Wounds may trigger 'aged' cells within hours, reshaping how senescence starts
Cells can enter senescence within minutes to hours after injury, using pre-existing mRNA to rapidly produce p21 protein, independent of new gene transcription. This early senescence actively coordinates wound healing by releasing signaling molecules and guiding cell migration, but is beneficial only during a narrow time window and is eliminated after healing. Persistent senescent cells are linked to age-related diseases.

Karla Valdivieso et al, Transcription-independent induction of rapid-onset senescence is integral to healing, Nature Cell Biology (2026). DOI: 10.1038/s41556-026-01948-2

The Y chromosome is home to surprising jumping genes

The humble Y chromosome may be the smallest chromosome in the mammalian genome (and getting even smaller), but it is mighty: Genes on the Y chromosome are critical for fertility in males.

In a new study in the journal Current Biology, researchers have studied deer mice to outline how the Y chromosome defends itself against decay by acquiring gene families, holding its own to maintain fertility.
A gene family named Phf8y was identified on the Y chromosome of deer mice, originating from the X-linked Phf8 gene via transposable element-mediated duplication. This represents a rare case of a gene moving from the X chromosome to an autosome and then to the Y chromosome. Such gene acquisitions may help the Y chromosome maintain essential functions for male fertility and contribute to the evolutionary stability of sex ratios.

Autosomes are all of the chromosomes that aren't the sex chromosomes. However, the Y chromosome is often thought of as a place where genes go to die because its genes don't recombine.
In this study, researchers discovered a gene family, which they named Phf8y, that bucked this trend, hopping to the Y and duplicating itself.
It's a unique pattern that they didn't expect—having a gene move from the X chromosome to an autosome to the Y chromosome.
What's driving the process? In the production of sperm, the X chromosome from the maternal side and the Y chromosome from the paternal side result in a sperm cell that has either an X or Y chromosome.

During this period, the X serves as a sort of autosome for genes important for viability and spermatogenesis, Mueller explains.
But since males carry just one X, an alternative method arose evolutionarily to provide a way to back up important genes for creating sperm.
It's like having your own clone around who can jump in when you've gone on vacation.
There are genes that copy themselves, called transposable elements. They hide out in our genome and are activated on rare occasions. In fact, these so-called jumping genes make up half of the human genome.

The team discovered that the deer mouse Phf8y on the Y chromosome is derived from the X-linked Phf8, apparently having hijacked the transposable element machinery to make an extra copy of itself.

What Phf8y is doing is still a mystery.

The team speculates that this gene on the Y chromosome is involved in chromatin packing, or how DNA is packaged, and could confer an edge to Y-bearing sperm to compete with X-bearing sperm.

Previous studies in house mice have revealed genes that share similar features to Phf8y and are in an X–Y arms race.

Ivan F. Mier et al, An X-to-autosome-to-Y chromosome amplified retrogene family functions in spermatids, Current Biology (2026). DOI: 10.1016/j.cub.2026.04.045

some chikungunya virus infections may turn chronic

Chikungunya virus, which is transmitted to people by infected Aedes mosquitoes and characterized by high fever and intense joint swelling and pain, has made a resurgence in many countries around the world in recent years.

Researchers estimate that about half of people infected with chikungunya virus will progress to a chronic form of the disease and experience relapsing arthralgia and arthritis that can span years and currently has no treatment.
Chikungunya virus can persist in joint-associated macrophages, which act as reservoirs, leading to chronic joint pain and inflammation in about half of infected individuals. Advanced sequencing techniques identified these macrophages as harbouring viral RNA, and antiviral treatment targeting viral replication reduced chronic inflammation, indicating persistent infection in these cells drives chronic symptoms.

Kristen M. Zarrella et al, Chikungunya virus persists in joint-associated macrophages and promotes chronic disease in mice, Nature Microbiology (2026). DOI: 10.1038/s41564-026-02303-9

One-time gene editing treatment lowers 'bad' cholesterol by up to 62%
A single infusion of the gene editing therapy VERVE-102 reduced LDL cholesterol by up to 62% in adults with inherited high cholesterol or premature coronary artery disease, with effects lasting up to 18 months. No serious adverse events were observed at the highest dose, and only mild, transient infusion reactions and liver test changes occurred. Larger studies are ongoing to confirm safety and efficacy.

Scott B. Vafai et al, In Vivo Base Editing of PCSK9 with VERVE-102 for Hypercholesterolemia, New England Journal of Medicine (2026). DOI: 10.1056/nejmoa2601283

A common food compound may hold the key to shutting down leaky gut damage

When the intestinal lining breaks down, harmful gut bacterial antigens can slip into the bloodstream alongside nutrients. This breach in the gut's protective barrier, known as "leaky gut," is more than a digestive issue—it's a sign of inflammatory bowel disease (IBD) and has been increasingly linked to a number of chronic conditions.
A team of researchers has uncovered a key mechanism underlying leaky gut and identified a promising and natural way to repair it. And a potential solution is already in many of the foods we eat every day.

In a study published in the journal Nature Communications, the team shares how phytic acid (or InsP6), a natural compound found in whole grains, beans, lentils, nuts, and seeds, plays an important role in maintaining the integrity of the intestinal barrier.

Phytic acid is something many people already consume daily, especially in plant-rich diets.It's beyond just a dietary component; it also functions as a biologically active molecule that supports gut health.
Phytic acid (InsP6), a compound found in whole grains, beans, lentils, nuts, and seeds, directly activates histone deacetylase 3 (HDAC3), a regulator essential for maintaining intestinal barrier integrity. This mechanism protects against gut barrier breakdown and inflammation associated with leaky gut and inflammatory bowel disease, suggesting potential for targeted supplementation therapies.

Sujan Chatterjee et al, Phytic acid (InsP6) activates HDAC3 epigenetic axis to maintain intestinal barrier function, Nature Communications (2026). DOI: 10.1038/s41467-026-68994-0

Exploding immune cells that kill surrounding tissue

 Scientists have discovered a new type of immune cell that kills surrounding cells via explosion—a cellular detonation so fast and complete that the cell vanishes within minutes, leaving no trace behind. This discovery comes from an unlikely source: planarian flatworms. These aquatic, slithering pancake versions of worms are famous for their ability to survive dismemberment and grow whole new organisms from the sliced-up segments of their formerly unified body. Understanding how these flatworms' immune systems have managed to endure for hundreds of millions of years could hold important insights for modern medicine.

In a new study published June 2 in Cell, the team describes the discovery and names these new cells "ruptoblasts" for their explosive response to a certain hormone.

A postdoctoral researcher first observed these cells while investigating the long-standing mystery in flatworm biology of whether or not they can tell the difference between their own tissues and those of another individual. To find out, she longitudinally sliced the flatworms and fused them together with a separate worm. Although adept at regrowing their own tissues, the researcher noted that these "Frankenstein" worms rejected halves of other worms, similar to how a human body may reject an organ transplant from a donor.

Unlike humans, however, a different cellular defense mechanism sprang into action.

It's this huge inflammatory response. Like there's a fire and an alarm goes off, and the cells just blow up.

Some mammalian cells and bacteria may also do an explosive sort of cell death, but the timescale is really long. They are exploding, but it's more like pores that slowly leak things out over the course of several hours. Ruptosis happens within seconds to minutes.

In a matchup against E. coli bacteria, human kidney cells, and mouse blood cells, ruptoblasts destroyed all three. Yet the authors noted that cell fatalities were limited to the immediate area of the explosion and did not trigger any sort of chain reaction or lingering toxicity. This localized effect holds promise for targeted treatments of bacterial infections or tumours.

Another characteristic that sets ruptoblasts apart from other immune cells, like T-cells or neutrophils, is the fact that they are glandular cells rather than hematopoietic cells, or blood cells produced in the bone marrow. The ruptoblasts seem to figure out a way to amplify their secretion machinery to suddenly and violently release cytotoxic substances in response to activin. A sharp increase in calcium from the endoplasmic reticulum within the ruptoblast helps facilitate the ruptosis.

In searching for these cells in other organisms,  the researchers discovered that they only appear in basal bilaterians like the flatworms, which points to these cells having early evolutionary origins.

The reason these cells were filtered out of modern vertebrate immune systems could be because vertebrates lack the ability to repair other cells after ruptosis occurs, unlike flatworms that are rich in stem cells.

Explosive cytotoxicity of ruptoblasts bridges hormone surveillance and immune defense, Cell (2026). DOI: 10.1016/j.cell.2026.05.008. www.cell.com/cell/fulltext/S0092-8674(26)00567-2

Cutting a photon in two creates an infinite swarm of particles
Attempting to split a single photon using a fast optical shutter does not yield two smaller photons but instead generates a quantum superposition containing infinitely many photons due to disturbances in the electromagnetic field's quantum fluctuations. Locally, the system appears unchanged, but globally, the quantum state becomes highly complex, illustrating the non-classical behaviour of quantum particles.

Isak Cecil Onsager Rukan et al, Truncated photon, Physical Review Letters (2026). DOI: 10.1103/94pm-hp34. On arXiv: arxiv.org/abs/2510.21636

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Embryonic tissues can behave like fluids or solids to reshape cell fate signals Tissue rigidity in embryonic development is actively regulated by cell-cell adhesion, not cell density, enabling transitions between fluid-like and solid-like states. Increased adhesion induces tissue stiffening, which restricts morphogen diffusion, spatially localizing developmental signals such as Nodal and influencing cell fate. Morphogen signaling can also enhance local tissue rigidity, creating a feedback loop between mechanical and biochemical processes.

Rustarazo-Calvo, L., et al. Adhesion-driven rigidity transition decoupled from density-driven jamming triggers epithelial organization in embryonic tissues., Nature Physics (2026). DOI: 10.1038/s41567-026-03276-6

Camilla Autorino et al, Tissue rigidity phase transition shapes morphogen gradients, Nature Cell Biology (2026). DOI: 10.1038/s41556-026-01954-4

UN warns world to prepare for El Nino extreme weather

There is an 80% probability of El Niño developing between June and August, with a likelihood near or above 90% by November. El Niño is expected to cause above-normal global temperatures and increase the risk of extreme weather events, including drought, heavy rainfall, and heat waves. Climate change does not increase El Niño frequency or intensity but can amplify its impacts. Regional forecasts indicate drier and warmer conditions in parts of Africa, South Asia, and Central America.

News Agencies

A small amount of rare earth metal shapes the environmental impact of magnets
Dysprosium, though comprising only 1–8% of permanent magnets used in electric vehicles and wind turbines, accounts for up to 78% of their environmental impact and 44% of raw material costs due to energy- and chemical-intensive extraction and separation processes. Reducing dysprosium content through improved material efficiency or alternative technologies could significantly lower environmental and economic burdens while decreasing supply chain vulnerability.

Stellina Samuel et al, Mitigating the disproportionate environmental impacts and costs of dysprosium in Nd-Fe-B magnets through material efficiency, Sustainable Production and Consumption (2026). DOI: 10.1016/j.spc.2026.04.006

Single cell transforms into cannibalistic 'supergiant,' swallowing its clones whole

Researchers have discovered a microscopic organism that can transform into a cannibalistic "supergiant" that drastically changes size, shape, and behavior, and abandons filter-feeding to hunt and consume their genetically identical relatives.
Euplotes gigatrox, a newly identified ciliate, can transform from a filter-feeding cell into a larger, cannibalistic "supergiant" that preys on its clonal relatives. This transformation represents a distinct, transcriptionally regulated developmental stage, with altered morphology, behavior, and gene expression. Supergiant formation is rare, environmentally triggered, and may represent a bet-hedging strategy.
The work demonstrates how single-celled organisms are capable of complex, regulated development, which scientists have largely only studied in multicellular animals.
In clonal populations of these organisms where every cell shares the same DNA, a small number of cells can spontaneously develop into supergiants more than twice the length of normal cells, with a broader body shape and a larger mouth.

Rather than filter-feeding on bacteria as normal cells do, supergiants become raptorial predators, running over smaller clonal relatives to capture and swallow them whole at a rate of roughly one prey every 10 minutes.

Ben T. Larson et al, Regulated development of cannibalistic supergiant cells in the ciliate Euplotes gigatrox, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2606891123. On bioRxiv: www.biorxiv.org/content/10.110 … /2025.08.19.671124v2

The hum that only a few can perceive: Potential sources of a low-frequency sound

Some people occasionally hear a low buzzing or humming sound that doesn't have a clear source. An estimated 2–4% of the world's population hear this. Scientists have been trying to figure out for decades where this sound comes from.

Some people find the sound annoying but can live with it. Others can get sick from this low-frequency sound, which is often also experienced as a vibration.

The humming sound isn't easy to hear outdoors, but it often appears indoors—and is most noticeable when you've gone to sleep at night. If you look out the window to see if there is something with a motor in the neighborhood, there's nothing to see.

And others who are in the same place hear nothing.
The hum phenomenon, a persistent low-frequency sound perceived by 2–4% of people, has unclear origins and is reported globally, often in densely populated or coastal areas. Potential sources include human-made infrastructure, natural phenomena, and individual auditory sensitivity, but most cases are not linked to especially acute low-frequency hearing or measurable oto-acoustic emissions. Evidence suggests that for most individuals, the hum is a form of low-frequency tinnitus, while a minority may detect actual external sounds. Improved understanding of low-frequency auditory processing is needed to clarify the phenomenon’s mechanisms.
The phenomenon was first recorded and discussed in the city of Bristol, England in the mid-1970s. Suddenly, the Bristol Evening Post began receiving letter after letters from people who heard an inexplicable sound, and wondered where it came from.

One theory was that the humming sound came from large, industrial fans that were located inside the warehouse of a large department store. However, when the warehouse was closed down a few years later, people continued to hear the sound.

Since then, the sound has been recorded in several places in the United Kingdom, mainly in coastal cities such as Hythe, Plymouth, Southampton, Swansea, but also in London.

The sound is called the hum phenomenon, or simply the hum.
In the 1990s, it cropped up in the United States, first in the city of Taos, New Mexico and in the city of Kokomo, Indiana. The phenomenon has since been recorded worldwide: in Canada, Australia, New Zealand, South Africa and several European cities. The sound is typically reported in relatively densely populated areas.

A couple of years ago, people in the Oslo area also reported an unexplained humming sound, according to the Norwegian Broadcasting Corporation (NRK).
Part 1

Many different theories have been offered to explain the cause of the phenomenon; everything from acoustic pollution from human-made sources to sounds that nature itself makes—as well as conspiracy theories that the sound is produced by the CIA or even aliens.

There are many human sources of low-frequency sound. These can include ventilation systems, heat pumps, traffic noise, windmills and more. Examples of natural sources include the sounds of waves crashing along the coast and wind sweeping through the landscape.

The hum has attracted the interest of hearing and audiology researchers worldwide.
Other explanations for 'the hum'
Military aircraft and submarines
One theory that has been proposed is that the hum relates to sound waves from US military aircraft that use radio frequencies at the lowest end of the spectrum of sound frequencies to communicate with submarines. These aircraft operate at night, and their movements are top secret. The theory may also explain why many "hum sites" are located on the coast.

Amorous fish
The Scottish Association for Marine Science has suggested that the noise in the UK coastal town of Hythe could be caused by the mating call of schools of male plainfin midshipman fish (Porichthys notatus). Amorous male fish make loud sounds, sometimes for hours, to attract females.

Waves, volcanic eruptions, or lightning strikes
In 2015, French researchers suggested that the hum was caused by waves moving along the seafloor. When the waves collide with ridges on the continental shelves, it creates vibrations that are audible to some.

Other researchers have suggested that vibrations caused by volcanic eruptions and earthquakes could be the cause.

Yet another theory points to the lightning strikes that strike Earth every day. Lightning strikes build up a massive electromagnetic charge that creates a resonance between Earth's surface and the ionosphere—much like blowing air over the top of a bottle.

Sensitive brains
Dr. David Baguley, head of the audiology department at Addenbrooke's Hospital in England, has done extensive research into the phenomenon. He believes it is due to sensitive brains that can pick up ultra-low sound frequencies.

He pointed out that our sense of hearing is greatly affected if we experience a lot of stress, and the brain turns up the volume to detect threatening sounds.

Sounds that can be measured
The researchers tested two hypotheses.

One was that the hum can be measured, both from human-made infrastructure and industry and also from nature itself, which creates low-frequency sounds.

Part 2

These sounds have long wavelengths that can travel over great distances.

The first thing the researchers did was test whether the participants had particularly good hearing for low-frequency sounds that are actually known to exist.

Most did not, except for two participants who had better hearing than average at certain low frequencies.
It still means that the hypothesis of having especially good hearing for low-frequency sounds does not hold for most people.
There are differences in hearing thresholds (microstructures) that make it possible for some people to hear sensitively in a very narrow frequency range, for example between 50 and 51 Hertz. These nuances are not captured by conventional hearing tests.
The ear can produce sounds itself
The cochlea in the inner ear itself produces weak sounds with different frequencies, typically between about 500 and 5000 Hertz. These sounds have no function of their own, but are a by-product of a physiological sound amplification process.

Most of us don't hear these sounds. However, a few people can actually hear the sounds that the ear itself produces. And these sounds can be measured objectively
These particular sounds are called oto-acoustic emissions and can be detected by placing a sensitive microphone in the ear canal. In some people, these spontaneous oto-acoustic emissions can be experienced as troublesome tinnitus.

"One hypothesis was that the participants in our group could hear oto-acoustic emissions at low frequencies.
But… the answer was no.
Sounds that cannot be measured
"Then there are people who hear something that cannot be measured objectively.
Tinnitus or ringing in the ears is when you hear a sound in the ear or in the head, which is not caused by an external sound source.

Many people experience tinnitus, either permanently or for shorter periods. These individuals first experience the sounds in their ears as a sound coming from outside.

But as the sound persists, even when they move to other places, they gradually become aware that the source of the sound is not external.
based on what is known about hearing and the tests they conducted on study participants, the best explanation is twofold.

A few people who hear the hum actually have particularly good low-frequency hearing. However, for most people, it may be a form of tinnitus, meaning a sound that originates from inside the auditory system.
Based on the results, although the researchers haven't ruled out cases of physical external sound sources, they suggest that subjective tinnitus in the low-frequency range is often the cause of hearing pulsations of low-frequency sound perceptions.

Bonifaz Baumann et al, On the potential sources of a low-frequency sound percept that only a few can perceive, PLOS One (2026). DOI: 10.1371/journal.pone.0326818

Part 3

Ebola may have spread beyond Africa. How are health authorities responding?
The current Ebola outbreak, caused by the Bundibugyo strain, has resulted in over 900 suspected cases and 223 deaths in the DRC, with limited spread to Uganda and suspected but unconfirmed cases in Italy and Brazil. International health authorities have declared a public health emergency, implemented travel restrictions, and activated safety protocols. Vaccine development is being accelerated, but the risk of global spread remains low with current containment measures.

Similar to the West African outbreak, this latest Ebola outbreak has spread to other continents through travel.

Nine cases and one death have already been reported in Uganda, which shares a border with the DRC.

An American man who tested positive for Ebola while working in the DRC, is in a stable condition after being treated in Germany.

In Italy, authorities are monitoring a traveler who recently returned from the DRC to the city of Cagliari.

According to some reports, Brazilian authorities are investigating two suspected Ebola cases. They are believed to be two travelers, one who returned from the DRC to São Paulo and the other from Uganda to Rio de Janeiro.

Importantly, both suspected cases have been diagnosed with other illnesses. The São Paulo patient presented with fever and was later diagnosed with severe meningitis. The Rio de Janeiro patient tested positive for malaria after developing a cough, chills and diarrhea, but has since tested negative for Ebola.

So for now, no Ebola cases have been confirmed in Brazil. But these suspected cases have prompted the country to activate its Ebola safety protocols, including patient isolation, laboratory testing, and epidemiological investigations.

Meanwhile, several countries have imposed travel restrictions to prevent Ebola from reaching their shores.

original article.

Older brains work harder to stay upright, with nearly 50% longer delay

Aging is known to degrade sensory systems, posing a major challenge to balance control and resulting in an increased risk of falls.
Researchers  have shed light on the brain mechanisms underlying age-related changes in postural control. Using a novel approach, the researchers discovered that older brains must work significantly harder than younger ones to process sensory information and control movement, alongside a substantial processing delay.

Older adults exhibit significantly increased brain activity and nearly 50% longer processing delays when maintaining balance compared to younger individuals. This heightened neural effort is closely linked to greater postural instability and is not solely explained by vestibular decline, indicating that aging brains require more active control to maintain upright posture.

The study demonstrated that when older adults try to stay balanced, their brain activity syncs up closely with how much they wobble, especially in difficult balancing situations—and those who wobble the most have the highest brain activity.
This means that older adults have to actively maintain their balance, using parts of their brain to stay upright. Younger people, on the other hand, stay balanced automatically without having to think about it or use up mental energy.

Furthermore, it takes significantly longer for an older person's brain to process balance information, almost 50% longer. Interestingly, even though many older participants showed inner-ear decline, this wasn't the reason their brains were working so much harder.

Ultimately, this research helps us understand how the aging brain controls balance, and it opens the door for future studies in medicine and neuroscience to help predict and hopefully prevent fall risks in older adults.

Thomas Legrand et al, Aging increases the cortical resources allocated to static balance maintenance, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2524894123

Short videos may hinder learning by fragmenting attention and memory, study finds

Recent technological advances and the introduction of new digital media platforms have dramatically changed how people learn and source information about topics that interest them. Some recent studies have found that while browsing online or scrolling down social media platforms, users tend to spend under one minute on average on individual videos.

Short videos that summarize concepts have thus become increasingly popular among online content creators. More recently, they have also made their way into some educational settings, yet the extent to which they can support learning and help students memorize information remains unclear.

Researchers recently set out to assess the potential of short videos and longer videos as learning resources. Their findings, published in Communications Psychology, suggest that short videos are significantly less effective learning tools than longer videos, as people tend to rapidly forget the information presented in them.

The rapid rise of short videos, particularly social media-style formats characterized by rapid switching and fragmented content, has led to their increasing integration into learning environments, wrote the researchers in their paper, but  their efficacy and neurocognitive impact remain contentious.

The researchers carried out three separate experiments involving over 150 college students. 

The videos that participants watched were either 10 minutes long or spanned between 30 seconds and two and a half minutes. In addition, some participants were explicitly asked to memorize the content of the video, while others were not.

"Across three experiments, memory performance and forgetting rate were assessed under both incidental and intentional encoding conditions, and inter-subject correlation (ISC) analysis was employed to investigate neural response patterns during short video viewing," wrote the authors. "Behaviourally, participants learning with short videos showed significantly lower immediate memory accuracy across encoding conditions and exhibited a higher rate of forgetting when explicitly instructed to remember."

Notably, the study participants watched videos inside a functional magnetic resonance imaging (fMRI) scanner, a machine that maps activity in the brain by tracking changes in blood flow. The research team later analyzed the fMRI scans they collected and tried to uncover neural activity patterns associated with viewing short and long videos.

"At the neural level, ISC analyses revealed that short videos elicited reduced neural synchrony in key brain regions supporting visuospatial attention, episodic memory, and cognitive control, including the superior parietal lobule, precuneus, and middle occipital gyrus," wrote the researchers. "In contrast, short videos evoked higher synchrony in temporal and frontal regions associated with bottom-up attentional processing. Furthermore, functional connectivity analyses indicated that SVs weakened coupling between visual, attentional, and cognitive control networks."

Part 1

The results of the team's experiments suggest that when people watch short videos, they do not remember the information presented to them as well as they would when watching longer videos. In addition, the researchers found that while their study participants were watching short videos, brain regions involved in attention, episodic memory (i.e., memory of events or facts) and cognitive control (i.e., the control of mental functions) were less synchronized.

In contrast, they recorded a greater synchrony between brain regions linked to a focus on external stimuli. Collectively, these observations suggest that the disjointed and rapidly changing quality of short videos interferes with the deep processing of information, making it harder for viewers to memorize contained information or acquire new knowledge.
Together, these findings suggest that the fragmented and rapidly switching nature of typical social media short videos enhances bottom-up attentional capture at the expense of top-down cognitive processes critical for deep learning and long-term memory consolidation," wrote the authors. "This study provides converging neurobehavioral evidence suggesting that SVs viewing in social media contexts is associated with reduced neural synchronization and poorer memory performance."

Meiting Wei et al, Learning via short videos impairs memory accuracy and reduces brain synchrony, Communications Psychology (2026). DOI: 10.1038/s44271-026-00476-x

Part 2

Charred Bronze Age teeth unlock age at death despite cremation

Over 3,000 years ago, the people of Bronze Age Poland burned their dead and placed their ashes in urns, often destroying the intimate records of their lives preserved in their bones. Now, researchers have shown that some of these records can still be read, hidden in the charred roots of their teeth.
The new study, published in Scientific Reports, has shown that microscopic growth lines in teeth may offer a promising alternative to traditional methods, which are often too scrambled or destroyed to provide an age-at-death. Additionally, the researchers made a surprise discovery, finding that growth lines may also provide insights into a person's diet, environment, or some other part of daily life.

"Cremated human remains are often considered extremely difficult to study because fire changes the structure of bones and teeth so dramatically. Scientists now accepted this challenge.
As the tooth root grows, it leaves behind alternating dark and light lines that researchers can use to estimate age at death.
To test whether these lines persisted in ancient cremated remains, the team examined 62 tooth roots from across Poland's Lusatian Urnfield culture, which existed during the Late Bronze and Early Iron Age, roughly 3,300 to 2,500 years ago.

The name 'Urnfield' comes from the widespread practice of cremating the dead and burying their ashes in ceramic urns gathered in large cemeteries, sometimes containing hundreds or even thousands of graves.
For the Lusatian Urnfield culture, cremation was not just common, it was near universal. This makes intact bodies extremely rare, forcing researchers to rely on the broken and burned cremated bones, which often leave unanswered questions.
The researchers sliced the teeth into paper-thin sections for microscopic examination. They then had two researchers count the lines and compare them to surviving alternative age estimates. Not only did the tooth-based estimates align with traditional methods, but they also pinpointed the age to a much narrower timeframe.

Intriguingly, the researchers also noticed the line thickness varied. While previous researchers had suggested this may be the result of differences between males and females, the study authors found the width was likely related to geographic region.

It is possible these differences are related to different environments, diets, or other aspects of daily life that may have affected the teeth. However, the researchers are careful to note that the findings are preliminary.

Agata Hałuszko et al, Methodological validation and inter-site analysis in Late Bronze and Early Iron Age cremations using tooth cementum annulation counts, Scientific Reports (2026). DOI: 10.1038/s41598-026-51841-z

Even years after stroke, spinal cord stimulation could improve arm function

Researchers report the final outcomes of a pioneering pilot clinical trial using electrical stimulation of the spinal cord to improve arm and hand mobility in people with chronic stroke in Nature Medicine.
The study, which was primarily focused on investigating safety and preliminary efficacy, showed that seven participants with profound muscle weakness due to stroke experienced an average 32% increase in arm strength, along with improvement in overall arm mobility and reduction in muscle spasticity.

Importantly, the intervention required fewer than nine hours of movement-based training over four weeks and did not cause discomfort or serious adverse events.

The stimulation works mostly as an assistive technology—when it's on, people can move better. By stimulating the spinal cord, we can immediately allow residual connections between the brain and the spinal cord to work more efficiently, enabling better movement.
Stimulation sends targeted electrical signals to sensory nerve fibers in the spinal cord to enhance communication between the brain and weakened muscles. The same class of device has been used for decades to treat chronic pain, but this is the first time it has been used to restore arm function after stroke.
Researchers observed two distinct types of benefit. Over the four-week study period, all seven research participants experienced immediate improvements in strength when stimulation was turned on, regardless of how severe their impairment was at baseline. Additionally, spasticity—abnormal muscle stiffness caused by stroke-damaged nerve pathways—was reduced in all seven participants.
This approach is designed to rapidly help people move their arms better, even years after a stroke.

Spinal cord stimulation for upper limb motor function in people with chronic post-stroke hemiparesis: a feasibility trial, Nature Medicine (2026). DOI: 10.1038/s41591-026-04435-1

UN report warns AI could soon use 3% of world's electricity and more water than we need to drink

By 2030, AI could consume 3% of global electricity, emit carbon equivalent to the UK, and use more water for cooling than the annual global drinking water requirement. Efficiency improvements may not reduce total resource use due to increased demand, following the Jevons paradox. The report emphasizes the need for responsible AI governance, environmental disclosures, and integration of sustainability into AI development and policy.

original article.

Moms' learned fear of snakes gets inherited by offspring in a critically endangered mouse, biologists discover

Conservationists often raise the young of endangered species in captivity before releasing them into suitable habitats as adults. The benefits are obvious: survival to adulthood is typically high, as captive animals are safe from predators and food scarcity. Unfortunately, a lack of exposure to enemies in early life may become a drawback later, if the released individuals have never learned to recognize and avoid their predators.
One way to fix this is "antipredator training," where young animals are confronted with fake or real predators and taught to associate these with an unpleasant stimulus. However, this method is labor-intensive and depends on the realism of the training and the ability and most sensitive period for learning of the captive species. But now, researchers may have found a more efficient alternative: train the mothers instead.

Predator training of pregnant Pacific pocket mouse females resulted in their female offspring exhibiting increased vigilance toward snakes, while no such effect was observed in male offspring. No significant improvement in post-release survival was detected, possibly due to limited sample size and pre-release exposure. Maternal effects may be mediated by prenatal programming, postnatal behaviour, or odour cues.

Female offspring of predator-trained mothers were more vigilant during predator encounters, suggesting that maternal experiences may shape offspring behavior in ways that could be useful for conservation breeding and reintroduction programs.
Researchers conducted a randomized controlled experiment with two arms on 22 pregnant females in the second half of gestation. Each trial was filmed and lasted 20 minutes. Half of the females were assigned to the predator-exposed treatment, in which they were placed in a testing arena with food.

After acclimatization, a live kingsnake (a native predator of small mammals) was introduced behind a wire mesh across the arena. Pocket mice were sprayed with water whenever they approached the snake.

The mice received scores for behavior, location, and orientation relative to the snake. The remaining pregnant females were assigned to the control, where the snake was replaced with a rope of similar length. Control females were never sprayed.

Once pups had been born (87 in total) and reached 30 days of age, the scientists tested their behaviour towards a snake following the same protocol. A subset of 44 offspring were then released into suitable habitat within coastal southern California, while their post-release survival was assessed through live trapping towards the end of the summer active season.
The results showed that in the snake's presence, daughters of predator-trained mothers displayed more vigilance behaviours like scanning, freezing, and rearing up to monitor their surroundings and assess potential threats. However, no such difference was found between sons of predator-trained mothers and sons of control mothers.
Part 1

The authors concluded that giving anti-snake training to pregnant females makes their daughters, but apparently not their sons, more cautious around snakes.

Does this mean that at least females whose mothers had been trained survive better in the wild? The authors did not find any boost on survival after release. But they caution against concluding too quickly that no beneficial effects exist, given the small sample size and that all mice underwent exposure to snakes before release.

And how might the learned caution towards snakes have been transmitted from trained mothers to their female offspring?

"One possibility is prenatal programming, where stress hormones associated with predator training during pregnancy influenced offspring development before birth. Another is that the mothers behaved differently after the pups were born, which could likewise shape the latter's behaviour. It is also possible that pups detected lingering odour cues from the antipredator training in their mother.
Researchers don't yet know why female offspring responded differently than males, but sex-specific responses to stress and predator cues have been observed in other species. Maternal predator training may have amplified those innate differences.

Sex-specific Effects of Maternal Predator Exposure on Offspring Antipredator Behavior in an Endangered Mammal, Frontiers in Ecology and Evolution (2026). DOI: 10.3389/fcosc.2026.1783876

Part 2

How culture, stress, and social life may shape gut health
Gut health is shaped by complex interactions among biological, psychological, and sociocultural factors, including stress, social relationships, economic status, and cultural norms. Chronic stress and adverse social conditions can disrupt the gut–brain axis, alter gut microbiota, and intensify gastrointestinal symptoms. Holistic, personalized approaches that address both biological and psychosocial aspects are increasingly emphasized for effective management.

Reuben K. Wong et al, Sociocultural Aspects of the Pathophysiology, Clinical Presentation, and Management of Disorders of Gut–Brain Interaction, Gastroenterology (2026). DOI: 10.1053/j.gastro.2026.02.006

Early diet may shape how the teenage brain develops
Early-life diet, particularly during infancy, is linked to cognitive outcomes in adolescence, with poorer early nutrition associated with lower intelligence later on. Evidence for the impact of adolescent diet on brain development is mixed, highlighting the need for better-designed studies. The timing of dietary exposure, population characteristics, and intervention specifics influence observed effects.

Hayley A Young et al, Diet and the Developing Brain: A Systematic Review of Nutritional Influences on Adolescent Cognitive and Academic Outcomes, Advances in Nutrition (2026). DOI: 10.1016/j.advnut.2026.100648

Physicists Just Achieved 'Perfect Randomness' For The First Time Ever

One of the hardest things to do in physics is to generate true, provably unpredictable randomness. That's because it's impossible to determine randomness based on the output alone. Dice may have nicks and flaws that influence how they roll. Computer random-number generators are usually driven by algorithms. Even coin flips are governed by physical forces that, in theory, could be predicted. The difficulty lies not in generating numbers that appear random, but in showing that no one could have possibly predicted the outcome – that the system isn't secretly affected by subtle hidden rules or biases. Now, a team of physicists at ETH Zurich in Switzerland has overcome that challenge by leveraging one of the strangest phenomena in quantum mechanics: entanglement. The resulting sequence of zeros and ones is now really perfectly random, and they can even certify that!

https://www.nature.com/articles/s41586-026-10521-8

Vitamin A poisonings rose almost 40% as measles misinformation spread in 2025

There can be too much of a good thing, and that has been the case with Vitamin A.
A recent study in JAMA Network Open has found that between January and March 2025, America's Poison Centers reported a 38.7% increase in vitamin A exposures during the measles outbreak across many states.
While it is not unusual for people to reach for acetaminophen (Tylenol) or ibuprofen to relieve fever or pain, the sudden interest in vitamin A in response to the measles outbreak was neither expected nor evidence-based, as it does not prevent measles. So what led to this uptick in search?

The researchers found that the surges coincided with two key events: the first of several media statements promoting vitamin A as a measles treatment on February 19, 2025, and comments by Dr. Suzanne Humphries on the hugely popular The Joe Rogan Experience podcast, where she promoted vitamin A and cod liver oil as treatments for measles. Misinformation, especially in a world that is chronically online, often spreads like wildfire.
Measles, also known as rubeola, is a viral disease that causes a high fever, cough, runny nose, red eyes, and a widespread rash. It spreads through the air when an infected person coughs or sneezes, and the virus can remain airborne for up to two hours after they leave the room. Measles can also cause serious complications, including pneumonia, brain swelling, and even death, particularly among young children and people with weakened immune systems.

Measles was once a common childhood illness, but thanks to vaccination, an estimated 59 million deaths from measles between 2000 and 2024 were prevented. The U.S. successfully eradicated the disease in 2000, and the 2025 measles outbreak has been the largest since then. The reluctance to vaccinate children against the disease is a major reason for the resurgence.
Along with hesitancy, interest also grew in alternative methods to prevent the disease, such as vitamin A and cod liver oil. Vitamin A is essential for good vision, skin, hair, and immunity, and can support recovery from measles when used under medical supervision. However, it does not prevent infection, and—when taken in excessive amounts—can lead to nausea, headaches, dizziness, and liver damage.
Part 1

Previous studies have established how social media and online trends can have an impact on public health concerns and behaviors. So, the researchers investigated what people were searching for on the internet and compared what was being said in the media. They input keywords such as "vitamin A measles" and "cod liver measles" in Google Search Trends to see how often people in the U.S. searched for the terms between January and June 2025. Alongside this, they closely monitored press coverage, online mentions and social media statements on the topics.

The researchers found that interest in vitamin A and cod liver oil surged after public figures and government officials began promoting vitamin A. Searches for vitamin A rose 7.5 percentage points above expected levels, while searches for cod liver oil increased by 1.3 points. At the same time, poison centers reported a significant rise in exposure to dangerous amounts of vitamin A, most of them involving children.

The findings provide a clear example of how quickly media messaging might shape health-seeking behavior during public health crises such as measles outbreaks. Misinformation about health can have lasting impacts on a person's life, which calls for prompt attention and debunking by public health officials.

Anne Christine Bischops et al, Internet Searches for Vitamin A and Related Media Statements During the 2025 US Measles Outbreak, JAMA Network Open (2026). DOI: 10.1001/jamanetworkopen.2026.15013

Part 2

AI fails classic attention test, with longer word lists triggering dramatic accuracy collapse
Transformer-based large language models exhibit a dramatic decline in accuracy on the Stroop task as word list length increases, particularly when word meaning and ink colour are mismatched. Unlike humans, who maintain high accuracy regardless of list length, LLMs default to word reading and fail to sustain task focus, indicating fundamental limitations in their attention mechanisms compared to biological systems.

Suketu Chandrakant Patel et al, Deficient executive control in transformer attention, PNAS Nexus (2026). DOI: 10.1093/pnasnexus/pgag149

Worm tablet could be repurposed as brain cancer treatment
Mebendazole, an antiparasitic drug, demonstrated consistent tumor growth inhibition and increased survival in laboratory and animal models of brain cancer, acting through multiple anticancer mechanisms and enhancing effects of chemotherapy and radiotherapy. However, human studies show limited and inconsistent efficacy, indicating that mebendazole remains an unproven candidate requiring further clinical trials before routine use in brain cancer treatment.

Ciara B. Blum et al, From anthelmintic to neuro‐oncology: A systematic review of mebendazole repurposing for brain tumour therapy, British Journal of Clinical Pharmacology (2026). DOI: 10.1002/bcp.70565

Why doesn't coffee taste like caffeine?

Through a series of tests aided by a trained panel, researchers discovered that caffeine must be interacting with other molecules present in coffee that significantly reduce its bitterness. In fact, coffee masked caffeine's distinctive taste until researchers added 10 times the normal amount of caffeine present in a typical brew.
Caffeine is highly bitter in isolation, but its bitterness is significantly reduced in coffee due to interactions with melanoidins and chlorogenic acid formed during roasting. These compounds, especially melanoidins, likely bind caffeine, preventing it from activating bitter taste receptors and resulting in coffee's characteristic, less bitter flavour profile.
To find the coffee molecules responsible for this effect, the team ran taste-tests of caffeine in solution combined with additional compounds: chlorogenic acid, which is naturally present in coffee beans, and/or melanoidins, which are products of the Maillard reaction that occurs during roasting.

The tasting panel found that when both compounds were combined with caffeine, the bitter taste was reduced by about half. Frank suspects that caffeine and melanoidins form a complex that—due to its size—prevents interaction with the bitter taste receptors on our tongues. The strength of the bond between caffeine and melanoidins may differ between different roasting processes, though future work is needed on this point.

A plethora of bitter stimuli, generated during the roasting process, culminate in the unique, bitter taste of coffee beverages.

Michael Gigl et al, Impact of Interactions between Melanoidins and Caffeine on the Bitter Taste of Coffee Beverages, Journal of Agricultural and Food Chemistry (2026). DOI: 10.1021/acs.jafc.5c17022

Biomaterial made from jackfruit latex is a promising treatment for periodontitis

A biomaterial composed of jackfruit latex, pomegranate peel extract, and simvastatin forms a mucoadhesive matrix that enhances osteoinduction in vitro, indicating potential for periodontal tissue regeneration. The formulation supports localized drug delivery, increases bone formation, and may reduce systemic side effects compared to oral simvastatin.

Bruna V. Quevedo et al, Jackfruit latex-pomegranate extract biomaterial incorporated with simvastatin as a potential osteoinductive system for periodontal applications, Polymer Bulletin (2026). DOI: 10.1007/s00289-026-06358-w

Cells have a built-in 'seatbelt' against sudden stress

When cells experience sudden physical stress, like stretching or pressure, they can activate a fast, protective mechanism that shields their nuclei from destruction, according to a new study published in the Biophysical Journal. This mechanism could help scientists develop therapies to prevent DNA damage, a major driver of aging and cell death.

Epithelial cells rapidly form an actin-based ring around their nuclei in response to acute mechanical or osmotic stress, providing immediate physical protection and reducing nuclear rupture and DNA damage. This transient structure increases lamin A/C expression, stiffening the nuclear membrane. Impaired actin ring formation leads to increased DNA damage and cell death, suggesting a potential link to aging.

Aging cells tend to have lower levels of actin in them, which means they may not produce the ring structure as effectively as healthy cells.

Transient Perinuclear Actin Rings Prevent Cell Aging And Apoptosis Via Nuclear Mechanical Protection, Biophysical Journal (2026). DOI: 10.1016/j.bpj.2026.04.035

The perks of polyandry: Mating with multiple males leads to home improvement for African tree frogs

The question of why females mate with multiple males has long puzzled evolutionary biologists. A new study of African foam-nest tree frogs, led by University of Wollongong (UOW) researchers, reveals polyandry could be the key to reproductive success and a safer home for offspring. The findings shed light on how amphibians have evolved to protect their young in challenging environments, presenting a new hypothesis for the evolution of polyandry that ties mating behavior to the quality of nest construction.
Polyandry in African foam-nest tree frogs results in larger, more robust nests that are less likely to fail, enhancing offspring survival. Multiple males assist in nest construction and gain partial paternity, indicating cooperative rather than competitive reproductive behaviour. These findings suggest that nest-building requirements may drive the evolution of polyandry in various animal species.

Phillip G Byrne et al, "Nesting assistance": a new hypothesis for the evolution of polyandry and a test in an African foam-nesting treefrog, Evolution (2026). DOI: 10.1093/evolut/qpag071

Dogs respond to human tone without words, hinting at communication older than language

Humans can communicate various instructions to dogs without using actual words—simply by modulating the tone of their voice, a new study shows. By repeating the nonsense syllable 'bü' in different intonations, humans successfully signaled "Yes," "No," "Here," and "There" and, remarkably, dogs responded correctly, despite receiving no prior training. The findings reveal ancient acoustic codes, interpretable across species, that predate language itself.

Dogs accurately interpret human intentions such as affirmation, prohibition, and spatial direction based solely on vocal tone, even without word use or prior training. Specific acoustic features—such as pitch, smoothness, and call duration—encode these meanings, indicating the presence of ancient, cross-species vocal communication codes that predate language.

Anna Gábor et al, Cross-species acoustic codes for yes and no in human nonverbal vocalizations, Cognition (2026). DOI: 10.1016/j.cognition.2025.106284

"Yes" and "no" are among the most commonly used words. But the origins of these simple meanings are older than language, and even older than humans.

Why do male chimpanzees throw rocks at the same trees for more than a decade?
Male chimpanzees throw rocks at specific trees over long periods as part of a rare, culturally transmitted behavior, likely linked to communicative or symbolic functions within their social groups. This accumulative stone throwing is not related to food acquisition and is observed only in select West African populations, suggesting cultural specificity. The behavior may mark important locations and is maintained for over a decade, but its precise meaning remains unclear.

original article.

Aspirin may unmask silent bladder cancer by triggering bleeding
Initiation of aspirin therapy is associated with increased cystoscopy rates and detection of bladder cancer at less invasive stages, likely due to aspirin-induced urinary bleeding unmasking asymptomatic tumours. In contrast, NSAID initiators showed increased cystoscopy rates without a corresponding increase in bladder cancer detection or shift in stage distribution.

Malene Söth Hansen et al, Aspirin or non‐steroidal anti‐inflammatory drug initiation and subsequent bladder cancer evaluation, Journal of Internal Medicine (2026). DOI: 10.1111/joim.70115

Celiac disease tied to higher risk for solid organ transplants

Celiac disease (CeD) is associated with a nearly tripled risk for needing a solid organ transplantation, according to a study published online May 28 in Clinical Gastroenterology and Hepatology.
Celiac disease is associated with a nearly threefold increased risk of solid organ transplantation compared to the general population, with particularly elevated risks for liver (aHR 7.26) and kidney (aHR 1.85) transplants. No significant difference was observed for heart transplantation risk.

John B. Doyle et al, Risk of solid organ transplantation in individuals with celiac disease: a nationwide cohort study, Clinical Gastroenterology and Hepatology (2026). DOI: 10.1016/j.cgh.2026.04.034

Air pollution may be harming your brain's 'encyclopedia'

A new study by researchers found that higher exposure to very small air pollution particles (PM2.5) over a 17-year span was associated with lower semantic memory. Semantic memory acts like the brain's "encyclopedia" for things like facts, words and long-term general knowledge.
Semantic memory is essential for communication, comprehension and navigating everyday life.
Long-term exposure to higher levels of fine particulate air pollution (PM2.5) is associated with lower semantic memory performance in older adults, independent of age, education, income, and marital status. The impact of PM2.5 on semantic memory exceeds that expected from a decade of normal aging, while executive function and verbal episodic memory were not affected.
Two other measures of cognitive function—executive function and verbal episodic memory—did not show an impact related to the pollution.

The researchers found:

People who were exposed to higher levels of PM2.5 pollution over many years scored noticeably lower on semantic memory tests than those exposed to lower levels of pollution.
The association with PM2.5 pollution persisted even after accounting for other factors such as age, education, income and marital status.
The effect of long-term PM2.5 exposure on semantic memory was greater than what researchers would expect from 10 years of normal aging.

How individuals can reduce exposure to air pollution
While air pollution is largely a community-level issue, there are many ways individuals can reduce their exposure to air pollution:

Check daily air quality forecasts on AirNow. The EPA website lets you enter your ZIP code to find out about air quality, which accounts for fine particulates, in your area.
Limit outdoor activity when pollution levels are high, especially during wildfire smoke events.
Use high-efficiency (HEPA) air filters indoors.
Keep windows closed on poor air quality days.
Avoid exercising near busy roads or heavily trafficked areas.
Use recirculated air settings in vehicles during heavy traffic or smoky situations.

Stacey E. Alexeeff et al, Particulate air pollution and domain‐specific cognition among Black adults, Alzheimer's & Dementia: Behavior & Socioeconomics of Aging (2026). DOI: 10.1002/bsa3.70074

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Science Media Amplifies Male Scientists’ Voices Over Female Ones

Analysis of more than 2,500 science stories revealed that men were quoted more often than women, highlighting systemic gender bias in science communication.
According to the Global Media Monitoring Project (GMMP), which analyzes gender in news, only 26 percent of the people seen, heard, or spoken about in the news are women. Merryn McKinnon, a science communication researcher at the Australian National University, set out to investigate whether science news reflects a similar imbalance.

By analyzing STEM stories in Australian media over five years, McKinnon and her colleagues found that men were more frequently used as direct sources, even in disciplines dominated by women.1 Their findings, published in the Journal of Science Communication, reveal that stories shaping public understanding of science continue to cater to male voices and expertise, underscoring the importance of journalists, organizations, and science communicators in increasing the diversity of their sources.
Female Voices Are Consistently Underrepresented in Science News

McKinnon M, et al. Gender in Australian science news. J Sci Comm. 2026;25(3).

Confronting risks of mirror life

‘Mirror life’ study reignites fierce debate

Mirror life — a hypothetical form of microbes that use mirror-image versions of the biological molecules that exist in nature — might not pose an existential threat to life after all, says a team of researchers. In a modelling study, the group found that mirror organisms would struggle to survive in the wild because they would require ‘mirror’ nutrients that don’t exist naturally. The study has prompted criticism from other researchers — including some who co-authored a 2024 paper calling for all work to create mirror life to be halted — who counter that mirror life would quickly adapt to new conditions.

https://www.biorxiv.org/content/10.64898/2026.05.07.723461v2

https://www.science.org/doi/10.1126/science.ads9158

CAR-T enables kidney transplants

A single dose of engineered immune cells has helped three people with ‘highly sensitized’ immune systems to receive life-saving kidney transplants. People in this group are often ineligible for transplants because their bodies usually reject the donated organ. Researchers engineered the recipient’s own immune cells into chimeric antigen receptor (CAR) T cells that ultimately reduce the trouble-making antibodies that push their immune systems into overdrive. More than a year after receiving the cells, the three people are now living with new kidneys and without notable side effects.

https://www.nejm.org/doi/10.1056/NEJMoa2513428

https://www.nejm.org/doi/10.1056/NEJMc2517277

Bacteria can learn and form memories without a brain

Researchers have shown that bacteria can learn from past experiences, store memories across generations and adapt their behaviour to changing environments, all without a brain or nervous system. The research could shape how scientists think about bacterial infections and antibiotic treatment.
E. coli bacteria can encode and transmit memories of past environmental conditions, enabling adaptive responses to fluctuating nutrient availability. These memory effects persist across generations via inherited molecular components, influencing behaviour even in descendants. The findings indicate bacterial responses depend on both current and historical environments, with implications for understanding infection dynamics and antibiotic resistance.
In a study published in PRX Life, researchers tracked individual E. coli cells as nutrient conditions shifted between rich and poor environments. Instead of responding the same way every time, the bacteria adjusted their growth based on patterns they had experienced before. Cells exposed to rapidly changing conditions were able to adapt better than cells raised in more stable environments.

The findings suggest bacteria do more than just react to their surroundings. They appear to encode memories of past environments and use those memories to guide future behaviour.

Josiah C. Kratz et al, Multi-Timescale Adaptation and Emergent Learning in Single Bacterial Cells, PRX Life (2026). DOI: 10.1103/5zbg-8vll

Corals have a hormonal clock and it looks surprisingly like ours

A three-year study has cracked open the hidden biology behind coral reproduction, revealing hormone cycles that echo those of humans and other animals, and a new way to detect reef distress before it's too late.
Corals exhibit annual reproductive hormone cycles, with estrogen peaking months before spawning and progesterone surging after, paralleling patterns seen in other animals. Sunlight, rather than temperature, primarily regulates these hormone levels. These findings provide a baseline for detecting reproductive stress in corals, aiding early intervention in reef conservation.

Once a year, on cue, corals across a reef release their eggs and sperm into the sea simultaneously. Coral reproduction is one of nature's most spectacular events. For reefs increasingly threatened by warming, pollution and overfishing, getting that timing right is a matter of survival.
A team of researchers has uncovered evidence that corals may rely on hormone cycles like those used by many animals, including humans, to prepare for reproduction.
Their findings reveal a hidden biological rhythm that may help explain how corals coordinate reproduction and how scientists might detect reproductive stress before spawning failures become visible.
Scientists had previously suspected that estrogen-like hormones would peak just before corals spawned. Instead, the researchers found that estrogen levels reached their highest point months earlier, during the earliest stages of egg development, before steadily declining as eggs matured.

Meanwhile, progesterone remained relatively stable throughout the reproductive season but surged several months after spawning, suggesting it may help initiate the next reproductive cycle.

Equally surprising: Sunlight, not heat, emerged as the dominant driver of these hormone levels.
So there's a whole process beforehand, driven by these familiar reproductive hormones, which are remarkable to find in corals, animals so evolutionarily distant from us.
The team discovered another surprise inside individual coral colonies. Hormone levels were distributed fairly evenly throughout the colony, yet the central portions of corals were far more likely to contain developing eggs than the growing outer edges. The finding suggests that local conditions within a colony, such as age, energy reserves or developmental stage, may determine which polyps respond to reproductive signals.

Beyond advancing basic science, the findings could have practical implications for conservation.

Chen Azulay et al, Steroid hormones dynamics during coral reproduction: Multi-year patterns in Acropora eurystoma from the Red Sea, iScience (2026). DOI: 10.1016/j.isci.2026.116205

Scientists map more than 200 years of nature's progress
Comparisons of current mammal communities along the Lewis and Clark Trail with historical records reveal significant changes in species composition and ecosystem function, largely due to land use, development, and species loss over two centuries. Dominant species such as bison and wolves are now absent or greatly reduced, indicating altered ecological roles and community dynamics.

For scientists, the project's goal goes beyond documenting which species remain. By pairing modern data with Lewis and Clark's observations, they are examining how centuries of land use, development, and species loss have reshaped entire ecosystems.

https://showme.missouri.edu/2026/mizzou-helps-smithsonian-map-more-...

Why does the Y chromosome retain UTY?

The human Y chromosome has lost many of its ancestral genes over millions of years of evolution. Yet a small number of genes, including UTY, have been evolutionarily retained despite their weak expression and reduced enzymatic activity. Why these genes persist has remained a longstanding question in chromosome biology.

A study, published in the journal Development, is the first to precisely map endogenous UTY occupancy across the human genome and demonstrate that UTY remains functionally involved in transcriptional regulation during early human development.
UTY is retained on the Y chromosome because it continues to contribute to transcriptional regulation during early human development, co-occupying active cis-regulatory elements with its X homolog UTX and supporting pluripotency-associated transcription factor localization. Despite weaker expression and occupancy than UTX, UTY maintains residual, largely noncatalytic regulatory functions, suggesting it is in an evolutionary transition phase rather than being fully redundant or lost.

Tomohiko Akiyama et al, Functional redundancy between UTY and UTX in regulating the localization of transcription factors involved in pluripotency, Development (2026). DOI: 10.1242/dev.205328

How often do people pass gas?

Flatulence, or farting, is something people often joke about or find embarrassing when it happens unexpectedly. It is, however, an essential bodily function that allows the digestive system to keep pressure within the intestinal tract low and prevents painful stretching of the stomach and intestines. Even though it is normal to fart, it remains unclear what counts as a healthy number.

A study by researchers from the Commonwealth Scientific and Industrial Research Organisation wanted to measure how many times people pass gas in a day. So they designed a mobile phone application, Chart Your Fart, that allowed more than 6,400 Australians to log their farting patterns in real time.

They found that most people, on average, passed gas five times a day, with men doing it more often than women. Flatulence patterns were not the same throughout the day.

They observed a gradual increase that typically peaked between 6 p.m. and 10 p.m., coinciding with the time when people generally consume the most calories and fiber.

When we fart, our body releases a mixture of gases accumulated from two very different origins. The first is the air that sneaks in when you are eating or drinking, and the second is the gases churned out by the billions of bacteria living in the gut during digestion.

The swallowed air is harmless and odorless, but the byproduct of the bacterial breakdown of food contains sulfurous compounds that are responsible for the notorious smell associated with flatulence.

Some food groups, such as fiber, can often lead to more frequent passing of gas, and so can gastrointestinal problems such as irritable bowel syndrome, or IBS. While too much can be an issue, too little is actually the bigger concern. A sudden inability to pass gas, especially alongside stomach pain or bloating, can signal a blockage or other serious gut problem that needs medical attention.

Researchers have not yet been able to clearly define what counts as excessive, too little or normal passing of gas. Without solid data on how often healthy people actually pass gas in daily life, it is difficult to know what is healthy and what is a potential digestive problem. Past studies usually looked at small groups of people or focused only on those with stomach problems.

In the study nearly 80% of participants fell within a range of two to seven times daily. The youngest group, ages 14 to 25, reported passing gas less often than all other age groups, while men averaged 5.2 times per day compared with 4.8 times for women. The number of recordings remained low during midday and began to rise after 6 p.m., when people are more likely to start eating their highest-calorie meals.

The researchers highlight that this study might be one of the first to describe real-time flatulence habits in a large, general population. Establishing what is normal for flatulence can not only provide a helpful starting point for discussions about symptoms at both ends of the spectrum, but also help monitor gut health and change social attitudes toward flatulence.

Emily Brindal et al, Regular Flatulence Patterns Among Community-Dwelling Individuals in Australia, JAMA Network Open (2026). DOI: 10.1001/jamanetworkopen.2026.15637

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How mechanical stress can accelerate bone destruction in periodontitis
Mechanical stress from excessive bite force alone does not cause alveolar bone loss but significantly accelerates bone destruction when combined with periodontitis. Gene expression analysis in mouse models showed that key inflammatory and bone metabolism pathways are upregulated only when both conditions coexist, indicating that mechanical overload amplifies periodontitis-induced bone loss through enhanced inflammatory signalling.

Part 1

Excessive bite force does not cause alveolar bone loss but significantly worsens it when combined with periodontitis, report researchers in a new study. While traumatic occlusion has long been suspected to exacerbate periodontitis, the molecular mechanisms behind this link were poorly understood. Now, using mouse models of both conditions separately and combined, the researchers conducted comprehensive gene expression analysis across multiple periodontal tissues, identifying key inflammatory pathways upregulated in bone when both conditions were present.
Periodontitis, or inflammation of the tooth-supporting tissues, is one of the most common chronic diseases worldwide and a leading cause of tooth loss in adults. It develops when bacterial buildup around the teeth triggers persistent inflammation, gradually destroying their supporting bone and tissue structures. While bacterial infection is the primary driver of periodontitis, other factors also influence how severely and quickly the condition progresses. These include lifestyle habits such as alcohol consumption and smoking, autoimmune disorders, and—as researchers have long suspected—the way teeth come together when biting or grinding.

When teeth are repeatedly subjected to abnormal or excessive bite forces, known as "traumatic occlusion," supporting structures come under intense mechanical stress. For decades, dentists and scientists have hypothesized that this overload can worsen periodontitis excessively, so that occlusal adjustment (reshaping of the biting surfaces) is already used in clinical practice as a part of gum disease treatment.
Using advanced imaging techniques, including micro-computed tomography, the team measured bone loss around the teeth. They also performed transcriptome analysis to examine the activity of thousands of genes in gum tissue, bone, and the periodontal ligament shortly after disease induction. This enabled them to capture early changes in gene expression associated with each condition. Additionally, they investigated the effects of long-term traumatic occlusion alone over a period of eight weeks.

Interestingly, mice exposed only to traumatic occlusion did not show significant bone loss, even after prolonged exposure. However, when traumatic occlusion was combined with periodontitis, bone loss became significantly more severe.
This confirms that excessive bite force does not directly cause damage but instead amplifies the destructive effects of existing dysregulation caused by periodontitis.

Yosuke Tsuchiya et al, Traumatic Occlusion Exacerbates Bone Resorption by Modifying Gene Expression in the Bone Tissue of Ligature‐Induced Periodontitis in Mice, Journal of Clinical Periodontology (2026). DOI: 10.1111/jcpe.70112

Part 2

Hay fever, antihistamines and the evidence on dementia risk

For millions of people around the world, pollen season means weeks of sneezing, itchy eyes, and a blocked or runny nose. The timing varies depending on where you live and which plants are in flower, but grass pollen is one of the most common triggers.
Hay fever, also known as seasonal allergic rhinitis, is an allergic reaction to airborne pollen. Many people manage their symptoms with antihistamines bought from a pharmacy. But recent headlines have raised a worrying question: could some of the medicines used to relieve hay fever symptoms increase the risk of dementia?

Antihistamines block histamine, a chemical released by the immune system during an allergic reaction. Histamine causes symptoms such as itching, sneezing, and a runny nose.

Older, first-generation antihistamines, such as diphenhydramine and chlorphenamine, are more likely to cause drowsiness. Newer, second-generation antihistamines, such as cetirizine, loratadine, and fexofenadine, are generally less sedating.

Some older antihistamines also reduce the activity of acetylcholine, a chemical messenger involved in attention, learning, and memory. Medicines that block the action of acetylcholine are described as having anticholinergic effects.
These older medicines should be used cautiously, particularly in later life. They can cause drowsiness and concentration problems, increasing the risk of falls. People should also take care when driving if a hay-fever medicine makes them sleepy, as highlighted in recent reports.
Some studies have found an association between prolonged use of medicines with strong anticholinergic effects and a higher risk of dementia. These include some treatments for depression, Parkinson's disease, and bladder problems, as well as certain older antihistamines.

There is a plausible reason for concern: acetylcholine plays an important role in memory and thinking. Some medicines used to treat symptoms of Alzheimer's disease work by increasing the amount of acetylcholine available in the brain. Anticholinergic medicines reduce its activity.
One large observational study found that people with the highest exposure to strong anticholinergic medicines had a greater risk of dementia. But observational studies can identify patterns without proving that one factor causes another. People who take these medicines may differ from those who do not in other ways that affect their dementia risk. Some may have underlying health conditions, while others may have been prescribed medication for symptoms linked to the early stages of dementia.

A 2024 study of people with allergic rhinitis also found that dementia risk appeared to increase with higher cumulative doses of antihistamines, meaning the total amount taken over time. The association was stronger for first-generation medicines but was also seen, to a lesser extent, with newer second-generation antihistamines.

That finding was puzzling since second-generation antihistamines are less likely to cross the blood-brain barrier, the protective boundary separating the bloodstream from the brain. They also tend to have fewer anticholinergic effects.
Prolonged use of first-generation antihistamines with strong anticholinergic effects is associated with an increased risk of dementia, while evidence does not support a similar risk for second-generation antihistamines. Confounding factors, such as allergy severity and inflammation, complicate interpretation of these associations. Newer antihistamines are generally preferred due to fewer side effects and lower dementia risk.

original article.

HIV enters the brain and doesn't leave, drugs intended to reduce brain inflammation increase virus levels
HIV persists in the brain, where standard antiviral drugs have limited efficacy due to poor penetration of the central nervous system. Attempts to reduce brain inflammation by blocking integrins, specifically alpha-4, inadvertently increased viral loads by reducing killer T cell migration while allowing helper T cells to continue introducing HIV. Precision-targeted immune therapies may be necessary to control HIV-associated neurodegeneration without exacerbating viral persistence.

original article.