the rate, earning it the title of a starburst galaxy.
This image from the James Web Space Telescope (JWST) reveals a glowing core teeming with billions of stars. The shot is a follow-up to a close-up image published in 2024. Despite being a side-on view of M82, the photo shows its brilliant core exuding a blue-white glare, with red and orange dust clouds being pushed out above and below. The gas clouds contain cavities and ridges — details that are only possible to spot because of JWST's Near-InfraRed Camera (NIRCam), which can see straight through them.
M82's core is a busy place, containing more than 100 super star clusters, some still being born within dense gas clouds. Each super star cluster hosts hundreds of thousands of stars. The reason for M82's burst of star formation is probably its neighbor, M81, whose gravity it has likely interacted with. As a result, gas from M81 has found its way into M82's center, spurring an uptick in star formation despite the galaxy's small size.
Scientists can also see the glow from plumes of organic molecules in this image. The broad plumes, which are 160 light-years across, are called polycyclic aromatic hydrocarbons (PAHs) and are being pushed away from the galactic disk by powerful outflowing winds produced by M82's super star clusters.
For stargazers in the Northern Hemisphere, M81 and M82 are a spectacular sight in the northern sky during fall and winter. Both galaxies can be spotted as small, diffuse patches of light northwest of Dubhe — the bright star marking the lip of the Big Dipper's bowl. Through a small backyard telescope, these two galaxies next door appear together in the same field of view.
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+ https://www.livescience.com/space/astronomy/webb-reveals-a-fiery-starburst-in-the-cigar-galaxy-space-photo-of-the-week
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+ Sun, 02 Nov 2025 11:00:00 +0000
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+ <![CDATA[ The Bering Land Bridge has been submerged since the last ice age. Will scientists ever study it? ]]>
+ The Bering Strait is a 52-mile-wide (85 kilometers), 165-foot-deep (50 meters) stretch of water between Alaska and Siberia. Today, it divides North America and Asia. However, during the coldest part of the last ice age between about 26,500 and 19,000 years ago, as the planet's water became frozen in massive ice sheets, global sea levels were about 425 feet (130 m) lower. The resulting Bering Land Bridge let animals such as mammoths and horses roam between Asia and the Americas.
Much remains debated about whether and how humans used the Bering Land Bridge to migrate to the New World. For instance, a 2022 study found that this strip of land may have been blocked by an icy barrier by the time humans could have come to it. As such, the first people in the Americas may have boated or walked along the bridge's coast instead of trekking across its interior on foot.
Given the potential to shed light on early human migrations, will archaeologists ever study the drowned land that was once the Bering Land Bridge? And what might they find there?
Exploring the buried Bering Land Bridge would be exceedingly difficult and costly, but the archaeological payoff could be extraordinary, experts told Live Science.
What ice age artifacts would we find?
Ideally, scientists would dig into the Bering seafloor to find signs of ancient human migrants.
"We have only a handful of archaeological sites in this area from the end of the ice age, so literally any site we find could completely change what we know about these early people," Jessi Halligan, an underwater archaeologist at Texas A&M University, told Live Science.
The chances are high that human sites and human remains could survive after millennia underwater. Because of the cold water of the Bering Strait, "any animals, clothing fragments, housing bits, charcoal, or other organic remains the people left behind are much more likely to have preserved because the cold water has fewer microbes to destroy them than can be found in open air or warmer water," Halligan said. "These sites could potentially be almost pristine."
However, actually making such discoveries in the Bering Strait "is a monumental challenge," Morgan Smith, director of the geoarchaeology and submerged landscapes lab at the University of Tennessee, Chattanooga, told Live Science. "The conditions there can become super-unmanageable super-fast."
The challenges of a Bering Strait excavation
To start with, the Bering Strait's frigid climate makes research there challenging. Ice is an obstacle for a significant chunk of the year, and the cold water there can prove a miserable experience for divers wishing to swim in it, Halligan said. Smith added that the area can experience fast currents, potentially making underwater work difficult.
In addition, "to give you an idea of the problems the weather poses, the Discovery Channel show 'The Deadliest Catch' takes place in the Bering Sea," Jesse Farmer, a paleoceanographer at the University of Massachusetts Boston, told Live Science. "The shallow seas there can get really rough very quickly when there's a storm. It's an extremely variable place in terms of weather — you need to get lucky with the conditions you face."
Moreover, there is the challenge all underwater archaeology faces: the water, Halligan noted.
"It is absolutely possible to send divers down to swim around and look for artifacts," Halligan said. However, this only works "when the seafloor is not covered by a bunch of marine sand that would have buried any traces of former landscapes and sites." This makes discovering potentially interesting sites through visual inspection essentially impossible.
Furthermore, "divers can only safely dive to about a max of 130 feet [40 m] deep," Halligan said. "At that depth, they can only be down a few minutes, so it is not a practical solution to cover very much of the seafloor."
A map of how Beringia — which includes the famous ice age land bridge — possibly looked about 18,000 years ago. (Image credit: Bond, J.D. 2019. Paleodrainage map of Beringia. Yukon Geological Survey, Open File 2019-2)
Farmer noted that at least 10 to 50 feet (3 to 15 m) of sediment would have settled on the seafloor in the past 10,000 to 11,000 years. "You can't just look around with a submersible if you don't know where to look," Farmer said. Smith noted that "it's a real needle-in-a-haystack problem."
When it comes to archaeology on land, researchers often dig small pits about 12 to 20 inches (30 to 50 cm) wide in promising areas to look for archaeological evidence.
"There is no equivalent to shovel test pits underwater," Halligan said. "Our closest attempt is taking cores, which are tubes or pipes forced vertically through the layers of the seafloor. These are usually 10 centimeters [4 inches] in diameter, and usually no more than a few dozen can be obtained from an area due to the time and cost investment."
Given such a large stretch of land to cover, attempting to find ancient sites with a few cores at a time might prove extraordinarily difficult.
"You can always get lucky — many amazing scientific discoveries have been made by sheer luck," Farmer said. "But luck doesn't get you funding."
The remote location of the Bering Strait also makes expeditions there expensive. "You need huge research vessels to go there, and those can cost $8,000 to $15,000 a day, not including fuel," Smith said. "These are really busy boats, so you have to reserve them a year in advance; you can't predict weather even 10 days in advance, so you have to hope that you don't have bad luck during your trip."
Currently, to find drowned sites, researchers first look for signs that details of the former landscape might actually have been preserved. This involves sonar, which uses sound waves to reveal objects or topography below, to peer at these former landscapes under sediment.
"It gives us a place to send divers down and/or take cores to look for artifacts or the traces of human activity — like, for instance, bacteria associated with humans and not other animals," Halligan said. "Cores that have already been extracted from the area have contained insect and pollen remains that have really helped us refine our understanding of past environments in the area."
Scientists have made some forays into exploring the Bering seafloor, "mostly done by researchers who have gotten funding from NOAA and Parks Canada," Halligan said. "Oil companies probably have done remote sensing surveys of much of the area. But they are not required to make their data public, so it is not available to archaeologists for the most part."
All in all, Bering seafloor research would "take time and money, but the outcomes could be extremely exciting," Halligan said. "There are almost certainly sites out there."
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+ https://www.livescience.com/archaeology/the-bering-land-bridge-has-been-submerged-since-the-last-ice-age-will-scientists-ever-study-it
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+ Sun, 02 Nov 2025 10:00:00 +0000
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+ <![CDATA[ We sharpened the James Webb telescope's vision from a million miles away. Here's how. ]]>After Christmas dinner in 2021, our family was glued to the television, watching the nail-biting launch of NASA's $10 billion James Webb Space Telescope. There had not been such a leap forward in telescope technology since Hubble was launched in 1990.
Six months later, Webb's first images were revealed, of the most distant galaxies yet seen. However, for our team in Australia, the work was only beginning.
We would be using Webb's highest-resolution mode, called the aperture masking interferometer or AMI for short. It's a tiny piece of precisely machined metal that slots into one of the telescope's cameras, enhancing its resolution.
Our results on painstakingly testing and enhancing AMI are now released on the open-access archive arXiv in a pairof papers. We can finally present its first successful observations of stars, planets, moons and even black hole jets.
Working with an instrument a million miles away
Hubble started its life seeing out of focus — its mirror had been ground precisely, but incorrectly. By looking at known stars and comparing the ideal and measured images (exactly like what optometrists do), it was possible to figure out a "prescription" for this optical error and design a lens to compensate.
The primary mirror of the Webb telescope consists of 18 precisely ground hexagonal segments. (Image credit: NASA/Chris Gunn)
By contrast, Webb is roughly 1 million miles (1.5 million km) away — we can't visit and service it, and need to be able to fix issues without changing any hardware.
This is where AMI comes in. This is the only Australian hardware on board, designed by astronomer Peter Tuthill.
It was put on Webb to diagnose and measure any blur in its images. Even nanometers of distortion in Webb's 18 hexagonal primary mirrors and many internal surfaces will blur the images enough to hinder the study of planets or black holes, where sensitivity and resolution are key.
AMI filters the light with a carefully structured pattern of holes in a simple metal plate, to make it much easier to tell if there are any optical misalignments.
AMI allows for a precise test pattern that can help correct any issues with JWST's focus. (Image credit: Anand Sivaramakrishnan/STScI)
Hunting blurry pixels
We wanted to use this mode to observe the birth places of planets, as well as material being sucked into black holes. But before any of this, AMI showed Webb wasn't working entirely as hoped.
At very fine resolution — at the level of individual pixels — all the images were slightly blurry due to an electronic effect: brighter pixels leaking into their darker neighbors.
This is not a mistake or flaw, but a fundamental feature of infrared cameras that turned out to be unexpectedly serious for Webb.
In a new paper led by University of Sydney PhD student Louis Desdoigts, we looked at stars with AMI to learn and correct the optical and electronic distortions simultaneously.
We built a computer model to simulate AMI's optical physics, with flexibility about the shapes of the mirrors and apertures and about the colours of the stars.
We connected this to a machine learning model to represent the electronics with an "effective detector model" — where we only care about how well it can reproduce the data, not about why.
After training and validation on some test stars, this setup allowed us to calculate and undo the blur in other data, restoring AMI to full function. It doesn't change what Webb does in space, but rather corrects the data during processing.
It worked beautifully — the star HD 206893 hosts a faint planet and the reddest-known brown dwarf (an object between a star and a planet). They were known but out of reach with Webb before applying this correction. Now, both little dots popped out clearly in our new maps of the system.
This correction has opened the door to using AMI to prospect for unknown planets at previously impossible resolutions and sensitivities.
It works not just on dots
In a companion paper by University of Sydney PhD student Max Charles, we applied this to looking not just at dots — even if these dots are planets — but forming complex images at the highest resolution made with Webb. We revisited well-studied targets that push the limits of the telescope, testing its performance.
With the new correction, we brought Jupiter's moon Io into focus, clearly tracking its volcanoes as it rotates over an hour-long timelapse.
As seen by AMI, the jet launched from the black hole at the centre of the galaxy NGC 1068 closely matched images from much-larger telescopes.
Finally, AMI can sharply resolve a ribbon of dust around a pair of stars called WR 137, a faint cousin of the spectacular Apep system, lining up with theory.
The code built for AMI is a demo for much more complex cameras on Webb and its follow-up, Roman space telescope. These tools demand an optical calibration so fine, it's just a fraction of a nanometre — beyond the capacity of any known materials.
Our work shows that if we can measure, control, and correct the materials we do have to work with, we can still hope to find Earth-like planets in the far reaches of our galaxy.
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- <![CDATA[ Future pandemics are a 'certainty' — and we must be better prepared to distribute vaccines equitably, says Dr. Seth Berkley ]]>
- Months before COVID-19 was officially declared a pandemic, public health leaders were poring over the early data coming out of China and preparing for the worst.
Dr. Seth Berkley — a renowned infectious-disease epidemiologist and former CEO of Gavi, an international organization aimed at improving children's vaccine access — was among those leaders. In January 2020, Berkley and colleagues were working to establish an infrastructure so that, if and when scientists created vaccines for this novel virus, the shots wouldn't be hoarded by high-income countries and denied to poor nations.
Now, Berkley has released a new book — "Fair Doses: An Insider's Story of the Pandemic and the Global Fight for Vaccine Equity" (University of California Press, 2025) — that recounts how that initiative unfolded and what lessons were learned through the process, while underscoring why the broader fight for vaccine equity is far from finished.
On January 23, 2020, I was high up in the Swiss Alps in Davos, attending the World Economic Forum (WEF). I was at Davos as the CEO of Gavi, the Vaccine Alliance, the largest purchaser of vaccines in the world and which worked to provide new and underutilized vaccines to children in developing countries — countries in which about half the world's children live. As usual, I was preoccupied with how we could do a better job protecting the world with vaccines for new and old diseases. And there were murmurs of a new epidemic of respiratory disease caused by a novel coronavirus in China on the horizon.
At the bar of the Hard Rock Hotel my wife, Cynthia [an academic physician and consultant], and I met with Richard Hatchett, CEO of the Coalition for Epidemic Preparedness Innovations (CEPI). Over nachos and drinks, we started to talk through what was likely to happen with the new coronavirus, which would later be named COVID-19. Discussion about the disease hadn't really reached a high political level and was not formally on the Davos agenda, but concern was growing, and many people during that week asked us our opinions.
The first question we discussed was whether this was just going to be a worrisome outbreak or the Big One that epidemiologists had long warned might come. So far, we only had official confirmation of a point outbreak, spreading from animals at the Wuhan live animal market to humans. But on the nerdy LISTSERVs about infectious disease and epidemics, there was already a lot of chatter about how the virus might be spreading from person to person, which is a huge red flag in our field. We agreed that there was potential for the new virus to spread dramatically. Regardless of whether this was or was not the Big One, we needed to prepare.
Such a scenario creates a problem for all countries, even those with access to the vaccines. But to me a far bigger concern was the unfairness of high-income countries' self-interest. People in developing nations without access to vaccines were historically already the most vulnerable to disease and the most likely to suffer complications if they got sick. They already had limited access to the most basic medical treatment.
Improving the delivery of existing vaccines and building up better delivery systems is the best way to detect outbreaks early, prepare communities for outbreaks of disease, and ensure health systems aren't overwhelmed in an emergency — as well as strengthen our epidemic stockpiles.
If vaccines against the disease could be made — and at the time, we were far from certain they could be — we knew that stocks would be quickly bought up by the richest countries. The logical conclusion was that the bulk of the world's population, and most especially those in lower income, developing countries, would be locked out of these deals, and so denied timely access to whatever vaccine supplies became available.
That was where we thought we could help. So, Richard, Cynthia, and I talked through a rough outline of what would be needed to ensure equitable access to any COVID-19 vaccines that emerged and the roles that various organizations — such as CEPI, Gavi, UNICEF, and WHO — as well as the pharmaceutical companies might play to make that happen.
Imagining ourselves in the place of government decision-makers, we envisioned that they would have an incentive to participate in a mechanism that pooled risk by making advance purchase commitments for a wide variety of candidate vaccines. Their buy-in could help us pool demand, generating enough scale to incentivize increasing production and to negotiate the best prices on everyone's behalf. We wanted to promote solidarity, to publicize and meet lower-income country needs, and to create an early, strong global movement for equitable access.
Richard went from Davos back to London and talked with the CEPI team, I went back to Geneva to talk to the Gavi team and our Alliance partners WHO and UNICEF, and we started our collaboration. That joint effort became COVAX [COVID-19 Vaccines Global Access, an initiative to ensure equitable access to COVID-19 vaccines].
Our small team working on COVAX undertook what I believe was the most ambitious public health effort of the 21st century so far. The first COVAX dose was delivered to a COVAX-supported country 39 days after the first jab in the United Kingdom. Due to the time required for WHO to prequalify the vaccine, 43 days later the first doses were administered in Africa, in Ghana and Côte d'Ivoire. Forty-two days later, COVAX vaccines had been distributed to 100 countries. There were many delays due to export bans, vaccine nationalism, and manufacturing delays. But by the end of 2021, close to 1 billion doses had been distributed; by the end of 2022, COVAX had delivered more than 1.6 billion doses to people in the world's poorest countries and was estimated to have averted 2.7 million deaths in those countries. That's the fastest rollout of vaccines to developing countries ever.
WHO estimates that some 16 million people died during the first two years of the pandemic; we are still counting, and that number will doubtlessly grow. And COVID-19 is by no means the only infectious risk: Currently, about one in seven deaths, accounting for more than 7 million people a year, is due to an infectious disease. Millions of people die from diseases for which we already have vaccines.
It's hard to put numbers on the deaths that have been prevented by vaccines, but some estimates say that vaccines have saved more than half a billion lives over the past 70 years, the time period they have been routinely available. And this only covers the 30 or so vaccines we have against the more than 300 infectious diseases known to plague humanity.
More and better vaccines need to be developed, particularly for major killers such as tuberculosis, malaria, and HIV, and, hopefully, more cancers. And in the meantime, the risks for infectious diseases are shifting.
Even those of us who had been working in the field for years were surprised at how poorly prepared the world was for an emergency of this magnitude. What's more, we faced the perils of vaccine nationalism, vaccine diplomacy, and the sometimes-selfish behaviors of manufacturers and world leaders. It was clear from the start that we wouldn't be able to do this work perfectly. But we did our best, and I've sought to set down both what we did and what I wish we could have done differently so that we can learn from our history.
As the world continues to recover from the worst of the pandemic years, we may not relish thinking about another pandemic ahead. We face complacency, fatigue, and a growing distrust of both science and institutions, fed by intentional disinformation that spreads rapidly online. But we also have an opportunity to harness what we've learned to do better next time — and there is epidemiologic certainty that a next time will come. When it does, we need to have robust public health systems in place, and ideally, vaccines.
Fair Doses: An Insider's Story of the Pandemic and the Global Fight for Vaccine Equity
"Fair Doses" is a story of vaccines: how they came about, why they are important, and how they have been made globally available — although our quest for vaccine equity is still ongoing. In this fascinating deep dive into vaccines, Dr. Seth Berkley, an internationally recognized infectious-disease epidemiologist and public health leader, offers an inside view of the challenges of developing and disseminating vaccines for a broad swath of illnesses, from Ebola to AIDS to malaria and beyond.View Deal
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- https://www.livescience.com/health/medicine-drugs/future-pandemics-are-a-certainty-and-we-must-be-better-prepared-to-distribute-vaccines-equitably-says-dr-seth-berkley
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- Tue, 28 Oct 2025 11:00:00 +0000
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- <![CDATA[ 'This is a completely different level of anti-vaccine engagement than we've ever seen before,' says epidemiologist Dr. Seth Berkley ]]>
- Within weeks of the first cases of a "mysterious pneumonia-like illness" being reported in Wuhan, China, public health leaders were convening to assess the threat and shore up systems to mitigate the potential harm to come. This work started unfolding months before COVID-19 would be officially declared a pandemic.
Dr. Seth Berkley — a renowned infectious-disease epidemiologist and former CEO of Gavi, an international organization aimed at improving children's vaccine access — was one figure at the forefront of the effort to ensure future COVID-19 vaccines would be distributed to the world's poorest nations. In his new book "Fair Doses: An Insider's Story of the Pandemic and the Global Fight for Vaccine Equity" (University of California Press, 2025), Berkley recounts those pandemic-era efforts and reflects on what went right and what went wrong.
Live Science spoke with Berkley about the book and the lessons we should take forward into the world's next big outbreak — the emergence of which, Berkley argues, is a matter of "when," not "if."
Nicoletta Lanese: What was the impetus to write this book?
Dr. Seth Berkley: When the book was written, the real purpose of it was to capture the experience [of the pandemic], post-COVID and post-COVAX. COVAX [COVID-19 Vaccines Global Access] was an initiative we put together when we realized that this looked like it was going to become a more severe infection. In doing that, we had all kinds of problems, but in the end, we did do the fastest and largest rollout of vaccines in history. We ended up with 57% of people in the developing world, the poorest 92 countries, getting coverage with primary doses, versus 67% globally — so not perfect equity, but better than it had ever been done before.
Dr. Seth Berkley. (Image credit: Courtesy of University of California Press)
What I was worried about is [that] people wouldn't capture the lessons learned, both good and bad. The book tries to explain what it took to get there, and also who were the good players, who were the bad players.
Now, since the book was written, the world has changed dramatically. I couldn't — I mean, I suppose I could have ripped the book up and started writing again. I didn't do that, but I did have a chance to say in the preface, and then later on at the end of the book, how much had changed, given the intense anti-vaccine attitudes that we're seeing right now in the U.S. government, particularly in the secretary of health and human services [HHS], Robert Kennedy Jr., who is a long-term vaccine skeptic and a conspiracy theorist on these things.
It's obviously quite concerning in regard to how that may affect Americans. But also it's important for Americans to understand that the vaccine work that's done in other countries also affects America, because the diseases we get come from both inside and outside.
NL: On that point, we've seen the U.S. withdraw support from initiatives that support vaccine equity globally. What are the potential impacts of that?
SB: So if we go back — I'll use a period of 50 years, for convenience — less than 5% of people in the world received even a single dose of vaccine. Not all the doses that were recommended — a single dose. And we've gone from that level up until vaccines, now, are the most widely distributed health intervention in the world. Along with that, we've seen a 70% reduction in vaccine-preventable disease deaths, and we've seen a more than 50% reduction in under-5 child mortality, directly as a result of this type of work.
So this is a really big deal. We've also seen control of many infectious diseases: the eradication of smallpox, the almost complete elimination of wild polio, the control of measles in many countries, etc. etc. Those are the successes. But the idea now is that we back away from this, when we have these infectious diseases that are still a risk — and as we've recently seen in the U.S., we've had some big measles outbreaks.
The U.S. actually had received the status of having eliminated endogenous measles infections, meaning that when new infections would occur, they had to come from outside. Now, the U.S. is at risk of losing that designation. This is why it's so important to think about it globally, because if we see many more measles infections occurring in other countries and given the movement of people, you're eventually going to see those cases in the United States if vaccine rates go down. And they are going down.
We've got a situation where people are discrediting experts and putting people in place who do not have expertise and have preconceived notions on vaccines. They say they're trying to increase trust, but I don't see how that increases trust. And we're now fractured in the U.S.; you've seen most recently this idea that states are coming together to put out their own recommendations. Professional societies are putting out recommendations, instead of having one definitive set. In the end, I don't think that helps with confidence.
NL: Do you feel these shifts in the U.S. stem from an amplification of an old problem we've had, or more from a brand-new issue?
SB: It's a little of both. Vaccine hesitancy has existed from the first vaccine, which was in the 1700s smallpox right after the original vaccine was shown to work. There were cartoons showing — because the vaccine was derived from cows — there were pictures of people with cow horns growing out of their heads and all kinds of things like that. So this is not a new problem.
What is new is having the intense politicization of this — the idea that one political party more than another political party has these beliefs and therefore acts on them, so there are different coverage slates for vaccines for different parties. And then finally, [there's] the fact that you've got government leaders that are pushing these conspiracy theories and discrediting institutions that have scientific professionals and mechanisms that have been set up to try to have the best science possible.
During COVID, we saw Russian bots and Chinese bots that were providing disinformation, and of course, this spread like wildfire. But also for the first time that I know of, we had the U.S. government, the Defense Department, putting out misinformation to try to discredit the Chinese vaccine. So this is a kind of warfare that's going on that has some terrible effects. … This is a completely different level of anti-vaccine engagement than we've ever seen before.
By definition, everybody should invest their marginal dollars in preventing disease before they get to investing in treating diseases — but that's not human nature.
Dr. Seth Berkley, Brown University
NL: You often hear the argument that, because vaccines have worked so well, people lack a fear of vaccine-preventable diseases. Do you see any validity to that?
SB: When you look at this new era of misinformation — as I said, there's always been vaccine misinformation. But the difference is, if you are in a country that has very high vaccination rates and therefore the diseases have virtually disappeared, it's very easy for a parent to say, "I don't want my kid to be injected with something. … I don't know anything about these diseases. I've never seen them. How bad can they be?" So that's one side of it.
When you're living in a developing country and these diseases are still there, you see kids that have morbidity from these diseases. You see people paralyzed from polio. You see people who are blind or deaf from German measles [also called rubella]. And so your benefit-harm ratio is seen as different in these different populations. And it's the job of science to ask the question, what is the benefit-to-cost ratio of these products?
The other thing that's really hard is, because we don't see these diseases, you don't know the kind of really severe side effects that occur. In measles, there's a disease called subacute sclerosing panencephalitis. It's a fairly rare disease — but when it happens, the child's brain dissolves, and there is nothing you can do.
The challenge is that you don't want people to live in fear all the time, but no parent wants that to happen to their child. It's about how you can both educate and have people aware of the side effects of these diseases, and even ones that are rare. That's really the challenge right now. I think the only way to solve that is education.
NL: Another focus of the book is a roadmap to global vaccine equity. What do you see as the biggest obstacles to that goal?
SB: First of all, the stuff we've just discussed, which is having awareness of the value of vaccination, and that's critical for populations everywhere in the world. And obviously keeping that knowledge up even when the diseases get rarer and rarer is really important.
The second critical point is having access to vaccines. What Gavi was able to do was, by consolidating the buying power of many different countries, we were able to drive the price [of routine vaccines] down 98% from that of what it cost in the United States, which makes it really affordable. Vaccines are cost-effective even at higher prices, but obviously the more affordable they are, the better it is. So a priority is making sure that those products are available and that they are being produced in the quantities they need.
The third part of it is having delivery systems in place, and this is really a challenge. As I mentioned at the beginning, vaccines are the most widely distributed health intervention, and about 90% of families in the world have access to routine vaccines. … Reaching [the last 10%] with that system not only provides vaccines but also provides health access, and it also means there is an early warning system to make sure that there are health workers for everybody — so that if there are outbreaks or weird diseases that appear, you have a system that can report back.
Lastly, I'd say that there's importance in having global surveillance for new infections. It's evolutionarily certain we're going to have new outbreaks and new pandemics, and that warning system is critical for everybody in the world. Building this prevention system, which is very cost-effective, is the right thing to do everywhere, and it's a matter of making that a priority.
NL: I want to come back to the point that epidemics and pandemics are essentially inevitable. With that in mind, how do we prepare?
SB: Epidemics are evolutionarily certain — certainly, that's true. So the first part of that is, how do we prepare for things that we know, like flu, like COVID, like hemorrhagic fevers? These are things that we now have interventions for. And how do we make sure that the world is ready, that there are systems of laboratories, that there are stockpiles of vaccines ready to go, and [that there's] the ability to scale them up?
Unfortunately, a lot of that is now being broken apart. At this moment in time, we [the United States] are firing people in major health agencies. We're pulling out of the World Health Organization. We're changing our development assistance and stopping training of scientists, etc. etc. So we are breaking down the systems that exist to deal with that [preparation for known threats], which is a real problem.
Then, when you get to the "unknown unknowns," you also want to have the science ready to go. There's a good example right now, of pulling out of mRNA vaccines. [The HHS recently pulled funding from research-and-development projects focused on mRNA vaccines.] mRNA vaccines may not be perfect; they may not even be the best vaccines for some diseases. But they are the fastest, because you can make them very quickly from the genome. Then you can, in essence, "print" the vaccine and scale it up very quickly.
In the case of a very severe pandemic that has a very high mortality rate, that is the best way: to make an mRNA vaccine to deal with it. The idea that we would not want to continue to work on mRNA — improving it, making it better — and instead we're just pulling research out seems to me to be very, very shortsighted indeed.
NL: To continue on mRNA, would you say that in a pandemic scenario, it's speed that's the most crucial element of the vaccine? Or are there other advantages to the mRNA platform?
SB: The absolute advantage there is speed. And remember, COVID had a mortality rate of about 1.5%, 2%. Some of the other diseases that we know of, that potentially could spread, have mortality rates of 20%, 30%, 40%, 50%. If you had something like that — that's a respiratory pathogen spreading quickly with very high mortality rates — every hour counts in terms of speed.
So mRNA is the fastest. … It may be that, once you have mRNA vaccines, you may want to shift to other vaccines that may give longer duration of protection, give better immune responses, etc. [for a given pathogen]. But you can't make those in the same time frame, so it may be a handoff from one to another.
One of the challenges in COVID was that there were over 200 different vaccines that were made, but mRNA was so fast out of the block that others really didn't get a chance to become successful. If I use an example, the Novavax vaccine, which is a protein[-based vaccine], never really got global traction, even though it was a very effective, very safe vaccine that maybe had a longer duration of protection.
The challenge is, how do we, in that setting, have comparative science to say which are the best products? That will not be done by the pharmaceutical sector because they don't have any incentive to do head-to-head comparisons. That needs to be done by international agencies or by governments.
NL: What else can readers expect from "Fair Doses"?
SB: The book is also filled with lots of interesting nuggets of stories of who behaved well and who didn't behave well during the pandemic, and that includes political leaders, that includes pharmaceutical companies, that includes agencies. So it gives a nuanced understanding of what that time really looked like.
We came together, along with our partners, to try to see if we could change the normal dynamic that occurs in a pandemic, which is wealthy countries buy all the doses and there's no doses available for anybody else. That was our goal going into it, and the book tells the story of how we put together this initiative, how we raised the $12.5 billion necessary to buy vaccines, how we ultimately delivered more than 2 billion doses to 146 countries.
One of the questions is, how do we do better? What do we learn from that? And that's something we try to explore in the book.
Editor's note: This interview has been lightly edited for length and clarity.
This article is for informational purposes only and is not meant to offer medical advice.
Fair Doses: An Insider's Story of the Pandemic and the Global Fight for Vaccine Equity
"Fair Doses" is a story of vaccines: how they came about, why they are important, and how they have been made globally available — although our quest for vaccine equity is still ongoing. In this fascinating deep dive into vaccines, Dr. Seth Berkley, an internationally recognized infectious-disease epidemiologist and public health leader, offers an inside view of the challenges of developing and disseminating vaccines for a broad swath of illnesses, from Ebola to AIDS to malaria and beyond.View Deal
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- https://www.livescience.com/health/medicine-drugs/this-is-a-completely-different-level-of-anti-vaccine-engagement-than-weve-ever-seen-before-says-epidemiologist-dr-seth-berkley
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- Tue, 28 Oct 2025 11:00:00 +0000
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- <![CDATA[ Glowering 'skull' stares upward from a giant volcanic pit in the Sahara — Earth from space ]]>
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What's in the photo? A skull-like structure within a volcanic caldera appears to stare up into space
Who took the photo? An unnamed astronaut on board the International Space Station (ISS)
When was it taken? Feb. 12, 2023
This eerie astronaut photo shows a ghostly structure with a skull-like appearance glowering up into space from the floor of a giant volcanic pit in the Sahara.
The cranium lookalike is located on the floor of Trou au Natron, also known as Doon Orei — a 3,300-foot-wide (1,000 meters) volcanic caldera, or crater, in northern Chad. (Trou au Natron translates to "natron hole" in French, while Doon Orei means "big hole" in Teda.)
The volcanic pit was carved out by a massive eruption hundreds of thousands of years ago and sits at the heart of the Tibesti Massif, a 300-mile-long (480 kilometers) mountain range that stretches across the center of the Sahara desert through Chad and Libya, according to NASA's Earth Observatory.
When viewed from space, the caldera's floor has an unmistakable skull-like appearance. But when viewed from ground level (see below), it looks almost unrecognizable.
The skull takes on a more deformed appearance when viewed from the cladera's rim. (Image credit: Gerhard Holub/Wikimedia)
The white color of the skull's mouth, nose and cheeks is the result of natron, a naturally occurring mixture of sodium carbonate decahydrate, sodium bicarbonate, sodium chloride and sodium sulfate. This salty mix is extremely flaky and looks like cracked paint when viewed up close.
The eyes and nose hole areas are actually cinder cones — steep conical hills built around volcanic vents that tower above the rest of the caldera floor. The darker area to the left of the face is the shadow cast by the tall rim of the crater, which helps give the skull its distinctive shape.
From ground level, the skull shape completely disappears. Instead, all you can see is tall cinder cones tower above a sea of flaky natron. (Image credit: Alexios Niarchos/Wikimedia)
Trou au Natron is barren and lifeless today, but experts believe it was once a thriving glacial lake. In the 1960s, researchers discovered fossils of sea snails and plankton beneath the pit's natron-covered floor, which date back to 14,000 years ago. In 2015, a follow-up expedition found algal fossils that date back as far as 120,000 years ago.
The caldera has been volcanically dormant since shortly after it formed. However, it is situated close to Tarso Toussidé, a broad volcanic feature covered with a sea of frozen lava (located just beyond the top of the satellite image). Tarso Toussidé is home to a stratovolcano that is still believed to be volcanically active despite not erupting for more than 12,000 years, according to the Smithsonian Institution's Global Volcanism Program.
Trou au Natron is not the only volcanic structure that looks like a skull when viewed from space: The Chiltepe Peninsula in Nicaragua's Lake Managua has a pair of volcanic lakes, each sitting within its own caldera, which give the landmass a very similar appearance to the caldera in Chad.
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- https://www.livescience.com/planet-earth/volcanos/glowering-skull-stares-upward-from-a-giant-volcanic-pit-in-the-sahara-earth-from-space
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- Tue, 28 Oct 2025 08:00:00 +0000
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- <![CDATA[ Differences in red blood cells may have 'hastened the extinction' of our Neanderthal cousins, new study suggests ]]>
- A fatal genetic incompatibility between Neanderthals and modern humans may have hastened the extinction of our ancient cousins, new research suggests.
Researchers found that different versions of a gene tied to red blood cell function may have caused Neanderthal-human hybrid women to miscarry their fetuses.
When Neanderthals and early modern humans met in Eurasia around 45,000 years ago, "they exchanged genes — and may also have passed on hidden reproductive risks that shaped the fate of both lineages," Patrick Eppenberger, co-head of the Evolutionary Pathophysiology and Mummy Studies Group at the Institute of Evolutionary Medicine in Zurich, and colleagues wrote in a study posted to the preprint database bioRxiv Sept. 29. (It has not been peer-reviewed yet.)
The researchers focused on the PIEZO1 gene, which affects red blood cells and is found in both modern humans (Homo sapiens) and Neanderthals. They discovered that the PIEZO1 gene differed between Neanderthals and modern humans.
The Neanderthal variant, which is similar to the variant found in other great apes, allowed the hemoglobin in red blood cells to cling more tightly to oxygen molecules, while the novel H. sapiens variant allowed oxygen to be passed more efficiently into surrounding tissue. Neanderthals may have maintained the original variant because it was beneficial for surviving extreme cold and periods of starvation, the researchers suggested.
But when maternal blood has abnormally high amounts of oxygen bound to hemoglobin, that means low levels of oxygen are passed on to a fetus through the placenta. This can cause hypoxia (oxygen deficiency) or restricted growth of the fetus or miscarriage.
But because of the way the PIEZO1 gene variants are inherited, the incompatibility would arise only when a hybrid Neanderthal-human mother mated with a modern-human father or with a hybrid Neanderthal-human father.
"Many of their offspring would fail to survive," the researchers wrote. This, in turn, would mean Neanderthal women would pass on less of their mitochondrial DNA, which is carried in the egg and passes from mother to child, the authors wrote in the study. Over the course of several generations of mating between Neanderthals and humans, this may have significantly compromised hybrid Neanderthals' ability to have kids, the researchers noted.
"The PIEZO1 incompatibility may have accelerated the demise of the Neanderthals by gradually eroding their reproductive capacity whenever the two groups interacted," they wrote.
April Nowell, a Paleolithic archaeologist at the University of Victoria who was not involved in the study, told Live Science in an email that the study adds a much-needed piece of the puzzle to the question of Neanderthal extinction — namely, maternal-fetal incompatibility in oxygen transfer during pregnancy.
"It's super interesting that an allele [gene variant] that may have saved Neanderthals in the past was their ultimate undoing when they began to interbreed with modern humans," Nowell said.
John Hawks, a biological anthropologist at the University of Wisconsin who was not involved in the study, told Live Science in an email that the maternal-fetal incompatibility of PIEZO1 was intriguing and analogous to other genetic blood conditions, such as Rh factor incompatibility in modern humans.
"This is one of many potential cases where the gene variant coming from an archaic population had some bad effects, causing it to decline in frequency over time in modern people," Hawks said.
But PIEZO1 is not the final answer to the question of Neanderthal extinction.
"There are no single-gene explanations for what was a long and complicated interaction across many archaic human groups, as modern humans entered the places where they lived and interacted with them," Hawks said.
Eppenberger and colleagues emphasized in their study that the effect of interbreeding between Neanderthals and modern humans was likely drawn out and subtle — "more akin to rust weakening a structure than a single catastrophic blow" — and that more research along these lines is needed.
"It is worth pondering how many other loci in the genome might have similarly given rise to hybrid incompatibilities," they wrote.
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- https://www.livescience.com/archaeology/human-evolution/differences-in-red-blood-cells-may-have-hastened-the-extinction-of-our-neanderthal-cousins-new-study-suggests
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- Mon, 27 Oct 2025 21:52:27 +0000
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- <![CDATA[ Is the Oura Ring Gen 4 worth it? Here's what we think after four months of testing ]]>
- We named the Oura Ring Gen 4 as the best option overall in our guide to the best smart rings on the market, and for a good reason. Not only is it the most size-inclusive and customizable model we have tested, but it is also exceptionally accurate and brimming with useful health-tracking features. It comes with a beautifully designed app, too, and thanks to its easy-to-understand health advice, it works well for both beginners and fitness professionals. The Oura Ring Gen 4 is a fabulous fitness tracker, but is it actually worth it in the long term?
We will not beat around the bush here — it is one of the most expensive smart rings out there. The Oura Ring Gen 4 costs anywhere from $349 for the basic silver, all the way up to a whopping $499 for the gold and ceramic versions. Unlike the vast majority of its competitors, it also requires a monthly subscription for full access to its features. The Oura membership costs $5.99 USD per month or $69.99 USD per year, nearly as much as Garmin Connect+ and other premium fitness platforms. It is quite a steep investment, even when compared to many top-shelf smartwatches.
So, do the benefits outweigh the costs? We are now starting our fifth month with the Oura Ring Gen 4, so we have a good understanding of what this smart ring can and can't do, and whether it has the potential to change your lifestyle for the better. As such, we are more than well-equipped to answer the question. Here is our verdict on the overall value of the Oura Ring Gen 4 after four months of intense testing.
Oura Ring Gen 4 long-term review
Oura Ring Gen 4: Comfort and durability
Heavy and chunky
Withstands water and harsh temperatures
Minor scratches only, no scuffs or dents
The Oura Ring Gen 4 is one of the heaviest smart rings we have tested. (Image credit: Anna Gora)
If there is one thing in which the Oura Ring Gen 4 consistently outshines its competitors, it is the durability. This smart ring has graced our hand daily for four months straight, including when we were training in the gym, hiking outdoors and swimming in the sea, and it has never succumbed to accidental damage or design-related issues that blighted some of the other smart rings we tested. True, our Oura Ring Gen 4 did end up suffering a few scratches here and there, but they are so minor we can barely see them anyway. Not to mention, these scratches are definitely less visible than the ones sustained by our Ultrahuman Ring AIR (we managed to severely bruise the surface of this smart ring by simply holding a glass water bottle, and after just two weeks of testing).
That is not all — the Oura Ring Gen 4 also impressed us with its high resistance to temperature changes. Smart rings are relatively tiny and therefore generally prone to overheating when exposed to blazing sunshine or hot water. The Amazfit Helio ring, for example, would regularly overheat and shut down on us when we wore it while exercising outdoors during the scorching months of June and July. The Oura Ring Gen 4, on the other hand, has never malfunctioned in that way.
Chunky and cumbersome, the Oura Ring Gen 4 can be quite uncomfortable to wear. (Image credit: Anna Gora)
All in all, this smart ring is a tough cookie. However, that does not mean that it is also comfortable to wear. The Oura Ring Gen 4 is significantly heavier and chunkier than most other smart rings. Even after nearly five months of wearing it, we still can't fully get used to its sheer size and weight. We always feel its presence, cumbersome and in the way, which can be particularly disruptive when exercising or clenching a fist. This is not something we experienced with other smart rings we tested; quite the opposite. With the Amazfit Helio and Ultrahuman Ring AIR, for example, we could easily forget about their existence regardless of what we were doing.
Oura Ring Gen 4: Performance and accuracy
Consistent battery life
No major connectivity issues
Very good stat accuracy
The Oura Ring Gen 4 has served us well for the past four months. Most notably, we have not experienced any major connectivity issues, and this is our pet peeve when it comes to smart rings. Poor app connectivity and patchy data transfer often undermined our experience with these devices in the past (to put it lightly), so it was quite refreshing to see that it is not the case with the Oura Ring Gen 4. True, this smart ring may take a good few seconds to analyze your stress and sleep data when you open the app first thing in the morning, but it does not lag or disconnect for no apparent reason.
Battery life is another plus point. According to the brand, the Oura Ring Gen 4 lasts up to eight days on a single charge, and that is largely true in our experience. More importantly, it stays that way over time — after nearly five months of testing, its battery life is still as good as it was on day one (and that is not something we see often in fitness trackers in general). Of course, the eight-day threshold is not set in stone, and certain activities, such as tracking exercise sessions, will inevitably speed up the battery drain. However, it does not do it anywhere near as much as it does in other smart rings we tested. Looking back, we have never had to charge our Oura Ring Gen 4 more than once per week.
The Oura Ring Gen 4 boasts up to eight days of battery life. (Image credit: Anna Gora)
Last, but not least, the tracking accuracy. The Oura Ring Gen 4 does a particularly good job of measuring heart rate, stress and sleep quality, and has been largely spot-on with detecting when we fall asleep and when we wake up. This stat accuracy then feeds into the tailored sleep and recovery advice, helping to make it genuinely useful and helpful for the user. Speaking of these personalized tips and guidelines, they get even better with time, and that is because the Oura Ring Gen 4 is actively 'learning' how your body works and what your lifestyle typically looks like. This machine learning prowess proved to be particularly useful for our menstrual cycle predictions — they got scarily accurate after just three months of using this smart ring.
The Oura Ring Gen 4 has some of the best sleep-tracking features on the market. (Image credit: Anna Gora)
We are not fans of the activity detection feature, though. In theory, the Oura Ring Gen 4 should automatically pick up on the type and duration of your activities, and then allow you to accept or amend these logs in the app. All in the bid to save time. In practice, it is way more hassle than it needs to be. The activity detection feature can be quite overzealous, either logging minor movements as workouts (my personal favorite is when our Oura Ring Gen 4 thought we had a dancing workout when in reality we took a quick shower), or mislabeling our activities (cycling instead of running, etc.). Correcting all those little mistakes can be quite time-consuming, and even downright annoying in the long term. So, let us warn you: If you end up buying the Oura Ring Gen 4, be prepared to spend a few minutes each day cleaning up your activity logs.
Is the Oura Ring Gen 4 worth it in the long term?
All in all, the Oura Ring Gen 4 has stood the test of time, consistently providing us with a great user experience over the past five months. However, the question here is not about the quality of this smart ring, but rather about its overall functionality and value for money. This is where things get slightly more nuanced.
If stress management and maintaining good quality sleep are at the very top of your priority list, the Oura Ring Gen 4 is a worthy investment. Hands down, it is the best sleep tracker we have tested, and you would be hard-pressed to find a wearable with a better combination of build quality, tracking accuracy and customizable features. We found the Oura Ring Gen 4 genuinely helpful in establishing our sleep-wake cycle, spotting patterns in our stress levels or monitoring our post-exercise recovery, and we are confident it could do that for you, too.
The Oura Ring Gen 4 can help manage your stress better. (Image credit: Anna Gora)
However, a worthy investment does not automatically mean the best possible option. We have tried and tested enough fitness wearables to know that even models on the more affordable end of the spectrum are now getting increasingly better at assessing sleep quality and stress levels. The Amazfit Balance smartwatch is a good example here — this Chinese-made alternative to Garmin watches is subscription-free and costs only $149, yet it provides some impressive sleep-focused tracking tools and genuinely helpful features for managing stress. It may still fall slightly behind the Oura Ring Gen 4 in terms of the depth and detail of its metrics, but for those who do not need or want science-grade precision, the Amazfit Balance can provide just as much value.
All in all, it all comes down to whether you are willing to pay for the subscription. Personally, we really like our Oura Ring Gen 4, even though its chunky design can drive us crazy at times, and we will continue to use it for the foreseeable future. However, we can easily imagine a life without this smart ring.
The Oura Ring Gen 4 is an excellent piece of kit, but it is quite expensive in the long term, too. (Image credit: Anna Gora)
✅ Buy it if: You want an accurate and detailed sleep tracker that does not compromise on durability, app connectivity or battery life. The Oura Ring Gen 4 is the best-performing smart ring we have tested, and its sleep-tracking features are some of the best we have seen.
❌ Do not buy it if: You are on a budget. The Oura Ring Gen 4 is a great piece of kit, but, in all fairness, you can get a very similar user experience with some of the subscription-free smartwatches.
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- https://www.livescience.com/health/oura-ring-gen-4-review-after-four-months-of-testing
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- 7XDjmAxKSujg3EwHiTFtpe
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- Mon, 27 Oct 2025 21:00:00 +0000
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- <![CDATA[ Being mean to ChatGPT increases its accuracy — but you may end up regretting it, scientists warn ]]>
- Artificial intelligence (AI) chatbots might give you more accurate answers when you are rude to them, scientists have found, although they warned against the potential harms of using demeaning language.
In a new study published Oct. 6 in the arXiv preprint database, scientists wanted to test whether politeness or rudeness made a difference in how well an AI system performed. This research has not been peer-reviewed yet.
To test how the user's tone affected the accuracy of the answers, the researchers developed 50 base multiple-choice questions and then modified them with prefixes to make them adhere to five categories of tone: very polite, polite, neutral, rude and very rude. The questions spanned categories including mathematics, history and science.
Each question was posed with four options, one of which was correct. They fed the 250 resulting questions 10 times into ChatGPT-4o, one of the most advanced large language models (LLMs) developed by OpenAI.
"Our experiments are preliminary and show that the tone can affect the performance measured in terms of the score on the answers to the 50 questions significantly," the researchers wrote in their paper. "Somewhat surprisingly, our results show that rude tones lead to better results than polite ones.
"While this finding is of scientific interest, we do not advocate for the deployment of hostile or toxic interfaces in realworld applications," they added. "Using insulting or demeaning language in human-AI interaction could have negative effects on user experience, accessibility, and inclusivity, and may contribute to harmful communication norms. Instead, we frame our results as evidence that LLMs remain sensitive to superficial prompt cues, which can create unintended trade-offs between performance and user well-being."
A rude awakening
Before giving each prompt, the researchers asked the chatbot to completely disregard prior exchanges, to prevent it from being influenced by previous tones. The chatbots were also asked, without an explanation, to pick one of the four options.
The accuracy of the responses ranged from 80.8% accuracy for very polite prompts to 84.8% for very rude prompts. Tellingly, accuracy grew with each step away from the most polite tone. The polite answers had an accuracy rate of 81.4%, followed by 82.2% for neutral and 82.8% for rude.
The team used a variety of language in the prefix to modify the tone, except for neutral, where no prefix was used and the question was presented on its own.
For very polite prompts, for instance, they would lead with, "Can I request your assistance with this question?" or "Would you be so kind as to solve the following question?" On the very rude end of the spectrum, the team included language like "Hey, gofer; figure this out," or "I know you are not smart, but try this."
The research is part of an emerging field called prompt engineering, which seeks to investigate how the structure, style and language of prompts affect an LLM's output. The study also cited previous research into politeness versus rudeness and found that their results generally ran contrary to those findings.
In previous studies, researchers found that "impolite prompts often result in poor performance, but overly polite language does not guarantee better outcomes." However, the previous study was conducted using different AI models — ChatGPT 3.5 and Llama 2-70B — and used a range of eight tones. That said, there was some overlap. The rudest prompt setting was also found to produce more accurate results (76.47%) than the most polite setting (75.82%).
The researchers acknowledged the limitations of their study. For example, a set of 250 questions is a fairly limited data set, and conducting the experiment with a single LLM means the results can't be generalized to other AI models.
With those limitations in mind, the team plans to expand their research to other models, including Anthropic's Claude LLM and OpenAI's ChatGPT o3. They also recognize that presenting only multiple-choice questions limits measurements to one dimension of model performance and fails to capture other attributes, such as fluency, reasoning and coherence.
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- https://www.livescience.com/technology/artificial-intelligence/being-mean-to-chatgpt-increases-its-accuracy-but-you-may-end-up-regretting-it-scientists-warn
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- 4oA3qDJ4HCuXpGZbKQSWAU
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- Mon, 27 Oct 2025 16:45:00 +0000
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