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Many rocky planets from beyond our solar system glow with volcanic scars, yet their crusts sit frozen in place, locked together like a single giant shield. Is it possible that these planets host conditions that would be friendly to life?



<a href="https://planets.stanford.edu/people/matthew-reinhold" target="_blank" rel="noreferrer noopener">Matthew Reinhold</a>, a doctoral researcher, and <a href="https://sustainability.stanford.edu/people/laura-schaefer" target="_blank" rel="noreferrer noopener">Laura Schaefer</a>, an assistant professor at Stanford University, created detailed computer models showing that such static‑crust planets, which they call Ignan Earths, can still nurture liquid water, mild air, and potentially thriving ecosystems.



<h2 class="wp-block-heading" id="h-planets-need-to-lose-heat">Planets need to lose heat</h2>



Earth regulates temperature partly through <a href="https://pubs.usgs.gov/gip/dynamic/inside.html" target="_blank" rel="noreferrer noopener">plate tectonics</a>. This involves the slow rafting of rigid lithospheric slabs over the mobile asthenosphere, a motion driven by <a href="https://www.earth.com/news/earths-mantle-chemistry-has-remained-stable-for-billions-of-years/">mantle convection</a>. 



Moving plates recycle carbon, build mountains, open ocean basins, and refresh the seafloor, continually giving life new niches and chemical feedstocks.



Without that conveyor belt, heat must still escape, or a planet risks turning into a pressure‑cooked Io where lava fountains blanket the ground. 



<a href="https://www.earth.com/news/microbial-life-may-exist-on-one-of-jupiters-moons/">Jupiter’s</a> volcanic moon, <a href="https://science.nasa.gov/jupiter/jupiter-moons/io/">Io</a>, loses roughly 1.5 watts of heat per square yard, about twenty times Earth’s average output.



Reinhold and Schaefer explored planetary interiors that pump out between 1 and 15 watts per square yard. This is well below Io’s extreme, yet well above <a href="https://www.earth.com/news/scientists-simulate-what-the-first-days-of-early-earth-were-really-like-after-it-formed/">Earth</a>’s gentle glow.



<h2 class="wp-block-heading" id="h-ignan-earths-may-favor-life">Ignan Earths may favor life</h2>



Their models indicate that the <a href="https://www.earth.com/news/how-earths-mantle-shapes-surface-topography/">mantle</a> of an Ignan Earth remains mostly solid, so globe‑spanning lava oceans are not inevitable or even likely. 



Instead, on these <a href="https://searchworks.stanford.edu/view/jt673zb0893" target="_blank" rel="noreferrer noopener">types of planets</a>, magma threads upward through narrow conduits in a process called heat‑pipe tectonics. The process carries energy and gases to the surface while leaving the crust largely intact.



Surprisingly, simulated surface temperatures stayed under 185°F (85°C), even when interior heat rose an order of magnitude above Earth’s. 



Efficient atmospheric feedbacks kept the climate within a stable range by balancing volcanic outgassing with rapid chemical weathering.



That range overlaps the “<a href="https://www.researchgate.net/publication/259264907_A_cool_early_Earth" target="_blank" rel="noreferrer noopener">cool early Earth</a>” window revealed by 4.4 billion‑year‑old zircons. This evidence points to liquid seas and temperate air long before modern continents formed and photosynthesis began.



In other words, a fiery heart does not doom a planet to lifelessness. It may mimic the balmy warmth that our own world enjoyed while life gained its first biochemical foothold.



<h2 class="wp-block-heading" id="h-internal-heating-on-ignan-earths">Internal heating on Ignan Earths</h2>



Heat‑pipe tectonics vents gases continually, replacing the sporadic eruptions that are familiar on a plate‑bearing world with a ceaseless planetary simmer. 



The researchers’ simulations show <a href="https://www.earth.com/news/webb-captures-first-direct-image-of-co2-outside-our-solar-system-hr-8799/">carbon dioxide</a> bubbling out through thousands of mini‑volcanoes, yet rainfall and rock weathering lock much of that gas away within newly formed basalts.



That exchange forms a vertical version of the <a href="https://personal.ems.psu.edu/~jfk4/PersonalPage/ResInt2.htm" target="_blank" rel="noreferrer noopener">carbonate‑silicate cycle</a>, a global thermostat that balances greenhouse warming against chemical drawdown, and keeps oceans from evaporating.



“We find that Earth‑mass planets with internal heating fluxes below 15 W m⁻² produce average surface temperatures that Earth has experienced in its past, below 30°C (86°F),” noted Reinhold. 



At higher heat loads, the thermostat still holds, never pushing oceans to a boil or stripping a planet of habitability.



<h2 class="wp-block-heading" id="h-feedbacks-keep-climate-friendly-for-life">Feedbacks keep climate friendly for life</h2>



Atmospheric models linked to the interior calculations revealed negative feedbacks almost identical to those on Earth, despite the lack of sliding plates. 



As volcanic outgassing raises carbon dioxide levels, weathering rates accelerate, scrubbing the air and lowering temperatures until equilibrium returns.



If a planet edges toward the <a href="https://arxiv.org/abs/2505.11149" target="_blank" rel="noreferrer noopener">runaway greenhouse limit</a>, added heat expands the atmosphere, thickening cloud decks that bounce sunlight back into space and slow further warming. 



The team’s hottest test cases stayed safely below one‑twentieth of that threshold, keeping average seas from surpassing 212°F (100°C), a conservative benchmark for surface sterilization.



Even tidal heating scenarios, such as a planet locked in a close dance with a <a href="https://www.earth.com/news/planets-orbiting-red-dwarf-stars-may-not-be-habitable-ultraviolet-uv-radiation/">red dwarf</a>, left room for clement oceans and long‑term climate stability. 



This suggests that synchronous rotation and internal heat from tidal forces don’t automatically preclude a planet from hosting life-friendly environments.



<h2 class="wp-block-heading" id="h-why-ignan-earths-matter">Why Ignan Earths matter</h2>



Almost one‑third of rocky exoplanets discovered so far orbit stars in zones where tidal forces or radioactivity can supercharge their interiors, producing heat budgets similar to those on Ignan Earths. 



Traditional habitability filters often dismissed these planets, assuming static lids meant sterile magma deserts with no recycling of nutrients.



The Stanford study widens the pool of targets for observatories like JWST, ELT, and the upcoming <a href="https://science.nasa.gov/astrophysics/programs/habitable-worlds-observatory/" target="_blank" rel="noreferrer noopener">Habitable Worlds Observatory</a>, all of which can sniff atmospheric chemistry from light‑years away. 



Future spectra that catch volcanic gases alongside water vapor could hint at continents weathering out of fresh basalt. This would potentially signal vertical recycling that distinguishes Ignan Earths from stagnant, Venus‑like planets.



If Ignan Earths prove common, they may resemble our <a href="https://www.earth.com/news/astronomers-announce-evidence-suggesting-that-our-solar-system-has-nine-planets-again/">planet</a> during the Hadean, when a young Sun shone dimmer yet internal fires burned brighter and chemistry set the stage for biology. 



Such parallels could mean that life on planets elsewhere begins not in calm, stable conditions but in heat-driven chaos that gradually cools into habitability.



The study is published in the <a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023JE008029" target="_blank" rel="noreferrer noopener">Journal of Geophysical Research: Planets</a>.



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Scientists find rocky planets that appear inhospitable, but discover they could harbor life

Many rocky planets from beyond our solar system glow with...

Eighty‑three years after a torpedo tore it away, the 150‑foot steel bow of USS New Orleans reappeared, this time as pixels on sonar and video, sitting about 2,215 feet down in the <a href="https://oceanexplorer.noaa.gov/news/oer-updates/2025/iron-bottom-sound.html" target="_blank" rel="noreferrer noopener">Solomon Islands’ Iron Bottom Sound.</a>



The heavy cruiser lost nearly one‑third of her hull and 182 sailors during the November 1942 <a href="https://www.history.navy.mil/browse-by-topic/wars-conflicts-and-operations/world-war-ii/1942/guadalcanal/battle-of-tassafaronga.html" target="_blank" rel="noreferrer noopener">Battle of Tassafaronga</a>, yet damage‑control teams braced the jagged wound with coconut logs and steered the ship home in reverse to Puget Sound for <a href="https://www.earth.com/news/giant-copper-deposits-in-tibet-are-fueled-by-an-ancient-tectonic-collision/">repairs</a>.



<h2 class="wp-block-heading" id="h-a-bow-lost-for-eight-decades">A bow lost for eight decades</h2>



“This imagery was viewed in real time by hundreds of experts around the world, who all worked together to make a positive identification of the findings. The discovery highlights the power of having multiple scientists and <a href="https://www.earth.com/news/archaeologists-find-hallucinogenic-seeds-in-ancient-bones-black-henbane/">technologies</a> work together to achieve a common goal,” said <a href="https://nautiluslive.org/people/daniel-wagner" target="_blank" rel="noreferrer noopener">Daniel Wagner</a>, chief scientist with <a href="https://nautiluslive.org/" target="_blank" rel="noreferrer noopener">Ocean Exploration Trust</a>.



“By all rights, this ship should have sunk,” retired <a href="https://www.history.navy.mil/about-us/leadership/director.html" target="_blank" rel="noreferrer noopener">Rear Admiral Samuel J. Cox</a>. Japanese “<a href="https://www.usni.org/magazines/naval-history-magazine/2019/april/massive-torpedo" target="_blank" rel="noreferrer noopener">Long Lance</a>” torpedoes struck after midnight, detonating forward magazines and shearing off turrets one and two.



With steering gone and compartments flooding, electricians jury‑rigged power, sailors shoved timber through shattered frames, and the crippled vessel crawled into <a href="https://www.tracesofwar.com/sights/127930/Tulagi-Harbor.htm" target="_blank" rel="noreferrer noopener">Tulagi Harbor</a> before the makeshift bow fell apart.



<h2 class="wp-block-heading" id="h-uss-new-orleans-wreck-site">USS New Orleans wreck site</h2>



Five night battles raged here between August and December 1942, claiming 20,000 lives, 111 naval vessels, and 1,450 aircraft from Allied and Japanese forces.



Most wrecks rest inside a corridor only 25 nautical miles wide, turning the sound into a condensed <a href="https://www.deeperblue.com/lost-bow-of-uss-new-orleans-found-in-depths-of-iron-bottom-sound/" target="_blank" rel="noreferrer noopener">graveyard</a> of steel and sacrifice.



So far just 30 of those wartime hulks have been located, leaving dozens more for future surveys and the families who still wait for closure.



<h2 class="wp-block-heading" id="h-how-robots-share-the-workload">How robots share the workload</h2>



Discovery began with <a href="https://nautiluslive.org/tech/usv-drix" target="_blank" rel="noreferrer noopener">USV DriX</a>, a 25‑foot uncrewed surface vessel developed by <a href="https://www.exail.com/" target="_blank" rel="noreferrer noopener">Exail</a> and operated by the <a href="https://www.unh.edu/" target="_blank" rel="noreferrer noopener">University of New Hampshire</a>.



Running pre‑programmed lawn‑mower lines, DriX beamed high‑resolution seafloor mosaics back to <a href="https://nautiluslive.org/tech/ev-nautilus" target="_blank" rel="noreferrer noopener">E/V Nautilus</a>, where pilots dispatched Hercules, a tethered remote‑operated vehicle, to inspect an intriguing 150‑foot shadow the sonar had painted.



“NOAA Ocean Exploration’s mission is to explore the ocean for America’s benefit,” said <a href="https://gulfcoast23.oceansconference.org/bill-mowitt/" target="_blank" rel="noreferrer noopener">Captain William Mowitt</a>, acting director of <a href="https://oceanexplorer.noaa.gov/" target="_blank" rel="noreferrer noopener">NOAA Ocean Exploration</a>, adding that pairing DriX with deep‑diving ROVs “has the potential to reshape our understanding of what lies in the deep ocean.”



<h2 class="wp-block-heading" id="h-inside-the-drix-toolbox">Inside the drix toolbox</h2>



A carbon‑Kevlar composite hull lets the craft slice waves at 13 knots while weighing only 1.4 tons, light enough for a single point lift.



Seven‑day endurance at 7 knots means the boat can map while the crew sleeps, delivering coverage impossible for a conventional ship and burning a fraction of the fuel.



Twin <a href="https://geo-matching.com/products/em-712-2-x-2-degree-multibeam-echo-sounder" target="_blank" rel="noreferrer noopener">EM‑712</a> and <a href="https://www.kongsberg.com/discovery/seafloor-mapping/em/EM2040-Mk2/" target="_blank" rel="noreferrer noopener">EM‑2040</a> multibeam sonar units sweep frequencies from 40 kHz to 400 kHz, detailing contours from tidal flats out to 1,600 feet, while an <a href="https://www.fisheries.noaa.gov/west-coast/science-data/ek80-adaptive-logger" target="_blank" rel="noreferrer noopener">EK‑80 fisheries</a> echosounder tracks mid‑water life that often crowds wreck sites.



Real‑time kinematic GPS, lidar, and long‑range marine broadband radios stitch the <a href="https://www.earth.com/news/ancient-mantle-plume-created-a-60-million-year-volcanic-trail-from-iceland-to-ireland/">surface</a> plot to ROV video, so historians can consult, annotate, and archive images as they stream ashore.



The team’s approach, pairing autonomous surface vessels like DriX with real-time feedback from ROVs, could be applied to other unexplored maritime graveyards around the world.



From the Arctic to the <a href="https://coral.org/en/where-we-work/coral-triangle/" target="_blank" rel="noreferrer noopener">Coral Triangle</a>, wreck sites hold historical and ecological significance that often go unstudied because of depth, cost, or geopolitical sensitivity.



<h2 class="wp-block-heading" id="h-honoring-uss-new-orleans-crew">Honoring USS New Orleans crew</h2>



Cox called the find “an opportunity to remember the sacrifice of this valiant crew, even on one of the worst nights in U.S. Navy history,” underscoring that exploration is as much about people as hardware.



Telepresence let descendants in Louisiana, naval architects in Japan, and students in Australia witness the anchor still stamped “Navy Yard” on live video, knitting a dispersed community around a single rusted artifact.



Archaeologists photographed but did not disturb the site, treating it as a war grave and deep‑sea reef now colonized by <a href="https://www.earth.com/news/rocks-reveal-the-turning-point-when-oxygen-changed-earth-forever/">corals</a>, anemones, and basket stars.



<h2 class="wp-block-heading" id="h-more-wrecks-near-uss-new-orleans-nbsp">More wrecks near USS New Orleans&nbsp;</h2>



DriX will continue to grid the 1,400‑foot‑deep basins of Iron Bottom Sound through mid‑July, queuing new ROV dives for wrecks long rumored but never confirmed.



Each stitched mosaic whittles down the unknown, proving that small autonomous craft and human curiosity can retrieve lost chapters of history, one sonar ping at a time.



<h2 class="wp-block-heading" id="h-why-these-finds-still-matter">Why these finds still matter</h2>



Shipwrecks like USS New Orleans serve as underwater time capsules that link global history with modern identity. They’re not just remnants of war, they’re markers of engineering, courage, and diplomacy that shaped the present.



Their rediscovery helps nations reconcile with shared pasts, especially in regions like the South Pacific where legacy and loss are deeply intertwined. 



These missions renew collective memory and allow younger generations to engage with stories often left out of textbooks.



Click here to see more images of this <a href="https://nautiluslive.org/album/2025/07/08/first-photos-uss-new-orleans-bow-80-years" target="_blank" rel="noreferrer noopener">historic discovery of the USS New Orleans</a>.



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USS New Orleans bow found 83 years after it was sunk by a torpedo in World War II

Eighty‑three years after a torpedo tore it away, the 150‑foot...

Today's flagship processor packs more than 100 billion transistors, yet <a href="https://lab.semi.ac.cn/library/upload/files/2023/2/acf548c67ad377a9.pdf" target="_blank" rel="noreferrer noopener">squeezing</a> them any closer is turning design into a wrestling match with quantum physics. 



As the footprints of silicon switches approach the dimensions of a few dozen atoms, stray electrons tunnel across barriers that once looked rock‑solid, wasting power and scrambling <a href="https://www.earth.com/news/quantum-material-could-make-computers-1000-times-faster/">signals</a>.



Physicists are asking whether that unruly behavior can be steered instead of suppressed, and a new study from the University of California, Riverside (<a href="https://www.ucr.edu/" target="_blank" rel="noreferrer noopener">UCR</a>), claims the answer is yes. 



The team shows that by shaping atom‑perfect <a href="https://www.sciencedirect.com/topics/engineering/silicon-cluster" target="_blank" rel="noreferrer noopener">silicon clusters</a> they can turn electron flow off and on through <a href="https://quantum.microsoft.com/en-us/insights/education/concepts/interference" target="_blank" rel="noreferrer noopener">quantum interference</a>, the same wave effect that makes light cancel itself in noise‑canceling headphones.



<h2 class="wp-block-heading" id="h-how-silicon-molecule-switches-current">How silicon molecule switches current</h2>



<a href="https://teamsu.org/about-tim" target="_blank" rel="noreferrer noopener">Tim Su</a> of UC Riverside and colleagues built their switch by assembling silicon atoms into a molecule called <a href="https://www.science.org/doi/10.1126/science.1118981" target="_blank" rel="noreferrer noopener">sila‑adamantane</a>, a miniature copy of the crystal motif found in commercial chips.&nbsp;



“We found that when tiny silicon <a href="https://www.earth.com/news/schrodingers-cat-put-into-silicon-chip-may-be-holy-grail-for-error-proof-quantum-computing/">structures</a> are shaped with high symmetry, they can cancel out electron flow like noise‑canceling headphones,” said Su.



Aligning gold electrodes with the cage’s short branches lets the two electron waves reinforce one another, raising conductance, while contacting the long branches flips the phase and wipes the current out. The measured on–off ratio averages 5.6, rivaling single‑molecule devices built from <a href="https://frontierspecialtychemicals.com/product-category/porphyrins/?srsltid=AfmBOoravB_JvFtNx_jSvUG1FmsYvNKAQjNrdqclAEHDXcT2L5e64jzw" target="_blank" rel="noreferrer noopener">exotic porphyrins</a>.



<h2 class="wp-block-heading" id="h-smaller-chips-don-t-work-as-well">Smaller chips don't work as well</h2>



Conventional scaling relies on etching <a href="https://lab.semi.ac.cn/library/upload/files/2023/2/acf548c67ad377a9.pdf" target="_blank" rel="noreferrer noopener">ever‑narrower channels</a> and then doping them with other atoms so voltage can police the charge carriers. 



Once those channels dip below about five nanometers, electrons act less like marbles and more like waves, slipping through the gate oxide by tunneling and driving leakage to costly levels.



<a href="https://resources.system-analysis.cadence.com/3d-electromagnetic/msa2021-the-constructional-and-dimensional-details-of-finfets" target="_blank" rel="noreferrer noopener">Three‑dimensional FinFETs</a> and gate‑all‑around stacks help but still fall victim to quantum leakage once dimensions hit the atomic wall. 



That stalemate pushes designers toward switches that exploit interference rather than brute electrostatics, trading geometry for wave control.



<h2 class="wp-block-heading" id="h-silicon-switches-atom-by-atom">Silicon switches, atom by atom</h2>



Instead of carving bulk wafers with ultraviolet light, the Riverside team used classical synthetic chemistry to snap <a href="https://www.nature.com/articles/s41467-020-17815-z" target="_blank" rel="noreferrer noopener">silicon-silicon bonds</a> into the exact three‑dimensional orientation prescribed by their design. 



Bottom‑up growth means every device is born identical, a sharp contrast to <a href="https://www.columbiamuseum.org/news/lithography-its-process" target="_blank" rel="noreferrer noopener">lithography</a> at atomic limits, where dropping a single atom can make neighboring transistors behave like strangers.



The cluster’s perfect C3 symmetry proved crucial. When electrodes were anti‑aligned with the long cage branches, destructive interference slashed conductance nearly threefold relative to a trimmed control structure that lacked one silicon link.



Flipping to the short path realigned the wave phases and restored current, creating a mechanically tunable <a href="https://www.earth.com/news/quantum-computing-giant-leap-forward-breakthrough-ultra-pure-silicon-discovery/">molecular switch</a>. 



The low torsional barrier of the attached linkers means a modest stretch can toggle the molecule between off and on states like a lever.



<h2 class="wp-block-heading" id="h-silicon-switch-turns-heat-into-usable-energy">Silicon switch turns heat into usable energy</h2>



The same interference physics could also sharpen silicon‑based <a href="https://www.sciencedirect.com/science/article/pii/S2542529324001287" target="_blank" rel="noreferrer noopener">thermoelectric generators</a> that tap temperature gradients for power. 



Porous silicon <a href="https://www.inredox.com/technology/si-nanowires/" target="_blank" rel="noreferrer noopener">nanowire arrays</a> have already shown higher efficiency than any previous nanostructured silicon thermoelectric at 801°F, according to a 2024 <a href="https://www.energy.ca.gov/publications/2024/low-cost-high-reliability-thermoelectrics-waste-heat-conversion" target="_blank" rel="noreferrer noopener">report</a> for the <a href="https://www.energy.ca.gov/" target="_blank" rel="noreferrer noopener">California Energy Commission</a>.



Bulk silicon once posted a meager figure of merit near 0.01, yet early nanowire <a href="https://spectrum.ieee.org/silicon-nanowires-turn-heat-to-electricity" target="_blank" rel="noreferrer noopener">experiments</a> boosted that number up to 0.6, roughly matching <a href="https://www.earth.com/news/new-microscopic-mineral-ehrigite-discovered-could-revolutionize-geological-exploration/">bismuth telluride</a>, the industry’s workhorse material. 



Berkeley Lab’s porous carpets have since multiplied the figure of merit eighteenfold, suggesting that interference‑tuned carrier paths could raise it even further by trimming parasitic heat flow.



A switchable junction between hot and cold ends could throttle charge flow on the fly, matching output to load conditions without external electronics. 



That adaptive behavior is attractive for industrial waste‑heat recovery, where temperatures and demand vary minute by minute.



<h2 class="wp-block-heading" id="h-uses-in-memory-and-quantum-tech">Uses in memory and quantum tech</h2>



Because the molecule mimics the lattice that hosts spin‑based qubits, symmetry‑controlled interference may serve future <a href="https://www.earth.com/news/quantum-teleportation-communication-achieved-on-regular-internet-cables/">quantum‑information</a> hardware. 



In principle, the same silicon cage could ferry spin or valley states protected from decoherence by the selection rules that make interference possible, dodging many of the troubles that plague superconducting circuits.



Industry can test the chemistry inside familiar clean‑room lines, because the cluster is built from the element fabs already master. 



A cross‑bar memory woven from such switches would store data at densities far beyond what FinFETs allow, without rewriting fabrication playbooks from scratch.



<h2 class="wp-block-heading" id="h-scaling-silicon-switches">Scaling silicon switches</h2>



<a href="https://teamsu.org/">Su’s lab</a> is already tweaking the cage with different linkers to raise the on-off ratio and studying whether flexible leads can turn the molecule into a piezoresistive sensor that toggles under strain. 



Colleagues in device physics are evaluating whether the molecule’s switching noise stays low enough for logic thresholds at room temperature.



The bigger challenge lies in wiring billions of identical silicon clusters onto substrates while preserving their three‑dimensional orientation. 



Directed self‑assembly and DNA‑templated placement are among the approaches on the table, and progress there will decide whether molecular interference moves from the benchtop to production.



The study is published in the <a href="https://pubs.acs.org/doi/10.1021/jacs.5c04272" target="_blank" rel="noreferrer noopener">Journal of the American Chemical Society</a>.



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Physicists learn to control electricity at the quantum scale

Today's flagship processor packs more than 100 billion transistors, yet...

For decades, reptiles - including tortoises - have lingered in the background of animal sentience discussions. Popular imagination often casts them as simple, instinct-driven beings - unfeeling and unaware. 



Unlike mammals and birds, they rarely show overt emotion, leading many to dismiss the idea that reptiles might feel in complex ways. 



But a new study from the <a href="https://www.lincoln.ac.uk" target="_blank" rel="noreferrer noopener">University of Lincoln</a> has disrupted that belief, offering compelling evidence that red-footed tortoises (Chelonoidis carbonaria) can experience long-term mood states.



Published in the journal Animal Cognition, the study reveals that tortoises can show optimism and pessimism depending on their environment. These emotional states then shapes their response to the world around them.



The implications are profound. If tortoises can feel mood shifts similar to mammals and birds, we must rethink how they are treated in captivity and reconsider their place in the story of animal consciousness.



<h2 class="wp-block-heading" id="h-what-moods-mean-in-animals">What moods mean in animals</h2>



Mood and emotion are not the same. Emotions are short-lived responses to immediate situations, like fear when chased or joy at finding food. Moods, on the other hand, linger. 



They form a kind of emotional background noise, influencing how an animal perceives new experiences. Scientists call these “free-floating” states, unattached to specific triggers but powerful in shaping behavior.



In humans and other mammals, we have tested mood using cognitive bias tasks. These tests explore how an individual interprets ambiguous situations. 



Someone in a good mood will expect a positive outcome, while someone in a bad mood will expect the worst. Until now, no study had used this method on <a href="https://www.earth.com/news/turtles-may-hold-the-secret-to-cancer-prevention/">reptiles</a>.



That gap has finally been closed. Researchers at Lincoln tested 15 red-footed tortoises to determine if they could exhibit mood-driven bias. Their approach was clear and controlled, building on established methods from mammal studies.



<h2 class="wp-block-heading" id="h-tortoises-respond-to-uncertainty">Tortoises respond to uncertainty</h2>



Each <a href="https://www.earth.com/news/turtle-heads-reveal-an-ancient-reptilian-secret/">tortoise</a> was trained in a simple spatial judgment task. A bowl placed in one spot always contained a food reward (rocket leaves). 



The same bowl, placed elsewhere, never had food. Once trained, tortoises were presented with the bowl at three new, in-between locations: one near the positive spot, one in the middle, and one near the negative.



How quickly a tortoise approached the bowl at each of these ambiguous points showed its expectation. Quick approach meant optimism. Hesitation meant doubt or pessimism. 



Every trial was carefully timed, filmed, and structured to avoid smell-based cues or random behavior. The test was fair.



Interestingly, the tortoises judged the near-positive and middle spots more optimistically. They moved faster toward these bowls, showing an “optimistic skew” similar to that seen in mammals and birds. This alone is a strong sign of mood in action. 



<h2 class="wp-block-heading" id="h-anxiety-measured-in-action">Anxiety measured in action</h2>



To confirm that mood shaped behavior beyond just one task, the tortoises were also subjected to two classic <a href="https://www.earth.com/news/where-do-fear-and-anxiety-reside-in-the-brain-new-cells-identified/">anxiety</a> tests: the novel object test and the novel environment test. 



These are used widely in animal cognition to assess emotional reactions to unfamiliar situations.



In the novel object test, each tortoise encountered an unusual item, a colorful bead coaster, inside a familiar arena. 



The researchers recorded how long it took the tortoise to approach the object, how far it extended its head, and how quickly it began to move. Confident, relaxed tortoises moved sooner and extended their heads farther.



<h2 class="wp-block-heading" id="h-tortoise-mood-affects-behavior">Tortoise mood affects behavior </h2>



The novel environment test changed the tortoises’ surroundings. Different textures, colors, and patterns created a new sensory world. 



Again, tortoises were watched for how they responded to unfamiliarity. The researchers noted that tortoises who showed optimistic bias in the earlier task also behaved with more confidence in these settings.



For example, tortoises that approached ambiguous bowls faster also reached new objects more quickly. 



Some even extended their heads farther in strange environments, indicating comfort and curiosity. These behavioral links show a deep connection between mood and action.



<h2 class="wp-block-heading" id="h-rethinking-reptile-feelings">Rethinking reptile feelings</h2>



The authors of the study interpret these results as remarkable. The presence of a mood state in a tortoise means that reptiles do not simply react. They evaluate, anticipate, and feel. That changes the ethical landscape.



"Animal welfare concerns are reliant upon evidence that a given <a href="https://www.earth.com/news/world-turtle-day-protecting-turtles-tortoises-and-their-vanishing-habitats/">species</a> has the capacity to experience affective states," said Anna Wilkinson, a professor of Animal Cognition at the University of Lincoln. 



"With reptiles becoming increasingly common as pets, it is essential for us to study their moods and emotions to try to understand how captivity may impact them."



Professor Oliver Burman noted that the research represents a significant shift in our understanding of what reptiles can experience, with important implications for how we care for these animals in captivity and interact with them in the wild.



The researchers emphasized that these findings align reptiles more closely with mammals and birds in terms of emotional capacity.



While reptiles may lack certain emotional expressions seen in other animals, they still experience shifts in affective state. Their moods impact how they explore, respond, and behave.



<h2 class="wp-block-heading" id="h-tortoise-mood-and-the-roots-of-emotions">Tortoise mood and the roots of emotions</h2>



Reptiles diverged from mammals and birds hundreds of millions of years ago. That makes this discovery even more significant. If a tortoise, members of one of the oldest lineages of land animals, can experience mood, then the evolutionary roots of emotion run deeper than we thought.



The study references earlier research that found reptiles do show some emotional behavior, such as emotional fever and response to enrichment. 



But until now, no one had shown that they could experience long-lasting, mood-like states. These new results argue against the idea that reptiles have a narrow emotional spectrum.



They suggest that affective states, both emotional and mood-based, might be ancient features of vertebrate brains. These are not recent innovations. This insight matters for biology, psychology, and ethics.



<h2 class="wp-block-heading" id="h-reptiles-need-more-than-basics">Reptiles need more than basics</h2>



The researchers argue for major changes in how we house and care for reptiles. Current enclosures often focus on physical health and basic habitat needs. 



But if tortoises have moods, then their emotional well-being must also be addressed. That means offering larger enclosures, complex terrain, opportunities for exploration, and <a href="https://www.earth.com/news/brain-stimulation-could-change-the-future-of-math-education/">mental stimulation</a>.



According to the researchers, we should assume that they are not only capable of suffering but also experiencing enduring positive moods. Captive reptiles deserve spaces that support both.



The research also expands the toolkit for welfare assessments. Behavioral and mood-based testing can help zookeepers, researchers, and pet owners recognize when a reptile like a tortoise is distressed or thriving.



<h2 class="wp-block-heading" id="h-rethinking-how-we-see-tortoises">Rethinking how we see tortoises</h2>



For too long, tortoises have been treated as slow-moving curiosities. But this new evidence invites us to see them differently. They can be optimistic, feel anxiety, and might even experience contentment.



This is not just about red-footed tortoises. It is about revising our relationship with all <a href="https://www.earth.com/news/reptile-ancestors-appeared-40-million-years-earlier-than-we-thought/">reptiles</a>. The cold-blooded no longer seem cold-hearted. They are thinking, feeling beings. And now we have the science to prove it.



The study is published in the journal <a href="https://link.springer.com/article/10.1007/s10071-025-01973-y" target="_blank" rel="noreferrer noopener">Animal Cognition</a>.



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Grumpy tortoise? Reptiles can experience mood swings too

For decades, reptiles - including tortoises - have lingered in...

Greenland’s ice-covered landscape looks like an immovable block on satellite maps. Yet the story locked beneath its center suggests a very different past, one that places future coastal cities in a tight spot. 



During the <a href="https://www.sciencedirect.com/topics/social-sciences/pleistocene">Pleistocene</a> - the geologic chapter that began about 2.7 million years ago and ran through innumerable swings between cold and mild - the island’s ice waxed and waned in tune with global climate.



New evidence hints that those swings were more dramatic than scientists once believed.



In&nbsp;1993, drillers hauled a two‑mile‑deep ice core up from the island’s highest point and stowed the entire column in a Colorado freezer. 



The surprise awaited in the bottom three inches of sediment: perfectly preserved traces of a tundra ecosystem. 



That sliver of soil, shielded for ages by roughly 1.9 miles (3 km) of ice, now refocuses the conversation about <a href="https://www.earth.com/news/how-much-did-sea-levels-rise-after-the-last-ice-age-alarming-new-clues-revealed/">future sea level</a> and the stability of polar ice in a warming world.



<h2 class="wp-block-heading" id="h-tundra-hidden-beneath-greenland-s-ice">Tundra hidden beneath Greenland's ice</h2>



Once the drill broke through that 1.9‑mile roof of ice, the researchers retrieved those three inches of till. 



“These fossils are beautiful,” says Paul&nbsp;Bierman, a scientist at the <a href="https://www.uvm.edu/" target="_blank" rel="noreferrer noopener">University of Vermont</a> who co‑led the new study with UVM graduate student Halley&nbsp;Mastro and nine other researchers.



“But, yes, we go from bad to worse,” Bierman added, referring to what this finding implies about the impact of <a href="https://www.earth.com/news/indisputable-evidence-of-human-caused-climate-change/" target="_blank" rel="noreferrer noopener">human‑caused climate change</a> on melting of the Greenland ice sheet.



The till holds poppy, spike‑moss, woody willow tissue, fungal sclerotia, insect parts, and a band of soil capped by about&nbsp;16&nbsp;inches of erratic boulders. 



This is clear evidence that <a href="https://www.earth.com/news/drones-reveal-hidden-details-about-greenlands-melting-ice/" target="_blank" rel="noreferrer noopener">central Greenland</a> once lay ice‑free under a cold, dry sky where late‑lying snow lingered through early summer.



Because the material sits undisturbed, the team is confident it was not swept in from elsewhere as ice advanced.



<h2 class="wp-block-heading" id="h-inside-a-deep-greenland-ice-core">Inside a deep Greenland ice core</h2>



“Once we made the discovery at Camp&nbsp;Century, we thought, ‘Hey, what's at the bottom of&nbsp;GISP2?’” Bierman recalled.



High‑energy isotope ratios show that the summit last saw open air within the past 1.1 million years, while argon trapped in overlying clear ice indicates at least 250,000 years of continuous cover since then. 



<a href="https://www.nature.com/articles/s41467-024-47351-z" target="_blank" rel="noreferrer noopener">Basal ice</a> at another drilling site about 19 miles away is roughly 1 million years old.



A separate core from Camp&nbsp;Century <a href="https://www.earth.com/news/city-under-the-ice-secret-base-camp-found-in-greenland/" target="_blank" rel="noreferrer noopener">near the coast</a> yielded plant remains no older than&nbsp;416,000&nbsp;years, underscoring the ice sheet’s flickering presence across the Pleistocene. 



These findings draw on material that had been stored at the National Science Foundation <a href="https://icecores.org/" target="_blank" rel="noreferrer noopener">Ice Core Facility</a> in Lakewood, Colorado, for three decades.



<h2 class="wp-block-heading" id="h-fossils-divulge-a-warmer-greenland">Fossils divulge a warmer Greenland</h2>



Under the microscope, what had looked like no more than specks floating on the surface of the melted core sample was, in fact, a window into a <a href="https://www.earth.com/news/greenland-transformation-ice-melt-plant-growth-vegetation-cascading-effects/" target="_blank" rel="noreferrer noopener">tundra landscape</a>. 



“It was amazing,” Mastro exclaimed. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/04/greenland-ice-core_soil-sample_fossils_recently-melted-ice_credit-UVermont_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/04/greenland-ice-core_soil-sample_fossils_recently-melted-ice_credit-UVermont_1s.webp" alt="Willow bud scale, arctic poppy seed, fungal bodies, and rock spikemoss megaspores found in the GISP2 soil sample viewed under a microscope at the University of Vermont. Click image to enlarge. Credit: Halley Mastro/University of Vermont" class="wp-image-1977508"/></a><figcaption class="wp-element-caption">Willow bud scale, arctic poppy seed, fungal bodies, and rock spikemoss megaspores found in the GISP2 soil sample viewed under a microscope at the University of Vermont. Click image to enlarge. Click image to enlarge. Credit: Halley Mastro/University of Vermont</figcaption></figure>



Mastro and colleagues picked out spores of spike‑moss, the bud scale of a young willow, and the compound eye of an insect - life‑forms adapted to chilly air and long summer daylight.



“And then we found Arctic poppy - just one seed of it. That is a tiny flower that's really good at adapting to the cold. It lets us know that Greenland's ice melted and there was soil, because poppies don't grow on top of miles of ice,”&nbsp;Mastro continued.



<h2 class="wp-block-heading" id="h-sea-level-risks-for-global-coasts">Sea‑level risks for global coasts</h2>



<a href="https://www.earth.com/news/fossil-corals-reveal-that-sea-level-rise-occurs-in-rapid-bursts/">Sea level today</a> is rising more than an inch each decade. “And it's getting faster and faster,” said Bierman. The extra water comes from a warming ocean that expands as well as from melting glaciers worldwide.



Near‑complete melting of Greenland’s ice over the next centuries to a few millennia would lead to some&nbsp;23&nbsp;feet of sea‑level rise. 



“Look at Boston, New&nbsp;York, Miami, Mumbai, or any other coastal city around the world, and add&nbsp;20‑plus feet of sea level. It goes underwater. Don't buy a beach house," Bierman advised.



<a href="https://www.earth.com/news/how-much-did-sea-levels-rise-after-the-last-ice-age-alarming-new-clues-revealed/" target="_blank" rel="noreferrer noopener">Sea level</a> is likely to be several feet higher by the end of this century, when today’s children are grandparents.



<h2 class="wp-block-heading" id="h-greenland-s-fragile-ice-fortress">Greenland's fragile ice fortress</h2>



Richard Alley, a leading climate scientist at <a href="https://www.psu.edu/" target="_blank" rel="noreferrer noopener">Penn State University</a>, reviewed the new research.



“This new study confirms, and expands upon earlier evidence, that significant sea‑level rise occurred at a time when the causes of warming were not especially extreme, providing a warning of the damage we might cause if we continue to warm the climate," Alley noted.



“We now have direct evidence that not only was the ice gone, but that plants and insects were living there,” Bierman concluded. “And that's unassailable. You don't have to rely on calculations or models.” 



The fossil soil at Greenland’s summit, locked beneath nearly two miles of ice, speaks plainly: polar ice sheets can retreat far and fast when the climate tips, and the coastlines of the future will trace that story in real time. 



Whether that warning is heeded remains a decision for policy makers and citizens alike.



The full study was published in the journal <a href="https://www.pnas.org/doi/10.1073/pnas.2407465121#supplementary-materials" target="_blank" rel="noreferrer noopener">Proceedings of the National Academy of Sciences</a>.



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Greenland ice discovery stuns and worries scientists: "Don't buy a beach house"

Greenland’s ice-covered landscape looks like an immovable block on satellite...

Neon‑hued breakfast cereals, microwave‑ready pizzas, and oversized bags of chips now crowd supermarket aisles. A new study draws a sharp line between that convenience found in ultra-processed foods and a cluster of early warning signs for chronic disease.



“It may be about the additives, the packaging, even the marketing,” said <a href="https://mira.mcmaster.ca/our-faculty/anthea-christoforou/" target="_blank" rel="noreferrer noopener">Anthea Christoforou</a> of McMaster University, who led the investigation.



<h2 class="wp-block-heading" id="h-understanding-ultra-processed-foods">Understanding ultra-processed foods</h2>



Ultra-processed foods (UPFs) are <a href="https://www.earth.com/news/breaking-free-from-ultra-processed-foods-the-surprising-health-benefits/">industrial concoctions</a> designed for convenience, shelf life, and hyper-palatability. 



Think of packaged snacks, sugary cereals, soda, instant noodles, and frozen meals - these aren't just "processed," they're engineered. 



Manufacturers strip raw ingredients of their natural nutrients, then add fats, sugars, artificial flavors, emulsifiers, preservatives, and colorings to craft something addictive and uniform. 



The result is food that barely resembles its original form and is often high in calories but low in real nutrition.



The trouble is, UPFs are everywhere - and they're linked to a rising tide of <a href="https://www.earth.com/news/ultra-processed-foods-make-our-bodies-age-faster/">chronic health issues</a>. 



<h2 class="wp-block-heading" id="h-ultra-processed-foods-raise-alarms">Ultra‑processed foods raise alarms</h2>



Health agencies classify foods by how much industry tampering they undergo, a system formalized in the <a href="https://pubmed.ncbi.nlm.nih.gov/38418082/" target="_blank" rel="noreferrer noopener">NOVA classification</a>. 



In the Canadian sample, daily intake averaged just over three servings of these items, but the top quarter of participants swallowed nearly six, crowding out fruit and vegetables.



A landmark metabolic‑ward trial showed that volunteers offered ultra‑processed food menus ate about 500 extra calories per day compared with identical nutrient profiles made from <a href="https://www.earth.com/news/new-tool-lets-you-check-how-processed-your-food-is-grocerydb/">unprocessed foods</a>. 



Participants in that study gained nearly two pounds in just two weeks, underscoring the silent calorie creep of factory‑formulated meals.



<h2 class="wp-block-heading" id="h-inflammation-is-the-hidden-spark">Inflammation is the hidden spark</h2>



Among the strongest signals in the McMaster dataset was a rise in <a href="https://www.uscjournal.com/articles/high-sensitivity-c-reactive-protein-atherosclerotic-cardiovascular-disease-measure-or-not?language_content_entity=en" target="_blank" rel="noreferrer noopener">C‑reactive protein</a>, a liver‑made marker that flags systemic inflammation. 



High levels of this protein are now listed as a heart‑disease risk enhancer, so its appearance in heavy snackers hints at trouble brewing beneath the skin.



“These foods are causing an inflammatory response, in a sense our bodies see them as some kind of other element,” Christoforou explained.



<h2 class="wp-block-heading" id="h-beyond-the-bathroom-scale">Beyond the bathroom scale</h2>



Skeptics sometimes argue that the harms of packaged foods stem solely from the extra pounds they add, yet the study adjusted for body mass index and still saw higher insulin and triglycerides in high‑UPF eaters.



Prospective U.S. cohorts reached a similar conclusion, linking high UPF diets to a 24 percent jump in type 2 diabetes risk even after accounting for weight changes. 



<a href="https://www.niddk.nih.gov/about-niddk/staff-directory/biography/hall-kevin" target="_blank" rel="noreferrer noopener">Kevin Hall</a>’s metabolic‑ward <a href="https://pubmed.ncbi.nlm.nih.gov/31105044/" target="_blank" rel="noreferrer noopener">experiment</a> supports that idea, showing that people chewed faster, finished meals sooner, and felt less full when the dishes were ultra‑processed.



<h2 class="wp-block-heading" id="h-socioeconomic-angles-and-policy-gaps">Socioeconomic angles and policy gaps</h2>



In the McMaster survey, heavy UPF eaters were more likely to have lower incomes and less formal education. 



“The health risks persist independently of income and education, highlighting the need for broad, equitable food policies,” warned Angelina Baric, a graduate student co‑author.



An <a href="https://pubmed.ncbi.nlm.nih.gov/38719536/" target="_blank" rel="noreferrer noopener">analysis</a> covering 45 million person‑years estimated that cutting UPF intake could avert thousands of premature deaths annually.



<h2 class="wp-block-heading" id="h-marketing-that-targets-children">Marketing that targets children</h2>



Ultra-processed foods aren’t just convenient, they’re <a href="https://www.earth.com/news/ultraprocessed-foods-pose-major-health-risks-especially-for-kids/">aggressively marketed</a>. From children’s cartoons on cereal boxes to bold health claims on energy bars, these strategies are designed to shape preferences early and build loyalty. 



<a href="https://jamanetwork.com/journals/jamainternalmedicine/article-abstract/2653912" target="_blank" rel="noreferrer noopener">Research</a> shows that marketing exposure significantly influences eating habits, especially among youth and low-income populations who may have fewer healthy options available.



Many of these products carry front-of-package labels that promote added fiber, vitamins, or protein, giving a false impression of health. These claims often distract from the overall quality of the food. 



<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6364956/">Studies</a> have shown that nutrient-focused labels can mislead consumers into thinking a product is healthier than it actually is, even when it’s high in added sugar or sodium.



<h2 class="wp-block-heading" id="h-food-matrix-and-biological-effects">Food matrix and biological effects</h2>



One of the more <a href="https://www.earth.com/news/eating-ultra-processed-foods-makes-your-muscles-weaker-and-more-fragile/">overlooked aspects</a> of ultra-processed foods is how they alter the food matrix, the physical and chemical structure of what we eat, which affects how it’s digested and absorbed. 



By breaking down fiber, emulsifying fats, and adding sugars, UPFs speed up digestion, increase glycemic load, and can bypass natural satiety signals.



There’s growing concern that these structural changes may harm the gut microbiome, the community of microbes that helps regulate immunity and metabolism. 



Research suggests certain emulsifiers and artificial sweeteners commonly used in UPFs can disrupt gut bacteria and may lead to inflammatory responses, insulin resistance, and other metabolic issues.



<h2 class="wp-block-heading" id="h-future-of-ultra-processed-foods">Future of ultra‑processed foods</h2>



Dialing back UPF does not require an all‑or‑nothing pledge; replacing even one daily serving with whole fruit or unsalted nuts trimmed inflammatory markers in trials.



Dietitians recommend starting with breakfast, swapping sugared cereal for oatmeal, then moving on to snacks, habits that nudge down average servings without demanding perfection. 



<a href="https://www.canada.ca/en/health-canada/services/food-nutrition/food-safety/food-additives.html" target="_blank" rel="noreferrer noopener">Health Canada</a> is already reviewing additives and marketing rules, and the new biomarker evidence gives those deliberations fresh urgency.



The study is published in <a href="https://nutritionandmetabolism.biomedcentral.com/articles/10.1186/s12986-025-00935-y" target="_blank" rel="noreferrer noopener">Nutrition &amp; Metabolism</a>.



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Study confirms direct link between ultra-processed foods and serious health problems

Neon‑hued breakfast cereals, microwave‑ready pizzas, and oversized bags of chips...

Sharks have survived five mass extinctions and ruled the oceans for over 400 million years. As apex predators, they play a critical role in maintaining the balance of marine ecosystems.&nbsp;But today, sharks are more threatened than ever. 



On Shark Awareness Day, we highlight the science behind their importance. Without sharks, ocean ecosystems would become unbalanced, leading to overpopulation of some species and the collapse of others.



This disruption would harm the overall health of the <a href="https://www.earth.com/news/ocean-climate-fixes-could-worsen-the-oxygen-crisis/">ocean</a>, ultimately affecting food security and coastal economies.



<h2 class="wp-block-heading" id="h-what-happens-when-sharks-disappear">What happens when sharks disappear?</h2>



A <a href="https://www.earth.com/news/top-predator-missing-what-happens-when-great-white-sharks-disappear/#google_vignette">long-term study</a> conducted in False Bay, South Africa, offers a real-world example of what happens when sharks disappear from an ecosystem.



The researchers found that by mid‑2018, great white sharks had vanished from the region. This led to dramatic shifts throughout the ecosystem.&nbsp;



With the disappearance of great whites, Cape fur seal and sevengill shark populations surged, while their prey - smaller fish and bottom-dwelling shark species - declined sharply.&nbsp;



The findings provide real-world evidence of a “trophic cascade,” where the loss of a top predator triggers a ripple effect through lower levels of the food web.



The researchers suggest that the sharks may have disappeared due to several potential causes, including targeted attacks by orcas - which have been observed killing and eating great white livers.&nbsp;



The study demonstrates the importance of apex predators in maintaining ocean health. The research highlights how their loss can destabilize marine webs and reduce biodiversity.



<h2 class="wp-block-heading" id="h-declining-shark-populations-nbsp">Declining shark populations&nbsp;</h2>



According to a <a href="https://www.earth.com/news/overfishing-has-caused-a-50-decline-in-sharks-and-rays/">study</a> led by researchers from Simon Fraser University, over half of all sharks and rays have disappeared globally since 1970 - with overfishing identified as the primary cause.&nbsp;



Sharks and rays, serving as critical predators and sediment stirrers, help maintain food webs and nutrient flows. The report revealed that around one-third of shark and ray species now face extinction. 



However, there is cause for hope: countries such as Australia, Canada, New Zealand, the US, parts of Europe, and South Africa have implemented science-based fishing limits, reduced bycatch, and protected critical habitats.



<h2 class="wp-block-heading" id="h-endangered-shark-species-nbsp">Endangered shark species&nbsp;</h2>



Among the most threatened are the great <a href="https://www.earth.com/news/why-some-great-hammerhead-sharks-rarely-leave-home/">hammerhead</a> and the scalloped hammerhead sharks - both of which have seen dramatic population declines worldwide.&nbsp;



These species are particularly vulnerable because they grow slowly and reproduce rarely, making it hard for their populations to bounce back once they decline.



The oceanic whitetip shark, once abundant across tropical and subtropical waters, has suffered steep losses from bycatch and targeted fishing - pushing it toward critical endangerment.&nbsp;



Many deep-sea sharks, like the bluntnose sixgill and the gulper shark, are also threatened due to slow reproduction rates combined with increased fishing pressures.



<h2 class="wp-block-heading" id="h-campaigns-around-the-world">Campaigns around the world</h2>



Around the world, numerous campaigns and organizations are dedicated to protecting sharks and raising awareness about their critical role in ocean ecosystems.&nbsp;



One of the most widely recognized efforts is <a href="https://www.discovery.com/shark-week/shark-week-2025-kicks-off-july-20">Shark Week</a>, a series on the Discovery Channel that draws millions of viewers each summer. Through documentaries and expert interviews, the series highlights both the awe-inspiring nature of sharks and the threats they face from human activity.



<a href="https://iucn.org/our-union/members/iucn-members/project-aware-foundation">Project AWARE</a> mobilizes scuba divers globally to advocate for shark conservation by pushing for bans on shark finning and the creation of marine protected areas.&nbsp;



On a larger scale, coalitions like the <a href="https://www.globalsharkmovement.org/">Global Shark Movement Project</a> work to influence policy and fisheries management worldwide.



The International Union for Conservation of Nature (IUCN) <a href="https://www.iucnssg.org/">Shark Specialist Group</a> also plays a vital role by assessing species status and guiding conservation strategies globally.&nbsp;



Together, these campaigns combine public education, advocacy, and policy efforts to reduce shark deaths and support healthier oceans for future generations.



<h2 class="wp-block-heading" id="h-celebrate-shark-awareness-day-nbsp">Celebrate Shark Awareness Day&nbsp;</h2>



Shark Awareness Day highlights the urgent need for stronger protections and <a href="https://www.earth.com/news/sustainable-fishing-must-be-redefined-to-halt-ocean-destruction/">sustainable fishing practices</a> to prevent the irreversible loss of these vital ocean predators.



Today, people around the world are encouraged to learn about sharks and the threats they face from human activities. We are also encouraged to take action by choosing sustainable seafood and speaking up for better laws to protect sharks.&nbsp;



Shark Awareness Day helps build a stronger global community committed to conservation efforts. Ultimately, protecting sharks is about protecting the entire ocean system - and a planet that depends on it.



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Shark Awareness Day: Protecting the balance of the ocean 

Sharks have survived five mass extinctions and ruled the oceans...

What started as a student field trip along the cliffs of Dorset turned into the discovery of a new prehistoric species. A 16.5-millimeter lower jaw, embedded in rock near Swanage, is now reshaping how scientists view early mammal evolution.



The discovery was made by an undergraduate student from the <a href="https://www.port.ac.uk/">University of Portsmouth</a>. The fossil belongs to a type of extinct mammal called a multituberculate. 



These small, rodent-like creatures once lived alongside <a href="https://www.earth.com/news/where-did-dinosaurs-come-from-missing-fossils-hold-the-secret/">dinosaurs</a> and were known for their distinctively complex teeth.



<h2 class="wp-block-heading" id="h-a-curious-jaw-a-surprising-species">A curious jaw, a surprising species</h2>



The fossil was uncovered at Durlston Bay, a site famous for its rich geological layers. It’s the first multituberculate jaw found there since the 1800s. 



Though it looks a bit like a rabbit's jaw at first glance, the structure of the teeth tells a different story. A sharp incisor juts out at the front, followed by a gap, and then four blade-like premolars.



“I instantly had my suspicions of what the jaw was when I found it at the beach, but couldn’t have imagined where the discovery would take me,” said Ben Weston,&nbsp;an undergraduate paleontology student.



“I’m extremely grateful to the team and to the university for helping me take my first steps into academic paleontology.”



Researchers at the University of Portsmouth confirmed that the fossil is from a species that had never been identified before.



<h2 class="wp-block-heading" id="h-technology-brings-the-fossil-to-life">Technology brings the fossil to life</h2>



The fossil wasn’t easy to examine. Rock still clung to key parts of the specimen. To get around this, the team turned to high-resolution <a href="https://www.earth.com/news/gordonia-traquairi-pig-like-creature-discovered-roamed-earth-250-million-years-ago/">CT scanning</a>. 



Dr. Charles Wood, a senior scientific officer at the university, scanned the fossil, allowing scientists to see inside the rock without damaging the sample.



Jake Keane, a former Portsmouth paleontology student now working in Abu Dhabi, helped process the scans. In just a few hours, he digitally removed the surrounding rock and isolated the teeth in fine detail.



The scans were then turned into 3D-printed models by John Fearnly, lead technician in the university’s Faculty of Technology. These models were ten times larger than the original, making it safer and easier to study the fossil in depth.



<h2 class="wp-block-heading" id="h-new-mammal-gets-a-name">New mammal gets a name</h2>



The team named the new species Novaculadon mirabilis. “Novacula” means razor, a nod to its sharp back teeth. “Mirabilis” refers to the jaw’s almost perfect preservation.



Portsmouth student Hamzah Imran created an artistic rendering of the animal. It’s imagined as a small, furry creature with a mix of spots and stripes - though its actual appearance remains speculative.



Based on its teeth, Novaculadon mirabilis likely ate <a href="https://www.earth.com/news/very-little-is-known-about-99-of-all-insects-on-earth/">insects</a> and other small <a href="https://www.earth.com/news/ocean-noise-can-be-fatal-to-marine-invertebrates/">invertebrates</a>. Its slicing premolars and pointed incisors set it apart from modern rodents like rats or squirrels.



<h2 class="wp-block-heading" id="h-a-hotspot-for-new-mammal-species">A hotspot for new mammal species</h2>



This isn't the first time a student has made a big find in the same area. In 2017, another Portsmouth undergraduate, Grant Smith, discovered fossils of two new <a href="https://www.earth.com/news/where-mammals-live-depends-more-on-climate-than-human-activities/">mammal</a> species thought to be among humanity’s earliest relatives.



Dr. Steve Sweetman, a researcher at the University of Portsmouth, also worked on this new discovery. 



“This is a remarkable find that reminds me of when Grant found those extraordinary eutherian mammal teeth," said Dr. Sweetman.



"When I first saw Grant's specimens, my jaw dropped - and I had exactly the same reaction to Ben's multituberculate jaw. It's incredible that Durlston Bay keeps delivering such significant mammal discoveries by our undergraduate students.”



<h2 class="wp-block-heading" id="h-evolution-insights-from-tiny-jaw">Evolution insights from tiny jaw </h2>



Beyond the scientific importance, the discovery highlights the value of collaborative research. 



“Looking back now that the discovery has been published, I am amazed at how many people it took to describe this little mammal," said Professor David Martill.



"I especially appreciated that all team members were University staff or present and former students - a true team effort including academics, technicians, alumni, and students with diverse talents across three departments.” 



The fossil helps researchers better understand how early mammals survived during the age of dinosaurs. While multituberculates lived through the <a href="https://www.earth.com/news/what-was-the-cause-of-earths-largest-mass-extinction/">mass extinction</a> that wiped out dinosaurs, they eventually died out during the Oligocene, around 33 million years ago.



With over 200 known species, multituberculates were the most diverse group of mammals in the Mesozoic era. They filled many ecological roles - some burrowed, others climbed trees. This new discovery adds to what we know about their evolution and survival.



And it serves as a reminder that major scientific contributions can come from anyone - even a 22-year-old student on a windy beach in Dorset.



Image Credit: Hamzah Imran



The full study was published in the journal <a href="https://dx.doi.org/10.1016/j.pgeola.2025.101128">Proceedings of the Geologists Association</a>.



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Tiny fossil, big discovery: Student uncovers a lost mammal species

What started as a student field trip along the cliffs...

Senior,Couple,,Smiling,,Mature,Man,And,Woman,Doing,Plank,Exercise

Exercise is medicine. Most of us have heard that advice more times than we can count. But what if the best way to treat high blood pressure doesn’t involve running miles or lifting heavy weights? What if the most effective exercise is one where you barely move at all?



A major new analysis published in the&nbsp;British Journal of Sports Medicine challenges decades of assumptions about how we should approach blood pressure control. The study dives deep into nearly three decades of clinical research.



Its surprising conclusion? Static strength <a href="https://www.earth.com/news/how-to-maximize-the-mental-health-benefits-of-exercise/">exercises</a> like wall sits and planks may be more effective at reducing blood pressure than popular choices like cardio or high intensity interval training.



The research team behind the study set out to uncover the most effective forms of exercise to prevent and manage arterial hypertension. 



The findings not only expand our understanding of how exercise influences blood pressure, but also call for a major update to current medical guidelines.



<h2 class="wp-block-heading" id="h-exercise-types-and-blood-pressure">Exercise types and blood pressure</h2>



The researchers systematically reviewed 270 randomized controlled trials conducted between 1990 and February 2023. These trials involved a total of 15,827 participants and explored how various forms of exercise affect resting blood pressure.



To compare outcomes fairly, the researchers categorized <a href="https://www.earth.com/news/exercise-feels-better-when-its-matched-to-your-personality/">exercise</a> routines into five main groups: aerobic training, dynamic resistance training, combined training, high intensity interval training (HIIT), and isometric exercise training.



Aerobic training included activities such as walking, running, and cycling. Dynamic resistance training referred to exercises that involve movement and weight, like squats or push-ups. Combined training used both aerobic and resistance approaches. 



HIIT referred to short bursts of intense exercise alternated with low intensity recovery. Finally, isometric training focused on muscle engagement without visible movement, such as wall sits or planks.



The researchers assessed both systolic blood pressure (SBP), the pressure during heartbeats, and diastolic blood pressure (DBP), the pressure between beats. 



Using advanced statistical tools like Bayesian network meta-analysis, they compared all five exercise categories head to head.



<h2 class="wp-block-heading" id="h-exercises-for-lower-blood-pressure">Exercises for lower blood pressure</h2>



All five types of <a href="https://www.earth.com/news/exercise-reduces-depression-and-anxiety-in-children-and-teens-with-mental-health-issues/">exercise</a> reduced blood pressure significantly. But not all changes were equal. Isometric training emerged as the clear leader. 



This type of exercise led to an average systolic reduction of 8.24 mmHg and a diastolic drop of 4.00 mmHg.



In comparison, combined training lowered systolic pressure by 6.04 mmHg. Dynamic resistance came next with 4.55 mmHg, followed by aerobic training at 4.49 mmHg and HIIT at 4.08 mmHg.



Diastolic pressure showed a similar trend. Isometric training again topped the list with a 4 mmHg reduction, followed by resistance training at 3.04 mmHg, combined training at 2.54 mmHg, aerobic training at 2.53 mmHg, and HIIT at 2.50 mmHg.



“Overall, isometric exercise training is the most effective mode in reducing both systolic and diastolic blood pressure,” noted the researchers.



This finding may seem surprising at first. After all, isometric exercises don’t involve much movement. But their intensity and sustained muscle contraction appear to create powerful cardiovascular benefits.



<h2 class="wp-block-heading" id="h-best-routines-for-blood-pressure">Best routines for blood pressure </h2>



The study didn’t just stop at general categories. It also looked at specific forms of exercise within each group that helped with blood pressure management. 



Among all the routines analyzed, wall squats produced the most powerful drop in systolic pressure, averaging 10.47 mmHg. 



When it came to diastolic pressure, running delivered the biggest benefit, with an average reduction of 5.67 mmHg.



Other standout performers included cycling, which had stronger effects than walking in both pressure types. Walking, though widely recommended, showed the smallest benefit in this comparison.



<h2 class="wp-block-heading" id="h-benefits-for-people-with-hypertension">Benefits for people with hypertension</h2>



Interestingly, aerobic training showed greater blood pressure reductions when performed less frequently. 



The data suggested that training three times per week produced better results than training five times per week or more. This finding applied only to aerobic training and not to the other exercise modes.



The experts found that people with hypertension experienced the largest improvements. For them, isometric training lowered systolic pressure by as much as 12.2 mmHg. 



In contrast, the average drop was about 6.65 mmHg in people with normal blood pressure. This suggests that the benefits are even more pronounced in those who need them most.



<h2 class="wp-block-heading" id="h-where-does-hiit-fit-in">Where does HIIT fit in?</h2>



High intensity interval <a href="https://www.earth.com/news/to-get-fit-and-stay-healthy-walk-this-exact-distance-every-day/">training</a> has gained popularity in recent years due to its time efficiency and metabolic benefits. However, in this review, HIIT ranked lowest among all exercise types for lowering systolic pressure. 



When broken down further, sprint interval training (SIT) showed some benefit, while aerobic interval training (AIT) failed to reach statistical significance for either systolic or diastolic blood pressure.



The authors emphasized that intensity does play a role. While walking had modest effects, running and cycling offered stronger outcomes. This highlights the importance of exercise quality over quantity.



Even though HIIT didn’t lead the rankings, the authors acknowledged its growing appeal. It remains a practical choice for people short on time. 



But for those seeking the strongest impact on blood pressure, isometric holds may offer more powerful results in a shorter span.



<h2 class="wp-block-heading" id="h-the-need-to-update-exercise-guidelines">The need to update exercise guidelines</h2>



Current exercise guidelines for blood pressure control focus primarily on aerobic activities. But those guidelines are based on older data. This review brings in newer research, including many more trials on isometric and HIIT workouts.



“These findings provide a comprehensive data driven framework to support the development of new exercise guideline recommendations for the prevention and treatment of arterial hypertension,” the authors wrote.



They also noted that blood pressure reductions from isometric training are comparable to those seen with standard dose antihypertensive medications. 



That makes isometric exercise a powerful tool for people who either can’t tolerate medication or want to try non drug approaches first.



While some doctors may still be unfamiliar with using static holds as a prescription, the science is catching up quickly. 



The field now has much more confidence in the effectiveness of these routines, thanks to a growing number of well conducted trials.



<h2 class="wp-block-heading" id="h-simple-exercises-lower-blood-pressure">Simple exercises lower blood pressure </h2>



It turns out that the simplest exercises, those that require no equipment, no running, and very little space, may do the most for your blood pressure. 



Wall sits, planks, and other isometric exercises demand effort without motion, yet offer results that rival, and in some cases exceed, more traditional workouts.



If you're managing high blood pressure or trying to avoid it, consider adding static holds to your weekly routine. The evidence is now stronger than ever. 



Just a few short sessions per week could make a measurable difference and might even take the pressure off your heart.



The authors are from&nbsp;<a href="https://www.canterbury.ac.uk/" target="_blank" rel="noreferrer noopener">Canterbury Christ Church University</a>&nbsp;and the&nbsp;<a href="https://le.ac.uk/" target="_blank" rel="noreferrer noopener">University of Leicester</a>&nbsp;in the UK. 



The study is published in the <a href="https://bjsm.bmj.com/content/57/20/1317" target="_blank" rel="noreferrer noopener">British Journal of Sports Medicine</a>. 



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These types of exercises are better than running or walking for controlling blood pressure

Exercise is medicine. Most of us have heard that advice...

Niagara Falls pulls in tourists by the boatload. Angel Falls towers higher than city skyscrapers. Yet both pale in comparison to Earth's largest waterfall - an enormous, rushing torrent concealed below Arctic waves.



The Denmark Strait cataract drops in slow motion beneath the chilly surface between Iceland and Greenland. 



The chute begins thousands of feet down, rolls over a hidden ledge, and keeps sliding for 11,500 feet.



No roar reaches the surface, no mist fills the air, and passing ships glide on as if nothing remarkable lies below these crucial <a href="https://www.earth.com/news/atlantic-and-arctic-mixing-is-crucial-for-earths-climate-stability/">Arctic waters</a>, which drive Earth's climate.



<h2 class="wp-block-heading" id="h-the-denmark-strait-cataract">The Denmark Strait cataract</h2>



Most of Earth's largest waterfalls form when a river meets a cliff and spills over. Turbulent water gouges the rock, the lip grows steeper, and a postcard scene is born. 



<a href="https://www.nature.com/articles/s41598-024-75984-z" target="_blank" rel="noreferrer noopener">Submarine waterfalls</a> follow a different script. Here, colder, saltier water sinks below lighter layers, slipping along the seafloor like syrup down a tilted pan. The motion is silent, pulling entire water masses rather than a single stream.



Oceanographers first confirmed the Denmark Strait cataract decades ago by tracing temperature and salinity profiles through the channel. 



Sensors revealed a dense ribbon of <a href="https://www.earth.com/news/arctic-ocean-stayed-partly-open-during-harsh-ice-ages/">Nordic Sea</a> water sliding into the Atlantic basin, gathering speed until it tumbled past a submerged ridge. That ridge acts as the unseen cliff, setting off the tallest plunge on Earth.



<h2 class="wp-block-heading" id="h-where-arctic-chill-meets-atlantic-warmth">Where Arctic chill meets Atlantic warmth</h2>



Icy water leaving the Nordic seas is both colder and saltier than the milder Atlantic layer to the south. Density differences created by that contrast drive the flow. 



As the dense water reaches the sill between <a href="https://www.earth.com/image/rare-glimpse-of-iceland-amid-unusual-heatwave/">Iceland</a> and <a href="https://www.earth.com/news/greenland-ice-fossil-tundra-discovery-stuns-and-worries-scientists-sea-level-rise/">Greenland</a>, it spills downward, widening as it falls until the sheet stretches roughly 300 miles - about the driving distance from Chicago to St. Louis.



During the <a href="https://www.earth.com/news/lessons-from-the-ice-age-how-climate-change-reshapes-plant-life/">Last Ice Age</a>, roughly 17,500 to 11,500 years ago, glaciers carved trenches across the seabed and left behind the ridge that now serves as the cataract’s tipping point. 



Glacial debris, <a href="https://www.earth.com/news/rocks-explain-roman-empire-collapse-1500-years-ago-late-antique-little-ice-age/">volcanic eruptions</a>, and relentless currents have since hardened the structure, locking a geological funnel in place for the descending water.



<h2 class="wp-block-heading" id="h-climate-change-and-the-largest-waterfall">Climate change and the largest waterfall</h2>



More than 3.2 million cubic meters of water - around 113 million cubic feet - slip over the cataract every second, far outpacing the Amazon River’s flow into the Atlantic. 



This slide feeds the lower limb of the Atlantic Meridional Overturning Circulation (<a href="https://www.nature.com/articles/s43247-025-02403-0" target="_blank" rel="noreferrer noopener">AMOC</a>), the global “conveyor belt” that ferries heat, oxygen, and nutrients around the planet.



There is increasing evidence of the effects of global change on the phenomenon of undersea waterfalls. 



“A good example is on the <a href="https://www.earth.com/image/the-ebro-river-on-the-northeast-coast-of-spain/">Catalan coast</a>, where the decrease in the number of tramontane days in winter in the Gulf of Lion and north of the Catalan coast is causing a weakening of this oceanographic process, which is decisive in regulating the climate and has a great impact on deep ecosystems,” explains marine scientist <a href="https://www.researchgate.net/profile/Anna-Sanchez-Vidal" target="_blank" rel="noreferrer noopener">Anna Sanchez Vidal</a>.



<h2 class="wp-block-heading" id="h-size-of-the-denmark-strait-cataract">Size of the Denmark Strait cataract</h2>



<a href="https://en.wikipedia.org/wiki/Angel_Falls" target="_blank" rel="noreferrer noopener">Angel Falls</a> drops 3,212 feet in Venezuela. Niagara clears a modest 167 feet on the U.S.-Canada border. Stack all of Niagara’s water several dozen times, and you still won’t match the cataract’s flow. 



Even the Mississippi at flood stage would struggle. Yet the Denmark Strait cataract remains invisible, its roar muffled by more than a half-mile of seawater.



Instruments tell a different story: moored profilers register velocities topping three knots, while sediment cores show layers rearranged by the hidden torrent.



The phenomenon of dense water overflow is particularly intense in the Arctic and Antarctic. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/denmark-strait-cataract_graphic-illustration_credit-NOAA_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2024/12/denmark-strait-cataract_graphic-illustration_credit-NOAA_1s.webp" alt="In the Denmark Strait, southward-flowing frigid water from the Nordic Seas meets warmer water from the Irminger Sea. The cold, dense water quickly sinks below the warmer water and flows over the huge drop in the ocean floor, creating a downward flow estimated over 123 million cubic feet per second. Credit: NOAA" class="wp-image-1977524"/></a><figcaption class="wp-element-caption">In the Denmark Strait, southward-flowing frigid water from the Nordic Seas meets warmer water from the Irminger Sea. The cold, dense water quickly sinks below the warmer water and flows over the huge drop in the ocean floor, creating a downward flow estimated over 123 million cubic feet per second. Click image to enlarge. Credit: NOAA</figcaption></figure>



“The poles are the regions where most of the dense water masses - generated by the formation of sea ice at the surface - eventually reach the global ocean floor," explains David Amblàs of the <a href="https://www.ub.edu/portal/web/earth-sciences/faculty" target="_blank" rel="noreferrer noopener">Department of Earth and Ocean Dynamics</a> at the University of Barcelona. 



"The polar areas are like the heart of the oceanic circulatory system: they pump cold, dense water into the great oceanic troughs through the ‘heartbeats’ made by overflows of dense water."



<h2 class="wp-block-heading" id="h-much-more-to-learn">Much more to learn</h2>



The cataract may slow or speed up as <a href="https://www.earth.com/news/drastic-warming-will-transform-the-arctic-beyond-recognition/">Arctic warming</a> alters salinity and temperature patterns. Researchers use autonomous gliders, deep-sea landers, and satellite altimetry to watch for any shift that could ripple through weather systems. 



A weakening flow might stall the North Atlantic’s heat pump, cooling Europe and nudging hurricanes onto new tracks.



Yet there is still no direct video of the full descent, and no sensor array captures every eddy. Each expedition peels back only a sliver of the story. 



Future projects aim to stitch those slivers together, mapping the plunge in three dimensions and tracking its pulse through the seasons.



<h2 class="wp-block-heading" id="h-why-earth-s-largest-waterfall-matters">Why Earth's largest waterfall matters</h2>



Anyone enjoying mild January weather or a fish fillet pulled from Icelandic waters owes thanks, in part, to the Denmark Strait cataract. 



By dragging cold, dense water southward, the cataract clears space for warmer <a href="https://www.earth.com/news/weakening-ocean-currents-could-cost-trillions-of-dollars/">Gulf Stream water</a> to flow north. That exchange tempers winter, nourishes plankton, and steers migratory species toward fertile feeding grounds.



When the torrent quickens, more carbon-rich deep water rises elsewhere, boosting ocean productivity. When it slackens, heat piles up in the tropics, whipping up stronger storms. 



In other words, the waterfall no one can see holds a backstage pass to everyday weather and the seafood aisle alike.



From a tourist’s point of view, the cataract offers nothing to watch. From a planetary perspective, it's a crucial lever, tilting climate and commerce with the quiet push of density-driven flow. 



Scientists will keep chasing its rhythm, because the better we know this hidden giant, the better we can forecast the moods of the sea and the sky above it.



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Earth’s largest waterfall, dwarfing all others, is hidden in the ocean

Niagara Falls pulls in tourists by the boatload. Angel Falls...

Diseño sin título - 1

A beautiful turquoise‑and‑lilac sea creature that has been kept in hobbyist aquariums around the world for nearly two decades has finally been given a scientific species name. 



The modest crustacean hiding in plain sight turns out to be Cherax pulverulentus, an entirely new crayfish species no biologist had cataloged until now.



<a href="https://www.researchgate.net/profile/Jiri-Patoka" target="_blank" rel="noreferrer noopener">Jiří Patoka</a> of the <a href="https://www.czechuniversities.com/catalogue-of-universities/czech-university-of-life-sciences-prague" target="_blank" rel="noreferrer noopener">Czech University of Life Sciences Prague</a> and an international team realized the oversight while inspecting a shipment of Indonesian pets in 2023. 



Their detective work now ends years of speculation about the animal’s identity in the scientific community worldwide.



<h2 class="wp-block-heading" id="h-meet-cherax-pulverulentus">Meet Cherax pulverulentus</h2>



Ever since the early 2000s, importers have marketed the animal under nicknames such as “Blue Moon” and “Hoa Creek,” labels that lumped several look‑alike <a href="https://www.earth.com/news/earth-may-have-three-million-undiscovered-animal-species/">species</a> together. 



Dealers moved thousands of specimens across Europe, the United States, Japan, and Indonesia, yet museum drawers remained empty of an official voucher specimen.



Collectors recognized the flashy colors, but the mix of hues muddied any attempt to match the pet to known taxa. Without an authoritative description, conservation agencies could not track exports or assess wild harvest pressure.



Field notes hinted that the mystery crayfish came from forested headwaters near Ayamaru Lake in the Bird’s Head Peninsula of western New Guinea. 



Border checkpoints rarely scrutinized small ornamental shipments, allowing animals to flow from creeks to storefronts without paperwork.



<h2 class="wp-block-heading" id="h-cherax-pulverulentus-has-two-forms">Cherax pulverulentus has two forms</h2>



The research team reports that purple‑form individuals sport turquoise bodies dusted with violet specks. Their joints and tail fans fade to a chalky white, producing an almost pastel appearance that appeals to aquarists.



Blue‑form animals replace those lilac freckles with a deep navy background that drifts toward black around the claws. 



Bright orange stripes frame the abdomen and legs, giving the crayfish a stark, two‑tone look unique within the genus.



Patoka and colleagues chose the species epithet pulverulentus, Latin for “covered with dust,” to capture these pinpoint spots. 



The name, Cherax pulverulentus, cements the animal’s singular identity and separates it from <a href="https://academic.oup.com/jcb/article-abstract/35/6/830/2547908" target="_blank" rel="noreferrer noopener">Cherax pulcher</a>, a close relative described in 2015.



<h2 class="wp-block-heading" id="h-detective-work-in-the-lab">Detective work in the lab</h2>



Traditional morphometrics ranked claw shape, eye size, and rostrum length against 38 allied species. DNA barcoding of the mitochondrial COI gene then revealed at least 2 percent divergence from every known member of the genus.



“This <a href="https://www.earth.com/news/saving-biodiversity-scientists-discover-hidden-pattern-guiding-species-distributions/">species</a> has been exploited in the ornamental aquarium trade at least for 21 years,” wrote Patoka in the report. That long tenure outside science underscores how commercial networks can outpace taxonomy.



A second line of <a href="https://www.researchgate.net/publication/387844505_Cherax_pulverulentus_a_new_freshwater_crayfish_Decapoda_Parastacidae_from_Southwest_Papua_Province_Indonesia" target="_blank" rel="noreferrer noopener">evidence</a> came from nuclear 28S sequences that grouped Cherax pulverulentus as a sister lineage to C. pulcher, yet still distinct enough to rule out color morph status. 



The dual approach gives regulators a clear diagnostic toolkit should confiscated shipments require forensic identification.



<h2 class="wp-block-heading" id="h-new-guinea-streams-to-aquariums">New Guinea streams to aquariums</h2>



In the wild, the dusty crayfish digs shallow burrows into sandy streambeds shaded by rainforest canopy. Water temperatures hover near 75°F, oxygen levels stay high, and leaf litter offers both shelter and food.



The <a href="https://wwf.panda.org/discover/knowledge_hub/where_we_work/new_guinea_forests/conservation_new_guinea_forests/sites_new_guinea_forests/papua_new_guinea_bird_head_peninsula/">Bird’s Head Peninsula</a> ranks as a biodiversity hotspot, yet many of its tributaries remain unsampled by crustacean specialists. 



Local fishers collect juveniles during the dry season when water levels drop, a practice that feeds the export pipeline but leaves population trends unknown.



Little is published on the crayfish’s diet, growth rate, or breeding season. Patoka’s team calls for ecological studies that could inform sustainable quotas before demand removes more animals than nature can replace.



<h2 class="wp-block-heading" id="h-dumping-cherax-pulverulentus">Dumping Cherax pulverulentus</h2>



During the survey, one dusty crayfish turned up in a thermal spring near Budapest, Hungary, evidence that at least one aquarist released an unwanted pet. 



Similar introductions have seeded invasive populations of marbled crayfish and signal crayfish across Europe.



Non‑native crustaceans often carry the oomycete Aphanomyces astaci, the agent of crayfish plague, a disease lethal to indigenous European stocks. Even a handful of carriers can trigger a cascade that empties streams of native fauna.



Thermal refuges give tropical <a href="https://www.earth.com/news/more-than-3500-animal-species-are-directly-threatened-by-climate-change/">species</a> a foothold in colder climates. Once established, escapees outcompete local detritivores, alter nutrient cycling, and nibble on amphibian eggs, multiplying their ecological footprint.



<h2 class="wp-block-heading" id="h-why-formal-naming-matters">Why formal naming matters</h2>



Legal frameworks that govern wildlife trade, such as <a href="https://cites.org/eng/disc/what.php">CITES</a>, depend on precise species lists. 



An unnamed organism cannot be added to an appendix, leaving customs officials powerless to intercept over‑harvested cargo.



Taxonomic clarity also guides aquaculture biosecurity. Without diagnostic characters, hatchery operators may unknowingly mix species, breeding hybrids that compromise genetic integrity in the source range.



<h2 class="wp-block-heading" id="h-what-s-next-for-cherax-pulverulentus">What's next for Cherax pulverulentus?</h2>



Patoka’s group urges Indonesian authorities to map the crayfish’s distribution and to monitor harvest volumes. 



Citizen scientists photographing stream fauna with location tags could accelerate the search for hidden colonies.



Aquarists can help by buying captive‑bred stock, quarantining new arrivals, and never releasing pets into local waterways. 



Responsible hobby practice will allow enthusiasts to enjoy the dusty crayfish’s colors without endangering ecosystems.



The study is published in <a href="https://mapress.com/zt/article/view/zootaxa.5566.3.4" target="_blank" rel="noreferrer noopener">Zootaxa</a>.



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Colorful aquarium creature turns out to be a new species never catalogued by scientists

A beautiful turquoise‑and‑lilac sea creature that has been kept in...

Four tiny predators were hiding in South Korea’s limestone and lava caves, waiting for the right flashlight beam to catch their gleaming, pincer‑like jaws. These pale, eyeless pseudoscorpions - nicknamed “dragon pseudoscorpions” for their fierce-looking claws - had remained invisible to science until recently.



<a href="https://scholar.google.com/citations?user=do5tcEAAAAAJ&amp;hl=en">Ki-Hoon Jeong</a> of the <a href="https://www.nibr.go.kr/">National Institute of Biological Resources</a> and his colleagues, who made the discovery, say the creatures spend their entire lives in complete darkness - which explains their ghostly lack of color and total blindness.



<h2 class="wp-block-heading" id="h-caves-hide-rare-life">Caves hide rare life</h2>



Researchers have identified more than 1,000 caves across South Korea, yet many remain biologically uncharted. Caves form inside <a href="https://www.nps.gov/subjects/caves/karst-landscapes.htm">karst landscapes</a>, where acidic water dissolves limestone, creating isolated pockets that act like evolutionary islands for small creatures.



The perpetual night drives what biologists call <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC3639761/">troglomorphic change</a>, most often the loss of eyes and pigment together with elongated limbs and sensory hairs. 



Because each cave system isolates itself from its neighbors, animals that stumble inside can quickly diverge, creating swarms of localized species that go unnoticed by science - unless someone rappels in



<h2 class="wp-block-heading" id="h-dragon-jaws-and-vacant-eyes">Dragon jaws and vacant eyes</h2>



Jeong’s team named them Spelaeochthonius dugigulensis, S. geumgulensis, S. magwihalmigulensis, and S. yamigulensis. The adults are only about 0.08 inches long, but their chelicerae spread wide like grappling hooks.



“All species are strongly cave‑adapted and known from a single cave or karst system only,” wrote the authors. 



The pseudoscorpions wield venom‑tipped pedipalps that snap shut on springtails and <a href="https://www.earth.com/news/how-mites-survived-without-sex-for-millions-of-years/">mites</a>, yet they lack the sting and tail that give true scorpions their reputation.



Worldwide, the order <a href="https://www.mdpi.com/2075-4450/13/1/25">Pseudoscorpiones</a> already boasts more than 3,300 described species, with dozens added every year.



<h2 class="wp-block-heading" id="h-genes-confirm-the-newcomers">Genes confirm the newcomers</h2>



Field collections supplied just a handful of specimens, sometimes only one, but that was enough for DNA work. The researchers sequenced the <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC1691236/">mitochondrial COI barcode</a>, a 650‑base snippet widely used for species delimitation.



In arthropods, a 10 percent COI gap usually separates good species boundaries. The four Korean lineages showed between 13.7 and 19.8 percent divergence, easily clearing that bar. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/07/pseudoscorpions_Spelaeochthonius-dugigulensis_new-species_images_credit-Jeong_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/07/pseudoscorpions_Spelaeochthonius-dugigulensis_new-species_images_credit-Jeong_1s.webp" alt="Habitus of Spelaeochthonius dugigulensis sp. nov. A. Holotype male, dorsal view; B. Holotype male, ventral view; C. Paratype female, dorsal view; D. Paratype female, ventral view. Scale bar: 1 mm. Credit: Jeong et al." class="wp-image-1977845"/></a><figcaption class="wp-element-caption">Habitus of Spelaeochthonius dugigulensis sp. nov. A. Holotype male, dorsal view; B. Holotype male, ventral view; C. Paratype female, dorsal view; D. Paratype female, ventral view. Scale bar: 1 mm. Click image to enlarge. Credit: Jeong et al.</figcaption></figure>



Even the closest pair differed by 6.8 percent, still above the in‑house variation of less than 0.6 percent reported for single populations.



These genetic splits mirror geography: each species occupies one cave, separated from its nearest relative by scores of rocky ridges and dry valleys, natural walls that arthropods the size of sesame seeds rarely cross.



<h2 class="wp-block-heading" id="h-endemic-treasures-under-threat">Endemic treasures under threat</h2>



Blind cave life is fragile. Many Korean caves double as tourist attractions or concrete‑lined storage depots, and runoff can introduce pesticides, sewage, or construction dust.



Karst breakdown already erased one beetle, Coreoblemus parvicollis, which vanished after its only cave flooded behind the Chungju Dam, a cautionary tale cited by local conservationists.



Because the dragon pseudoscorpions live nowhere else, a single blocked entrance or polluted drip could wipe out each entire species. 



Jeong’s group urges formal protection for cave ecosystems before “dark extinction” claims more unseen lineages.



<h2 class="wp-block-heading" id="h-taxonomy-protects-cave-life">Taxonomy protects cave life</h2>



Accurate species identification is more than just naming. It sets the groundwork for conservation laws, biodiversity metrics, and habitat protection. 



Without formal recognition, these pseudoscorpions wouldn’t qualify for endangered listings or land protections, leaving them invisible in policy.



Jeong’s team used both physical features and genetic data to verify each new species. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/07/pseudoscorpions_Spelaeochthonius_new-species_genetic-analysis_credit-Jeong_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/07/pseudoscorpions_Spelaeochthonius_new-species_genetic-analysis_credit-Jeong_1s.webp" alt="Phylogenetic analyses of Spelaeochthonius shed light on species diversity and the biogeographical complexity of this genus. Credit: Jeong et al." class="wp-image-1977847"/></a><figcaption class="wp-element-caption">Phylogenetic analyses of Spelaeochthonius shed light on species diversity and the biogeographical complexity of this genus. Click image to enlarge. Credit: Jeong et al.</figcaption></figure>



Their work followed standards set by the <a href="https://www.iczn.org/">International Code of Zoological Nomenclature</a> and included digital archiving in <a href="https://zoobank.org/">ZooBank</a> to make the names valid and permanent.



<h2 class="wp-block-heading" id="h-one-cave-equals-one-species">One cave equals one species</h2>



Each cave system in this study hosted a different pseudoscorpion, and none were found anywhere else. That makes them single‑karst endemics, meaning their entire population lives in one small, isolated location. If a single cave collapses or gets sealed, that species could disappear permanently.



This kind of hyper‑local distribution is common in cave life, especially among small <a href="https://www.earth.com/news/cambrian-fossils-reveal-new-clues-about-arthropod-evolution/">arthropods</a> with limited mobility. It also means conservation decisions can’t rely on broad habitat ranges. 



Protecting these pseudoscorpions requires protecting individual caves, each one may be home to a species found nowhere else on Earth.



<h2 class="wp-block-heading" id="h-next-finds-lie-underground">Next finds lie underground</h2>



Every cave the team explored held at least one unknown pseudoscorpion, hinting that South Korea’s tally could climb from the current seven cave‑adapted species to dozens once systematic surveys begin.



With next‑generation sequencing now portable and cheap, even a few legs from a hand‑collected specimen can yield full mitochondrial genomes, opening the door to deeper evolutionary studies and faster threat assessments.



The discovery also reminds <a href="https://www.earth.com/news/humans-can-accurately-perceive-biodiversity-through-the-senses/">biodiversity</a> workers that tiny arthropods matter. They patrol fungal films, recycle bat guano, and feed larger cave invertebrates, weaving subterranean food webs every bit as intricate as those above ground. 



Protecting the darkness, therefore, protects an entire hidden branch of the Korean biosphere, one dragon‑jawed pseudoscorpion at a time.



The study is published in <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0325375">PLOS One</a>.



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'Dragon pseudoscorpions' discovered living in caves have no fangs or eyes

Four tiny predators were hiding in South Korea’s limestone and...

You’ve seen them on shirts, in documentaries, and maybe jumping at a theme park. They look bold and sound fierce. But orcas, also called killer whales, aren’t what the name suggests. They’re smart, social, and loyal. Every year on July 14, we celebrate World Orca Day.



It started in New Zealand. A young orca got stuck in shallow water. Locals worked together to help him return to the sea. That rescue turned into something bigger. Now, people around the world use this day to honor <a href="https://www.earth.com/news/orcas-have-hunting-and-eating-habits-that-we-never-imagined/">orcas</a> - not only celebrating their strength but also highlighting the challenges they face.



While some orcas are thriving, many are struggling. They face pollution, food shortages, and in some cases, captivity in tanks. World Orca Day presents an opportunity to learn about the real challenges they endure.



<h2 class="wp-block-heading" id="h-orcas-live-in-pods-and-pass-on-skills">Orcas live in pods and pass on skills</h2>



Orcas aren’t whales - they’re actually <a href="https://www.earth.com/news/why-are-killer-whales-struggling-to-survive-in-the-pacific/">dolphins</a> that live in social groups called pods. Every pod has its unique way of communicating. Some feed exclusively on fish, others hunt seals, and a few even pursue sharks. Each group follows its own distinct hunting strategy.



Orcas learn how to hunt from each other. Young ones watch the adults. They copy what they see, and then get better at it. Some pods chase fish into tight balls. Others slide onto beaches to grab seals. These skills don’t come from instinct - they’re passed down like family recipes.



Orcas stick together. Mothers lead, sons often stay for life, and grandmothers play a big role. They know the best places to find food and guide the group with memory and experience. These pods aren’t random groups - they are families.



<h2 class="wp-block-heading" id="h-awareness-on-world-orca-day">Awareness on World Orca Day </h2>



The <a href="https://www.earth.com/news/prehistoric-marine-reptiles-would-have-eaten-killer-whales-as-snacks/">ocean</a> has gotten louder due to ships, drills, sonar. It’s equal to trying to talk in traffic. Orcas use sound to hunt and stay close. Ocean noise messes that up.



Food is another problem. Some orcas depend on salmon, but in some places, these fish are disappearing. Less food means weaker orcas, affecting moms, calves, and the whole pod.



Pollution adds to the stress. Orcas store fat. When they don’t eat enough, they burn that fat for energy. That’s when stored toxins enter the bloodstream, impacting their health and survival.



Some orca populations are shrinking. They can’t bounce back if the ocean stays loud and empty.



<h2 class="wp-block-heading" id="h-tanks-are-not-healthy-homes">Tanks are not healthy homes</h2>



Captive orcas live in marine parks. They spend years in tanks that are too small and restrictive.



<a href="https://www.earth.com/news/photographer-captures-killer-whales-wearing-fish-hats/">Orcas</a> kept in tanks often suffer from illness. They may grind their teeth and display unusual behaviors, and they tend to have shorter lifespans than their wild counterparts. 



While some parks continue to feature them in shows, this is more for entertainment than genuine education.



A few places have banned <a href="https://savedolphins.eii.org/campaigns/fow">orca captivity</a>. Others still allow it. World Orca Day reminds people that wild animals belong in the wild. Tanks don’t offer a healthy life.



<h2 class="wp-block-heading" id="h-world-orca-day-inspires-action">World Orca Day inspires action</h2>



To help protect orcas, you can start with the basics. Learn what makes them unique and share those facts with others. Stay away from parks that keep orcas in tanks. Choose brands that care about the ocean.



You don’t need to live near the coast to make a difference. You can watch orcas through live cams, read their stories, and talk about them. You can join a cleanup in your area or support groups working to protect marine life. Every small step counts.



On World Orca Day, schools and science centers often join the effort. Kids ask questions. Teachers explore ocean life. Artists and researchers also get involved. And you can too, in whatever way fits you best.



<h2 class="wp-block-heading" id="h-why-this-day-still-matters">Why this day still matters</h2>



Orcas play a big role in the ocean. They help keep balance in marine food webs. When they suffer, the whole system shifts. They’re not just animals. They’re indicators of ocean health.



World Orca Day calls on us to care - to recognize how our actions impact the ocean. Orcas don’t seek applause; they need clean waters, plenty of food, and peaceful places to raise their young.



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World Orca Day 2025: Saving the ocean's top predators

You’ve seen them on shirts, in documentaries, and maybe jumping...

Fish have voices, and the sea is never silent. From croaks that ricochet through mangroves to deep‑sea booms, these conversations guide courtship, navigation, and survival.



A new analysis from <a href="https://www.sfu.ca/" target="_blank" rel="noreferrer noopener">Simon Fraser University</a> shows that Canada’s flagship conservation policies almost never recognize those <a href="https://www.earth.com/news/small-fish-species-are-the-big-catch-of-the-future/">voices</a>, leaving vital acoustic habitats unguarded. 



Marine ecologist <a href="https://www.sfu.ca/postdoctoral-fellows/profiles/kieran-cox.html" target="_blank" rel="noreferrer noopener">Kieran Cox</a> of Simon Fraser University co‑authored the study that sifted through two decades of federal paperwork.



<h2 class="wp-block-heading" id="h-fish-use-sound-to-survive-and-reproduce">Fish use sound to survive and reproduce</h2>



More than 1,000 known fish species are <a href="https://www.nature.com/articles/s41597-023-02745-4" target="_blank" rel="noreferrer noopener">soniferous</a>, meaning they deliberately produce sound to communicate, and hundreds more are suspected to do the same. Male toadfish drone like idling motorcycles, while haddock tick and grouper boom, each signal tuned to species‑specific ears.



“A male <a href="https://www.earth.com/news/ancient-fish-bones-reveal-clues-about-the-evolution-of-eating/">fish</a> might hum or sing to attract their mates, and the longer his song, or the louder it is, the more eggs he will get from females,” explained Cox. 



Atlantic cod <a href="https://academic.oup.com/tafs/article/135/2/529/7887937" target="_blank" rel="noreferrer noopener">Gadus morhua</a> grunt through swim‑bladder muscles during spawning, and researchers have tracked entire aggregations by listening to those calls.



<h2 class="wp-block-heading" id="h-ocean-noise-drowns-out-fish-voices">Ocean noise drowns out fish voices</h2>



The <a href="https://www.science.org/doi/10.1126/science.aba4658" target="_blank" rel="noreferrer noopener">ocean soundscape</a>, the mix of biological, physical, and human noises filling the water, has changed faster than any other habitat feature in recent decades. 



Ship engines, seismic air guns, and pile drivers add low‑frequency roar that travels farther than light or chemicals, masking the fine‑tuned signals fish depend on.



Most of this din comes from <a href="https://wwwcdn.imo.org/localresources/en/OurWork/PartnershipsProjects/Documents/GloNoise-Library/MEPC.1-Circ.833-7April2014.pdf" target="_blank" rel="noreferrer noopener">underwater radiated noise</a> generated when propeller bubbles collapse and machinery vibrates the hull. As depth increases and daylight fades, sound replaces vision, so the risk rises for deep‑water species that have no other way to find mates or food.



<h2 class="wp-block-heading" id="h-conservation-laws-ignore-acoustic-habitats">Conservation laws ignore acoustic habitats</h2>



<a href="https://www.sciencedirect.com/science/article/pii/S0006320725003763" target="_blank" rel="noreferrer noopener">COSEWIC</a>, the expert panel that advises Ottawa on endangered wildlife, acknowledged fish sound production in just one assessment out of 204. Neither of the 56 recovery strategies drafted under <a href="https://laws.justice.gc.ca/eng/acts/s-15.3/" target="_blank" rel="noreferrer noopener">SARA</a>, Canada’s endangered‑species law, mentioned soundscapes or noise threats.



Anthropogenic noise has <a href="https://www.science.org/doi/10.1126/science.aah4783" target="_blank" rel="noreferrer noopener">doubled</a> background sound levels in more than half of U.S. protected areas, hinting at the scale of the problem in Canadian waters as well. 



When noise blocks communication, the effect mirrors habitat loss, shrinking a <a href="https://www.earth.com/news/fish-dont-rest-while-hovering-its-actually-hard-work/">fish</a>’s functional living space even though the water looks unchanged.



<h2 class="wp-block-heading" id="h-learning-from-the-whales">Learning from the whales</h2>



Regulators already protect communication spaces for southern resident <a href="https://www.dfo-mpo.gc.ca/species-especes/publications/mammals-mammiferes/whalereview-revuebaleine/review-revue/killerwhale-epaulard/index-eng.html" target="_blank" rel="noreferrer noopener">killer whales</a>, setting vessel speed limits and buffer zones in the Salish Sea. During voluntary slow‑down trials, <a href="https://www.sciencedirect.com/science/article/pii/S0025326X21010109" target="_blank" rel="noreferrer noopener">quieter ships</a> raised successful foraging dives by the whales, proving that less noise can yield instant biological payoffs.



Fish biologists argue the same principle should apply below the whales, because many coral, seagrass, and deep‑sea communities are built on acoustic cues. 



The International Maritime Organization’s revised <a href="https://wwwcdn.imo.org/localresources/en/Documents/MEPC.1-Circ.906%20-%20Revised%20Guidelines%20For%20The%20Reduction%20Of%20Underwater%20Radiated%20NoiseFrom%20Shipping%20To%20Address...%20%28Secretariat%29.pdf" target="_blank" rel="noreferrer noopener">guidelines</a> outline hull forms, propeller tweaks, and resilient engine mounts that slash cavitation clatter at the design stage.



For existing fleets, slower speeds remain the <a href="https://www.sciencedirect.com/science/article/pii/S0025326X21013357" target="_blank" rel="noreferrer noopener">quickest fix</a>, trimming hull noise in minutes and saving fuel at the same time. On land, urban planners already impose airport curfews; similar acoustic zoning could shield key spawning refuges from seismic blasts.



<h2 class="wp-block-heading" id="h-fish-voices-must-be-included-in-planning">Fish voices must be included in planning</h2>



<a href="https://sites.google.com/site/ecoacousticssociety" target="_blank" rel="noreferrer noopener">Ecoacoustics</a>, the cross‑disciplinary science of environmental sound, now lets managers deploy autonomous recorders that log fish choruses year‑round with little labor. 



Cox and his team want Ottawa to add acoustics to every new status report, a change that would trigger legal duties to weigh noise limits before approving coastal developments.



“These three aspects of sound create different types of marine noise pollution, and each kind of noise pollution poses potential risks to marine species, from whales to fish to crustaceans,” said Kiara Kattler, who led the analysis in Isabelle Côté’s <a href="https://tmel.wordpress.com/" target="_blank" rel="noreferrer noopener">lab</a>.



If policy follows the evidence, tomorrow’s endangered‑species plans could include quiet hours, ship‑route changes, and protected “singing grounds” for fish.



<h2 class="wp-block-heading" id="h-what-policymakers-can-do-now">What policymakers can do now</h2>



Fisheries managers don’t have to wait for more studies to take action. Passive acoustic monitoring gear is already cheap, easy to deploy, and able to track seasonal behavior in many key species. 



Adding simple guidance on soniferous species to existing review checklists could prevent new development from degrading acoustic <a href="https://www.earth.com/news/how-alternative-seafood-can-help-save-our-oceans/">habitats</a> by accident.



Acoustic degradation doesn’t only affect fish. Crustaceans, cephalopods, and even coral larvae also use sound to find mates or settle in reef habitats, which means entire ecosystems could be thrown off balance. 



By integrating sound into conservation policies, agencies could protect dozens of marine species at once without needing separate rules for each.



The study is published in the journal <a href="https://www.sciencedirect.com/science/article/pii/S0006320725003763?dgcid=coauthor" target="_blank" rel="noreferrer noopener">Biological Conservation</a>.



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Fish have voices but conservation policies ignore them

Fish have voices, and the sea is never silent. From...

The Earth spins steadily, but not without a wobble. While we imagine the North and South Poles as fixed points, they’re not exactly anchored. Over time, they shift slightly, influenced by how mass is distributed across the globe. 



Ice sheets melt, tectonic plates shift, and oceans swell. But now, researchers have revealed that humans, through dam building, have also nudged the planet’s spin ever so slightly.



In a quiet but measurable way, our thirst for water control and hydroelectric energy has shifted the Earth's poles. From the earliest major dams in the 19th century to the massive reservoirs constructed in Asia and Africa during the 20th century, the <a href="https://www.earth.com/news/climate-change-is-now-impacting-earths-rotation/">effect</a> has grown stronger. 



According to a study published in the journal Geophysical Research Letters, this phenomenon has moved Earth’s rotational axis by more than a meter (3.3 feet) since 1835.



<h2 class="wp-block-heading" id="h-dam-building-shifts-earth-s-poles">Dam building shifts Earth’s poles</h2>



True polar wander refers to the shifting of <a href="https://www.earth.com/news/magnetic-north-pole-is-moving-faster-than-ever-as-it-races-toward-russia/">Earth</a>’s solid outer shell relative to its spin axis. This motion occurs when mass on the planet’s surface moves around. 



Think of Earth like a spinning basketball. Place a lump of clay on one side, and the ball shifts slightly to balance the extra weight. When this happens on Earth, the solid crust adjusts its position, moving relative to the axis of rotation. The poles then pass through new locations on the surface.



Traditionally, this phenomenon has been linked to natural processes like glacial melting. But the recent study by Natasha Valencic and her team at <a href="https://www.harvard.edu" target="_blank" rel="noreferrer noopener">Harvard University</a> shows that human activity, specifically water impoundment from dam construction, has become another significant contributor. 



The findings suggest that this artificial redistribution of mass has created a measurable shift in the Earth’s pole positions.



“As we trap water behind dams, not only does it remove water from the oceans, thus leading to a global sea level fall, it also distributes mass in a different way around the world,” said Valencic. That mass, once fluid and ocean-bound, is now stored in still reservoirs scattered across continents.



<h2 class="wp-block-heading" id="h-earth-s-poles-moved-in-two-phases">Earth’s poles moved in two phases</h2>



Using data from the Global Reservoir and Dam (GRanD) database, the researchers mapped the water storage of 6,862 artificial reservoirs from 1835 to 2011. The dam analysis revealed a striking, non-linear shift in the Earth’s poles. 



From 1835 to 1954, dam building focused heavily in North America and Europe. This caused the North Pole to move about eight inches toward 103.4°E, a direction passing through Russia and parts of Asia.



After 1954, the pattern of dam construction changed. Major projects emerged across East Africa and Asia. As a result, the pole reversed direction, moving 22.5 inches toward −117.5°E, roughly through the western United States and into the South Pacific. 



These changes did not follow a smooth path. The polar motion was highly variable, influenced by the size and location of dams being built over time.



Across the entire study period, the poles shifted about 44.6 inches. Notably, 40.9 inches of that motion occurred during the 20th century. This finding suggests that modern infrastructure, rather than long-term natural <a href="https://www.earth.com/news/this-is-what-the-total-collapse-of-the-earths-magnetic-field-sounded-like-41000-years-ago/">processes</a> alone, has become a key factor in Earth's orientation.



<h2 class="wp-block-heading" id="h-dams-and-earth-s-pole-positions">Dams and Earth's pole positions</h2>



To track these subtle shifts, the team used a detailed physical model. They combined gravitationally self-consistent sea level theory with equations for rotational stability. 



The researchers accounted for how Earth’s crust responds elastically to mass changes, and how these changes, in turn, influence Earth’s spin.



The Earth model used, known as PREM (Preliminary Reference Earth Model), includes variations in Earth’s density and elasticity. The team also incorporated seepage, the loss of stored water into surrounding soils, using a parameterization method from earlier work by Chao et al. (2008). 



Despite excluding about 28 percent of the <a href="https://www.earth.com/news/earths-magnetic-field-is-shifting-and-putting-navigation-at-risk/">global</a> impoundment volume, mainly from smaller dams, the results remained consistent. 



The missing volume came mostly from minor reservoirs, each contributing less than 0.024 cubic miles, and these had minimal influence on the final polar calculations.



To test the significance of these smaller dams, the team plotted how pole position changed with each added reservoir. After about 6,000 of the largest were included, the results stabilized. This confirmed that the many small, excluded dams had negligible overall effect.



<h2 class="wp-block-heading" id="h-dam-water-storage-and-sea-levels">Dam water storage and sea levels</h2>



Global sea levels are rising today, but during the 20th century, the creation of reservoirs temporarily offset this trend. The researchers found that the 6,862 dams in their study led to a sea level drop of 0.86 inches between 1900 and 2011.



This artificial dip matters. While it’s small compared to the rise caused by melting glaciers and warming oceans, it complicates calculations. 



“Depending on where you place dams and reservoirs, the geometry of sea level rise will change. That’s another thing we need to consider, because these changes can be pretty large, pretty significant," said Valencic.



In the first half of the 20th century, the mean polar motion rate from impoundment was about 0.12 inches per year. 



In the second half, it rose to 0.37 inches per year, a threefold increase. The pole's changing pace mirrors the rapid expansion of dam building after 1950.



<h2 class="wp-block-heading" id="h-revisiting-old-assumptions">Revisiting old assumptions </h2>



Previous studies underestimated the effect of dam-induced polar wander. One earlier estimate in 2008 suggested a mean movement of −0.06 inches per year in the east direction and −0.31 inches per year northward across the 20th century.



But Valencic’s team found it was actually −0.12 inches per year and −0.09 inches per year, respectively. This difference matters because it rebalances the budget of polar motion. 



Scientists trying to understand how much glaciers, groundwater, or ocean changes contribute to Earth's spin now have to subtract out the dam effect. Without this correction, estimates about ice loss and sea level rise remain incomplete.



Interestingly, the influence of dam building didn’t act alone in shifting Earth's poles. The researchers also modeled how the oceans responded to displaced water. 



While water impoundment dominated the first half of the century, the second half saw both dam storage and ocean mass redistribution playing nearly equal roles in shaping Earth’s polar path.



<h2 class="wp-block-heading" id="h-subtle-shift-in-earth-s-poles">Subtle shift in Earth's poles</h2>



This study began as a classroom project at Harvard but quickly grew into a deeper investigation of Earth’s shifting balance. It reveals that something as mundane as a dam, one of civilization’s most common tools, has reshaped the geography of our spinning planet.



The pole has not leapt across continents. It has crept, step by engineered step, with every new concrete wall holding back a river. While not disastrous on its own, this shift reveals a truth: our actions reach farther than we often imagine.



Every dam, every floodgate, becomes part of the Earth’s momentum. What we store on land doesn’t just change rivers. It nudges Earth’s rotation, redistributes the weight of water, and contributes silently to a planet that, while spinning, is never truly still.



The study is published in the journal <a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025GL115468" target="_blank" rel="noreferrer noopener">Geophysical Research Letters</a>.



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Dams built by humans have shifted Earth’s poles

The Earth spins steadily, but not without a wobble. While...

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Adjustable Toilet Flapper

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The "All-American" is the best among home pressure canners. With proper care it will last a lifetime. Made in the USA since 1930. Read more Overview Only All-American Pressure Cookers/Canner feature an exclusive, precision machined "metal-to-metal" sealing system. Positive action clamping locks align the cover to the base, forming a steam-tight seal. At the same time, this metal-to-metal seal automatically permits venting under unusual pressure conditions, providing an extra margin of safety over conventional rubber or composition gasket cookers. The All-American Pressure Cooker/Canner is, first and foremost, a canner. It is large and heavy-cast for processing larger quantities of food per load. The USDA recommends pressure canning as the only safe way to can meat, fish, poultry and vegetables. "Pressure cookers" are not recommended for canning because a fully loaded canner takes a longer time for heating and cooling. This time is taken into account when determining processing times in standard canning timetables. Features & Benefits: Crafted of the finest hand cast aluminum Stay-cool bakelite top handle Geared steam gauge Pressure regulator weight with settings of 5, 10 and 15 psi Smooth, easy to clean satin finish Exclusive metal-to-metal seal - no gaskets to crack, burn, replace or clean Double thickness edges for additional protection on points of heaviest wear Automatic overpressure release Includes canning rack, instructions & recipe book Available in 6 sizes Made in the USA since 1930 Specifications for Model 910: Capacity - 10.5 Quarts (Liquid), 4 Quart Jars, 7 Pint Jars* Inside diameter - 10 1/4 inches Inside Height - 7 3/4 inches Overall Height - 12 inches Weight - 11.5 pounds Includes 1 rack *Jar capacities based on standard Mason jar sizes All-American Pressure Cooker/Canners are intended for home use applications. Models 910, 915, 921 and 925 are suitable for use on newer glass/flat top ranges. We recommend verifying weight restrictions with your stove manufacturer. Larger models 930 and 941 are heavy and not suitable for glass top ranges. "We bought an All-American Pressure Canner (Model 921) over 30 years ago, and have used it exclusively for all our canning. It is still as good as new." Greg Seaman, Founder, Eartheasy.com

All-American Pressure Canner/Cooker - 10.5 quart

The "All-American" is the best among home pressure canners. With...

The "All-American" is the best among home food production pressure canners. With proper care it will last a lifetime. Made in the USA since 1930. Read more Overview Only All-American Pressure Cookers/Canner feature an exclusive, precision machined "metal-to-metal" sealing system. Positive action clamping locks align the cover to the base, forming a steam-tight seal. At the same time, this metal-to-metal seal automatically permits venting under unusual pressure conditions, providing an extra margin of safety over conventional rubber or composition gasket cookers. The All-American Pressure Cooker/Canner is, first and foremost, a canner. It is large and heavy-cast for processing larger quantities of food per load. The USDA recommends pressure canning as the only safe way to can meat, fish, poultry and vegetables. "Pressure cookers" are not recommended for canning because a fully loaded canner takes a longer time for heating and cooling. This time is taken into account when determining processing times in standard canning timetables. Features & Benefits: Crafted of the finest hand cast aluminum Stay-cool bakelite top handle Geared steam gauge Pressure regulator weight with settings of 5, 10 and 15 psi Smooth, easy to clean satin finish Exclusive metal-to-metal seal - no gaskets to crack, burn, replace or clean Double thickness edges for additional protection on points of heaviest wear Automatic overpressure release Includes canning rack and instructions Available in 6 sizes Made in the USA since 1930 Specifications for Model 915: Capacity - 15 1/2 Quarts (Liquid), 7 Quart Jars, 10 Pint Jars* Inside diameter - 12 5/8 inches Inside Height - 7 3/4 inches Overall Height - 12.5 inches Weight - 15 pounds Includes 1 rack *Jar capacities based on standard Mason jar sizes. All-American Pressure Cooker/Canners are intended for home use applications. Models 910, 915, 921 and 925 are suitable for use on newer glass/flat top ranges. We recommend verifying weight restrictions with your stove manufacturer. Larger models 930 and 941 are heavy and not suitable for glass top ranges. "We bought an All-American Pressure Canner (Model 921) over 30 years ago, and have used it exclusively for all our canning. It is still as good as new." Greg Seaman, Founder, Eartheasy.com

All-American Pressure Canner/Cooker - 15.5 quart

The "All-American" is the best among home food production pressure...

The "All-American" is the best among home food production pressure canners. With proper care it will last a lifetime, which is why we recommend getting the best. Made in the USA since 1930. Read more Overview Only All-American Pressure Cookers/Canner feature an exclusive, precision machined "metal-to-metal" sealing system. Positive action clamping locks align the cover to the base, forming a steam-tight seal. At the same time, this metal-to-metal seal automatically permits venting under unusual pressure conditions, providing an extra margin of safety over conventional rubber or composition gasket cookers. The All-American Pressure Cooker/Canner is, first and foremost, a canner. It is large and heavy-cast for processing larger quantities of food per load. The USDA recommends pressure canning as the only safe way to can meat, fish, poultry and vegetables. "Pressure cookers" are not recommended for canning because a fully loaded canner takes a longer time for heating and cooling. This time is taken into account when determining processing times in standard canning timetables. Features & Benefits: Crafted of the finest hand cast aluminum Stay-cool bakelite top handle Geared steam gauge Pressure regulator weight with settings of 5, 10 and 15 psi Smooth, easy to clean satin finish Exclusive metal-to-metal seal - no gaskets to crack, burn, replace or clean Double thickness edges for additional protection on points of heaviest wear Automatic overpressure release Includes canning racks and instructions Available in 6 sizes Made in the USA since 1930 Specifications for Model 921: Capacity - 21 1/2 Quarts (Liquid), 7 Quart Jars, 19 Pint Jars Inside diameter - 12 5/8 inches Inside Height - 10 1/2 inches Overall Height - 16 inches Weight - 17.75 pounds Includes 2 racks *Jar capacities based on standard Mason jar sizes. All-American Pressure Cooker/Canners are intended for home use applications. Models 910, 915, 921 and 925 are suitable for use on newer glass/flat top ranges. We recommend verifying weight restrictions with your stove manufacturer. Larger models 930 and 941 are heavy and not suitable for glass top ranges. "We bought an All-American Pressure Canner (Model 921) over 30 years ago, and have used it exclusively for all our canning. It is still as good as new." Greg Seaman, Founder, Eartheasy.com

All-American Pressure Canner/Cooker - 21.5 quart

The "All-American" is the best among home food production pressure canners. With proper care it will last a lifetime. Made in the USA since 1930. Read more Overview Only All-American Pressure Cookers/Canner feature an exclusive, precision machined "metal-to-metal" sealing system. Positive action clamping locks align the cover to the base, forming a steam-tight seal. At the same time, this metal-to-metal seal automatically permits venting under unusual pressure conditions, providing an extra margin of safety over conventional rubber or composition gasket cookers. The All-American Pressure Cooker/Canner is, first and foremost, a canner. It is large and heavy-cast for processing larger quantities of food per load. The USDA recommends pressure canning as the only safe way to can meat, fish, poultry and vegetables. "Pressure cookers" are not recommended for canning because a fully loaded canner takes a longer time for heating and cooling. This time is taken into account when determining processing times in standard canning timetables. Features & Benefits: Crafted of the finest hand cast aluminum Stay-cool bakelite top handle Geared steam gauge Pressure regulator weight with settings of 5, 10 and 15 psi Smooth, easy to clean satin finish Exclusive metal-to-metal seal - no gaskets to crack, burn, replace or clean Double thickness edges for additional protection on points of heaviest wear Automatic overpressure release Includes canning racks and instructions Available in 6 sizes Made in the USA since 1930 Specifications for Model 925: Capacity - 25 Quarts (Liquid), 7 Quart Jars, 19 Pint Jars Inside diameter - 12 5/8 inches Inside Height - 12 1/4 inches Overall Height - 16 3/4 inches Weight - 18.25 pounds Includes 2 racks *Jar capacities based on standard Mason jar sizes. All-American Pressure Cooker/Canners are intended for home use applications. Models 910, 915, 921 and 925 are suitable for use on newer glass/flat top ranges. We recommend verifying weight restrictions with your stove manufacturer. Larger models 930 and 941 are heavy and not suitable for glass top ranges. "We bought an All-American Pressure Canner (Model 921) over 30 years ago, and have used it exclusively for all our canning. It is still as good as new." Greg Seaman, Founder, Eartheasy.com