Long before pottery became a common art form, the southern Levant underwent major environmental changes that stripped vegetation from hillsides and caused large amounts of clay-rich soil to accumulate in the valleys.

Now, a new study led by Amos Frumkin at the Hebrew University of Jerusalem suggests this process may have exposed Neolithic communities to the effects of intense fire on clay. Frumkin refers to this as the natural kiln hypothesis.

The study, published in Geomorphology, examined evidence from ancient sediments, cave deposits, and charcoal remains and identified two separate periods when wildfire and erosion impacted the area.

The Hills That Burned Twice

The two periods are separated by more than 100,000 years; the first of them was the last interglacial, lasting from about 129,000 to 116,000 years ago. The second was the early Holocene, which lasted from about 11,000 to 7,000 years ago, a period that corresponds with the establishment of farming communities in the region. The most intense burning occurred between 9,500 and 8,200 years ago.

Both periods left similar evidence. Small charcoal particles in ancient lake sediments indicate periods of increased burning. Chemical signatures in cave formations show the loss of vegetation and soil that followed. Frumkin notes that the scale and timing of the fires point toward climatic causes rather than increased human use of fire, although people in the region already used fire on a limited scale.

A Natural Kiln

Once the vegetation disappeared, the hillsides could no longer retain soil when it rained. The terra rossa clay, therefore, washed down the slopes and collected in low-lying areas like the Jordan and Dead Sea valleys, building up in thick layers. Since this redeposited clay was very fertile, Neolithic settlements tended to cluster in these areas.

Pottery appeared in the region during the same time period. Earlier petrographic studies show that local redeposited terra rossa clay provided the material for Yarmukian pottery from the Jordan Valley, the same material that erosion deposited in Frumkin’s study.

“A wildfire is normally seen only as a catastrophe, but environmental disruption can also expose people to new materials and new possibilities,” said Frumkin. “Neolithic communities in the Jordan Valley may have watched fire transform the clay beneath and around their settlements and realized that this process could be reproduced deliberately. If so, one of humanity’s most important technologies may have emerged partly from people learning to imitate what they had already seen nature do.”

The 120,000-Year Comparison

This earlier period can serve as a comparison for this hypothesis. Vegetation also declined, and clay deposited heavily during the last interglacial period; however, pottery did not appear after that event. Frumkin sees this as an example of a natural limitation because the required materials were available 120,000 years earlier, but there were no settled, agricultural societies to identify and replicate the process.

The comparison suggests that environmental conditions alone were not enough to produce pottery. The innovation may have emerged when these conditions intersected with a society capable of recognizing the opportunity and reproducing what it observed.

Frumkin stresses that the hypothesis is still speculative. Although the fires, the clay deposits, and the earliest pottery all come from roughly the same period, current dating techniques cannot establish the exact order of events. Further excavations might search for fire-baked clay beneath the oldest pottery layers and test whether wildfires in the Jordan Valley reached the temperatures needed to harden clay. Finding any pottery that clearly predates the major fire episode would challenge this hypothesis.

Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds an MBA, a Bachelor of Science in Business Administration, and a data analytics certification. His work focuses on breaking scientific developments, with an emphasis on emerging biology, cognitive neuroscience, and archaeological discoveries.

When a tunnel catches fire, temperatures inside the concrete lining can soar to 800 or 900 degrees Celsius, and the emergency response almost always involves dousing the structure with water. A new study suggests that this familiar firefighting image—flames followed by a torrent of cooling water—may be doing far more damage to the concrete than engineers have typically accounted for. Researchers investigating basalt fiber-reinforced concrete have found that how a fire-damaged structure is cooled can be as important as how hot it got in the first place, with water quenching consistently inflicting greater strength loss than slow, natural cooling across every temperature they tested.

The research, published in Case Studies in Construction Materials, systematically examined how heating temperature, cooling regime, fiber content, and impact loading combine to determine whether concrete survives a fire with its load-bearing capacity intact. The team, led by Yang Liu and colleagues including Delin Li, Jinyue Dong, Yingda Zhang, Xianliang Zhou, and Qiong Zhou, chose basalt fiber-reinforced concrete, or BFRC, as their test material because of the fiber’s unusual combination of properties. Basalt fibers, drawn from volcanic rock, offer high tensile strength, thermal stability up to melting points between 1350 and 1450 degrees Celsius, and a cost profile far more attractive than premium alternatives such as carbon fiber. This makes them an appealing candidate for tunnel linings, where fire resistance and economy must be balanced.

The experimental design was exhaustive. The researchers prepared a C35-grade concrete mix—the grade commonly recommended for tunnel design—using ordinary Portland cement, medium sand, and continuously graded gravel between 5 and 10 millimeters. Into this base mix they incorporated chopped basalt fibers, 12 millimeters long with a monofilament diameter of 17 micrometers, at volume fractions of 0, 0.1, and 0.2 percent. The fibers were added in small batches during dry mixing to prevent agglomeration, and the fresh concrete was cast into cylindrical specimens measuring 50 millimeters in diameter and 25 millimeters in height, then cured under standard conditions at 20 degrees Celsius and 95 percent relative humidity.

The thermal assault began in a high-temperature electric oven capable of reaching 1200 degrees Celsius. Specimens were heated at a controlled rate of 5 degrees Celsius per minute to target temperatures of 200, 400, 600, and 800 degrees Celsius, then held at temperature for a full hour to ensure the heat penetrated the interior. Half the specimens were then removed and allowed to cool naturally in ambient air, mimicking a structure left to cool on its own after a fire. The other half were plunged immediately into a tank of tap water, replicating the thermal shock of firefighting operations. After cooling, the water-immersed specimens were conditioned in air for seven days to return them to a natural moisture state before testing.

The dynamic mechanical properties were then probed using a split Hopkinson pressure bar, the workhorse instrument for measuring how materials behave under the extreme strain rates produced by impacts and blasts. The apparatus used bars 75 millimeters in diameter, made of high-strength steel with an elastic modulus of 210 gigapascals, with a striker bar propelled by compressed gas striking an incident bar that transmitted stress waves through the specimen. Three impact velocities—3.5, 4.4, and 5.2 meters per second—were tested, achieved by varying the operating gas pressure, with three specimens per condition. A thin pulse shaper was pasted at the impact end of the incident bar to smooth out high-frequency oscillations, and stress equilibrium between the two faces of each specimen was verified from strain-gauge signals, confirming the reliability of the data. Fragments from each impact were sieved through meshes ranging from 4.75 millimeters down to 75 micrometers so that a fractal dimension could be calculated, providing a quantitative measure of how thoroughly each specimen shattered.

The visual evidence of thermal damage followed a familiar but telling progression. At 200 degrees Celsius, the concrete surfaces turned bluish-gray, with no cracking. By 400 degrees, the color shifted to yellowish-gray, still structurally sound. At 600 degrees, fine cracks appeared along with slight surface peeling, and by 800 degrees the specimens showed severe cracking, spalling, and edge breakage. Water-cooled specimens generally exhibited more pronounced surface damage than their naturally cooled counterparts, and at 800 degrees the concave shape at the start of the stress-strain curve—evidence of pre-existing microcracks being closed under compression—was especially marked in the water-quenched samples.

The strength data told a stark quantitative story. For naturally cooled specimens containing 0.2 percent basalt fiber, the dynamic peak stress at an impact velocity of 3.5 meters per second fell from 51.1 megapascals at room temperature to 18.6 megapascals at 800 degrees—a reduction of 63.6 percent. Water cooling made matters worse across the board: at the same impact velocity, the reductions reached 23.9 percent at just 200 degrees and climbed to 64.9 percent at 800 degrees. Averaged across the temperature range, each 100-degree increment cost naturally cooled specimens roughly 6.7 to 8.0 percent of their strength, while water-cooled specimens lost about 7.5 to 8.1 percent per 100 degrees. The gap between the two cooling regimes widened at higher impact velocities: at 5.2 meters per second and 800 degrees, the water-cooled specimens suffered 6.4 percent greater strength loss than the naturally cooled ones, whereas at the lowest velocity the difference was a mere 1.3 percent. The explanation lies in competing timescales—at slow loading rates, cracks have time to propagate and dissipate energy, blunting the effect of water-induced damage, but at high rates the loading outpaces the material’s energy dissipation, and the microcracks created by thermal shock propagate catastrophically.

Against this backdrop of degradation, the basalt fibers demonstrated genuine protective power. At every temperature from 200 to 800 degrees, specimens with 0.2 percent fiber content outperformed both plain concrete and the 0.1 percent mix. At 400 degrees and an impact velocity of 3.5 meters per second, the naturally cooled fiber-reinforced specimens reached peak stresses of 40.1 megapascals, some 16.9 percent above plain concrete, while at 200 degrees under water cooling the 0.2 percent mix achieved 38.8 megapascals—a remarkable 32.4 percent improvement over unreinforced concrete. The mechanism, the authors explain, is architectural: randomly distributed fibers form a three-dimensional network that binds tightly with the cementitious matrix, reduces internal pores and cracks, and bridges microcracks before they can coalesce into fracture surfaces. But this protection has a ceiling. Above roughly 600 degrees, the fibers begin to degrade and lose their reinforcing capability, and the fiber-matrix interface—already weakened by thermal mismatch between fiber and paste—becomes a liability during water quenching.

Fractal analysis of the impact debris added another layer of insight. The fractal dimension of the fragments rose steadily with temperature, from around 1.82 at 200 degrees to above 2.3 at 800 degrees under the highest loading rate, indicating progressively finer and more complex fragmentation. Water-cooled specimens consistently shattered into finer pieces than naturally cooled ones, particularly at 600 and 800 degrees, confirming that the steep thermal gradients during quenching seed dense populations of microcracks that later explode into fracture networks under impact.

Microstructural investigation grounded these observations in chemistry and physics. X-ray diffraction of specimens heated to 800 degrees showed the disappearance of calcium hydroxide peaks and weakened calcium carbonate signals, evidence that these phases had thermally decomposed—reactions that release vapor, increase porosity, and weaken the matrix. Scanning electron microscopy revealed the deterioration in vivid detail: an unheated specimen showed a dense microstructure with abundant calcium-silicate-hydrate gel and a compact interfacial transition zone around each aggregate, while specimens heated to 800 degrees contained no detectable C-S-H gel at all, their structure riddled with pores and cracks and hosting instead a dicalcium silicate-like phase. Comparing cooling regimes at 400 degrees, the naturally cooled sample remained relatively dense and rich in hydration products, whereas its water-quenched twin displayed obvious cracks at the interfacial transition zone and a loosened surrounding matrix—the fingerprint of thermal shock stress racing through the cooling material.

The practical implications reach well beyond the laboratory. Tunnel linings that survive a fire are routinely assessed and, if necessary, repaired, but this study shows that the assessment itself must account for the cooling history. A lining quenched by firefighting water may be significantly weaker than its peak temperature alone would suggest, particularly if it subsequently faces dynamic loads from traffic vibration, rockfall impacts, or secondary events. Conversely, the results give engineers a positive tool: specifying basalt fiber reinforcement at around 0.2 percent by volume can meaningfully bolster the impact resistance of fire-exposed concrete below 600 degrees, at a modest material cost. The authors frame their work as a theoretical foundation for post-fire safety assessment of tunnel linings and for the wider engineering adoption of basalt fiber-reinforced concrete—a reminder that in structural fire engineering, what happens in the minutes after the flames matter almost as much as the fire itself.

At Earth’s poles, much of the heat leaving the planet is invisible to human eyes. NASA’s two PREFIRE CubeSats are measuring that far-infrared energy directly, and a new animation built from two complete seasonal cycles shows just how differently the Arctic and Antarctic warm and cool. The Polar Radiant Energy in the Far-InfraRed Experiment began […]

The post NASA’s PREFIRE Satellites Show How the Poles Trade Heat With Space appeared first on Curiosmos.

The wildfires afflicting communities across the world can now be tracked more easily by anyone using Europe’s free and open satellite imagery service—all thanks to a wildfire visualization script originating from nearly a decade ago.

The Copernicus Browser provides free access to the latest satellite imagery taken by the European Space Agency’s Sentinel satellites for the European Union’s Earth observation program. The three satellites of the Sentinel-2 mission have proven especially useful for wildfire monitoring by providing multi-spectral imaging at resolutions as granular as 10 meters in visible light and near-infrared bands—and the Copernicus Browser previously offered 10 default visualization layers using different combinations of spectral bands.

Now Copernicus Browser has also added a straightforward “wildfires” visualization layer for Sentinel-2 imagery that went live on August 4. Anyone clicking on this layer while looking at a wildfire location can see active fires in white or yellow, burning vegetation in red, and burned landscapes in dark brown or black.

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The wildfires afflicting communities across the world can now be tracked more easily by anyone using Europe’s free and open satellite imagery service—all thanks to a wildfire visualization script originating from nearly a decade ago.

The Copernicus Browser provides free access to the latest satellite imagery taken by the European Space Agency’s Sentinel satellites for the European Union’s Earth observation program. The three satellites of the Sentinel-2 mission have proven especially useful for wildfire monitoring by providing multi-spectral imaging at resolutions as granular as 10 meters in visible light and near-infrared bands—and the Copernicus Browser previously offered 10 default visualization layers using different combinations of spectral bands.

Now Copernicus Browser has also added a straightforward “wildfires” visualization layer for Sentinel-2 imagery that went live on August 4. Anyone clicking on this layer while looking at a wildfire location can see active fires in white or yellow, burning vegetation in red, and burned landscapes in dark brown or black.

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The Chicxulub impact not only plunged Earth into an impact winter but also produced a dust blanket that later overheated the planet, according to new research from Purdue University and the University of Colorado, Boulder.

The post Dinosaur-Killing Asteroid Didn’t Just Strike Earth, Its Dust Cloud Cooked It appeared first on Sci.News: Breaking Science News.

A massive wildfire that scorched the Nevada desert near the U.S. Air Force’s classified Area 51 facility over the weekend has now exceeded 2,000 acres.

The fire, which began on Friday, continued spreading through Lincoln County, Nevada, according to officials with the U.S. Bureau of Land Management (BLM), one of the agencies working to control the blaze.

“This is a restricted area, closed to the public, always, regardless of fire activity,” BLM officials said in a statement, adding that there are presently no additional closures in effect in the area.

Dubbed the Quail Springs fire, crews continued battling against heavy smoke and flames within the Nevada Test and Training Range throughout the weekend.

One of two military training areas located within the Nellis Air Force Base Complex in Nevada, the classified site is home to a simulated Integrated Air Defense System (IADS) and features close to 1,200 targets and other military assets frequently used in training operations.

With its storied history involving the development and testing of some of America’s most secretive aircraft, Area 51 has long remained an item of public fascination. Presently, there is no indication that the fire could impact operations at the facility.

Additionally, while BLM officials say there are no residences or other structures currently being threatened, the fire reportedly still has zero containment, according to information available on the Nevada Wildfire Information Dashboard.

“Warm, dry weather with afternoon breezes is expected through Tuesday,” read a portion of a statement that appeared on the BLM website. “Fire activity is expected to increase during the afternoon burning period before moderating overnight as temperatures cool and humidity recovers.”

Presently, the BLM says there are no significant weather changes expected, although some isolated thunderstorms are possible in the area over the next several days. While the presence of moisture would seemingly be hoped for under such conditions, BLM officials said that such storms could also introduce “potentially gusty and erratic winds,” which may “contribute to fire spread.”

Lightning associated with such isolated storms is often a key trigger for such fires during the otherwise arid summer months. Presently, BLM officials believe a lightning strike had likely triggered this weekend’s fire, as well.

“The fire will continue to be monitored closely,” the BLM statement read.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.

A fast-moving wildfire, one of many raging across Spain, bore down on the Madrid Deep Space Communications Complex on Friday, forcing an evacuation and temporarily suspending operations at one of NASA's most important tracking stations.

The tracking station is part of NASA's Deep Space Network, operating in concert with similar facilities in California and Australia to provide global coverage as Earth's rotation brings the planets, stars, and deep space probes in and out of view. The network supports more than 40 missions from the Moon to the edge of the Solar System, including Artemis, the James Webb Space Telescope, and NASA's twin Voyager spacecraft.

A NASA spokesperson confirmed the tracking station in Spain, located in the hills nearly 40 miles (65 kilometers) west of central Madrid, was evaluated Friday "due to ongoing wildfires in the region. Photos and video from the area showed flames and smoke plumes rising over the ground station's antenna array, anchored by a 230-foot-diameter (70-meter) radio dish and a collection of smaller 112-foot (34-meter) antennas.

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A 201-million-year-old climate catastrophe turned Europe into a landscape of fern savannahs that repeatedly caught fire, according to new research published in the journal Nature Geoscience.

The post Fern-Fueled Wildfires Raged across Europe for Millennia during End-Triassic Mass Extinction appeared first on Sci.News: Breaking Science News.

Scientists have uncovered compelling new evidence that early human ancestors, likely Homo erectus, were deliberately bringing fire into Wonderwerk Cave in South Africa as far back as 1.79 million years ago.

The post Evidence of Fire Use by Early Humans May Date Back Nearly 1.8 Million Years appeared first on Sci.News: Breaking Science News.

An international team of researchers led by Dr. Liora Kolska Horwitz of the Hebrew University of Jerusalem’s National Natural History Collections, working at the site of the oldest dated intentional use of fire by ancient human ancestors, South Africa’s Wonderwerk Cave, has found new evidence pushing that date even earlier into prehistory.

The research team behind the potentially history-altering findings said the discovery, which suggests that ancient hominins intentionally controlled fire, resulting in charred animal bones sometime between 1.07 and 1.79 million years ago, provides researchers with previously unavailable insights into how our ancestors first began to harness one of the most important tools in the evolution of human society and culture.

The study also introduced the archaeological community to a promising new method for analyzing burned bone samples by monitoring its light-emitting properties.

Intentional Use of Fire Provided Human Ancestors with a Critical Tool

According to a statement announcing the study, Dr. Horwitz, who is co-director of the Wonderwerk Cave project with Prof. Michael Chazan at the University of Toronto, and colleagues note the historical significance of fire, ranging from warmth and predator protection to extended daylight and the cooking of meat. However, historians have struggled to identify a single moment or historical period where humanity’s ancient ancestors first started to use fire intentionally.

“Evidence of fire from such ancient sites is often subtle and difficult to detect,” Dr. Horwitz explained.

Before the new analysis, the oldest agreed-upon evidence for intentional fire use also came from Wonderwerk Cave. Situated within the Kalahari Desert of South Africa, the cave provided evidence placing fire use to approximately 1 million years ago.

While that study used the most advanced techniques available, the team behind the new study decided to employ a non-invasive process that involves illuminating ancient bone fragments with specific wavelengths of light to determine whether they had been exposed to intense heat. In cases where bones have been heated to fire-like temperatures, the right wavelength of light will cause them to glow.

Remains Likely Left by Homo Erectus

Because evidence from ancient sites is scarce, the team’s non-invasive technique allowed them to study tiny fossilized rodent bones left in the cave by owls without damaging them. The team noted that using remains that accumulated naturally on the ancient cave floor provides an “independent, non-anthropogenic record” of ancient events within the local area.

After exposing the ancient bone to specific wavelengths of light, the team found what they described as “clear signs of burning.” Dr. Horowitz confirmed the findings, noting that the team’s analysis reveals “fire was repeatedly present deep inside Wonderwerk Cave.”

Because the deposits were found over 30 meters deep in the cave, the team ruled out wildfires as a possible source of combustion. The layer also lacked bat guano remains, which the team noted “rules out spontaneous combustion.”

A chemical analysis of the charred bones dated them to between 1.07 and 1.79 million years ago, redating the 2012 findings. Critically, the evidence for ancient fire use was in an archaeological layer “associated with artifacts” from the initial Acheulean period, which is consistent with the dating. If correct, this would make the likeliest early human ancestor that used fire Homo erectus.

Although the findings appear to extend the chronology of one of the earliest known records of fire use associated with hominins by as much as 790,000 years, the research team said the findings do not suggest that these early proto-humans could create fire “at will.” Instead, the likeliest scenario involves early human ancestors collecting fire from natural sources, such as lightning-induced wildfires on the African savanna, and bringing it into the cave.

“The early humans introduced this fire into the cave on multiple occasions and maintained it there before it eventually died out,” the team’s statement explained.

The team did not immediately pinpoint what methods these early hominins used to maintain a burning fire. However, they suggested that burning owl pellets as additional fuel may inadvertently have scorched the rodent bones.

A New Tool for Identifying Traces of Burning

When discussing the implications of the new, earlier date for the first intentional use of fire, Dr. Horwitz said the discovery shows that early human ancestors “were not simply passive observers of natural fires,” but instead were “actively engaging with fire and incorporating it into their lives.”

Beyond offering an earlier date range for early fire use, the work provides clues into how our ancestors used fire before they could make it on their own. The study also debuted a new, non-invasive, portable tool for investigating early fire use, which the study authors note “can be applied to large collections of fossils without damaging them.”

“Our study provides new tools for identifying traces of ancient burning,” Dr. Horwitz explained, with the team adding that application of this new technique to sites around the world “may help clarify the origins and development of one of the most consequential technologies in human history.”

The study “New evidence for Early Pleistocene use of fire at Wonderwerk Cave (South Africa)” was published in PLOS One.

Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.

The cycle of life and death in nature extends far beyond what meets the eye, with deceased organisms playing crucial roles in shaping the fate of entire ecosystems long after they’ve perished. While the sight of mushrooms sprouting from fallen logs or insects colonizing dead trees is familiar to many nature observers, new research reveals that this phenomenon operates on a much grander scale than previously understood.

Scientists have discovered that when “foundation species” – the cornerstone plants and animals that provide structure and resources for entire ecological communities – die, their remains continue to exert powerful influence over the survival and prosperity of other organisms. These dead giants don’t simply disappear; instead, they become environmental architects, creating new habitats and resource opportunities that can sustain diverse communities for years or even decades.

The research highlights how a single fallen tree can transform into a bustling metropolis of life, hosting everything from decomposer fungi to predatory beetles, each playing their part in an intricate web of interactions. This “afterlife ecology” demonstrates that death in nature isn’t an ending but rather a transformation – dead wood becomes nursery habitat, decaying leaves enrich soil chemistry, and empty shells provide shelter for new inhabitants.

Understanding these post-mortem ecological relationships is becoming increasingly important as climate change and habitat destruction threaten foundation species worldwide. When these keystone organisms disappear, their ecological influence continues, but the loss of new recruitment means ecosystems may face long-term structural changes that ripple through entire food webs.

The post How Dead Trees and Plants Continue to Shape Thriving Ecosystems After Death first appeared on EnviroLink Network.