Fever chills explained: How brain signals push warmth-seeking to fight infection
When running a fever during infection, we often feel chills, which prompt us to take action to warm ourselves, such as turning on a heater or adding layers of clothing. Increased body temperature helps inhibit pathogen growth and boosts immune cell activity.
A recent rat study by researchers identified the neural mechanism underlying chills, a cold sensation that supports the body's response to infection. The findings were published in The Journal of Physiology.
When mammals are infected, their immune system produces a pyrogenic mediator, prostaglandin E₂ (PGE₂), in the brain's vascular cells. PGE₂ acts on the preoptic area, the brain's thermoregulatory center, and triggers autonomic fever responses, such as shivering, increased heat production in brown adipose tissue, and constriction of skin blood vessels.
PGE₂ is known to trigger not only autonomic fever responses but also behavioral fever responses including warming behaviors with chills.
The team hypothesized that PGE₂ acts on the lateral parabrachial nucleus (LPB) in the brain, which relays sensory signals, to trigger chills and warmth-seeking behaviors during infection. This was based on their 2023 study showing that LPB neurons transmit skin-temperature sensations to the forebrain and influence body temperature regulation. To test this hypothesis, the team conducted experiments on rats.
The researchers found that the rats' axons primarily target the central nucleus of the amygdala, which regulates emotions such as discomfort and fear, with minimal projections to the preoptic area.
The team also found that the pathway from EP3-expressing neurons to the amygdala is activated in cold environments and transmits cold sensations.
These findings suggest that during infection, PGE₂ boosts cold signals from the LPB to the central nucleus of the amygdala via EP3 receptors, triggering chills and promoting warmth-seeking behaviour.
This study demonstrates that PGE₂ increases body temperature by acting on two brain regions: the preoptic area, which drives autonomous thermogenic responses, and the lateral parabrachial nucleus (LPB), which mediates behavioural responses.
The pyrogenic mediator prostaglandin E2 elicits warmth seeking via EP3 receptor-expressing parabrachial neurons: a potential mechanism of chills, The Journal of Physiology (2026). DOI: 10.1113/JP289466
Only humans have chins and it's an evolutionary accident
Every chin is distinctive in the sense that humans are the only primates to possess that physical characteristic.
Chimpanzees, humans' closest living relatives, do not have a chin. Neither did Neanderthals, Denisovans, or any other extinct human species. Humans, it turns out, have a unique capacity to "take it on the chin" because we're uniquely in possession of that physical feature. That exclusive nature makes the chin well suited for identifying Homo sapiens in the fossil record.
The chin evolved largely by accident and not through direct selection, but as an evolutionary by-product resulting from direct selection on other parts of the skull.
The chin is a spandrel, a feature that arises as an unintended byproduct of evolution, just as the space under a staircase exists not for any architectural purpose, but as a byproduct of building a convenient way to get from one level to the next.
Just because we have a unique feature, like the chin, does not mean that it was shaped by natural selection to enhance an animal's survivability, for example, a buttress for the lower jaw to help dissipate the forces of chewing. The chin is likely a byproduct, not an adaptation.
Noreen von Cramon-Taubadel et al, Is the human chin a spandrel? Insights from an evolutionary analysis of ape craniomandibular form, PLOS One (2026). DOI: 10.1371/journal.pone.0340278
The origin of magic numbers: Why some atomic nuclei are unusually stable A new model explains the stability of magic nuclei by directly linking their shell structure to underlying proton–neutron interactions via nuclear wavefunctions. This approach naturally reproduces magic numbers and bridges phenomenological and first-principles nuclear models, offering insights into the strong nuclear force and the properties of heavy, exotic nuclei.
Space mining without heavy machines? Microbes harvest metals from meteorites aboard space station Microbes can extract valuable metals from meteorites in microgravity, with fungi notably enhancing palladium release. Microbial biomining remains effective in space, while nonbiological leaching is less efficient under microgravity. Extraction rates vary by metal, microbe, and gravity, highlighting the complexity and potential of microbial resource extraction for space and Earth applications.
Rosa Santomartino et al, Microbial biomining from asteroidal material onboard the international space station, npj Microgravity (2026). DOI: 10.1038/s41526-026-00567-3
Nanoplastics hindering cognitive abilities of fish, international research shows
Plastic makes up about 80 to 85% of marine litter, according to environmental research, with the most commonly used plastics breaking down into smaller pieces under ultraviolet light and low temperatures.
Nanoplastic exposure can impair the cognitive abilities of fish and could lead to significant impacts on marine species' ability to survive, according to a new international study. Exposure to nanoplastics impairs cognitive function in marine medaka (Oryzias melastigma), leading to increased errors and impulsive decision-making during behavioral tests. These changes may reduce survival by affecting foraging, predator avoidance, and reproduction. Nanoplastics, due to their small size, are highly bioavailable and pose a significant, underrecognized threat to marine ecosystems.
The important things for any animal are reproduction, shelter and feed. For a fish which has changed its behavior, it may have trouble capturing food and most importantly, have trouble avoiding predators.
It may also be affected when mating and finding a mate, let alone spawning. There are huge potential effects on those three basic requirements for survival.
Xianyu Yuan et al, Nanoplastic exposure damages neural plasticity, cognitive abilities, and ecological adaptability of marine medaka Oryzias melastigma, Marine Pollution Bulletin (2026). DOI: 10.1016/j.marpolbul.2026.119232
No association between mRNA COVID-19 vaccination during pregnancy and autism in children, new research shows Children born to mothers who received an mRNA COVID-19 vaccine during or shortly before pregnancy show no increased risk of autism or other neurodevelopmental problems at 18–30 months compared to children of unvaccinated mothers. Neurodevelopmental assessments revealed no significant differences between the groups, supporting the vaccine's safety in pregnancy.
Association between SARS-CoV-2 vaccine in pregnancy and child neurodevelopment at 18–30 months, Pregnancy (2026).
Failed supernova provides clearest view yet of a star collapsing into a black hole
Astronomers have watched a dying star fail to explode as a supernova, instead collapsing into a black hole. The remarkable sighting is the most complete observational record ever made of a star's transformation into a black hole, allowing astronomers to construct a comprehensive physical picture of the process.
Combining recent observations of the star with over a decade of archival data, the astronomers confirmed and refined theoretical models of how such massive stars turn into black holes. The team found that the star failed to explode as a supernova at the end of its life; instead, the star's core collapsed into a black hole, slowly expelling its turbulent outer layers in the process.
The discovery will help explain why some massive stars turn into black holes when they die, while others don't.
The now-deceased star, called M31-2014-DS1, is located around 2.5 million light-years away from Earth in the neighbouring Andromeda galaxy.
They found that M31-2014-DS1's infrared light began brightening in 2014. Then in 2016, the star swiftly dimmed far below its original luminosity in barely a year.
Observations in 2022 and 2023 showed that the star essentially vanished in visible and near-infrared light, becoming one ten-thousandth as bright in these wavelengths. Its remnant is now only detectable in mid-infrared light, where it shines at a mere one-tenth as bright as before.
Comparing these observations with theoretical predictions, the researchers concluded that the star's dramatic fading to such a small fraction of its original total brightness provides strong evidence that its core collapsed and became a black hole.
Stars fuse hydrogen into helium in their cores, and that process generates outward pressure to balance the incessant inward pull of gravity. When a massive star roughly 10 or more times heavier than our sun begins to run out of fuel, the balance between inward and outward forces is disrupted. Gravity begins to collapse the star, and its core succumbs first to form a dense neutron star at the center.
Often, the emission of neutrinos in this process generates a powerful shock wave that is explosive enough to rip apart most of the core and outer layers in a supernova. However, if the neutrino-powered shock wave fails to push the stellar material out, theory has long suggested that most of the stellar material would instead fall back into the neutron star, forming a black hole.
The observations and analysis of M31-2014-DS1 enabled the team to reinterpret observations of a similar star, NGC 6946-BH1. This led to an important breakthrough in understanding what had happened to the outer layers that had enveloped the star after it failed to go supernova and collapsed into a black hole. The overlooked element? Convection.
Convection is a byproduct of the vast temperature differences inside the star. Material near the star's center is extremely hot, while the outer regions are much cooler. This differential causes gases within the star to move from hotter to cooler regions.
When the star's core collapses, the gas in its outer layers is still moving rapidly due to this convection. Theoretical models developed by astronomers at the Flatiron Institute have shown that this prevents most of the outer layers from falling directly in; instead, the innermost layers orbit outside of the black hole and drive the ejection of the outermost layers of the convective region.
The ejected material cools as it moves farther from the hot material around the black hole. This cool material readily forms dust as atoms and molecules combine. The dust obscures the hot gas orbiting the black hole, warming the dust and producing an observable brightening in infrared wavelengths. This lingering red glow is visible for decades after the star itself disappears.
Why visceral fat triggers diabetes: Study points to loss of protective macrophages
Scientists discovered a surprising new way the body can fight insulin resistance and diabetes—by boosting a special type of "good" immune cell in fat tissue.
Reported in Nature Communications, the preclinical findings pave the path to developing a medication to treat and prevent type 2 diabetes, potentially replacing or supplementing GLP-1 weight maintenance drugs that lose effectiveness over time.
One-third of our population is obese or overweight—over the next decade or so, obesity will drive increasing rates of many chronic diseases, including diabetes.
Inflammation driven by immune signals given off by excess fat surrounding abdominal organs has long been known to trigger the insulin resistance that leads to type 2 diabetes.
The researchers found is that there is a subset of immune cells in our fat tissue that are actually helpful. Although they're immune cells, they're not inflammatory—rather, they actually suppress the inflammation that causes insulin resistance.
This subset of immune cells—called resident macrophages—clean up dead cells, fight infections and keep tissues healthy. SerpinB2 is a protein that helps resident macrophages survive. When too much visceral fat accumulates—which occurs when someone is overweight or obese—inflammation increases and SerpinB2 levels plummet.
This causes resident macrophages to die out, which allows fat tissue to grow larger and become more inflamed. Ultimately, the body can't respond as well to insulin, which controls blood sugar, and the person develops diabetes.
When overweight mice with insulin-resistance were given antioxidant supplements, their levels of resident macrophages increased and their insulin sensitivity improved.
Tissue-resident macrophage survival depends on mitochondrial function regulated by SerpinB2 in chronic inflammation, Nature Communications (2026). DOI: 10.1038/s41467-026-69196-4
Light-based sensor detects early molecular signs of cancer in the blood
Researchers have developed a highly sensitive light-based sensor that can detect extremely low concentrations of cancer biomarkers in the blood. The new technology could one day make it possible to spot early signs of cancer and other conditions using a simple blood test.
Biomarkers such as proteins, DNA or other molecules can be used to reveal the presence, progression or risk of cancer and other diseases. However, one of the main challenges in early disease diagnosis is the extremely low concentration of biomarkers present at the onset.
The new sensor developed now combines nanostructures made of DNA with quantum dots and CRISPR gene editing technology to detect faint biomarker signals using a light-based approach known as second harmonic generation (SHG).
This approach could help make disease treatments simpler, potentially improve survival rates and lower overall health care costs.
Wenbo Du et al, Sub-Attomolar-Level Biosensing of Cancer Biomarkers Using SHG Modulation in DNA-Programmable Quantum Dots/MoS2 Disordered Metasurfaces, Optica (2026). DOI: 10.1364/optica.577416
Plants retain a 'genetic memory' of past population crashes, study shows
Plant populations that have experienced past crashes due to human activity retain reduced genetic diversity and increased inbreeding, even after apparent recovery. These genetic effects persist for many generations and are not reflected by current population size alone, highlighting the importance of considering genetic history in conservation planning to ensure long-term resilience.
Researchers have found that plants living in areas where human activity has caused population crashes carry long-lasting genetic traces of that history, such as reduced genetic diversity. Because genetic diversity helps species adapt to climate change, disease, and other stresses, the study suggests it is vital to consider a population's history-influenced genetics alongside its size and habitat in conservation planning.
Two populations may look equally healthy on the surface, yet one may be far more vulnerable to future environmental change because it lacks genetic diversity and consists of individuals with poorly mixed genetic material. This can impede evolutionary responses to changing conditions.
Daniel J. Schoen et al, Population genomic signatures of founding events in autonomously self‐fertilizing plants: a test with Impatiens capensis, New Phytologist (2026). DOI: 10.1111/nph.70880
Cholesterol crystals may trigger some liver disease Cholesterol crystals in the liver can increase tissue stiffness early in metabolic dysfunction-associated steatotic liver disease (MASLD), preceding fibrosis. This process may contribute to disease progression and could help identify individuals at higher risk for severe liver damage. Non-invasive detection methods and cholesterol-lowering treatments may offer new avenues for early intervention.
David Li et al, Cholesterol-containing lipid crystals can directly stiffen the rat steatotic liver before fibrosis, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2518060123
Scientists discover new gatekeeper cell in the brain A previously unidentified population of base barrier cells has been found at the base of the choroid plexus, forming a tight junction-based barrier that compartmentalizes the brain, choroid plexus, and cerebrospinal fluid. This barrier restricts molecular movement under healthy conditions but becomes vulnerable during systemic inflammation, potentially allowing harmful substances into the brain. These cells are present in both mice and humans.
Daan Verhaege et al, Base barrier cells provide compartmentalization of choroid plexus, brain and CSF, Nature Neuroscience (2026). DOI: 10.1038/s41593-025-02188-7
Traffic noise linked to higher cholesterol and lipid levels in blood Long-term exposure to nighttime road traffic noise above 50–55 dB is associated with higher blood levels of total cholesterol, LDL cholesterol, and other lipid-related metabolites, which are established risk factors for cardiometabolic diseases. These metabolic changes show a clear exposure-response pattern, suggesting that reducing nighttime noise could benefit public health.
Yiyan He et al, Metabolic profiles of nighttime road traffic noise exposure: A multi-cohort study in the European LongITools project, Environmental Research (2026). DOI: 10.1016/j.envres.2026.123887
AI is distorting online research, from polls to public policy AI systems can now convincingly simulate human responses in online surveys and polls, undermining the reliability of survey-based research and public policy data. Traditional safeguards like CAPTCHAs and attention checks are increasingly ineffective. New strategies, including behavioural analysis and tasks exploiting human error patterns, are needed to maintain data integrity as AI advances.
Folco Panizza et al, How to deal with the survey-taking AI agents that threaten to upend social science, Nature (2026). DOI: 10.1038/d41586-026-00386-2
Fungi flip mattresses into useful materials Material from discarded mattresses can be upcycled into fire-resistant insulation with the help of a fungus. Researchers mixed polyurethane foam from mattresses into a nutrient-rich liquid and added spores of the fungus Penicillium chrysogenum. The fungus produced deposits of calcium carbonate as it grew, which meshed with the foam to form a lightweight material that could withstand temperatures up to around 1000 °C. Through natural biological processes, we can give this waste a second life.
Intelligence or interest creation? Whatever it is, if it runs in the families, you can have pics like this.
On the left is the legendary physicist Niels Bohr,who received the Nobel Prize in 1922 for his groundbreaking research on the electron shell and quantized energy level.
Right next to him, Aage Niels Bohr (he was drawing numbers on the board ) who later won the Nobel Prize in Physics in 1975.
Aage Bohr and his father, Niels, are one of the few father-son pairs to both receive Nobel Prizes in Physics, separated by 53 years.
From 1946, father and son were simultaneously doing research at the Niels Bohr Institute.
The little child in the picture who is quietly coming forward and calculating with his grandfather and father is Thomas Bohr, another legendary physicist of this family.
He is a professor at the Technical University of Denmark and his research on macroscopic fluid dynamic systems is well known.
Organic molecule stores solar energy for years, then releases it as heat on demand
When the sun goes down, solar panels stop working. This is the fundamental hurdle of renewable energy: how to save the sun's power for a rainy day—or a cold night. Chemists have developed a solution that doesn't require bulky batteries or electrical grids. In a paper published in the journal Science, they detail a new material that captures sunlight, stores it within chemical bonds and releases it as heat on demand.
The material, a modified organic molecule called pyrimidone, is the latest advancement in molecular solar thermal (MOST) energy storage.
To create this molecule, the team looked to a surprising source: DNA. The pyrimidone structure is similar to a component found in DNA that, when exposed to UV light, can undergo reversible structural changes.
By engineering a synthetic version of this structure, the team created a molecule that stores and releases energy reversibly.
Traditional solar panels convert light into electricity; however, most systems convert light into chemical energy. The molecule acts like a mechanical spring: when hit with sunlight, it twists into a strained, high-energy shape. It stays locked in that shape until a trigger—such as a small amount of heat or a catalyst—snaps it back to its relaxed state, releasing the stored energy as heat.
The team's new molecule is a heavy hitter. It boasts an energy density of more than 1.6 megajoules per kilogram. That is roughly double the energy density of a standard lithium-ion battery—which comes in at around 0.9 MJ/kg—and significantly higher than previous generations of optical switches.
Han P. Q. Nguyen et al, Molecular solar thermal energy storage in Dewar pyrimidone beyond 1.6 MJ/kg, Science (2026). DOI: 10.1126/science.aec6413
Why you hardly notice your blind spot: New tests pit three theories of consciousness
Although humans' visual perception of the world appears complete, our eyes contain a visual blind spot where the optic nerve connects to the retina. Scientists are still uncertain whether the brain fully compensates for the blind spot or if it causes perceptual distortions in spatial experience. A new study protocol, published in PLOS One, seeks to compare different theoretical predictions on how we perceive space from three leading theories of consciousness using carefully controlled experiments.
Predictions from three theories of consciousness
The new protocol focuses on three contrasting theories of consciousness: Integrated Information Theory (IIT), Predictive Processing Active Inference (AI), and Predictive Processing Neurorepresentationalism (NREP). Each of the theories have different predictions about the effects that the blind spot's structural features have on the conscious perception of space, compared to non-blind spot regions.
IIT argues that the quality of spatial consciousness is determined by the composition of a cause-effect structure, and that the perception of space involving the blind spot is altered. On the other hand, AI and NREP argue that perception relies on internal models that reduce prediction errors and that these models adapt to accommodate for the structural deviations resulting from the blind spot. Essentially, this means that perceptual distortions should either appear small or nonexistent in both theories. However, AI and NREP differ in some ways.
"Specifically, NREP posits that lesions of portions of the visual field can have an effect on spatial estimates, but will be largely compensated for by the sensory evidence available from intact portions of the visual field.
According to AI, the quality of spatial experience is determined by the cause-effect structure under a generative model apt for active vision. This model of projective geometry is not the geometry of anatomical projections. Thus, AI proposes that perceptual judgments should not be altered when involving the blind spot, other than possible changes in perceptual uncertainty, due to differences in sensory sampling," the protocol authors explain.
To test out the three theories, the researchers put together a series of three psychophysical tasks, which include distance estimation, area size matching, and motion curvature judgment, all near or away from the blind spot. The tasks use colored glasses for dichoptic presentation, which allows for stimuli to be shown to one eye at a time. The study also utilizes eye tracking to ensure accurate fixation and to prevent unintentional stimulation of the blind spot. The research team also conducted analysis with simulated data of IIT, NREP and AI predictions for their distance estimation task, area size task and motion curvature task. The simulated data showed that IIT predicts spatial warping near the blind spot, while AI and NREP predict little or no distortion, with possible small decreases in precision.
As with most studies, there are potential limitations in interpreting the data when the actual experiments take place. For example, the theories in question predict the direction but not the magnitude of effects, making interpretation challenging.
The team also notes that unexpected results, such as an object appearing larger when it is predicted to appear smaller, may not be easily explained by any theory. Still, studies using the protocol have the potential to address some fundamental questions about how we perceive a seamless world with gaps in sensory input and may even advance the understanding of consciousness.
Clement Abbatecola et al, Protocol for investigating the warping of spatial experience across the blind spot to contrast predictions of the Integrated Information Theory and Predictive Processing accounts of consciousness, PLOS One (2026). DOI: 10.1371/journal.pone.0340593
The discovery of a tiny RNA molecule and clues to origin of life
One of the greatest mysteries of our planet is how a soup of lifeless chemicals transformed into the first living cell. There are several competing theories about where this happened, from frozen polar ice to superheated hydrothermal vents. But one thing that most scientists agree on is that life could not begin until a molecule appeared that could spontaneously copy itself.
For decades, the RNA World hypothesis has proposed that RNA was that molecule and that it proliferated before the evolution of DNA and proteins. This RNA had to be able to store genetic information and also build things such as new RNA strands.
However, there is a major problem with this school of thought: the RNA molecules (ribozymes) that we know can copy other RNA molecules are large and complex. That means it is highly unlikely they would have formed spontaneously in the primordial soup.
But a new candidate has emerged that might solve this puzzle. In a study published in the journal Science, researchers report the discovery of a small RNA molecule called QT45.
They found it after searching through a vast library of 12 trillion random RNA sequences. They were looking for any snippets of RNA that could act as a polymerase—a molecular builder. When the team found a few promising candidates, they put them through a molecular version of the survival-of-the-fittest test. They challenged them to build longer and longer chains under increasingly tougher conditions. QT45 emerged as the winner.
The scientists then ran experiments in a slushy, salty mixture of ice crystals and liquid to mimic conditions of early Earth. In this lab setting, QT45, which comprises just 45 nucleotides, proved it could act as a polymerase. It built a complementary RNA strand and then used that as a template to create a brand-new copy.
The study shows that the complex functions needed for RNA replication... can all be performed by an RNA motif of just 45 nucleotides.
According to the study authors, if a molecule this tiny is capable of performing complex tasks like building new strands and copying itself, life-starting molecules are likely to be more common.
Edoardo Gianni et al, A small polymerase ribozyme that can synthesize itself and its complementary strand, Science (2026). DOI: 10.1126/science.adt2760
Why phage contamination is hard to kill, and how charged nanoparticles could help
Bacteriophages are viruses that can kill bacteria through highly specific interactions. While this property can be beneficial in selected applications, bacteriophages represent a serious threat to laboratories and industries that rely on bacterial cultures for production. Their selective inactivation remains a major challenge. Recently, researchers demonstrated an innovative solution that enables targeting the surface of bacteriophage through electrostatic interactions as a promising strategy for their inactivation without adversely affecting bacterial strains or eukaryotic cells. Decades ago, antibiotics were considered wonder drugs capable of curing bacterial infections. Unfortunately, overuse of these drugs led to the development of antibiotic-resistance in many pathogenic bacterial strains, raising global concern. One of the solutions to defeat these pathogens is bacteriophages, also called phages. While phages are explored as therapeutic agents in medicine, their presence is highly undesirable in laboratories and industrial processes that depend on carefully controlled bacterial cultures.
In many industrial sectors, including food fermentation, enzyme, pharmaceuticals, and cosmetics production, specific bacterial strains are essential for efficient and reproducible manufacturing. In these settings, bacteriophages pose a major risk, as they can selectively infect and eliminate production strains, leading to failed batches and significant economic losses. Phages may also appear in agriculture or wastewater treatment environments, where their presence can influence microbial populations, but in controlled bioprocesses their uncontrolled spread is particularly detrimental.
Despite their small size, bacteriophages are highly persistent and can easily spread within laboratory and industrial environments. They may be introduced through contaminated raw materials, inadequately disinfected equipment, surfaces, or even air. Once present, phages can rapidly propagate within bacterial cultures, often remaining undetected until the entire system collapses due to bacterial lysis.
To prevent phage contamination, laboratories and factories rely on strict hygiene protocols involving sterilization and disinfection methods such as UV-C radiation, high temperature and pressure, ozone, and aggressive chemicals including potassium peroxymonosulfate (Virkon), ethanol, bleach, and hydrogen peroxide. These approaches typically aim to damage phage capsid proteins or nucleic acids, thereby inactivating the virus.
However, bacteriophages can aggregate, increasing their resistance to harsh environmental conditions such as heat or chemical exposure. Moreover, phages are often more resilient than bacteria themselves. As a result, disinfection methods strong enough to eliminate phages frequently destroy the bacterial strains required for industrial processes. This lack of selectivity represents a critical limitation of existing anti-phage strategies and drives the search for safer, more effective solutions. Part 1
Bacteriophage contamination is difficult to eliminate due to phages’ persistence and resistance to standard disinfection, which often harms beneficial bacteria. Charged polypyrrole nanoparticles with 1% carboxyl groups selectively inactivate phages via electrostatic interactions, sparing bacteria and eukaryotic cells, and show low cytotoxicity, offering a scalable, targeted solution for bioprocess protection.
Addressing these challenges, the interdisciplinary team of researchers propose a solution that enables the selective killing of phages without any harmful effect on bacteria. Their latest work, published in Materials & Design, shows an innovative approach based on polymeric nanospheres having a well-defined surface that interacts with bacteriophages. Bacteriophages possess characteristic surface charges that differ from those of bacterial and eukaryotic cells. The researchers designed polypyrrole nanoparticles (NPs) that interact directly with charges on the phage surface through electrostatic interactions. Because the biological membranes of bacteria and human cells have different surface properties than bacteriophages, they are not affected, and the charged polypyrrole NPs act selectively on phages.
Importantly, the present study demonstrates that selective antiphage activity can be achieved using polymer-based nanoparticles, offering a significantly cheaper and scalable alternative to other nanostructural solutions like gold-based systems. The proposed nanoparticles are approximately 50 nm in diameter and contain specific chemical groups on their surface, namely negatively charged carboxylic groups, which enhance electrostatic interactions with bacteriophages. The researchers controlled the density of these groups during fabrication by polymerizing mixtures of pyrrole with and without carboxylic modifications.
Importantly, they identified an optimal surface composition required for effective phage inactivation. The cytotoxicity studies that were performed on fibroblasts demonstrated that the nanoparticles were biocompatible at concentrations effective for phage inactivation. The irreversible inactivation of phages along with minor cytotoxicity shows the potential of the proposed NP in biotechnology, antimicrobial, and medical applications.
Sada Raza et al, Targeted inactivation of bacteriophages by polypyrrole nanoparticles, Materials & Design (2025). DOI: 10.1016/j.matdes.2025.115204
Polluting the environment for all eternity—and still sticking our heads in the sand Plastic pollution persists in the environment, breaking down into microplastics and releasing PFAS and heavy metals at levels exceeding safety thresholds in small freshwater ecosystems. These contaminants threaten wildlife and human health. Despite global and national targets, current cleanup efforts and funding are insufficient, and long-term, coordinated action is urgently needed.
Hilde Ervik et al, Organic contaminants and toxic elements in marine plastic debris, water and sediments in small freshwater lakes in a Norwegian coastal archipelago, Heliyon (2026). DOI: 10.1016/j.heliyon.2025.e44232
Scientists decipher how two bacterial species cooperate to avoid being eaten Pseudomonas and Paenibacillus bacteria cooperate to evade amoeba predation by modifying the lipopeptide syringafactin. Pseudomonas produces syringafactin, which Paenibacillus activates via DL peptidases, converting it into an amoeba-toxic compound. This mechanism highlights a specific enzymatic cleavage of D/L-configured lipopeptides, aiding future natural product analysis and anti-infective development.
Shuaibing Zhang et al, Microbial DL-Peptidases Enable Predator Defense and Facilitate Structure Elucidation of Complex Natural Products, Journal of the American Chemical Society (2026). DOI: 10.1021/jacs.5c17955
How did humans develop sharp vision? Lab-grown retinas show likely answer Sharp human vision develops in early fetal life through the combined action of retinoic acid, which limits blue cone formation, and thyroid hormones, which convert blue cones into red and green cones in the foveola. This process establishes the unique cone distribution essential for high-acuity vision and may inform future therapies for retinal diseases.
Katarzyna A. Hussey et al, A cell fate specification and transition mechanism for human foveolar cone subtype patterning, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2510799123
Science academies failing to put women at the top Women now comprise about 19% of science academy members, up from 12% in 2015, but leadership roles remain largely male-dominated, with only one in five academies chaired by a woman and nearly half lacking women as vice-presidents or co-chairs. Women are 2.5 times more likely than men to report discrimination or harassment, and institutional mechanisms to address misconduct are often viewed as inadequate.
National science organizations may have more women members today than a decade ago, but representation at the highest level has failed to keep pace, according to analysis published on International Day of Women and Girls in Science.
The International Science Council (ISC), InterAcademy Partnership (IAP) and Standing Committee for Gender Equality in Science (SCGES) looked at data from 136 scientific organizations and surveyed nearly 600 scientists to get a picture of gender equality across science academies and unions worldwide.
They found that women made up around 19% of science academy members in 2025–up from 12% in 2015. But only one in five academies was chaired by a woman and almost half had no women as vice-presidents or co-chairs, representing a "very limited increase" in the last decade and no progress in the last five years, according to theirreport.
Science academies play a role in shaping research agendas and standards across different disciplines and advising policymakers.
On paper, most science organizations promote themselves as open and inclusive, with election procedures based on academic merit. But informal networks persist that determine who is put forward for leadership roles, the report suggests.
Additionally, women are 2.5 times more likely than men to report experiences of discrimination or harassment within scientific organizations and show less confidence in organizational mechanisms to address misconduct, it says.
Carolina Espinosa Luna et al, Economías de legitimidad abusiva: explicación sociológica de la violencia académica contra mujeres,Estudios Sociológicos de El Colegio de México(2026).DOI: 10.24201/es.2026v44.e2873
How Asian Elephants Decide You’re Worth Talking To
Body and face orientation both matter when elephants decide it’s worth communicating.
Elephants are often celebrated for their intelligence and emotional depth, but how much do they actually understand about us?
A study conducted at the Golden Triangle Asian Elephant Foundation in Chiang Rai, Thailand, suggests that Asian elephants (Elephas maximus) are highly perceptive of human attention, as they read visual cues that signal whether communication is even worth attempting.
Ten captive female Asian elephants were observed as an experimenter stood before them in four different orientations: facing them fully, turning away entirely, or showing only body or only face.
When both the experimenter's body and face were oriented toward them, the elephants gestured the most frequently. Body orientation emerged as a stronger cue than facial direction, but only when paired with eye contact. Neither signal alone was enough to significantly prompt communication.
So if you ever have the opportunity to interact with an elephant, make sure you pay full attention with your body language.
Antifungals are ‘ampho-terrible’ no more Scientists have identified a molecule that acts as a plug to clog proteins that are critical for the toxicity of the dangerous fungus Cryptococcus. The notoriously drug-resistant fungus causes symptoms similar to pneumonia and is particularly dangerous for people with compromised immune systems. Currently, the go-to drug class is amphotericin, deemed “ampho-terrible” by biochemist Gerry Wright. “Fungal cells are a lot like human cells, so the drugs that hurt them tend to hurt us too,” he says. “That’s why there are so few options available to patients.” After a decade of research, researchers discovered butyrolactol A, which acts as an adjuvant to make Cryptococcus more susceptible to other drugs.
Discovery could lead to new treatments for drug-resistant fungal infections
Fungal infections kill millions of people each year, and modern medicine is struggling to keep up. But researchers have identified a molecule that may help turn the tide — butyrolactol A, a chemical compound that targets a deadly, disease-causing fungi called Cryptococcus neoformans.
Infections caused by Cryptococcus are extremely dangerous. The pathogen, which can cause pneuomia-like symptoms, is notoriously drug-resistant, and it often preys on people with weakened immune systems, like cancer patients or those living with HIV. And the same can be said about other fungal pathogens, like Candida auris or Aspergillus fumigatus — both of which, like Cryptococcus, have been declared priority pathogens by the World Health Organization. Despite the threat, though, doctors have only three treatment options for fungal infections
The gold standard is a drug class called amphotericin - that is often called “amphoterrible,” because of the major toxic side-effects that it has on humans.
“Fungal cells are a lot like human cells, so the drugs that hurt them tend to hurt us too. That’s why there are so few options available to patients.”
The other two antifungal drug classes that are available — azoles and echinocandins — are much less effective treatment options, especially against Cryptococcus.
So, with a stagnant antifungal drug pipeline, a limited arsenal of approved medicines, and rising rates of drug resistance, scientists are now betting on something called “adjuvants” as a solution to the growing health threat.
Adjuvants are helper molecules that don’t actually kill pathogens like drugs do, but instead make them extremely susceptible to existing medicine.
The researchers found butyrolactol A, a known-but-previously-understudied molecule produced by certain Streptomyces bacteria. The researchers found that the molecule could synergize with echinocandin drugs to kill fungi that the drugs alone could not.
A common biomarker of schizophrenia and bipolar disorder revealed
For decades, schizophrenia and bipolar disorder (BD) were treated as distinct and unrelated psychiatric disorders. Schizophrenia is a psychiatric disorder characterized by altered thinking and emotional patterns, hallucinations, false or irrational beliefs (i.e., delusions), cognitive deficits, and disorganized speech. BD, on the other hand, is marked by extreme mood swings, ranging between periods of high-energy (i.e., mania or hypomania) and depressive episodes.
While the symptoms of schizophrenia and BD are markedly different, many patients diagnosed with either of these conditions experience psychosis at least once in their lifetime. Psychosis is a mental state that causes people to lose touch with reality, experiencing hallucinations, delusions, disorganized speech, and irrational thinking patterns.
More recently, studies found that patients diagnosed with schizophrenia and BD sometimes share other overlapping symptoms, as well as common patterns in their genes and brain organization. This inspired the idea that these disorders are part of a shared psychosis spectrum, which would explain their common features and characteristics.
Researchers reviewed and analyzed the findings of previous studies to further test this hypothesis and validate the existence of a psychosis spectrum of disorders. Their paper, published inNature Mental Health, outlines common brain features in patients with schizophrenia and BD, particularly differences in the integrity of white matter.
As part of their study, the researchers systematically reviewed brain imaging data collected by different teams of neuroscience and mental health researchers over the past 30 years. All this data was collected using magnetic resonance imaging (MRI), a non-invasive imaging technique that allows scientists to obtain 3D images of the brain and infer properties of white matter connections.
The researchers collectively analyzed the results of several studies, looking at schizophrenia and BD both individually and together, all while also accounting for differences in age and sex. This allowed them to identify brain regions that appear to be similarly affected in patients with either of the two disorders.
Most notably, they observed shared white matter alterationsin a region called the corpus callosum. This is a brain structure that connects the brain's left and right hemispheres.
This alteration was observed across the entire psychosis spectrum, rather than being limited to a single diagnosis.
Importantly, these findings remained significant (and in some cases became clearer) after accounting for age and sex, suggesting they are unlikely to be explained simply by illness duration or aging. This supports the idea that disruptions in brain connectivity may represent a core biological feature of psychosis.
The results of this recent meta-analysis pinpoint a candidate biomarker that appears to characterize both schizophrenia and BD.
Giuseppe Pierpaolo Merola et al, A systematic review and meta-analysis of transdiagnostic impairments in white matter integrity across the psychosis continuum, Nature Mental Health (2026). DOI: 10.1038/s44220-025-00573-6.
Why AI may overcomplicate answers: Humans and LLMs show 'addition bias,' often choosing extra steps over subtraction When making decisions and judgments, humans can fall into common "traps," known as cognitive biases. A cognitive bias is essentially the tendency to process information in a specific way or follow a systematic pattern. One widely documented cognitive bias is the so-called addition bias, the tendency of people to prefer solving problems by adding elements as opposed to removing them, even if subtraction would be simpler and more efficient. One example of this is adding more paragraphs or explanations to improve an essay or report, even if removing unnecessary sections would be more effective.
Researchers recently carried out a study aimed at investigating whether artificial intelligence (AI) agents, particularly the computational models underpinning the functioning of ChatGPT, also exhibit this tendency when answering user queries. Their findings, published in Communications Psychology, suggest that these models can inherit the addition bias from human-written texts that they are trained on.
Generative artificial intelligences, particularly large language models (LLMs), increasingly influence human decision-making, making it essential to understand how cognitive biases are reproduced or amplified in these systems
Building on evidence of the human 'addition bias'—a preference for additive over subtractive problem-solving strategies—this research compared humans with GPT-4 and GPT-4o in spatial and linguistic tasks.
Researchers carried out two studies that compared the responses of human participants to two distinct LLMs, namely GPT-4 and GPT-4o, respectively. The human participants and LLMs were tested on two different types of tasks: spatial and linguistic tasks. Spatial tasks entail the arrangement of shapes or structures in specific ways, while linguistic tasks require respondents to choose or generate specific texts following a set of instructions. They found that both the human participants and the LLMs they examined exhibited an addition bias. However, this bias was less pronounced in humans and more pronounced in LLMs on tasks where subtracting information was clearly the more efficient strategy to tackle a problem. Humans made fewer additive choices when subtraction was more efficient than addition (compared to when both were equally efficient), whereas GPT-4's output showed the opposite pattern.
Lydia Uhler et al, Influence of solution efficiency and valence of instruction on additive and subtractive solution strategies in humans, GPT-4, and GPT-4o, Communications Psychology (2026). DOI: 10.1038/s44271-026-00403-0.
Some glaciers can suddenly surge forward—with dangerous consequences
A small fraction of glaciers undergo sudden surges, advancing rapidly for months or years due to meltwater accumulation beneath the ice, which reduces friction. These surges, affecting about 1% of glaciers but 16% of global glacier area, can accelerate ice loss and create hazards such as floods and infrastructure damage. Climate change is altering surge frequency and unpredictability worldwide.
India is developing a large-scale "data city" in Visakhapatnam to accelerate its AI infrastructure, supported by major investments exceeding $175 billion, including projects from Google and other global firms. The initiative aims to establish a comprehensive AI ecosystem, targeting six gigawatts of data center capacity, and leverages strategic incentives and infrastructure to attract technology companies.
Creatures that can change from one form to another ?
Yes, Nature, too, has its shapeshifters, such as dimorphic fungi. While scientists have known for some time that they can reversibly transition between yeast and mycelium forms, a paper recently published in the journal Nature Communications explains how.
Some fungi, such as members of the Mucorales order, can live as yeasts, tiny single-celled organisms, or as mycelium, multicellular branching filaments. Triggers for the morphological switch include oxygen levels and glucose concentrations. How can a single genome encode two different body plans and could switch between them?
To find out, scientists grew the fungus (Mucor lusitanicus) under oxygen-rich conditions to promote mycelial growth, and under low-oxygen, high-carbon-dioxide conditions to induce the yeast form. Once the fungus had changed shape, the team collected samples and examined the active genetic instructions, specifically the RNA, to see which were being used in each form.
The team found that instead of using the same genes for both forms, the fungus uses paralogs. These are closely related genes that share a common ancestor and arise when a gene is duplicated within a single genome.
In total, they found 490 dimorphic gene families. Although each twin pair has similar functions, there is a specific version for yeast and one for mycelium. For example, a gene responsible for iron absorption in the yeast form has a nearly identical counterpart that performs the same function in the mycelium form.
They are organized in a very elegant way in the genome. The scientists discovered that two related genes are positioned back to back on the DNA and share a bidirectional promoter. These regulate gene expression and so act like control switches. It means the promoters can easily turn one off and the other on without getting them mixed up.
At the heart of the operation, according to the researchers, are two master regulator genes, dkl and dfl. When the team deleted them, the fungus could no longer control its switches and lost its ability to change shape.
The findings identify an evolutionary mechanism that integrates and optimizes the genetic information required for two distinct life forms within a single organism.
One of the most exciting aspects of this research is the potential for new antifungal treatments. Knowing how a fungus switches to its invasive mycelial form gives scientists a clear target to stop the transformation and therefore the spread of fungal infections.
Ghizlane Tahiri et al, Coordinated gene family evolution shapes the genome of dimorphic Mucorales, Nature Communications (2026). DOI: 10.1038/s41467-026-68866-7
Deer inhibit trees but raise plant diversity, 18-year study reveals
At high densities, white-tailed deer inhibit growth of trees but increase the overall diversity of smaller plant and weed species, according to a long-term study published recently. High densities of white-tailed deer suppress tree regeneration and reduce tree presence in both above-ground vegetation and the soil seedbank, limiting natural forest regrowth. However, deer browsing increases the diversity and evenness of smaller plant and weed species by preventing dominance by a few species. Active management is likely required for successful reforestation in areas with abundant deer.
A. Sophie Westbrook et al, Deer impact seedbanks and plant communities over 18 years of post-agricultural succession, PLOS One (2025). DOI: 10.1371/journal.pone.0339466
Deep-sea fish larvae rewrite the rules of how eyes can be built
Deep-sea fish larvae possess unique hybrid photoreceptor cells that combine structural features of rods with the molecular machinery of cones, enabling enhanced vision in the dim twilight zone. Unlike the typical vertebrate pattern where cones precede rods, these larvae use rod-like cones early in development, with some species retaining them into adulthood. This challenges established models of vertebrate retinal development.
Injured seabird desperately pecks at hospital door for help
An injured seabird sought help by pecking at the door of an emergency room at a hospital in Germany until medical staff noticed it and called firefighters to help with its rescue.
The cormorant, a shiny black waterbird, had a triple fishing hook stuck in its beak when it made its presence known at the glass door of the Klinikum Links der Weser hospital in the northern city of Bremen on Sunday.
In a joint effort, medical staff and firefighters removed the fishhook and treated the wound, the Bremen firefighter department said in a statement. The bird was later released back into nature on the grounds of the hospital park.
"When an injured cormorant does approach humans, it is usually an animal in extreme distress that has lost its natural shyness," the statement said.
A cormorant is a large bird with a long neck, wedge-shaped head and a distinctive sharp beak with a hooked tip. A fishhook in the bird's beak would be extremely dangerous for the animal. Infections, pain and even starvation are possible, the firefighter department said.
Want a tall, smart child? How IVF tests are selling a dream
Genetic tests marketed to IVF parents claim to predict traits like height and intelligence using polygenic risk scores, but these predictions are highly uncertain and offer minimal benefit—typically only a few IQ points or centimeters in height. Environmental and lifestyle factors play a much larger role in child development, and using such tests poses ethical, psychological, and medical risks without proven advantages.
Yes, men have a biological clock too. But it's not just age that affects male fertility
Male fertility declines with age, with sperm count, motility, morphology, and semen volume decreasing from the early 20s, and genetic damage in sperm increasing, raising miscarriage and birth defect risks. Environmental and lifestyle factors, such as oxidative stress, toxins, smoking, obesity, and certain medical conditions, also impact male fertility. New guidelines recommend simultaneous fertility assessment for both partners.
Bacterial strain from 5,000-year-old cave ice shows resistance against 10 modern antibiotics
Bacteria have evolved to adapt to all of Earth's most extreme conditions, from scorching heat to temperatures well below zero. Ice caves are just one of the environments hosting a variety of microorganisms that represent a source of genetic diversity that has not yet been studied extensively. Now, researchers tested antibiotic resistance profiles of a bacterial strain that until recently was hidden in a 5,000-year-old layer of ice of an underground ice cave—and found it could be an opportunity for developing new strategies to prevent the rise of antibiotic resistance and study how resistance naturally evolves and spreads. They reported their discovery in Frontiers in Microbiology.
The Psychrobacter SC65A.3 bacterial strain isolated from Scarisoara Ice Cave, despite its ancient origin, shows resistance to multiple modern antibiotics and carries over 100 resistance-related genes. But it can also inhibit the growth of several major antibiotic-resistant 'superbugs' and showed important enzymatic activities with important biotechnological potential.
Psychrobacter SC65A.3 is a strain of the genus Psychrobacter, which are bacteria adapted to cold environments. Some species can cause infections in humans or animals. Psychrobacter bacteria have biotechnological potential, but the antibiotic resistance profiles of these bacteria are largely unknown.
Studying microbes such as Psychrobacter SC65A.3 retrieved from millennia-old cave ice deposits reveals how antibiotic resistance evolved naturally in the environment, "long before modern antibiotics were ever used".
The team drilled a 25-meter ice core from the area of the cave known as the Great Hall, representing a 13,000-year timeline. To avoid contamination, the ice fragments taken from the core were placed in sterile bags and kept frozen on their way back to the lab. There, the researchers isolated various bacterial strains and sequenced their genome to determine which genes allow the strain to survive in low temperatures and which confer antimicrobial resistance and activity.
They tested for resistance of the SC65A strain against 28 antibiotics from 10 classes that are routinely used to or reserved for treating bacterial infections, including antibiotics that have previously been identified to possess resistance genes or mutations that give them the ability to resist drug effects. This way, they could test whether predicted mechanisms translated into measurable resistance.
The 10 antibiotics they found resistance to are widely used in oral and injectable therapies used to treat a range of serious bacterial infections in clinical practice.
Diseases such as tuberculosis, colitis, and UTIs can be treated with some of the antibiotics that the researchers found resistance to, including rifampicin, vancomycin, and ciprofloxacin.
SC65A.3 is the first Psychrobacter strain for which resistance to certain antibiotics—including trimethoprim, clindamycin, and metronidazole—was found. Those antibiotics are used to treat UTIs, infections of lungs, skin, or blood, and the reproductive system. SC65A.3's resistance profile suggests that strains capable of surviving in cold environments could act as reservoirs of resistance genes, which are specific DNA sequences that help them survive exposure to drugs. Bacterial strains like the one examined here hold both a threat and a promise. "If melting ice releases these microbes, these genes could spread to modern bacteria, adding to the global challenge of antibiotic resistance. On the other hand, they produce unique enzymes and antimicrobial compounds that could inspire new antibiotics, industrial enzymes, and other biotechnological innovations. In the Psychrobacter SC65A.3 genome, the researchers found almost 600 genes with unknown functions, suggesting a yet untapped source for discovering novel biological mechanisms. Analysis of the genome also revealed 11 genes that are potentially able to kill or stop the growth of other bacteria, fungi, and viruses. These ancient bacteria are essential for science and medicine.
First genome sequence and functional profiling of a Psychrobacter SC65A.3 preserved in 5,000-year-old cave ice: frominsights into ancient resistome, to antimicrobial potential and enzymatic activities, Frontiers in Microbiology (2026). DOI: 10.3389/fmicb.2025.1713017
Beyond 'survival' of fittest: Evolution works in teams Natural selection operates at multiple levels of biological organization, not just at the individual level. Empirical evidence from diverse species demonstrates that traits can be favoured or suppressed through both individual and group-level selection, sometimes in opposing directions. Recognizing multilevel selection provides a more comprehensive understanding of evolutionary processes and has practical implications in fields such as medicine and agriculture.
The common view of natural selection is based solely on the individual: A trait allows an organism to out-compete its rivals and is thus passed down to its offspring. To suggest otherwise can provoke the ire of certain segments of the scientific community.
But a bibliometric review of 280 scientific studies shows that natural selection can occur on multiple levels of biological organization simultaneously, and not just in social species.
The idea of looking at selection at multiple levels is to measure whether a trait is adaptive for individuals within a group. And does the frequency or existence of that trait within a group change the way the group functions in comparison with other groups?
The studies examined by the researchers spanned more than a century, covering everything from viruses to human beings. All attempted to account for multilevel selection (MLS), which provides a broader view of natural selection than individual benefit.
Why does multilevel selection remain controversial? Scientific culture. Since the 1960s, key scientists have observed that claims of group benefits weren't subject to rigorous measurement and shouldn't be taken seriously. Some scientists openly banned discussion of group selection in their classrooms, calling it naïve; others claimed that it was exceedingly rare or another term for kin selection.
If you measure the average increase in the frequency of a trait over generations and then say it's favoured by natural selection, you're not wrong
But what's the mechanism for the slow increase in that trait over here and the rapid increase over there?
If you had looked at different levels, you might see that group competition is more important in one place, or cooperation within groups in another.
Part 1
Imagine that there are two human tribes. In one, members are solely focused on their individual success. In the other, members are willing to sacrifice themselves for the good of the whole; however, this altruism may cost them time and resources that they could expend on their own children and personal survival.
Which tribe is more likely to survive a crisis, such as an attack from another group? The second. Paradoxically, the willingness for an individual to sacrifice for the group can lead to better survival outcomes. That doesn't mean that everyone in a group will become self-sacrificing, but that groups with self-sacrificing individuals may have a survival advantage.
To take a broader view, individuals not only live in communities but are communities. We are composed of trillions of cells, which comprise our tissues and organs, along with the bacteria in our microbiome and the viruses that afflict us. We live in families, neighborhoods, and countries, as well as ecosystems that bring us into contact with other species.
Every single one of these systems can change over time in response to stimuli, shifting and adapting in response to one another. Groupings can also influence individual success; consider, for example, the case of a family struggling with systemic poverty, or the impact of a troubled neighborhood on the individuals within it.Cancer is another interesting example, as are viral illnesses. On one hand, cancer cells no longer cooperate with the rest of the body, subverting the communal good for their individual benefit. But the situation isn't so cut-and-dry.
"In some cases, cancer cells act as a cooperative group in their own right; the ways they spread are strategic. You can also get competition between diseases for host resources But what happens within a host is not the whole story; the host's environment is critical, too. If a communicable disease exists in a host population with frequent and predictable contacts, rapid growth with damage to a host may evolve, because this will not stop the host from passing it on.
However, such diseases would soon die out in populations of more isolated individuals; in the second scenario, more benign versions would have the advantage, because longer surviving hosts would give the host—and its virus or bacteria—time to find another host. Thus, selection within hosts may favor disease organisms that reproduce faster, but selection between the groups of disease organisms defined by each host may be in the exact opposite direction. Multilevel selection complicates the picture because you have to consider all the places where selection could be occurring, and it's possible that selection on one level is headed in a different direction than selection on another level
Part 2
There is a real benefit to having a fuller picture of natural selection, particularly in medicine and agriculture. The role that widespread antibiotic use plays in shaping a bacterial arms race is a well-known example.
Another example involves chickens. In one famous study, the agricultural scientist William Muir focused on selecting for egg productivity of hens housed in battery cages. In one experiment, he selected the most productive hen within each cage to breed the next generation of hens (within-group selection). The result? A hyper-aggressive strain of hens that achieved their productivity at the expense of others, resulting in a decline in productivity at the cage level.
In a parallel experiment, Muir selected the most productive cages and used all the hens within the cages to breed the next generation of hens (group-level selection). The result? A docile strain of hens that didn't interfere with each other and achieved a 160% increase in productivity at the cage level in five generations. Based on this and other experiments, group-level selection has become standard practice in animal and plant breeding.
We can also apply the theory to ourselves, keeping Muir's chicken experiments in mind: Are we creating situations that reward competitive or even selfish behaviors? Consider a classroom that grades students on how many questions they ask, penalizing those who are quiet or slow to raise their hands. In that case, the class has selected for rapid responders rather than innovators or deep thinkers
Abundant empirical evidence of multilevel selection revealed by a bibliometric review, Frontiers in Ecology and Evolution (2026). doi.org/10.3389/fevo.2026.1752597
Not all humans are 'super-scary' to wildlife, animal behaviour study suggests Humans have climbed to the top of the food chain by skillfully hunting, trapping, and fishing for other animals at scales that far exceed other predators, altering how the animals behave and earning the tag of a "super-predator." But a new study led by the Center for Ecological Sciences, Indian Institute of Science (IISc), suggests that there is a bit more nuance to this idea. While animals clearly respond with fear to humans who hunt or kill, they are far less consistent in how they react to non-lethal human presence.
Zoos and eco-tourist spots? YES!
Wild animals show strong fear responses to lethal human activities like hunting, becoming more vigilant and reducing foraging, but react less consistently to non-lethal human presence. Human structures can sometimes decrease animal vigilance by providing perceived refuges. These behavioural changes influence survival, reproduction, and ecosystem dynamics, highlighting the need for nuanced conservation strategies. A comprehensive meta-analysis, published in Ecology Letters, analyzes three decades of research on how wild animals change their behavior in response to different types of human interactions. The study examined behavioural shifts in foraging, vigilance, and movement across species and ecosystems to look into whether humans are always super-scary.
"The short answer is: no, not always" Researchers found strong evidence that lethal humans such as hunters and fishers are indeed perceived as threatening. Animals in areas exposed to lethal humans tend to be more vigilant and spend less time foraging. In contrast, responses to non-lethal humans such as tourists or researchers are weaker and more variable. The study's findings broadly support the "risk allocation hypothesis," which suggests that animals adjust their behaviour based on how intense and predictable a threat is. When danger is high and consistent, animals stay cautious. When risk is low or predictable, they can afford to relax. Beyond individual behaviour, the researchers point to a bigger picture. Changes in fear and behaviour can cascade through ecosystems, altering grazing, predation, and ecological balance.
Shawn Dsouza et al, Are Human Super‐Predators Always Super‐Scary? A Meta‐Analysis of Wild Animal Behavioural Responses to Human Interactions, Ecology Letters (2025). DOI: 10.1111/ele.70287
Dr. Krishna Kumari Challa
Boxfish
Feb 11
Dr. Krishna Kumari Challa
Fever chills explained: How brain signals push warmth-seeking to fight infection
When running a fever during infection, we often feel chills, which prompt us to take action to warm ourselves, such as turning on a heater or adding layers of clothing. Increased body temperature helps inhibit pathogen growth and boosts immune cell activity.
A recent rat study by researchers identified the neural mechanism underlying chills, a cold sensation that supports the body's response to infection. The findings were published in The Journal of Physiology.
When mammals are infected, their immune system produces a pyrogenic mediator, prostaglandin E₂ (PGE₂), in the brain's vascular cells. PGE₂ acts on the preoptic area, the brain's thermoregulatory center, and triggers autonomic fever responses, such as shivering, increased heat production in brown adipose tissue, and constriction of skin blood vessels.
PGE₂ is known to trigger not only autonomic fever responses but also behavioral fever responses including warming behaviors with chills.
The team hypothesized that PGE₂ acts on the lateral parabrachial nucleus (LPB) in the brain, which relays sensory signals, to trigger chills and warmth-seeking behaviors during infection. This was based on their 2023 study showing that LPB neurons transmit skin-temperature sensations to the forebrain and influence body temperature regulation. To test this hypothesis, the team conducted experiments on rats.
The researchers found that the rats' axons primarily target the central nucleus of the amygdala, which regulates emotions such as discomfort and fear, with minimal projections to the preoptic area.
The team also found that the pathway from EP3-expressing neurons to the amygdala is activated in cold environments and transmits cold sensations.
These findings suggest that during infection, PGE₂ boosts cold signals from the LPB to the central nucleus of the amygdala via EP3 receptors, triggering chills and promoting warmth-seeking behaviour.
This study demonstrates that PGE₂ increases body temperature by acting on two brain regions: the preoptic area, which drives autonomous thermogenic responses, and the lateral parabrachial nucleus (LPB), which mediates behavioural responses.
The pyrogenic mediator prostaglandin E2 elicits warmth seeking via EP3 receptor-expressing parabrachial neurons: a potential mechanism of chills, The Journal of Physiology (2026). DOI: 10.1113/JP289466
Feb 11
Dr. Krishna Kumari Challa
Only humans have chins and it's an evolutionary accident
Every chin is distinctive in the sense that humans are the only primates to possess that physical characteristic.
Chimpanzees, humans' closest living relatives, do not have a chin. Neither did Neanderthals, Denisovans, or any other extinct human species. Humans, it turns out, have a unique capacity to "take it on the chin" because we're uniquely in possession of that physical feature. That exclusive nature makes the chin well suited for identifying Homo sapiens in the fossil record.
The chin evolved largely by accident and not through direct selection, but as an evolutionary by-product resulting from direct selection on other parts of the skull.
The chin is a spandrel, a feature that arises as an unintended byproduct of evolution, just as the space under a staircase exists not for any architectural purpose, but as a byproduct of building a convenient way to get from one level to the next.
Just because we have a unique feature, like the chin, does not mean that it was shaped by natural selection to enhance an animal's survivability, for example, a buttress for the lower jaw to help dissipate the forces of chewing. The chin is likely a byproduct, not an adaptation.
Noreen von Cramon-Taubadel et al, Is the human chin a spandrel? Insights from an evolutionary analysis of ape craniomandibular form, PLOS One (2026). DOI: 10.1371/journal.pone.0340278
Feb 12
Dr. Krishna Kumari Challa
The origin of magic numbers: Why some atomic nuclei are unusually stable
A new model explains the stability of magic nuclei by directly linking their shell structure to underlying proton–neutron interactions via nuclear wavefunctions. This approach naturally reproduces magic numbers and bridges phenomenological and first-principles nuclear models, offering insights into the strong nuclear force and the properties of heavy, exotic nuclei.
C. R. Ding et al, From Spin to Pseudospin Symmetry: The Origin of Magic Numbers in Nuclear Structure, Physical Review Letters (2026). DOI: 10.1103/8lzc-j1lx. On arXiv: DOI: 10.48550/arxiv.2504.09148
Feb 12
Dr. Krishna Kumari Challa
Space mining without heavy machines? Microbes harvest metals from meteorites aboard space station
Microbes can extract valuable metals from meteorites in microgravity, with fungi notably enhancing palladium release. Microbial biomining remains effective in space, while nonbiological leaching is less efficient under microgravity. Extraction rates vary by metal, microbe, and gravity, highlighting the complexity and potential of microbial resource extraction for space and Earth applications.
Rosa Santomartino et al, Microbial biomining from asteroidal material onboard the international space station, npj Microgravity (2026). DOI: 10.1038/s41526-026-00567-3
Feb 12
Dr. Krishna Kumari Challa
Nanoplastics hindering cognitive abilities of fish, international research shows
Plastic makes up about 80 to 85% of marine litter, according to environmental research, with the most commonly used plastics breaking down into smaller pieces under ultraviolet light and low temperatures.
Nanoplastic exposure can impair the cognitive abilities of fish and could lead to significant impacts on marine species' ability to survive, according to a new international study.
Exposure to nanoplastics impairs cognitive function in marine medaka (Oryzias melastigma), leading to increased errors and impulsive decision-making during behavioral tests. These changes may reduce survival by affecting foraging, predator avoidance, and reproduction. Nanoplastics, due to their small size, are highly bioavailable and pose a significant, underrecognized threat to marine ecosystems.
The important things for any animal are reproduction, shelter and feed. For a fish which has changed its behavior, it may have trouble capturing food and most importantly, have trouble avoiding predators.
It may also be affected when mating and finding a mate, let alone spawning. There are huge potential effects on those three basic requirements for survival.
Xianyu Yuan et al, Nanoplastic exposure damages neural plasticity, cognitive abilities, and ecological adaptability of marine medaka Oryzias melastigma, Marine Pollution Bulletin (2026). DOI: 10.1016/j.marpolbul.2026.119232
Feb 12
Dr. Krishna Kumari Challa
No association between mRNA COVID-19 vaccination during pregnancy and autism in children, new research shows
Children born to mothers who received an mRNA COVID-19 vaccine during or shortly before pregnancy show no increased risk of autism or other neurodevelopmental problems at 18–30 months compared to children of unvaccinated mothers. Neurodevelopmental assessments revealed no significant differences between the groups, supporting the vaccine's safety in pregnancy.
Association between SARS-CoV-2 vaccine in pregnancy and child neurodevelopment at 18–30 months, Pregnancy (2026).
Feb 12
Dr. Krishna Kumari Challa
Elephant whiskers exhibit material intelligence for touch sensing
on Friday
Dr. Krishna Kumari Challa
Failed supernova provides clearest view yet of a star collapsing into a black hole
Astronomers have watched a dying star fail to explode as a supernova, instead collapsing into a black hole. The remarkable sighting is the most complete observational record ever made of a star's transformation into a black hole, allowing astronomers to construct a comprehensive physical picture of the process.
Combining recent observations of the star with over a decade of archival data, the astronomers confirmed and refined theoretical models of how such massive stars turn into black holes. The team found that the star failed to explode as a supernova at the end of its life; instead, the star's core collapsed into a black hole, slowly expelling its turbulent outer layers in the process.
The discovery will help explain why some massive stars turn into black holes when they die, while others don't.
The now-deceased star, called M31-2014-DS1, is located around 2.5 million light-years away from Earth in the neighbouring Andromeda galaxy.
They found that M31-2014-DS1's infrared light began brightening in 2014. Then in 2016, the star swiftly dimmed far below its original luminosity in barely a year.
Observations in 2022 and 2023 showed that the star essentially vanished in visible and near-infrared light, becoming one ten-thousandth as bright in these wavelengths. Its remnant is now only detectable in mid-infrared light, where it shines at a mere one-tenth as bright as before.
Comparing these observations with theoretical predictions, the researchers concluded that the star's dramatic fading to such a small fraction of its original total brightness provides strong evidence that its core collapsed and became a black hole.
Stars fuse hydrogen into helium in their cores, and that process generates outward pressure to balance the incessant inward pull of gravity. When a massive star roughly 10 or more times heavier than our sun begins to run out of fuel, the balance between inward and outward forces is disrupted. Gravity begins to collapse the star, and its core succumbs first to form a dense neutron star at the center.
Often, the emission of neutrinos in this process generates a powerful shock wave that is explosive enough to rip apart most of the core and outer layers in a supernova. However, if the neutrino-powered shock wave fails to push the stellar material out, theory has long suggested that most of the stellar material would instead fall back into the neutron star, forming a black hole.
Kishalay De, Disappearance of a massive star in the Andromeda Galaxy due to formation of a black hole, Science (2026). DOI: 10.1126/science.adt4853. www.science.org/doi/10.1126/science.adt4853
Part 1
on Friday
Dr. Krishna Kumari Challa
The observations and analysis of M31-2014-DS1 enabled the team to reinterpret observations of a similar star, NGC 6946-BH1. This led to an important breakthrough in understanding what had happened to the outer layers that had enveloped the star after it failed to go supernova and collapsed into a black hole. The overlooked element? Convection.
Convection is a byproduct of the vast temperature differences inside the star. Material near the star's center is extremely hot, while the outer regions are much cooler. This differential causes gases within the star to move from hotter to cooler regions.
When the star's core collapses, the gas in its outer layers is still moving rapidly due to this convection. Theoretical models developed by astronomers at the Flatiron Institute have shown that this prevents most of the outer layers from falling directly in; instead, the innermost layers orbit outside of the black hole and drive the ejection of the outermost layers of the convective region.
The ejected material cools as it moves farther from the hot material around the black hole. This cool material readily forms dust as atoms and molecules combine. The dust obscures the hot gas orbiting the black hole, warming the dust and producing an observable brightening in infrared wavelengths. This lingering red glow is visible for decades after the star itself disappears.
Kishalay De, Disappearance of a massive star in the Andromeda Galaxy due to formation of a black hole, Science (2026). DOI: 10.1126/science.adt4853. www.science.org/doi/10.1126/science.adt4853
Part 2
on Friday
Dr. Krishna Kumari Challa
Why visceral fat triggers diabetes: Study points to loss of protective macrophages
Scientists discovered a surprising new way the body can fight insulin resistance and diabetes—by boosting a special type of "good" immune cell in fat tissue.
Reported in Nature Communications, the preclinical findings pave the path to developing a medication to treat and prevent type 2 diabetes, potentially replacing or supplementing GLP-1 weight maintenance drugs that lose effectiveness over time.
One-third of our population is obese or overweight—over the next decade or so, obesity will drive increasing rates of many chronic diseases, including diabetes.
Inflammation driven by immune signals given off by excess fat surrounding abdominal organs has long been known to trigger the insulin resistance that leads to type 2 diabetes.
The researchers found is that there is a subset of immune cells in our fat tissue that are actually helpful. Although they're immune cells, they're not inflammatory—rather, they actually suppress the inflammation that causes insulin resistance.
This subset of immune cells—called resident macrophages—clean up dead cells, fight infections and keep tissues healthy. SerpinB2 is a protein that helps resident macrophages survive. When too much visceral fat accumulates—which occurs when someone is overweight or obese—inflammation increases and SerpinB2 levels plummet.
This causes resident macrophages to die out, which allows fat tissue to grow larger and become more inflamed. Ultimately, the body can't respond as well to insulin, which controls blood sugar, and the person develops diabetes.
When overweight mice with insulin-resistance were given antioxidant supplements, their levels of resident macrophages increased and their insulin sensitivity improved.
Tissue-resident macrophage survival depends on mitochondrial function regulated by SerpinB2 in chronic inflammation, Nature Communications (2026). DOI: 10.1038/s41467-026-69196-4
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Dr. Krishna Kumari Challa
Light-based sensor detects early molecular signs of cancer in the blood
Researchers have developed a highly sensitive light-based sensor that can detect extremely low concentrations of cancer biomarkers in the blood. The new technology could one day make it possible to spot early signs of cancer and other conditions using a simple blood test.
Biomarkers such as proteins, DNA or other molecules can be used to reveal the presence, progression or risk of cancer and other diseases. However, one of the main challenges in early disease diagnosis is the extremely low concentration of biomarkers present at the onset.
The new sensor developed now combines nanostructures made of DNA with quantum dots and CRISPR gene editing technology to detect faint biomarker signals using a light-based approach known as second harmonic generation (SHG).
This approach could help make disease treatments simpler, potentially improve survival rates and lower overall health care costs.
Wenbo Du et al, Sub-Attomolar-Level Biosensing of Cancer Biomarkers Using SHG Modulation in DNA-Programmable Quantum Dots/MoS2 Disordered Metasurfaces, Optica (2026). DOI: 10.1364/optica.577416
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Dr. Krishna Kumari Challa
Plants retain a 'genetic memory' of past population crashes, study shows
Plant populations that have experienced past crashes due to human activity retain reduced genetic diversity and increased inbreeding, even after apparent recovery. These genetic effects persist for many generations and are not reflected by current population size alone, highlighting the importance of considering genetic history in conservation planning to ensure long-term resilience.
Researchers have found that plants living in areas where human activity has caused population crashes carry long-lasting genetic traces of that history, such as reduced genetic diversity. Because genetic diversity helps species adapt to climate change, disease, and other stresses, the study suggests it is vital to consider a population's history-influenced genetics alongside its size and habitat in conservation planning.
Two populations may look equally healthy on the surface, yet one may be far more vulnerable to future environmental change because it lacks genetic diversity and consists of individuals with poorly mixed genetic material. This can impede evolutionary responses to changing conditions.
Daniel J. Schoen et al, Population genomic signatures of founding events in autonomously self‐fertilizing plants: a test with Impatiens capensis, New Phytologist (2026). DOI: 10.1111/nph.70880
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Dr. Krishna Kumari Challa
Cholesterol crystals may trigger some liver disease
Cholesterol crystals in the liver can increase tissue stiffness early in metabolic dysfunction-associated steatotic liver disease (MASLD), preceding fibrosis. This process may contribute to disease progression and could help identify individuals at higher risk for severe liver damage. Non-invasive detection methods and cholesterol-lowering treatments may offer new avenues for early intervention.
David Li et al, Cholesterol-containing lipid crystals can directly stiffen the rat steatotic liver before fibrosis, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2518060123
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Dr. Krishna Kumari Challa
Scientists discover new gatekeeper cell in the brain
A previously unidentified population of base barrier cells has been found at the base of the choroid plexus, forming a tight junction-based barrier that compartmentalizes the brain, choroid plexus, and cerebrospinal fluid. This barrier restricts molecular movement under healthy conditions but becomes vulnerable during systemic inflammation, potentially allowing harmful substances into the brain. These cells are present in both mice and humans.
Daan Verhaege et al, Base barrier cells provide compartmentalization of choroid plexus, brain and CSF, Nature Neuroscience (2026). DOI: 10.1038/s41593-025-02188-7
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Dr. Krishna Kumari Challa
Traffic noise linked to higher cholesterol and lipid levels in blood
Long-term exposure to nighttime road traffic noise above 50–55 dB is associated with higher blood levels of total cholesterol, LDL cholesterol, and other lipid-related metabolites, which are established risk factors for cardiometabolic diseases. These metabolic changes show a clear exposure-response pattern, suggesting that reducing nighttime noise could benefit public health.
Yiyan He et al, Metabolic profiles of nighttime road traffic noise exposure: A multi-cohort study in the European LongITools project, Environmental Research (2026). DOI: 10.1016/j.envres.2026.123887
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Dr. Krishna Kumari Challa
AI is distorting online research, from polls to public policy
AI systems can now convincingly simulate human responses in online surveys and polls, undermining the reliability of survey-based research and public policy data. Traditional safeguards like CAPTCHAs and attention checks are increasingly ineffective. New strategies, including behavioural analysis and tasks exploiting human error patterns, are needed to maintain data integrity as AI advances.
Folco Panizza et al, How to deal with the survey-taking AI agents that threaten to upend social science, Nature (2026). DOI: 10.1038/d41586-026-00386-2
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Dr. Krishna Kumari Challa
Fungi flip mattresses into useful materials
Material from discarded mattresses can be upcycled into fire-resistant insulation with the help of a fungus. Researchers mixed polyurethane foam from mattresses into a nutrient-rich liquid and added spores of the fungus Penicillium chrysogenum. The fungus produced deposits of calcium carbonate as it grew, which meshed with the foam to form a lightweight material that could withstand temperatures up to around 1000 °C. Through natural biological processes, we can give this waste a second life.
https://www.nature.com/articles/s41598-025-30954-x?utm_source=Live+...
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Dr. Krishna Kumari Challa
A feast to the eyes
Intelligence or interest creation? Whatever it is, if it runs in the families, you can have pics like this.
On the left is the legendary physicist Niels Bohr,who received the Nobel Prize in 1922 for his groundbreaking research on the electron shell and quantized energy level.
Right next to him, Aage Niels Bohr (he was drawing numbers on the board ) who later won the Nobel Prize in Physics in 1975.
Aage Bohr and his father, Niels, are one of the few father-son pairs to both receive Nobel Prizes in Physics, separated by 53 years.
From 1946, father and son were simultaneously doing research at the Niels Bohr Institute.
The little child in the picture who is quietly coming forward and calculating with his grandfather and father is Thomas Bohr, another legendary physicist of this family.
He is a professor at the Technical University of Denmark and his research on macroscopic fluid dynamic systems is well known.
on Friday
Dr. Krishna Kumari Challa
Organic molecule stores solar energy for years, then releases it as heat on demand
When the sun goes down, solar panels stop working. This is the fundamental hurdle of renewable energy: how to save the sun's power for a rainy day—or a cold night. Chemists have developed a solution that doesn't require bulky batteries or electrical grids. In a paper published in the journal Science, they detail a new material that captures sunlight, stores it within chemical bonds and releases it as heat on demand.
The material, a modified organic molecule called pyrimidone, is the latest advancement in molecular solar thermal (MOST) energy storage.
To create this molecule, the team looked to a surprising source: DNA. The pyrimidone structure is similar to a component found in DNA that, when exposed to UV light, can undergo reversible structural changes.
By engineering a synthetic version of this structure, the team created a molecule that stores and releases energy reversibly.
Traditional solar panels convert light into electricity; however, most systems convert light into chemical energy. The molecule acts like a mechanical spring: when hit with sunlight, it twists into a strained, high-energy shape. It stays locked in that shape until a trigger—such as a small amount of heat or a catalyst—snaps it back to its relaxed state, releasing the stored energy as heat.
The team's new molecule is a heavy hitter. It boasts an energy density of more than 1.6 megajoules per kilogram. That is roughly double the energy density of a standard lithium-ion battery—which comes in at around 0.9 MJ/kg—and significantly higher than previous generations of optical switches.
Han P. Q. Nguyen et al, Molecular solar thermal energy storage in Dewar pyrimidone beyond 1.6 MJ/kg, Science (2026). DOI: 10.1126/science.aec6413
on Sunday
Dr. Krishna Kumari Challa
Why you hardly notice your blind spot: New tests pit three theories of consciousness
Although humans' visual perception of the world appears complete, our eyes contain a visual blind spot where the optic nerve connects to the retina. Scientists are still uncertain whether the brain fully compensates for the blind spot or if it causes perceptual distortions in spatial experience. A new study protocol, published in PLOS One, seeks to compare different theoretical predictions on how we perceive space from three leading theories of consciousness using carefully controlled experiments.
Predictions from three theories of consciousness
The new protocol focuses on three contrasting theories of consciousness: Integrated Information Theory (IIT), Predictive Processing Active Inference (AI), and Predictive Processing Neurorepresentationalism (NREP). Each of the theories have different predictions about the effects that the blind spot's structural features have on the conscious perception of space, compared to non-blind spot regions.
IIT argues that the quality of spatial consciousness is determined by the composition of a cause-effect structure, and that the perception of space involving the blind spot is altered. On the other hand, AI and NREP argue that perception relies on internal models that reduce prediction errors and that these models adapt to accommodate for the structural deviations resulting from the blind spot. Essentially, this means that perceptual distortions should either appear small or nonexistent in both theories. However, AI and NREP differ in some ways.
"Specifically, NREP posits that lesions of portions of the visual field can have an effect on spatial estimates, but will be largely compensated for by the sensory evidence available from intact portions of the visual field.
According to AI, the quality of spatial experience is determined by the cause-effect structure under a generative model apt for active vision. This model of projective geometry is not the geometry of anatomical projections. Thus, AI proposes that perceptual judgments should not be altered when involving the blind spot, other than possible changes in perceptual uncertainty, due to differences in sensory sampling," the protocol authors explain.
Part 1
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Dr. Krishna Kumari Challa
To test out the three theories, the researchers put together a series of three psychophysical tasks, which include distance estimation, area size matching, and motion curvature judgment, all near or away from the blind spot. The tasks use colored glasses for dichoptic presentation, which allows for stimuli to be shown to one eye at a time. The study also utilizes eye tracking to ensure accurate fixation and to prevent unintentional stimulation of the blind spot.
The research team also conducted analysis with simulated data of IIT, NREP and AI predictions for their distance estimation task, area size task and motion curvature task. The simulated data showed that IIT predicts spatial warping near the blind spot, while AI and NREP predict little or no distortion, with possible small decreases in precision.
As with most studies, there are potential limitations in interpreting the data when the actual experiments take place. For example, the theories in question predict the direction but not the magnitude of effects, making interpretation challenging.
The team also notes that unexpected results, such as an object appearing larger when it is predicted to appear smaller, may not be easily explained by any theory. Still, studies using the protocol have the potential to address some fundamental questions about how we perceive a seamless world with gaps in sensory input and may even advance the understanding of consciousness.
Clement Abbatecola et al, Protocol for investigating the warping of spatial experience across the blind spot to contrast predictions of the Integrated Information Theory and Predictive Processing accounts of consciousness, PLOS One (2026). DOI: 10.1371/journal.pone.0340593
Part 2
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on Sunday
Dr. Krishna Kumari Challa
The discovery of a tiny RNA molecule and clues to origin of life
One of the greatest mysteries of our planet is how a soup of lifeless chemicals transformed into the first living cell. There are several competing theories about where this happened, from frozen polar ice to superheated hydrothermal vents. But one thing that most scientists agree on is that life could not begin until a molecule appeared that could spontaneously copy itself.
For decades, the RNA World hypothesis has proposed that RNA was that molecule and that it proliferated before the evolution of DNA and proteins. This RNA had to be able to store genetic information and also build things such as new RNA strands.
However, there is a major problem with this school of thought: the RNA molecules (ribozymes) that we know can copy other RNA molecules are large and complex. That means it is highly unlikely they would have formed spontaneously in the primordial soup.
But a new candidate has emerged that might solve this puzzle. In a study published in the journal Science, researchers report the discovery of a small RNA molecule called QT45.
They found it after searching through a vast library of 12 trillion random RNA sequences. They were looking for any snippets of RNA that could act as a polymerase—a molecular builder. When the team found a few promising candidates, they put them through a molecular version of the survival-of-the-fittest test. They challenged them to build longer and longer chains under increasingly tougher conditions. QT45 emerged as the winner.
The scientists then ran experiments in a slushy, salty mixture of ice crystals and liquid to mimic conditions of early Earth. In this lab setting, QT45, which comprises just 45 nucleotides, proved it could act as a polymerase. It built a complementary RNA strand and then used that as a template to create a brand-new copy.
The study shows that the complex functions needed for RNA replication... can all be performed by an RNA motif of just 45 nucleotides.
According to the study authors, if a molecule this tiny is capable of performing complex tasks like building new strands and copying itself, life-starting molecules are likely to be more common.
Edoardo Gianni et al, A small polymerase ribozyme that can synthesize itself and its complementary strand, Science (2026). DOI: 10.1126/science.adt2760
on Sunday
Dr. Krishna Kumari Challa
Why phage contamination is hard to kill, and how charged nanoparticles could help
Bacteriophages are viruses that can kill bacteria through highly specific interactions. While this property can be beneficial in selected applications, bacteriophages represent a serious threat to laboratories and industries that rely on bacterial cultures for production. Their selective inactivation remains a major challenge. Recently, researchers demonstrated an innovative solution that enables targeting the surface of bacteriophage through electrostatic interactions as a promising strategy for their inactivation without adversely affecting bacterial strains or eukaryotic cells.
Decades ago, antibiotics were considered wonder drugs capable of curing bacterial infections. Unfortunately, overuse of these drugs led to the development of antibiotic-resistance in many pathogenic bacterial strains, raising global concern. One of the solutions to defeat these pathogens is bacteriophages, also called phages. While phages are explored as therapeutic agents in medicine, their presence is highly undesirable in laboratories and industrial processes that depend on carefully controlled bacterial cultures.
In many industrial sectors, including food fermentation, enzyme, pharmaceuticals, and cosmetics production, specific bacterial strains are essential for efficient and reproducible manufacturing. In these settings, bacteriophages pose a major risk, as they can selectively infect and eliminate production strains, leading to failed batches and significant economic losses. Phages may also appear in agriculture or wastewater treatment environments, where their presence can influence microbial populations, but in controlled bioprocesses their uncontrolled spread is particularly detrimental.
Despite their small size, bacteriophages are highly persistent and can easily spread within laboratory and industrial environments. They may be introduced through contaminated raw materials, inadequately disinfected equipment, surfaces, or even air. Once present, phages can rapidly propagate within bacterial cultures, often remaining undetected until the entire system collapses due to bacterial lysis.
To prevent phage contamination, laboratories and factories rely on strict hygiene protocols involving sterilization and disinfection methods such as UV-C radiation, high temperature and pressure, ozone, and aggressive chemicals including potassium peroxymonosulfate (Virkon), ethanol, bleach, and hydrogen peroxide. These approaches typically aim to damage phage capsid proteins or nucleic acids, thereby inactivating the virus.
However, bacteriophages can aggregate, increasing their resistance to harsh environmental conditions such as heat or chemical exposure. Moreover, phages are often more resilient than bacteria themselves. As a result, disinfection methods strong enough to eliminate phages frequently destroy the bacterial strains required for industrial processes. This lack of selectivity represents a critical limitation of existing anti-phage strategies and drives the search for safer, more effective solutions.
Part 1
Bacteriophage contamination is difficult to eliminate due to phages’ persistence and resistance to standard disinfection, which often harms beneficial bacteria. Charged polypyrrole nanoparticles with 1% carboxyl groups selectively inactivate phages via electrostatic interactions, sparing bacteria and eukaryotic cells, and show low cytotoxicity, offering a scalable, targeted solution for bioprocess protection.
on Sunday
Dr. Krishna Kumari Challa
Addressing these challenges, the interdisciplinary team of researchers propose a solution that enables the selective killing of phages without any harmful effect on bacteria. Their latest work, published in Materials & Design, shows an innovative approach based on polymeric nanospheres having a well-defined surface that interacts with bacteriophages.
Bacteriophages possess characteristic surface charges that differ from those of bacterial and eukaryotic cells. The researchers designed polypyrrole nanoparticles (NPs) that interact directly with charges on the phage surface through electrostatic interactions. Because the biological membranes of bacteria and human cells have different surface properties than bacteriophages, they are not affected, and the charged polypyrrole NPs act selectively on phages.
Importantly, the present study demonstrates that selective antiphage activity can be achieved using polymer-based nanoparticles, offering a significantly cheaper and scalable alternative to other nanostructural solutions like gold-based systems.
The proposed nanoparticles are approximately 50 nm in diameter and contain specific chemical groups on their surface, namely negatively charged carboxylic groups, which enhance electrostatic interactions with bacteriophages. The researchers controlled the density of these groups during fabrication by polymerizing mixtures of pyrrole with and without carboxylic modifications.
Importantly, they identified an optimal surface composition required for effective phage inactivation.
The cytotoxicity studies that were performed on fibroblasts demonstrated that the nanoparticles were biocompatible at concentrations effective for phage inactivation. The irreversible inactivation of phages along with minor cytotoxicity shows the potential of the proposed NP in biotechnology, antimicrobial, and medical applications.
Sada Raza et al, Targeted inactivation of bacteriophages by polypyrrole nanoparticles, Materials & Design (2025). DOI: 10.1016/j.matdes.2025.115204
part 2
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on Sunday
Dr. Krishna Kumari Challa
Polluting the environment for all eternity—and still sticking our heads in the sand
Plastic pollution persists in the environment, breaking down into microplastics and releasing PFAS and heavy metals at levels exceeding safety thresholds in small freshwater ecosystems. These contaminants threaten wildlife and human health. Despite global and national targets, current cleanup efforts and funding are insufficient, and long-term, coordinated action is urgently needed.
Hilde Ervik et al, Organic contaminants and toxic elements in marine plastic debris, water and sediments in small freshwater lakes in a Norwegian coastal archipelago, Heliyon (2026). DOI: 10.1016/j.heliyon.2025.e44232
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Dr. Krishna Kumari Challa
Scientists decipher how two bacterial species cooperate to avoid being eaten
Pseudomonas and Paenibacillus bacteria cooperate to evade amoeba predation by modifying the lipopeptide syringafactin. Pseudomonas produces syringafactin, which Paenibacillus activates via DL peptidases, converting it into an amoeba-toxic compound. This mechanism highlights a specific enzymatic cleavage of D/L-configured lipopeptides, aiding future natural product analysis and anti-infective development.
Shuaibing Zhang et al, Microbial DL-Peptidases Enable Predator Defense and Facilitate Structure Elucidation of Complex Natural Products, Journal of the American Chemical Society (2026). DOI: 10.1021/jacs.5c17955
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Dr. Krishna Kumari Challa
How did humans develop sharp vision? Lab-grown retinas show likely answer
Sharp human vision develops in early fetal life through the combined action of retinoic acid, which limits blue cone formation, and thyroid hormones, which convert blue cones into red and green cones in the foveola. This process establishes the unique cone distribution essential for high-acuity vision and may inform future therapies for retinal diseases.
Katarzyna A. Hussey et al, A cell fate specification and transition mechanism for human foveolar cone subtype patterning, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2510799123
on Sunday
Dr. Krishna Kumari Challa
Science academies failing to put women at the top
Women now comprise about 19% of science academy members, up from 12% in 2015, but leadership roles remain largely male-dominated, with only one in five academies chaired by a woman and nearly half lacking women as vice-presidents or co-chairs. Women are 2.5 times more likely than men to report discrimination or harassment, and institutional mechanisms to address misconduct are often viewed as inadequate.
National science organizations may have more women members today than a decade ago, but representation at the highest level has failed to keep pace, according to analysis published on International Day of Women and Girls in Science.
The International Science Council (ISC), InterAcademy Partnership (IAP) and Standing Committee for Gender Equality in Science (SCGES) looked at data from 136 scientific organizations and surveyed nearly 600 scientists to get a picture of gender equality across science academies and unions worldwide.
They found that women made up around 19% of science academy members in 2025–up from 12% in 2015. But only one in five academies was chaired by a woman and almost half had no women as vice-presidents or co-chairs, representing a "very limited increase" in the last decade and no progress in the last five years, according to their report.
Science academies play a role in shaping research agendas and standards across different disciplines and advising policymakers.
On paper, most science organizations promote themselves as open and inclusive, with election procedures based on academic merit. But informal networks persist that determine who is put forward for leadership roles, the report suggests.
Additionally, women are 2.5 times more likely than men to report experiences of discrimination or harassment within scientific organizations and show less confidence in organizational mechanisms to address misconduct, it says.
Towards gender equality in scientific organization: assessment and recommendations. www.interacademies.org/publica … -and-recommendations
Carolina Espinosa Luna et al, Economías de legitimidad abusiva: explicación sociológica de la violencia académica contra mujeres, Estudios Sociológicos de El Colegio de México (2026). DOI: 10.24201/es.2026v44.e2873
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Dr. Krishna Kumari Challa
Asian elephants can read human body language
Body and face orientation both matter when elephants decide it’s worth communicating.
Elephants are often celebrated for their intelligence and emotional depth, but how much do they actually understand about us?
A study conducted at the Golden Triangle Asian Elephant Foundation in Chiang Rai, Thailand, suggests that Asian elephants (Elephas maximus) are highly perceptive of human attention, as they read visual cues that signal whether communication is even worth attempting.
Ten captive female Asian elephants were observed as an experimenter stood before them in four different orientations: facing them fully, turning away entirely, or showing only body or only face.
When both the experimenter's body and face were oriented toward them, the elephants gestured the most frequently. Body orientation emerged as a stronger cue than facial direction, but only when paired with eye contact. Neither signal alone was enough to significantly prompt communication.
So if you ever have the opportunity to interact with an elephant, make sure you pay full attention with your body language.
Asian elephants (Elephas maximus) recognise human visual attention ...
on Monday
Dr. Krishna Kumari Challa
Antifungals are ‘ampho-terrible’ no more
Scientists have identified a molecule that acts as a plug to clog proteins that are critical for the toxicity of the dangerous fungus Cryptococcus. The notoriously drug-resistant fungus causes symptoms similar to pneumonia and is particularly dangerous for people with compromised immune systems. Currently, the go-to drug class is amphotericin, deemed “ampho-terrible” by biochemist Gerry Wright. “Fungal cells are a lot like human cells, so the drugs that hurt them tend to hurt us too,” he says. “That’s why there are so few options available to patients.” After a decade of research, researchers discovered butyrolactol A, which acts as an adjuvant to make Cryptococcus more susceptible to other drugs.
Butyrolactol A enhances caspofungin efficacy via flippase inhibitio...
Discovery could lead to new treatments for drug-resistant fungal infections
Fungal infections kill millions of people each year, and modern medicine is struggling to keep up. But researchers have identified a molecule that may help turn the tide — butyrolactol A, a chemical compound that targets a deadly, disease-causing fungi called Cryptococcus neoformans.
Infections caused by Cryptococcus are extremely dangerous. The pathogen, which can cause pneuomia-like symptoms, is notoriously drug-resistant, and it often preys on people with weakened immune systems, like cancer patients or those living with HIV. And the same can be said about other fungal pathogens, like Candida auris or Aspergillus fumigatus — both of which, like Cryptococcus, have been declared priority pathogens by the World Health Organization. Despite the threat, though, doctors have only three treatment options for fungal infections
The gold standard is a drug class called amphotericin - that is often called “amphoterrible,” because of the major toxic side-effects that it has on humans.
“Fungal cells are a lot like human cells, so the drugs that hurt them tend to hurt us too. That’s why there are so few options available to patients.”
The other two antifungal drug classes that are available — azoles and echinocandins — are much less effective treatment options, especially against Cryptococcus.
So, with a stagnant antifungal drug pipeline, a limited arsenal of approved medicines, and rising rates of drug resistance, scientists are now betting on something called “adjuvants” as a solution to the growing health threat.
Adjuvants are helper molecules that don’t actually kill pathogens like drugs do, but instead make them extremely susceptible to existing medicine.
Part 1
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Dr. Krishna Kumari Challa
The researchers found butyrolactol A, a known-but-previously-understudied molecule produced by certain Streptomyces bacteria. The researchers found that the molecule could synergize with echinocandin drugs to kill fungi that the drugs alone could not.
Discovery could lead to new treatments for drug-resistant fungal in...
Part 2
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Dr. Krishna Kumari Challa
A common biomarker of schizophrenia and bipolar disorder revealed
For decades, schizophrenia and bipolar disorder (BD) were treated as distinct and unrelated psychiatric disorders. Schizophrenia is a psychiatric disorder characterized by altered thinking and emotional patterns, hallucinations, false or irrational beliefs (i.e., delusions), cognitive deficits, and disorganized speech. BD, on the other hand, is marked by extreme mood swings, ranging between periods of high-energy (i.e., mania or hypomania) and depressive episodes.
While the symptoms of schizophrenia and BD are markedly different, many patients diagnosed with either of these conditions experience psychosis at least once in their lifetime. Psychosis is a mental state that causes people to lose touch with reality, experiencing hallucinations, delusions, disorganized speech, and irrational thinking patterns.
More recently, studies found that patients diagnosed with schizophrenia and BD sometimes share other overlapping symptoms, as well as common patterns in their genes and brain organization. This inspired the idea that these disorders are part of a shared psychosis spectrum, which would explain their common features and characteristics.
Researchers reviewed and analyzed the findings of previous studies to further test this hypothesis and validate the existence of a psychosis spectrum of disorders. Their paper, published in Nature Mental Health, outlines common brain features in patients with schizophrenia and BD, particularly differences in the integrity of white matter.
As part of their study, the researchers systematically reviewed brain imaging data collected by different teams of neuroscience and mental health researchers over the past 30 years. All this data was collected using magnetic resonance imaging (MRI), a non-invasive imaging technique that allows scientists to obtain 3D images of the brain and infer properties of white matter connections.
The researchers collectively analyzed the results of several studies, looking at schizophrenia and BD both individually and together, all while also accounting for differences in age and sex. This allowed them to identify brain regions that appear to be similarly affected in patients with either of the two disorders.
Most notably, they observed shared white matter alterations in a region called the corpus callosum. This is a brain structure that connects the brain's left and right hemispheres.
This alteration was observed across the entire psychosis spectrum, rather than being limited to a single diagnosis.
Importantly, these findings remained significant (and in some cases became clearer) after accounting for age and sex, suggesting they are unlikely to be explained simply by illness duration or aging. This supports the idea that disruptions in brain connectivity may represent a core biological feature of psychosis.
The results of this recent meta-analysis pinpoint a candidate biomarker that appears to characterize both schizophrenia and BD.
Giuseppe Pierpaolo Merola et al, A systematic review and meta-analysis of transdiagnostic impairments in white matter integrity across the psychosis continuum, Nature Mental Health (2026). DOI: 10.1038/s44220-025-00573-6.
yesterday
Dr. Krishna Kumari Challa
Why AI may overcomplicate answers: Humans and LLMs show 'addition bias,' often choosing extra steps over subtraction

When making decisions and judgments, humans can fall into common "traps," known as cognitive biases. A cognitive bias is essentially the tendency to process information in a specific way or follow a systematic pattern. One widely documented cognitive bias is the so-called addition bias, the tendency of people to prefer solving problems by adding elements as opposed to removing them, even if subtraction would be simpler and more efficient. One example of this is adding more paragraphs or explanations to improve an essay or report, even if removing unnecessary sections would be more effective.
Researchers recently carried out a study aimed at investigating whether artificial intelligence (AI) agents, particularly the computational models underpinning the functioning of ChatGPT, also exhibit this tendency when answering user queries. Their findings, published in Communications Psychology, suggest that these models can inherit the addition bias from human-written texts that they are trained on.
Generative artificial intelligences, particularly large language models (LLMs), increasingly influence human decision-making, making it essential to understand how cognitive biases are reproduced or amplified in these systems
Building on evidence of the human 'addition bias'—a preference for additive over subtractive problem-solving strategies—this research compared humans with GPT-4 and GPT-4o in spatial and linguistic tasks.
Part 1
yesterday
Dr. Krishna Kumari Challa
Researchers carried out two studies that compared the responses of human participants to two distinct LLMs, namely GPT-4 and GPT-4o, respectively.
The human participants and LLMs were tested on two different types of tasks: spatial and linguistic tasks. Spatial tasks entail the arrangement of shapes or structures in specific ways, while linguistic tasks require respondents to choose or generate specific texts following a set of instructions.
They found that both the human participants and the LLMs they examined exhibited an addition bias. However, this bias was less pronounced in humans and more pronounced in LLMs on tasks where subtracting information was clearly the more efficient strategy to tackle a problem.
Humans made fewer additive choices when subtraction was more efficient than addition (compared to when both were equally efficient), whereas GPT-4's output showed the opposite pattern.
Lydia Uhler et al, Influence of solution efficiency and valence of instruction on additive and subtractive solution strategies in humans, GPT-4, and GPT-4o, Communications Psychology (2026). DOI: 10.1038/s44271-026-00403-0.
part 2
yesterday
Dr. Krishna Kumari Challa
Some glaciers can suddenly surge forward—with dangerous consequences
A small fraction of glaciers undergo sudden surges, advancing rapidly for months or years due to meltwater accumulation beneath the ice, which reduces friction. These surges, affecting about 1% of glaciers but 16% of global glacier area, can accelerate ice loss and create hazards such as floods and infrastructure damage. Climate change is altering surge frequency and unpredictability worldwide.
https://theconversation.com/some-glaciers-can-suddenly-surge-forwar...
yesterday
Dr. Krishna Kumari Challa
India plans AI 'data city' on staggering scale
India is developing a large-scale "data city" in Visakhapatnam to accelerate its AI infrastructure, supported by major investments exceeding $175 billion, including projects from Google and other global firms. The initiative aims to establish a comprehensive AI ecosystem, targeting six gigawatts of data center capacity, and leverages strategic incentives and infrastructure to attract technology companies.
https://techxplore.com/news/2026-02-india-ai-city-staggering-scale....
yesterday
Dr. Krishna Kumari Challa
How one genome creates two distinct fungal bodies
Creatures that can change from one form to another ?
Yes, Nature, too, has its shapeshifters, such as dimorphic fungi. While scientists have known for some time that they can reversibly transition between yeast and mycelium forms, a paper recently published in the journal Nature Communications explains how.
Some fungi, such as members of the Mucorales order, can live as yeasts, tiny single-celled organisms, or as mycelium, multicellular branching filaments. Triggers for the morphological switch include oxygen levels and glucose concentrations. How can a single genome encode two different body plans and could switch between them?
To find out, scientists grew the fungus (Mucor lusitanicus) under oxygen-rich conditions to promote mycelial growth, and under low-oxygen, high-carbon-dioxide conditions to induce the yeast form. Once the fungus had changed shape, the team collected samples and examined the active genetic instructions, specifically the RNA, to see which were being used in each form.
The team found that instead of using the same genes for both forms, the fungus uses paralogs. These are closely related genes that share a common ancestor and arise when a gene is duplicated within a single genome.
In total, they found 490 dimorphic gene families. Although each twin pair has similar functions, there is a specific version for yeast and one for mycelium. For example, a gene responsible for iron absorption in the yeast form has a nearly identical counterpart that performs the same function in the mycelium form.
They are organized in a very elegant way in the genome. The scientists discovered that two related genes are positioned back to back on the DNA and share a bidirectional promoter. These regulate gene expression and so act like control switches. It means the promoters can easily turn one off and the other on without getting them mixed up.
At the heart of the operation, according to the researchers, are two master regulator genes, dkl and dfl. When the team deleted them, the fungus could no longer control its switches and lost its ability to change shape.
The findings identify an evolutionary mechanism that integrates and optimizes the genetic information required for two distinct life forms within a single organism.
One of the most exciting aspects of this research is the potential for new antifungal treatments. Knowing how a fungus switches to its invasive mycelial form gives scientists a clear target to stop the transformation and therefore the spread of fungal infections.
Ghizlane Tahiri et al, Coordinated gene family evolution shapes the genome of dimorphic Mucorales, Nature Communications (2026). DOI: 10.1038/s41467-026-68866-7
yesterday
Dr. Krishna Kumari Challa
Deer inhibit trees but raise plant diversity, 18-year study reveals
At high densities, white-tailed deer inhibit growth of trees but increase the overall diversity of smaller plant and weed species, according to a long-term study published recently.
High densities of white-tailed deer suppress tree regeneration and reduce tree presence in both above-ground vegetation and the soil seedbank, limiting natural forest regrowth. However, deer browsing increases the diversity and evenness of smaller plant and weed species by preventing dominance by a few species. Active management is likely required for successful reforestation in areas with abundant deer.
A. Sophie Westbrook et al, Deer impact seedbanks and plant communities over 18 years of post-agricultural succession, PLOS One (2025). DOI: 10.1371/journal.pone.0339466
yesterday
Dr. Krishna Kumari Challa
Deep-sea fish larvae rewrite the rules of how eyes can be built
Deep-sea fish larvae possess unique hybrid photoreceptor cells that combine structural features of rods with the molecular machinery of cones, enabling enhanced vision in the dim twilight zone. Unlike the typical vertebrate pattern where cones precede rods, these larvae use rod-like cones early in development, with some species retaining them into adulthood. This challenges established models of vertebrate retinal development.
https://theconversation.com/deep-sea-fish-larvae-rewrite-the-rules-...
yesterday
Dr. Krishna Kumari Challa
Injured birds seeking medical help
Injured seabird desperately pecks at hospital door for help
An injured seabird sought help by pecking at the door of an emergency room at a hospital in Germany until medical staff noticed it and called firefighters to help with its rescue.
The cormorant, a shiny black waterbird, had a triple fishing hook stuck in its beak when it made its presence known at the glass door of the Klinikum Links der Weser hospital in the northern city of Bremen on Sunday.
In a joint effort, medical staff and firefighters removed the fishhook and treated the wound, the Bremen firefighter department said in a statement. The bird was later released back into nature on the grounds of the hospital park.
"When an injured cormorant does approach humans, it is usually an animal in extreme distress that has lost its natural shyness," the statement said.
A cormorant is a large bird with a long neck, wedge-shaped head and a distinctive sharp beak with a hooked tip. A fishhook in the bird's beak would be extremely dangerous for the animal. Infections, pain and even starvation are possible, the firefighter department said.
Source: News agencies
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yesterday
Dr. Krishna Kumari Challa
Want a tall, smart child? How IVF tests are selling a dream
Genetic tests marketed to IVF parents claim to predict traits like height and intelligence using polygenic risk scores, but these predictions are highly uncertain and offer minimal benefit—typically only a few IQ points or centimeters in height. Environmental and lifestyle factors play a much larger role in child development, and using such tests poses ethical, psychological, and medical risks without proven advantages.
https://theconversation.com/want-a-tall-smart-child-how-ivf-tests-a...
yesterday
Dr. Krishna Kumari Challa
Yes, men have a biological clock too. But it's not just age that affects male fertility
Male fertility declines with age, with sperm count, motility, morphology, and semen volume decreasing from the early 20s, and genetic damage in sperm increasing, raising miscarriage and birth defect risks. Environmental and lifestyle factors, such as oxidative stress, toxins, smoking, obesity, and certain medical conditions, also impact male fertility. New guidelines recommend simultaneous fertility assessment for both partners.
https://theconversation.com/yes-men-have-a-biological-clock-too-but...
yesterday
Dr. Krishna Kumari Challa
The Universe throws surprises at us all the time!
Bacterial strain from 5,000-year-old cave ice shows resistance against 10 modern antibiotics
Bacteria have evolved to adapt to all of Earth's most extreme conditions, from scorching heat to temperatures well below zero. Ice caves are just one of the environments hosting a variety of microorganisms that represent a source of genetic diversity that has not yet been studied extensively. Now, researchers tested antibiotic resistance profiles of a bacterial strain that until recently was hidden in a 5,000-year-old layer of ice of an underground ice cave—and found it could be an opportunity for developing new strategies to prevent the rise of antibiotic resistance and study how resistance naturally evolves and spreads. They reported their discovery in Frontiers in Microbiology.
The Psychrobacter SC65A.3 bacterial strain isolated from Scarisoara Ice Cave, despite its ancient origin, shows resistance to multiple modern antibiotics and carries over 100 resistance-related genes. But it can also inhibit the growth of several major antibiotic-resistant 'superbugs' and showed important enzymatic activities with important biotechnological potential.
Psychrobacter SC65A.3 is a strain of the genus Psychrobacter, which are bacteria adapted to cold environments. Some species can cause infections in humans or animals. Psychrobacter bacteria have biotechnological potential, but the antibiotic resistance profiles of these bacteria are largely unknown.
Studying microbes such as Psychrobacter SC65A.3 retrieved from millennia-old cave ice deposits reveals how antibiotic resistance evolved naturally in the environment, "long before modern antibiotics were ever used".
The team drilled a 25-meter ice core from the area of the cave known as the Great Hall, representing a 13,000-year timeline. To avoid contamination, the ice fragments taken from the core were placed in sterile bags and kept frozen on their way back to the lab. There, the researchers isolated various bacterial strains and sequenced their genome to determine which genes allow the strain to survive in low temperatures and which confer antimicrobial resistance and activity.
They tested for resistance of the SC65A strain against 28 antibiotics from 10 classes that are routinely used to or reserved for treating bacterial infections, including antibiotics that have previously been identified to possess resistance genes or mutations that give them the ability to resist drug effects. This way, they could test whether predicted mechanisms translated into measurable resistance.
The 10 antibiotics they found resistance to are widely used in oral and injectable therapies used to treat a range of serious bacterial infections in clinical practice.
Diseases such as tuberculosis, colitis, and UTIs can be treated with some of the antibiotics that the researchers found resistance to, including rifampicin, vancomycin, and ciprofloxacin.
Part 1
16 hours ago
Dr. Krishna Kumari Challa
SC65A.3 is the first Psychrobacter strain for which resistance to certain antibiotics—including trimethoprim, clindamycin, and metronidazole—was found. Those antibiotics are used to treat UTIs, infections of lungs, skin, or blood, and the reproductive system. SC65A.3's resistance profile suggests that strains capable of surviving in cold environments could act as reservoirs of resistance genes, which are specific DNA sequences that help them survive exposure to drugs.
Bacterial strains like the one examined here hold both a threat and a promise. "If melting ice releases these microbes, these genes could spread to modern bacteria, adding to the global challenge of antibiotic resistance.
On the other hand, they produce unique enzymes and antimicrobial compounds that could inspire new antibiotics, industrial enzymes, and other biotechnological innovations.
In the Psychrobacter SC65A.3 genome, the researchers found almost 600 genes with unknown functions, suggesting a yet untapped source for discovering novel biological mechanisms. Analysis of the genome also revealed 11 genes that are potentially able to kill or stop the growth of other bacteria, fungi, and viruses.
These ancient bacteria are essential for science and medicine.
First genome sequence and functional profiling of a Psychrobacter SC65A.3 preserved in 5,000-year-old cave ice: frominsights into ancient resistome, to antimicrobial potential and enzymatic activities, Frontiers in Microbiology (2026). DOI: 10.3389/fmicb.2025.1713017
Part 2
16 hours ago
Dr. Krishna Kumari Challa
Beyond 'survival' of fittest: Evolution works in teams
Natural selection operates at multiple levels of biological organization, not just at the individual level. Empirical evidence from diverse species demonstrates that traits can be favoured or suppressed through both individual and group-level selection, sometimes in opposing directions. Recognizing multilevel selection provides a more comprehensive understanding of evolutionary processes and has practical implications in fields such as medicine and agriculture.
The common view of natural selection is based solely on the individual: A trait allows an organism to out-compete its rivals and is thus passed down to its offspring. To suggest otherwise can provoke the ire of certain segments of the scientific community.
But a bibliometric review of 280 scientific studies shows that natural selection can occur on multiple levels of biological organization simultaneously, and not just in social species.
The idea of looking at selection at multiple levels is to measure whether a trait is adaptive for individuals within a group. And does the frequency or existence of that trait within a group change the way the group functions in comparison with other groups?
The studies examined by the researchers spanned more than a century, covering everything from viruses to human beings. All attempted to account for multilevel selection (MLS), which provides a broader view of natural selection than individual benefit.
Why does multilevel selection remain controversial? Scientific culture. Since the 1960s, key scientists have observed that claims of group benefits weren't subject to rigorous measurement and shouldn't be taken seriously. Some scientists openly banned discussion of group selection in their classrooms, calling it naïve; others claimed that it was exceedingly rare or another term for kin selection.
If you measure the average increase in the frequency of a trait over generations and then say it's favoured by natural selection, you're not wrong
But what's the mechanism for the slow increase in that trait over here and the rapid increase over there?
If you had looked at different levels, you might see that group competition is more important in one place, or cooperation within groups in another.
Part 1
10 hours ago
Dr. Krishna Kumari Challa
Imagine that there are two human tribes. In one, members are solely focused on their individual success. In the other, members are willing to sacrifice themselves for the good of the whole; however, this altruism may cost them time and resources that they could expend on their own children and personal survival.
Which tribe is more likely to survive a crisis, such as an attack from another group? The second.
Paradoxically, the willingness for an individual to sacrifice for the group can lead to better survival outcomes. That doesn't mean that everyone in a group will become self-sacrificing, but that groups with self-sacrificing individuals may have a survival advantage.
To take a broader view, individuals not only live in communities but are communities. We are composed of trillions of cells, which comprise our tissues and organs, along with the bacteria in our microbiome and the viruses that afflict us. We live in families, neighborhoods, and countries, as well as ecosystems that bring us into contact with other species.
Every single one of these systems can change over time in response to stimuli, shifting and adapting in response to one another. Groupings can also influence individual success; consider, for example, the case of a family struggling with systemic poverty, or the impact of a troubled neighborhood on the individuals within it.Cancer is another interesting example, as are viral illnesses. On one hand, cancer cells no longer cooperate with the rest of the body, subverting the communal good for their individual benefit. But the situation isn't so cut-and-dry.
"In some cases, cancer cells act as a cooperative group in their own right; the ways they spread are strategic. You can also get competition between diseases for host resources
But what happens within a host is not the whole story; the host's environment is critical, too. If a communicable disease exists in a host population with frequent and predictable contacts, rapid growth with damage to a host may evolve, because this will not stop the host from passing it on.
However, such diseases would soon die out in populations of more isolated individuals; in the second scenario, more benign versions would have the advantage, because longer surviving hosts would give the host—and its virus or bacteria—time to find another host. Thus, selection within hosts may favor disease organisms that reproduce faster, but selection between the groups of disease organisms defined by each host may be in the exact opposite direction.
Multilevel selection complicates the picture because you have to consider all the places where selection could be occurring, and it's possible that selection on one level is headed in a different direction than selection on another level
Part 2
10 hours ago
Dr. Krishna Kumari Challa
There is a real benefit to having a fuller picture of natural selection, particularly in medicine and agriculture. The role that widespread antibiotic use plays in shaping a bacterial arms race is a well-known example.
Another example involves chickens. In one famous study, the agricultural scientist William Muir focused on selecting for egg productivity of hens housed in battery cages. In one experiment, he selected the most productive hen within each cage to breed the next generation of hens (within-group selection). The result? A hyper-aggressive strain of hens that achieved their productivity at the expense of others, resulting in a decline in productivity at the cage level.
In a parallel experiment, Muir selected the most productive cages and used all the hens within the cages to breed the next generation of hens (group-level selection). The result? A docile strain of hens that didn't interfere with each other and achieved a 160% increase in productivity at the cage level in five generations. Based on this and other experiments, group-level selection has become standard practice in animal and plant breeding.
We can also apply the theory to ourselves, keeping Muir's chicken experiments in mind: Are we creating situations that reward competitive or even selfish behaviors? Consider a classroom that grades students on how many questions they ask, penalizing those who are quiet or slow to raise their hands. In that case, the class has selected for rapid responders rather than innovators or deep thinkers
Abundant empirical evidence of multilevel selection revealed by a bibliometric review, Frontiers in Ecology and Evolution (2026). doi.org/10.3389/fevo.2026.1752597
Part 3
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10 hours ago
Dr. Krishna Kumari Challa
Not all humans are 'super-scary' to wildlife, animal behaviour study suggests
Humans have climbed to the top of the food chain by skillfully hunting, trapping, and fishing for other animals at scales that far exceed other predators, altering how the animals behave and earning the tag of a "super-predator." But a new study led by the Center for Ecological Sciences, Indian Institute of Science (IISc), suggests that there is a bit more nuance to this idea. While animals clearly respond with fear to humans who hunt or kill, they are far less consistent in how they react to non-lethal human presence.
Zoos and eco-tourist spots? YES!
Wild animals show strong fear responses to lethal human activities like hunting, becoming more vigilant and reducing foraging, but react less consistently to non-lethal human presence. Human structures can sometimes decrease animal vigilance by providing perceived refuges. These behavioural changes influence survival, reproduction, and ecosystem dynamics, highlighting the need for nuanced conservation strategies.
A comprehensive meta-analysis, published in Ecology Letters, analyzes three decades of research on how wild animals change their behavior in response to different types of human interactions. The study examined behavioural shifts in foraging, vigilance, and movement across species and ecosystems to look into whether humans are always super-scary.
"The short answer is: no, not always"
Researchers found strong evidence that lethal humans such as hunters and fishers are indeed perceived as threatening. Animals in areas exposed to lethal humans tend to be more vigilant and spend less time foraging. In contrast, responses to non-lethal humans such as tourists or researchers are weaker and more variable.
The study's findings broadly support the "risk allocation hypothesis," which suggests that animals adjust their behaviour based on how intense and predictable a threat is. When danger is high and consistent, animals stay cautious. When risk is low or predictable, they can afford to relax.
Beyond individual behaviour, the researchers point to a bigger picture. Changes in fear and behaviour can cascade through ecosystems, altering grazing, predation, and ecological balance.
Shawn Dsouza et al, Are Human Super‐Predators Always Super‐Scary? A Meta‐Analysis of Wild Animal Behavioural Responses to Human Interactions, Ecology Letters (2025). DOI: 10.1111/ele.70287
10 hours ago
Dr. Krishna Kumari Challa
Rescuing Antibiotics?
10 hours ago