"Caching," is the scientific term for storing food in hidden places for later use. This behaviour is widespread across the animal kingdom, from squirrels, to crows, and wolves.

Caching behavior generally falls into one of two categories.

One is known as larder hoarding—think of a squirrel stashing nuts in just one or two places to draw from as they get through a long winter. 

 The other is known as scatter hoarding. It is where animals make smaller caches of surplus food in many different locations, reducing the chance of losing everything to a competitor or going hungry in lean seasons. It's mostly seen in wild canids such as foxes and wolves.  

This behavior in modern dogs is an instinctual remnant. It reflects the competitive feeding patterns of their ancestors who lived by hunting, for whom securing food was unpredictable, but crucial for survival. 

 Dogs appear to rely on a combination of scent and observational spatial memory to remember where they have cached special items, such as food, treats and toys.

https://theconversation.com/your-dog-is-not-a-doomsday-prepper-here...

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Fatty food smells during pregnancy may raise obesity risk in offspring

Exposure to fatty food odors during pregnancy and breastfeeding, even without maternal weight gain or high-fat intake, can alter offspring brain circuits related to reward and metabolism, increasing their risk of obesity and insulin resistance. Ingested flavoring agents with fatty odors were sufficient to trigger these effects in mice, highlighting potential implications for human metabolic health.

https://medicalxpress.com/news/2025-12-fatty-food-pregnancy-obesity...

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Why your faucet drips: Water jet breakup traced to angstrom-scale thermal capillary waves

The breakup of a water jet into droplets is primarily triggered by intrinsic thermal capillary waves—angstrom-scale surface fluctuations—rather than external disturbances or nozzle imperfections. These minute thermal oscillations are amplified by Rayleigh-Plateau instability, determining the breakup length across a wide range of jet sizes.

Stefan Kooij et al, What Determines the Breakup Length of a Jet?, Physical Review Letters (2025). DOI: 10.1103/jf6w-l5sy

How airplanes discharge static electricity

City raccoons showing signs of domestication

Urban raccoons exhibit shorter snouts compared to rural populations, a trait associated with early domestication syndrome. This morphological change is likely driven by the advantages of tameness and reduced aggression in accessing human food waste. The findings suggest that proximity to humans can induce domestication-related traits in wild species.

Artem Apostolov et al, Tracking domestication signals across populations of North American raccoons (Procyon lotor) via citizen science-driven image repositories, Frontiers in Zoology (2025). DOI: 10.1186/s12983-025-00583-1

Which gut microbes matter most? Large study ranks bacteria by health and diet links

The gut microbiome has been a rising star in the world of health science over the last several years, garnering interest from both researchers and the general public. This is mostly due to its connection to general health and diseases, like type 2 diabetes and heart disease, as well as the fact that it is a modifiable element of human health. However, the science surrounding the fascinating world of gut microbes is still developing and there is much to learn.

A new study, published in Nature, has added significantly to our understanding of the human microbiome. The study team analyzed the gut microbiome, diet and health markers from over 34,500 people in the US and UK, and linked hundreds of specific gut microbe species to key indicators of health and diet. The data come from the Zoe PREDICT program in the UK and US, which is run by the microbiome testing company Zoe.

The researchers used machine learning to link certain gut microbe species in 34,694 study participants to diet and common health risk factors such as BMI, triglycerides, blood glucose and HbA1c, as well as clinical markers that are intermediary measures of cardiometabolic health. Out of 661 non-rare microbial species, the researchers focused in on the 50 that were most favorably associated with good health and the 50 that were the most unfavorably associated with good health.

This process resulted in the development of the "ZOE Microbiome Health Ranking 2025" and "Diet Ranking 2025," used to score microbes as either favorable or unfavorable for health on a scale of 0 to 1. Those closer to zero are considered positively correlated to the health markers and those closer to one are negatively correlated. This was done for all 661 microbes studied.

The ranking system identified hundreds of gut microbe species—described as species-level genome bins (SGBs) in the paper—significantly associated with health markers and diet quality. They found that favorable microbes were more common in people with lower BMI and fewer diseases, while unfavorable microbes were more common in those with obesity and disease. A part of the study focusing on BMI, used data from 5,348 healthy individuals, and divided them into three BMI categories; healthy weight, overweight and obese.

"Meta-analysis based on linear regression on single cohorts showed that individuals with healthy weight carried, on average, 5.2 more of the 50 favorably ZOE MB health-ranked SGBs than people with obesity," the study team writes.

part1

The team also assessed whether the ZOE MB health-ranked SGBs were more abundant in participants with a defined disease. Indeed, they found that people in the control group had higher favorably ranked gut microbes than people with disease, and that those with diseases had more unfavorably ranked gut microbes than those without disease.

Dietary interventions were also found to increase favorable microbes and reduce unfavorable ones. The team analyzed data from two studies, referred to as ZOE METHOD and BIOME, in which participants either followed a personalized dietary intervention program (PDP) designed to improve the microbiome or took a prebiotic supplement. The microbiomes of these participants changed significantly by the end of the studies.

"The dietary intervention groups of both clinical trials that aimed at improving diet using different approaches (prebiotic blend for BIOME and PDP for METHOD) showed the highest number of significantly changing SGBs. Focusing on the most significant gut microbial SGBs with the largest change in relative abundance after dietary interventions, they found increasing Bifidobacterium animalis—a bacterium present in dairy-based foods and in the microbiome of people consuming larger amounts of them, an unknown Lachnospiraceae bacterium and R. hominis both previously associated with a vegan diet, and another unknown Lachnospiraceae bacterium linked to a vegetarian diet," the authors explain.

In addition to linking known bacterial species to measures of health and diet, the team also discovered many key health-associated microbes that were previously uncharacterized species.

Francesco Asnicar et al, Gut micro-organisms associated with health, nutrition and dietary interventions, Nature (2025). DOI: 10.1038/s41586-025-09854-7

Part2

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How to build a genome: Scientists release troubleshooting manual for synthetic life

Leading synthetic biologists have shared hard-won lessons from their decade-long quest to build the world's first synthetic eukaryotic genome in a Nature Biotechnology paper. Their insights could accelerate development of the next generation of engineered organisms, from climate-resilient crops to custom-built cell factories.

The Synthetic Yeast Genome Project (Sc2.0) involved a large, evolving global consortium of 200-plus researchers from more than ten institutions, who jointly set out to redesign and chemically synthesize all 16 chromosomes of baker's yeast from scratch. Macquarie University contributed to the synthesis of two of these chromosomes, comprising around 12% of the project overall.

The process for each chromosome followed the same design principles: removing unstable genetic elements; introducing molecular 'watermarks' to distinguish synthetic DNA from natural sequences; and adding the gene-shuffling system "SCRaMbLE" so researchers could rearrange genes and test their functions.

Unlike traditional genetic engineering, which tweaks existing genomes, Sc2.0 was the first to rewrite an entire genome from the ground up—all 12 million base pairs of it.

Completing all 16 synthetic chromosomes lets us understand genome function at a scale that was simply impossible before.

The chromosomes were assembled in large chunks containing thousands of base pairs, then integrated into living yeast cells step by step, relying on yeast's own cellular machinery to stitch the synthetic pieces into place.

Despite the standardized design principles, every research team encountered similar problems. The paper catalogs these 'bugs' systematically, offering future synthetic biologists a roadmap of what to avoid.

Tiny DNA watermarks, designed to be silent, occasionally disrupted gene function in unexpected ways. Some genes flagged as non-essential turned out to cause significant growth problems when removed.

Yeast cannot regenerate mitochondrial genomes from scratch, so any damage required researchers to perform a genetic rescue operation, where they identified and fixed the problem, then had to reintroduce healthy mitochondria through careful breeding.

Part 1

Teams developed and shared sophisticated debugging tools, such as "Pooled PCRtag Mapping" (which allows researchers to screen hundreds of yeast colonies simultaneously to pinpoint which genetic changes caused problems) and "CRISPR D-BUGS' (combines gene editing with selection strategies).

The lessons from yeast are already informing bold new projects.

Plants grow slowly and are far more difficult to engineer than yeast, so this project uses an ingenious approach: building the synthetic plant chromosomes inside yeast cells first, then transferring the newly constructed chromosome into plant cells.

 Building synthetic chromosomes one yeast at a time: insights from Sc2.0, Nature Biotechnology (2025). DOI: 10.1038/s41587-025-02913-4

Part 2

Small galaxies may buck the black hole trend, Chandra finds

Most smaller galaxies may not have supermassive black holes in their centers, according to a recent study using NASA's Chandra X-ray Observatory. This contrasts with the common idea that nearly every galaxy has one of these giant black holes within their cores, as NASA leads the world in exploring the secrets of how the universe works.

A team of astronomers used data from more than 1600 galaxies collected in more than two decades of the Chandra mission. The researchers looked at galaxies ranging in heft from over ten times the mass of the Milky Way down to dwarf galaxies, which have stellar masses less than a few percent of that of our home galaxy. A paper describing these results has been published in The Astrophysical Journal.

The team has reported that only about 30% of dwarf galaxies likely contain supermassive black holes.

As material falls onto black holes, it is heated by friction and produces X-rays. Many of the massive galaxies in the study contain bright X-ray sources in their centers, a clear signature of supermassive black holes in their centers. The team concluded that more than 90% of massive galaxies—including those with the mass of the Milky Way—contain supermassive black holes.
However, smaller galaxies in the study usually did not have these unambiguous black hole signals. Galaxies with masses less than three billion suns—about the mass of the Large Magellanic Cloud, a close neighbor to the Milky Way—usually do not contain bright X-ray sources in their centers.

The researchers considered two possible explanations for this lack of X-ray sources. The first is that the fraction of galaxies containing massive black holes is much lower for these less massive galaxies. The second is the amount of X-rays produced by matter falling onto these black holes is so faint that Chandra cannot detect it.

To reach their conclusion, the researchers considered both possibilities for the lack of X-ray sources in small galaxies in their large Chandra sample. The amount of gas falling onto a black hole determines how bright or faint they are in X-rays. Because smaller black holes are expected to pull in less gas than larger black holes, they should be fainter in X-rays and often not detectable. The researchers confirmed this expectation.

However, they found that an additional deficit of X-ray sources is seen in less massive galaxies beyond the expected decline from decreases in the amount of gas falling inwards. This additional deficit can be accounted for if many of the low-mass galaxies simply don't have any black holes at their centers. The team's conclusion was that the drop in X-ray detections in lower mass galaxies reflects a true decrease in the number of black holes located in these galaxies.
This result could have important implications for understanding how supermassive black holes form. There are two main ideas: In the first, a giant gas cloud directly collapses into a black hole, which contains thousands of times the sun's mass from the start. The other idea is that supermassive black holes instead come from much smaller black holes, created when massive stars collapse.
The formation of big black holes is expected to be rarer, in the sense that it occurs preferentially in the most massive galaxies being formed, so that would explain why we don't find black holes in all the smaller galaxies, say the researchers.

Fan Zou et al, Central Massive Black Holes Are Not Ubiquitous in Local Low-mass Galaxies, The Astrophysical Journal (2025). DOI: 10.3847/1538-4357/ae06a1

Part 2

Warblers borrow color-related genes from evolutionary neighbours, study finds

Wood warblers, also called New World warblers, are some of the most colorful birds in North America, with more than a hundred species in the family ranging in color from yellow, orange and red to blue, green and pink. A new study led by researchers at Penn State has uncovered several instances of the birds passing color-related genes to other species of wood warblers, including those that are not closely related.

This glimpse into the hidden evolutionary dynamics of these songbirds may help explain why some species display certain colors as well as how the group diversified into so many different species in such a relatively short evolutionary time, the researchers said.

A paper describing the research appeared Dec. 11 in the journal PLOS Biology.

It turns out that some of these birds may have borrowed colors from their neighbors, rather than evolving them independently. Scientists previously found evidence that a particular color-related gene had been shared between species within the same genus, which is one notch up on the taxonomic ladder, but now they show that there is gene movement from species in one genus to another. That means some genetic funny business was going on with these warblers millions of years ago.

In addition to the pigment melanin, which produces brown and black plumage, the colors of wood warblers are influenced by carotenoid pigments, which are responsible for bright yellow, red and orange plumage. The research team collected DNA from 400 warblers across 100 species and six subspecies, focusing on three main genes related to carotenoid pigments.

The team compared an evolutionary tree of the warblers—built using their entire genomes and representing the overall relationships among the birds—with trees they created independently for each of the three carotenoid-related genes. These gene-specific trees show similarities and differences of the individual gene across the family, and discrepancies between the trees suggest where gene exchanges may have occurred. Statistical follow-up tests confirmed the gene exchanges, which the researchers said resulted from a process called introgression.

Part 1

When birds of two different species mate, their hybrid offspring inherit genes from both parents. When that hybrid goes on to mate with an individual of one of its parent species, it can pass on genes from the other. Over several generations, the genetic material from one species can be incorporated into the other, which is called introgression.

The  research group previously identified introgression of a gene called BCO2 among several species of wood warblers within the genus Setophaga, but it seemed like the version of the gene that was getting passed around might have originated from outside that group. Here, they confirmed that this version of the gene came from outside the genus and found that it has been exchanged between species of a different genus on multiple occasions.

The gene beta-carotene oxygenase 2 (BCO2), when turned on, produces a protein that breaks down yellow carotenoids, resulting in more white or gray coloration. When turned off, BCO2 results in the accumulation of yellow carotenoids and thus yellow plumage.

The researchers found evidence of introgression of BCO2 among several wood warbler species, including from a species within the genus Leiothlypis to multiple Setophaga species as well as to multiple species in the genus Cardellina. They also observed introgression of BCO2 from the genus Vermivora to Geothlypis, though the order and exact timing of these exchanges remain unclear.

Scientists think the initial introgression events from Leiothlypis occurred between half a million to two million years ago—while the donor and recipient species themselves diverged several million years before that.

But the 'borrowed' version of this gene has stuck around all that time, even as the species themselves evolved and split.

While introgression of BCO2 from Leiothlypis to other species may have occurred millions of years ago, the researchers suggested that introgression into one species, the red-faced warbler, is not only more recent, but is currently in progress, as not all members of the species they sampled contained the borrowed version of the gene.

A colorful legacy of hybridization in wood-warblers includes frequent sharing of carotenoid genes among species and genera, PLOS Biology (2025). DOI: 10.1371/journal.pbio.3003501

Part 2

Scientists teach helices to switch shapes
Synthetic molecules can be programmed to form specific helical structures by embedding instructions in their sequence, enabling control over helix type and the ability to switch shapes in response to environmental changes. These helices possess internal cavities capable of trapping persistent pollutants like perfluorinated sulfonates, indicating potential for adaptive materials and environmental applications.

Dimitri Delcourt et al, Programmable Assembly of Multistranded Helices in Water, Nature Communications (2025). DOI: 10.1038/s41467-025-67227-0

Lab-developed mosquitoes prevent malaria parasite development, paving way for future field trials

In a new study published in Nature, scientists have successfully developed genetically modified mosquitoes in Tanzania that block the transmission of malaria.

In 2023, Transmission Zero's leading researchers created the first transgenic mosquito strain ever developed in Africa, in Tanzania. Its latest research offers a new solution by genetically modifying Anopheles gambiae mosquitoes (malaria-carrying mosquitoes) to block the development of malaria parasites, effectively reducing their ability to transmit the disease.
This approach allows these precise changes in the mosquitoes' ability to carry the malaria parasite to be passed down from one mosquito generation to the next.

These findings on Anopheles gambiae are the pathfinder for the technology to be extended to other equally important malaria vectors such as Anopheles arabiensis and Anopheles funestus, as well as vectors of diseases such as dengue and chikungunya.

Conducted entirely under containment, the study introduced antimalarial traits—naturally occurring molecules from frogs and honeybees—into local mosquito populations. The modified mosquitoes effectively prevented Plasmodium falciparum, the primary malaria parasite in Africa, from developing, creating a significant barrier to transmission.

While the results are promising, further research is required before field trials can begin.

Tibebu Habtewold et al, Gene-drive-capable mosquitoes suppress patient-derived malaria in Tanzania, Nature (2025). DOI: 10.1038/s41586-025-09685-6

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Farm-living families develop earlier immune maturation against food allergies, study finds

Children who grow up in farming communities have long been known to develop far fewer allergies than their urban peers. A new study offers one possible reason why: their immune systems may mature faster, and breast milk appears to play an important supporting role.

What this study shows is that their B cell and antibody responses are essentially ahead of schedule compared to urban infants. Their immune systems seem better equipped, earlier in life, to handle foods and other exposures without overreacting.

Farm-exposed infants had more memory and IgG+ B cells, suggesting earlier maturation of the antibody-producing system. They also had higher levels of IgG and IgA antibodies in blood, saliva, and stool, and higher IgA levels in human milk from their mothers. Taken together, the data point to a more robust and active antibody system in infants growing up in a traditional farming lifestyle.

Researchers saw a continuum: the more egg-specific antibodies in breast milk, the less likely babies were to develop egg allergy.

The  data suggest there may be particular benefit when mothers have high levels of food-specific antibodies in their milk. Not every mother does, and that could help explain why results have been mixed on the association between breastfeeding and food allergy.

Why do Mennonite mothers have more egg-specific antibodies? One likely factor is diet. Old Order Mennonite families typically raise their own chickens and eat eggs frequently. That repeated exposure appears to boost mothers' antibody levels against egg proteins, which then show up both in the bloodstream and in breast milk.

Just as an infection or a vaccine can boost your antibody levels, regularly eating certain foods could do the same.

The study also found differences in antibodies to other environmental allergens at birth. OOM infants were born with higher cord blood levels of IgG and IgG4 antibodies to dust mites and horse, reflecting their mothers' exposures, while urban infants had higher antibodies to peanut and cat. The team detected several food antigens in cord blood, and even antigen-specific IgA at birth, suggesting that in-utero exposure to food proteins may also shape early immunity.

Part 1

While maternal diet and breast milk antibodies are central to the new paper, the researchers emphasize that the "farm effect" is almost certainly multifactorial and can vary between individuals.

Courtney M. Jackson et al, Farm exposure in infancy is associated with elevated systemic IgG₄, mucosal IgA responses, and lower incidence of food allergy, Science Translational Medicine (2025). DOI: 10.1126/scitranslmed.ads1892

Part 2

Fake participants and bots threaten quality of online research data
Online qualitative research faces risks from fraudulent participants, including bots and ineligible humans, which can compromise data quality. Identifying and removing such responses is challenging but essential. Strategies to mitigate these risks include careful recruitment planning, screener surveys, and community-engaged methods to enhance data integrity.

Devon Ziminski et al, Preventing and mitigating fraudulent research participants in online qualitative violence and injury prevention research, BMJ Open Quality (2025). DOI: 10.1136/bmjoq-2025-003706

Is The Y Chromosome Vanishing?

The Y chromosome has long been rumored to be vanishing. So what does that mean for the future of men?
Some evolutionary biologists  say what’s in store for the human species.

They think the Y chromosome is running out of time.
Already, it’s lost 97 percent of its ancestral genes in the last 300 million years.

At that rate, it could disappear in another 6 million years, and a new sex gene may take its place.

Still, not everyone agrees that the Y chromosome is doomed. A potent scientific debate is brewing.

https://www.sciencealert.com/is-the-y-chromosome-vanishing-a-new-se...

Concrete with a human touch: Can we make infrastructure that repairs itself?
Self-healing concrete incorporates materials such as bacteria or chemical agents that can autonomously repair cracks, improving durability and reducing maintenance costs. Bacteria-based methods rely on microbiologically induced calcite precipitation but are slow and limited to small cracks, while chemical-based approaches can address larger cracks more rapidly. Encapsulation of healing agents is a promising strategy, though standardization and integration challenges remain 

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Helping crops survive in saltwater: Mangroves reveal key cellular traits
Mangroves possess unusually small cells and thicker cell walls compared to inland relatives, traits that enhance mechanical strength and prevent wilting under saltwater exposure. These cellular adaptations have evolved repeatedly in saline environments, suggesting that modifying cell size and wall properties could be a promising approach for developing salt-tolerant crops 

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Microbial molecule that disarms inflammation discovered, offering new diabetes treatment strategy
Trimethylamine (TMA), a metabolite produced by gut bacteria from dietary choline, directly inhibits the immune protein IRAK4, reducing inflammation and improving insulin sensitivity in models of type 2 diabetes. Blocking IRAK4, either genetically or pharmacologically, yields similar benefits, highlighting a potential therapeutic target for diabetes management 

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Immunotherapy works for sepsis thanks to precision approach
Tailoring immunotherapy to the specific immune status of sepsis patients—either overactive immunity or immune paralysis—improves clinical outcomes compared to standard care. Biomarker-guided selection enables targeted treatment, leading to faster organ function recovery and infection resolution in these subgroups, representing about 25% of sepsis cases 

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Pancreatic cancer cells 'speak the language' of organs they will later invade, study reveals
Pancreatic cancer cells at the primary tumor site exhibit gene expression patterns resembling those of the organs they will later invade, predisposing them to metastasize to specific locations. This organ-specific adaptation occurs without a single identifiable genetic mutation and may also be present in other cancer types. These findings could inform future strategies for predicting and preventing metastasis 

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How brain activity changes throughout the day: Findings offer clues to fatigue and mental health
Brain activity patterns shift throughout the day, with neuronal activity moving from subcortical regions upon waking to cortical areas as wakefulness continues. These dynamic changes are reversed during sleep. The findings provide a framework for identifying objective markers of fatigue and have potential implications for understanding mental health and developing new assessment tools 

Decoding the chemistry of life: Maximum entropy reveals how mutations alter enzymes and drive drug resistance
Maximum entropy, a statistical measure, enables accurate prediction of how mutations alter enzyme activity and drive drug resistance, particularly in viruses with constrained evolutionary pathways like hepatitis C. The approach outperforms traditional simulations in speed and accuracy, effectively forecasting disease-related mutations in proteins such as myosin, and aiding in enzyme design and disease prediction 

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Blinking less may mean brain is working harder, study shows
Blink rates decrease when individuals focus on understanding speech in noisy environments, indicating that reduced blinking reflects increased cognitive effort. This suppression of blinking occurs regardless of lighting conditions, suggesting cognitive demand, not visual input, drives the effect. Blink timing aligns with periods of salient information, supporting its use as a marker of mental workload. 

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How the 'hypnagogic state' of drowsiness could enhance your creativity
The hypnagogic state, the transitional phase between wakefulness and sleep, is linked to increased creativity, as it allows ideas from the subconscious to surface when conscious mental activity is reduced. This state enhances cognitive flexibility and openness, and practices like meditation or conscious napping can help harness its creative potential. Recording ideas immediately is crucial, as insights are easily forgotten 

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Harnessing the power of clay to protect communities from toxins
Clay-based materials act as effective sorbents, binding toxins such as aflatoxins, heavy metals, PFAS, and pesticides to prevent their absorption in humans, animals, and plants. These clays can be ingested or applied topically, and their use extends to environmental remediation, including soil and air purification, offering practical solutions for reducing exposure to hazardous chemicals. 

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Trust in science is low among minorities for a reason, research finds
Trust in science among underrepresented groups in the U.S., such as African Americans and women, remains low, partly due to a lack of diversity within scientific fields and historical abuses like the Tuskegee study. People are more likely to trust scientists who share their demographic background, but these groups are underrepresented in STEM. This trust gap can negatively impact health outcomes, as seen during the COVID-19 pandemic. Reducing social distance between scientists and society may improve trust 

Genetic overlap of 14 psychiatric disorders explains why patients often have multiple diagnoses

An international collective of researchers is delivering new insights into why having multiple psychiatric disorders is the norm rather than the exception. In a study published recently in the journal Nature, the team provides the largest and most detailed analysis to date on the genetic roots shared among 14 conditions.

The majority of people diagnosed with a psychiatric disorder will ultimately be diagnosed with a second or third disorder in their lifetime, creating challenges for defining and treating these conditions. While a person's environment and lived experience influence their risk for developing multiple disorders, their genetic makeup can also play a significant role.

By analyzing data from over 6 million individuals, the working group mapped the genetic landscape of 14 psychiatric conditions and revealed five families of disorders with high levels of genetic overlap. The results mark an important step toward understanding the genetic connections among psychiatric disorders and could ultimately help clinicians better serve their patients.

Analysis of genetic data from over 6 million individuals reveals that 14 psychiatric disorders cluster into five groups with significant genetic overlap. Major depression, anxiety, and PTSD share about 90% of genetic risk, while schizophrenia and bipolar disorder share 66%. Shared genetic variants and expression patterns help explain frequent comorbidity among these conditions.

Through statistical modeling, the researchers found that the 14 disorders could be divided into these five groups based on genetic similarities:

• Compulsive disorders: obsessive-compulsive disorder, anorexia nervosa and, to a lesser extent, Tourette disorder and anxiety disorders.
• Internalizing disorders: major depression, anxiety disorders and post-traumatic stress disorder.
• Neurodevelopmental disorders: autism spectrum disorder, attention-deficit/hyperactivity disorder and, to a lesser extent, Tourette disorder.
• Schizophrenia and bipolar disorder
• Substance use disorders: opioid use disorder, cannabis use disorder, alcohol use disorder and nicotine dependence.

Andrew D. Grotzinger et al, Mapping the genetic landscape across 14 psychiatric disorders, Nature (2025). DOI: 10.1038/s41586-025-09820-3

Abdel Abdellaoui, Shared genetic risk in psychiatric disorders, Nature (2025). DOI: 10.1038/d41586-025-03728-8 , doi.org/10.1038/d41586-025-03728-8

Ghostly solar neutrinos caught transforming carbon atoms deep underground

Solar neutrinos have been directly observed transforming carbon-13 nuclei into nitrogen-13 within the SNO+ underground detector. Using a delayed coincidence method, 5.6 events were detected over 231 days, matching the 4.7 events expected from neutrino interactions. This marks the first direct measurement of this low-energy neutrino-induced reaction, advancing the study of rare atomic processes.

SNO+ Collaboration et al, First Evidence of Solar Neutrino Interactions on ¹³C, Physical Review Letters (2025). DOI: 10.1103/1frl-95gj On arXiv: DOI: 10.48550/arxiv.2508.20844

How the immune system stalls weight loss

Neutrophils, a type of immune cell, infiltrate fat tissue during physiological stress and release signals that suppress fat breakdown, helping to prevent excessive weight loss. This mechanism, observed in both mouse models and human data, involves specific inflammatory pathways and is more active in obese individuals. The findings highlight a key role for the immune system in regulating energy balance.

In a study published in Nature, a research team demonstrates that when the body is exposed to physiological stressors, such as low temperature, neutrophils—a type of white blood cell—infiltrate fat tissue and release signals that slow fat breakdown.

The researchers hypothesize that this mechanism helped our early human ancestors preserve vital energy stores when food was scarce or when exposed to prolonged periods of cold. Today, the findings could help yield new approaches to managing obesity and other metabolic disorders.

White adipose tissue (WAT)—commonly known as body fat—plays a vital role in maintaining energy balance by storing excess energy and releasing it as needed during periods of fasting, cold or other metabolic stress. These biochemical processes are carefully managed by the body in order to prevent excessive fat loss, which can be very dangerous.

Until now, the mechanisms that protect the body against runaway fat burning in times of stress have remained unclear.

To address this, the researchers studied a combination of mouse models and human genetic data.

Key findings include:
In mouse models, activating the sympathetic nervous system triggered a rapid influx of neutrophils into visceral fat, the fat surrounding vital organs. This neutrophil recruitment depended on both ongoing fat breakdown and activation of specific inflammatory pathways in fat cells.
Neutrophils arriving in the fat tissue produced signaling molecules that suppressed further fat loss in surrounding tissue.
When either these molecules or neutrophils themselves were depleted, mice experienced increased fat breakdown under metabolic stress.
In obese individuals, genes involved with this pathway were more active.
These findings reveal an unexpected physiological partnership between fat cells and immune cells, demonstrating that the immune system is crucial not only for fighting infection but also for maintaining energy balance.

The study also provides new insight into the underlying metabolism of obesity and other metabolic disorders. Targeting this newly discovered pathway may eventually offer new strategies for treating obesity, metabolic syndrome or conditions involving unintended weight loss.

Seunghwan Son et al, Neutrophils preserve energy storage in sympathetically activated adipocytes, Nature (2025). DOI: 10.1038/s41586-025-09839-6 , doi.org/10.1038/s41586-025-09839-6

Immune system's 'on-off' switch may hold answers for cancer and autoimmunity

A single signaling pathway controls whether immune cells attack or befriend cells they encounter while patrolling our bodies, researchers have found. Manipulating this pathway could allow researchers to toggle the immune response to treat many types of diseases, including cancers, autoimmune disorders and those that require organ transplants.

The research, which was conducted in mice, illuminates the mechanism of an important immune function that prevents inappropriate attacks on healthy tissue. Called peripheral immune tolerance, the key cellular players, known as regulatory T cells (or Tregs), were first described in the late 1990s in a series of discoveries that were recently recognized with the 2025 Nobel Prize in physiology or medicine.

The work is published in the journal Nature.

The findings extend those of a related study published in Science by the same researchers that described a surprising new role for a molecule known for decades to promote red blood cell formation.

Now it is clear that this molecule, erythropoietin, or EPO, is the lynchpin controlling how our immune systems react to real or perceived threats—acting through immune cells called dendritic cells.

The critically important building of immune tolerance to "self" is a two-step process. The first, called central immune tolerance, occurs in the bone marrow and the thymus, where B cells and T cells undergo a first round of selection to eliminate or reprogram self-reactive cells before they are released into the bloodstream.
The second, peripheral immune tolerance, serves as a backup to screen circulating cells that escape the first culling.

The stakes are high. An overly enthusiastic immune system that attacks healthy tissues leads to autoimmune diseases like rheumatoid arthritis, multiple sclerosis, lupus and diabetes. Conversely, a too complacent, or tolerant, response allows cancer cells to escape immune destruction, instead of sending them on their way with a handshake and a pat on the back.

Part 1

The immune system's response—threatening or welcoming—is governed by the Tregs, which tamp down inappropriate attack impulses of other immune cells called T and B cells.
The researchers used an experimental approach first identified in mice and subsequently in humans in which irradiating the thymus, spleen and lymph nodes—all places in the body where immune cells hang out—kills off many of the T cells and B cells while leaving antigen-presenting cells such as dendritic cells relatively unscathed.

The treatment, called total lymphoid irradiation, reprograms the recipient's immune system to permanently tolerate genetically mismatched transplanted cells or organs.

But dendritic cells don't act alone and instead recruit other immune cells, including T cells, to carry out their missions.

"All T cells, including Tregs, must first be 'presented' with a structure called an antigen that is recognized by their receptors for the cells to develop into mature T cells that either attack a target or suppress the immune response to that target," Engleman said. "Dr. Zhang and I reasoned that this process of tolerance or activation must be initiated by antigen-presenting cells."

The most powerful antigen-presenting cells in the body are called type 1 dendritic cells, which engulf dead or dying cells or pathogens and display bits of those cells like immunological fishing lures for T or B cells.

To learn how dendritic cells are involved in the development of immune tolerance, Zhang and Engleman decided to investigate whether and how the genes they express change in mice after total lymphoid irradiation.

They found that the gene for the EPO receptor is expressed at much higher levels in the dendritic cells of irradiated animals, and that the levels of EPO are elevated in the animals' blood circulation.
Part 2

Normally, this would have been a huge surprise. EPO is well known as the primary instigator of red blood cell production, and it was named for this function (erythro meaning "red" and poiein meaning "to produce").

But earlier in 2025,  the researchers showed that cancer cells in immunologically tolerated, or "cold," tumors trick the immune system by making EPO and releasing it into the tumor environment where it binds to a type of immune cell called macrophages and causes these cells to become immunosuppressive. So, they knew that EPO has a second role as a master immune regulator.

When they genetically manipulated the mice to remove the ability of the dendritic cells to express the EPO receptor, the animals rejected transplants of unmatched tissue after total lymphoid irradiation, showing conclusively that the EPO signaling pathway is necessary for the development of immune tolerance. But there was another intriguing finding.

"What was quite a surprise  is that when you remove or block the EPO receptor on the dendritic cells, you don't just block the development of tolerance.

"Instead, you have now converted these dendritic cells into super stimulators, or powerful activators of immune response. There is a dual opportunity to not just induce tolerance to treat autoimmune diseases, but also to trigger a strong immune response to cancer cells or to life-threatening infections."

Essentially, dendritic cells continuously sample their environment by capturing and swallowing dead or dying cells (either self or non-self) as well as pathogens and displaying fragments of the cells on their surfaces to be recognized by many types of T cells, including killer T cells, helper T cells or Tregs.

When EPO interacts with its EPO receptors on the dendritic cells, it causes the dendritic cells to embark on a series of maturation steps that cause them to promote tolerance and selectively activate Tregs that tamp down any immune response to that antigen.

"This mechanism is not only required for physiological tolerance that prevents autoimmune disease, but it is often hijacked by cancers and probably some infectious pathogens, too, enabling their ability to evade immune attack.

Conversely, removing the EPO receptor from dendritic cells resulted in tumor regression in mice with immune-resistant melanoma or colon cancer tumors.

"It's fascinating that this fundamental mechanism took so long to discover. "It's even possible that this is the primary function of EPO, and that its effect on red blood cell formation is secondary. There is no doubt these findings will light many research fires."

Edgar Engleman, Erythropoietin receptor on cDC1s dictates immune tolerance, Nature (2025). DOI: 10.1038/s41586-025-09824-z. www.nature.com/articles/s41586-025-09824-z

Part 3

**

Misinformation across nature

From claims that vaccines don't work to manipulated images and deliberately misrepresenting what politicians say, social media is often rife with misinformation. But far from being a recent phenomenon, there is nothing new about so-called "fake news," according to a new paper published in the journal Interface. Researchers argue that misinformation is an inherent and inevitable property of biological systems, from bacteria to birds and human societies.

Social communication is a key part of social evolution and collective behavior. It is how an organism learns about its immediate environment without having to rely on risky, trial-and-error or how a bacterium coordinates its behavior with its neighbors to launch a collective defense. However, these social connections can also act as channels for misinformation.

Researchers  reviewed decades of empirical and theoretical studies of misinformation in biological systems to see where and how it happens in nature. They found plenty of examples, such as a bird giving a false alarm call, causing the entire flock to flee, an animal population copying outdated migratory paths and even deceptive signalling in bacteria.

To define and measure misinformation across different systems, the study authors developed mathematical models to investigate it in any species. This will allow scientists to understand how accurate an organism's existing beliefs are and the extent to which information from other organisms shifts those beliefs. Working with these models led the team to conclude that misinformation is a fundamental feature of all biological communication, not a bug, failure, or other pathology.

Socially transmitted misinformation is likely to be a ubiquitous feature of biological communication, and should therefore be viewed as a fundamental part of social, ecological and evolutionary systems, rather than as a pathology that somehow lies apart from the normal functioning of these systems, the authors explain in their research paper.

If we can understand the impact of this misinformation, this knowledge helps us develop strategies to control misinformation in both human and biological systems.

Ling-Wei Kong et al, A brief natural history of misinformation, Journal of the Royal Society Interface (2025). DOI: 10.1098/rsif.2025.0161

A hormone can access the brain by 'hitchhiking' on extracellular vesicles, researchers discover
Extracellular vesicles (EVs) in blood can transport the hormone precursor proopiomelanocortin (POMC), especially after vigorous exercise, increasing its association with EVs fourfold. EV-bound POMC crosses blood vessel barriers, including the blood-brain barrier, more efficiently than free POMC, suggesting a mechanism for hormone delivery to the brain and potential implications for metabolism and stress response.

Hightower, Cheryl E. et al, Physical exercise increases binding of POMC to blood extracellular vesicles, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2525044122. doi.org/10.1073/pnas.2525044122

Typhoons vacuum microplastics from ocean and deposit them on land, study finds
Typhoons and similar storms rapidly transfer microplastics from the ocean to land, with deposition rates increasing by up to an order of magnitude during storm events. Analysis confirms these particles originate from marine sources, not local environments. This process links plastic pollution and climate change, as stronger storms fueled by warming oceans transport more microplastics inland.

Taiseer Hussain Nafea et al, Microplastics from Ocean Depths to Landfall: Typhoon-Induced Microplastic Circulation in a Warming Climate, Environmental Science & Technology (2025). DOI: 10.1021/acs.est.5c11101

Climate change can affect human diseases in widespread and varied ways

As the planet edges towards 1.5°C of global warming, a new study has revealed that we still have only a limited understanding of how climate change is reshaping the risk of infectious diseases that pass from animals to humans.

The research shows that a warmer world will alter weather patterns, transform habitats and shift where many animals live, likely bringing people and wildlife into closer proximity and increasing opportunities for zoonotic diseases to "spill over." However, the exact impacts are extremely hard to predict.

By reviewing hundreds of scientific studies, the team was able to extract detailed climate-disease data for 53 zoonotic diseases—around 6% of the 816 known zoonotic diseases that affect humans. Even for these relatively well-studied diseases, responses to climate change are highly variable.
Overall, zoonotic diseases were found to be sensitive to climate, with temperature showing the clearest links. Higher temperatures were almost twice as likely to increase disease risk as to decrease it, particularly for zoonotic infections spread by mosquitoes. But this pattern was far from universal, and for other climate factors, such as rainfall and humidity, the picture was even more mixed.

The study found that zoonotic diseases are generally climate-sensitive but respond in a variety of ways depending on the disease, the animal host and the local environment. The paper is published in the Proceedings of the National Academy of Sciences.

Temperature showed the strongest and most consistent links. In many cases, warming increases risk for instance, by speeding up the development of mosquitoes or boosting rodent populations. However, even for a single disease, the response to temperature may change depending on how warm it already is, or which species are involved.

Artur Trebski et al, Climate sensitivity is widely but unevenly spread across zoonotic diseases, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2422851122

Firefighter gear contains potentially hazardous flame retardants, study shows

Firefighter turnout gear manufactured between 2013 and 2020 contains both PFAS and brominated flame retardants, with newer gear marketed as non-PFAS treated showing low or undetectable PFAS but higher extractable levels of brominated flame retardants, particularly decabromodiphenyl ethane (DBDPE). These chemicals may pose health risks, highlighting the need for transparency in gear composition.

Environmental Science & Technology Letters (2025)

The North Pole keeps moving. Here's how that affects Santa's holiday travel and yours
Earth has two North Poles: the geographic North Pole, marking the axis of rotation, and the magnetic North Pole, which compasses and navigation devices use. The magnetic North Pole moves due to fluid motion in Earth's outer core, with its speed increasing significantly since 1990. Accurate navigation requires correcting for the difference, known as magnetic declination.

The geographic North Pole, also called true north, is the point at one end of the Earth’s axis of rotation.

Earth’s magnetic North Pole is different.

Over 1,000 years ago, explorers began using compasses, typically made with a floating cork or piece of wood with a magnetized needle in it, to find their way. The Earth has a magnetic field that acts like a giant magnet, and the compass needle aligns with it.

The magnetic North Pole is used by devices such as smartphones for navigation – and that pole moves around over time.

The movement of the magnetic North Pole is the result of the Earth having an active core. The inner core, starting about 3,200 miles below your feet, is solid and under such immense pressure that it cannot melt. But the outer core is molten, consisting of melted iron and nickel.

Heat from the inner core makes the molten iron and nickel in the outer core move around, much like soup in a pot on a hot stove. The movement of the iron-rich liquid induces a magnetic field that covers the entire Earth.

As the molten iron in the outer core moves around, the magnetic North Pole wanders.

For most of the past 600 years, the pole has been wandering around over northern Canada. It was moving relatively slowly, around 6 to 9 miles per year, until around 1990, when its speed increased dramatically, up to 34 miles per year.

It started moving in the general direction of the geographic North Pole about a century ago. Earth scientists cannot say exactly why other than that it reflects a change in flow within the outer core.

https://theconversation.com/the-north-pole-keeps-moving-heres-how-t...

Living rocks in South Africa rapidly absorb carbon

South Africa is home to some of the oldest evidence of life on Earth, contained in rocky, often layered outcroppings called microbialites. Like coral reefs, these complex "living rocks" are built up by microbes absorbing and precipitating dissolved minerals into solid formations.

A new study suggests that these microbialites aren't just surviving—they're thriving.

A paper  published in Nature Communications, quantifies how microbialites along the South African coast take up carbon and turn it into fresh layers of calcium carbonate. They show how these structures utilize photosynthesis and chemical processes to absorb carbon day and night, relating those rates for the first time to the genetic makeup of the microbial community.

The findings highlight just how efficient these microbial mats are at removing dissolved carbon from their environment and sequestering it into stable mineral deposits.

Researchers found that these systems were precipitating calcium carbonate rapidly, estimating that the structures can grow almost two inches vertically every year.

More surprising was the finding of carbon uptake day and night. These systems have long been assumed to be driven solely by photosynthesis.

After repeating their experiments several times, the researchers confirmed that the microbes are utilizing metabolic processes other than photosynthesis to absorb carbon in the absence of light, similar to how microbes living in deep-sea vents survive.

Based on daily rates of carbon uptake, the team estimates that these microbialites can absorb the equivalent of nine to 16 kilograms of carbon dioxide every year per square meter.

Rachel E. Sipler et al, Integration of multiple metabolic pathways supports high rates of carbon precipitation in living microbialites, Nature Communications (2025). DOI: 10.1038/s41467-025-66552-8

Emerging science: The positive health benefits of microbes

Viruses and bacteria get a bad rap around the world, but now  experts are identifying the positive "upside" of powerful benefits that microbes have on human health.

They  presented a timely reminder of these 'invisible friends' in a new article published in Microbial Biotechnology, underlining the benefits of moving away from a threat-centered view of microbes and biogenic compounds.

The article introduces the "Database of Salutogenic Potential," a world-first prototype open-access repository that catalogs microbes and natural compounds linked to positive health outcomes.

Emerging evidence shows that exposure to diverse environmental microbiomes and natural biochemical products also promotes health and resilience. Rather than viewing biodiversity as something to be eliminated, contemporary approaches recognize the vital role of diverse ecosystems in creating salutogenic, or health-promoting, environments.

By consolidating this data, researchers aim to rebalance the story of microbes—highlighting not only what makes us sick, but also what keeps us well. After all, health is not merely the absence of disease. The implications are far-reaching—from designing healthier cities and schoolyards to guiding ecosystem restoration and rethinking green infrastructure.

Salutogenic microbes—those that promote health—and beneficial biochemical compounds have received comparatively little attention despite their important roles in regulating immune function and metabolic processes, suppressing disease, mitigating stress and supporting ecosystem resilience.

For well over a century,  microbes in the air have mainly been studied as threats—causes of infection, disease and contamination. While this pathogen-centric lens has saved countless lives, it also risks overlooking the invisible biodiversity that actively supports human and planetary health. Just as biodiversity loss threatens our health, restoring microbial and biochemical richness could be a key to healthier futures.

The researchers have identified 124 potentially salutogenic microbial taxa and 14 biochemical compounds (from soil bacteria to plant-derived phytoncides) associated with benefits ranging from immune regulation to stress reduction.

Jake M. Robinson et al, Mapping and Cataloguing Microbial and Biochemical Determinants of Health: Towards a 'Database of Salutogenic Potential', Microbial Biotechnology (2025). DOI: 10.1111/1751-7915.70243

A mild brain injury can trigger Alzheimer's

Mild traumatic brain injury disrupts brain lymphatic vessel function, impairing waste clearance and accelerating harmful tau protein accumulation associated with Alzheimer's disease. Early intervention to restore lymphatic drainage in laboratory models prevented tau buildup and brain degeneration, suggesting a potential therapeutic strategy to reduce Alzheimer's and other neurodegenerative risks after head trauma.

Ana Royo Marco et al, Therapeutic VEGFC treatment provides protection against traumatic-brain-injury-driven tauopathy pathogenesis, Cell Reports (2025). DOI: 10.1016/j.celrep.2025.116521

40% of MRI signals do not correspond to actual brain activity, study suggests
Approximately 40% of fMRI signals do not accurately reflect neuronal activity, as increased signals can correspond to reduced brain activity and vice versa. Oxygen consumption in active brain regions often rises without increased blood flow, indicating more efficient oxygen extraction rather than greater perfusion. These findings challenge standard interpretations of fMRI data, especially in studies of brain disorders.

For almost three decades, functional magnetic resonance imaging (fMRI) has been one of the main tools in brain research. Yet a new study published in Nature Neuroscience fundamentally challenges the way fMRI data have so far been interpreted with regard to neuronal activity.

According to the findings, there is no generally valid coupling between the oxygen content measured by MRI and neuronal activity.

Researchers found that an increased fMRI signal is associated with reduced brain activity in around 40% of cases. At the same time, they observed decreased fMRI signals in regions with elevated activity.

This contradicts the long-standing assumption that increased brain activity is always accompanied by an increased blood flow to meet higher oxygen demand. Since tens of thousands of fMRI studies worldwide are based on this assumption, these new results could lead to opposite interpretations in many of them.

According to the researchers, these insights also affect the interpretation of research findings in brain disorders. Many fMRI studies on psychiatric or neurological diseases—from depression to Alzheimer's—interpret changes in blood flow as a reliable signal of neuronal under- or over-activation.

Given the limited validity of such measurements, this must now be reassessed. Especially in patient groups with vascular changes—for instance, due to aging or vascular disease—the measured values may primarily reflect vascular differences rather than neuronal deficits, say the researchers.

The researchers therefore propose complementing the conventional MRI approach with quantitative measurements. In the long term, this combination could form the basis for energy-based brain models: rather than showing activation maps that depend on assumptions about blood flow, future analyses could display values indicating how much oxygen—and therefore energy—is actually consumed for information processing.

Samira M. Epp et al, BOLD signal changes can oppose oxygen metabolism across the human cortex, Nature Neuroscience (2025). DOI: 10.1038/s41593-025-02132-9

Biodegradable dishes could transfer gluten to foods, posing health risk to gluten-sensitive individuals
Some biodegradable tableware made from wheat by-products can contain gluten and transfer it to foods and drinks at levels exceeding gluten-free regulatory thresholds, particularly into liquids. This poses a potential health risk for individuals with celiac disease or gluten sensitivity, as such products are not required to carry allergen labels.

In 30-minute experiments conducted by researchers, gluten-free foods were placed on the different tableware items at room temperature. The foods' gluten contents were measured and compared against the gluten-free (less than 20 ppm) and low-gluten (less than 100 ppm) regulatory thresholds set by the European Union and the U.S. Food and Drug Administration. Only the gluten-containing plate passed protein into omelet, rice, milk and vegetable cream samples. Significantly less gluten transferred into the solid foods than into the liquids:

• Rice: up to 17 ppm, below the gluten-free threshold.
• Omelet: up to 30 ppm, below the low-gluten threshold.
• Milk: up to 240 ppm, over the low-gluten threshold.
• Vegetable cream: up to 2,100 ppm, over the low-gluten threshold.

In some cases, microwaving foods in the dish reduced gluten contamination compared to room temperature samples, and the researchers hypothesize it is because heat denatures the protein and disrupts its transfer into foods.

The researchers urge mandatory gluten labeling for materials that contact food.

Carolina Sousa et al, Potential Transfer of Toxic Gluten from Biodegradable Tableware to Gluten-Free Foods: Implications for Individuals with Gluten-Related Disorders, Journal of Agricultural and Food Chemistry (2025). DOI: 10.1021/acs.jafc.5c07516

Study finds sports injuries sustained during a woman's period might be more severe
Injuries sustained by elite female football players during menstruation are more severe and result in over three times more days lost compared to injuries at other times in the menstrual cycle. While menstruation does not increase injury incidence, hormonal and physiological changes may worsen injury severity and prolong recovery. Individual menstrual tracking and tailored training may help reduce injury impact.

Menstruation and injury occurrence; a four season observational study in elite female football players, Frontiers in Sports and Active Living (2025). DOI: 10.3389/fspor.2025.1665482

Why some people live to 100 years or more? Because they carry a higher proportion of genetic material from Western Hunter-Gatherers!

Our hunter-gatherer ancestors have given us many things. They passed down mastery of fire for cooking and early survival technologies, such as stone tools. They may also have given us the secret to a long life. A new study published in the journal GeroScience found that Italian centenarians carry a higher proportion of genetic material from Western Hunter-Gatherers (WHG) compared to the general population.

It has been known for some time that longevity can be explained by "good" genes, as well as by other factors such as our environment and daily habits. Some studies have found individual genes linked to longer life, while others suggest that ancestral DNA may play a role.

Italy has one of the highest concentrations in the world of people living to 100 or more. To help understand why, researchers analyzed the genomes of 333 centenarians and 690 healthy adult controls aged around 50. They compared the DNA of these individuals with 103 ancient genomes of the four groups that make up the modern Italian gene pool.

These are Western Hunter-Gatherers, who were among the original inhabitants of Europe after the Ice Age, Anatolian Neolithic farmers, Bronze Age nomadic groups and ancient groups from the Iranian and Caucasus regions.
The results revealed that those who reached the age of 100 tended to have more Western Hunter-Gatherer DNA than the average person. "The present study shows for the first time that the Villabruna cluster/WHG lineage... contributes to longevity in the Italian population," wrote the research team.

Till now mediterranean diet stole most of the credit!

While everyone in the study carried a mix of DNA from all four ancient groups, only the WHG genetic material was linked to longevity.

In fact, for every small increase in hunter-gatherer DNA, a person's odds of becoming a centenarian rose by 38%. This was even more powerful in women, who were more than twice as likely to reach 100 if they had a higher proportion of this ancient DNA. 
Part 1

The team also has a theory as to how WHG genes may help people live to a ripe old age. They suggest that these variants were selected during the last Ice Age, when our ancestors had to survive extremely harsh conditions with limited food resources. The scientists think these genes helped improve metabolism to process food more efficiently and strengthen the immune system to protect the body from age-related stresses.

Stefania Sarno et al, Western Hunter-Gatherer genetic ancestry contributes to human longevity in the Italian population, GeroScience (2025). DOI: 10.1007/s11357-025-02043-4

Part 2

Grok spews misinformation about deadly Australia shooting
Grok, an AI chatbot, disseminated multiple false claims during the Bondi Beach mass shooting in Australia, including misidentifying a hero, mislabeling images, and suggesting a survivor staged his injuries. These errors highlight the limitations of AI chatbots in real-time fact-checking, especially during rapidly evolving news events, and underscore the continued need for human oversight.

Source: News agencies

HOW THE BRAIN MEASURES DISTANCE OF A FAMILIAR PLACE IN THE DARK

Whether you are heading to bed or toilet of your home in the dark, you don't need to turn on the lights to know where you are as you walk through your house at night. This hidden skill comes from a remarkable ability called path integration: your brain constantly tallies your steps and turns, allowing you to mentally track your position like a personal GPS. You're building a map by tracking movement, not sight.
Scientists think that understanding how the brain performs path integration could be a critical step toward understanding how our brain turns momentary experiences into memories of events that unfold over time.
In their study, the team trained mice to run a specific distance in a gray virtual reality environment without visual landmarks, in exchange for a reward. The animals could only judge how far they had traveled by monitoring their own movement, not by relying on environmental cues.

As mice performed this task, the scientists recorded tiny electrical pulses that neurons use to communicate, allowing them to observe the activity of thousands of neurons.

They focused on the activity of neurons in the hippocampus, a region essential for both navigation and memory. Using computer modeling, they then analyzed these signals to reveal the computational rules the brain uses for path integration.
The hippocampus is known to help animals find their way through the environment. In this brain region, some neurons become active at specific places. However, in environments full of sights, sounds, and smells, it is difficult to tell whether these neurons are responding to those sensory cues or to the animal's position itself.
The scientists discovered that during navigation without landmarks, most hippocampal neurons followed one of two opposite patterns of activity. These patterns were crucial for helping the animals keep track of how far they had traveled.

In one group of neurons, activity sharply increased when the animal started moving, as if marking the start of the distance-counting process. The activity of these neurons then gradually ramped down at different rates as the animal moved further, until reaching the set distance for a reward.

A second group of neurons showed the opposite pattern. Their activity dropped when the animal started moving, but gradually ramped up as the animal traveled farther.

The team discovered that these activity patterns act as a neural code for distance, with two distinct phases. The first phase (the rapid change in neural activity) marks the start of movement and the beginning of distance counting. The second phase (the gradual ramping changes in neural activity) counts the distance traveled. Both short and long distances could be tracked in the brain by using neurons with different ramping speeds.
The scientists have discovered that the brain encodes the elapsed distance or time needed to solve this task using neurons that show ramping activity patterns.
This is the first time distance has been shown to be encoded in a way that differs from the well-known place-based coding in the hippocampus. These findings expand our understanding that the hippocampus is using multiple strategies—ramping patterns in addition to the place-based coding—to encode elapsed time and distance."

When the researchers disrupted these patterns by manipulating the circuits that produce them, the animals had difficulty performing the task accurately and often searched for the reward in the wrong location.

Time or distance encoding by hippocampal neurons via heterogeneous ramping rates, Nature Communications (2025). DOI: 10.1038/s41467-025-67038-3

Chronic fatigue syndrome linked to widespread energy, immune and vascular changes
People with ME/CFS exhibit concurrent abnormalities in cellular energy metabolism, immune cell maturity, and plasma proteins linked to vascular dysfunction. Elevated AMP and ADP levels indicate impaired ATP production, while immune profiling shows less mature lymphocyte subsets. Machine learning identified seven biological markers strongly associated with ME/CFS.

Key findings of a multimodal study published in the journal Cell Reports Medicine include changes in markers of cellular energy metabolism, in the proportions and maturity of circulating immune cells, and in plasma proteins associated with blood vessel dysfunction in people with ME/CFS.

Led by researchers from Macquarie University, the study compared whole blood samples from 61 people meeting clinical diagnostic criteria for ME/CFS with samples from healthy age- and sex-matched volunteers.

Cellular and immune system changes
White blood cells from ME/CFS patients showed evidence of "energy stress" in the form of higher levels of adenosine monophosphate (AMP) and adenosine diphosphate (ADP), indicating reduced generation of adenosine triphosphate (ATP), the key energy source within cells.

Profiling of immune cell populations revealed a trend toward less mature subsets of T-lymphocyte subsets, dendritic cells and natural killer cells in people with ME/CFS.

Comprehensive analysis of plasma proteins highlighted disruptions of vascular and immune homeostasis in patients with ME/CFS. Levels of proteins associated with activation of the endothelium—the innermost lining of blood vessels—and remodeling of vessel walls were higher, while levels of circulating immunoglobulin-related proteins were lower.

Benjamin Heng et al, Mapping the complexity of ME/CFS: Evidence for abnormal energy metabolism, altered immune profile, and vascular dysfunction, Cell Reports Medicine (2025). DOI: 10.1016/j.xcrm.2025.102514

How embryos and the uterus 'talk' during implantation

Implantation is one of the most delicate and failure-prone stages of pregnancy in humans and other animals.

A new study shows that the embryo and the uterine lining conduct an active "conversation" from the very earliest stages of implantation. They engage in a back and forth of tiny packages called extracellular vesicles and lipid droplets, which carry metabolites and signals. Hormones determine what the uterus sends, and one signaling pathway (related to aryl hydrocarbon receptor, [AhR]) appears to assist in determining how hospitable the uterine environment is.

When this pathway is blocked, embryos attach more strongly. These packages are taken up quickly; their genetic material is used almost immediately, they influence how cells use energy and handle fats, and they reshape the uterine tissue—all in ways that support embryo attachment and implantation.

Published in The Journal of Extracellular Vesicles, the research uncovers a previously underappreciated communication network between the early embryo and the uterus, which may be critical for successful implantation and early pregnancy. The study reveals how extracellular vesicles, lipid droplets, and AhR ligands dynamically interact during the earliest stages of embryo-maternal crosstalk.

Alisa Komsky‐Elbaz et al, Extracellular Vesicles, Lipid Droplets and AhR Ligands in Early Implantation: The Dynamics of Embryo‐Maternal Crosstalk, Journal of Extracellular Vesicles (2025). DOI: 10.1002/jev2.70161

Sick, Immobile Young Ants Send “Kill Me” Signal to Colony Workers

Cocooned ants infected with a deadly fungus call on workers to kill them to protect the colony—the first example of altruistic disease signaling in social insects.

Adult ants that have been infected with deadly pathogens often leave the colony to die so as not to infect others. But, like infected cells in tissue, young ants are largely immobile and lack this option.

Invasive garden ant pupae that have been infected with a deadly fungal pathogen produced chemicals that induced worker ants to unpack their cocoons and kill them, preventing the disease from spreading to the rest of the colony.

In a new study, researchers discovered that the infected pupae only released chemicals when there were workers nearby, suggesting that the sick young ants put these events in motion. The researchers’ findings, published in Nature Communications, are the first evidence of altruistic disease signaling in a social insects and share similarities with how sick and dying cells send a “find me and eat me” signal to the immune system.

Infected pupae consistently upregulated immune genes upon infection, regardless of whether workers were around. However, changes in the level of specific CHCs only occurred when the pupae were infected and workers were nearby. Furthermore, the team found that when they coated healthy pupae with extracts from infected pupae, workers unpacked the healthy pupae more frequently than healthy pupae covered in “non-signal” extracts. Altogether, these observations indicate that infected pupae likely release specific CHCs so workers could find and kill them, which means that these young ants sacrifice themselves to benefit the colony.

1. Pull CD, et al. Destructive disinfection of infected brood prevents systemic diseas.... Elife. 2018;7:e32073.
2. Dawson EH, et al. Altruistic disease signalling in ant colonies. Nat Commun. 2025;16:10511.
3. Kugelberg E. Cell death: Find me and eat me. Nat Rev Immunol. 2016;16(3):131.