Hawking and Kerr black hole theories confirmed by gravitational wave

Scientists have confirmed two long-standing theories relating to black holes—thanks to the detection of the most clearly recorded gravitational wave signal to date.

Ten years after detecting the first gravitational wave, the LIGO-Virgo-KAGRA Collaboration has (10 Sep) announced the detection of GW250114—a ripple in spacetime which offers unprecedented insights into the nature of black holes and the fundamental laws of physics.

The study confirms Professor Stephen Hawking's 1971 prediction that when black holes collide, the total event horizon area of the resulting black hole is bigger than the sum of individual black holes—it cannot shrink.

Research also confirmed the Kerr nature of black holes—a set of equations developed in 1963 by New Zealand mathematician Roy Kerr elegantly explaining what space and time look like near a spinning black hole. The Kerr metric predicts effects such as space being 'dragged' around and light looping to make multiple copies of objects.

Publishing their findings in Physical Review Letters, the international group of researchers note that GW250114 was detected with a signal-to-noise ratio of 80. This clarity enabled precise tests of general relativity and black hole thermodynamics.

GW250114: testing Hawking's area law and the Kerr nature of black holes, Physical Review Letters (2025). DOI: 10.1103/kw5g-d732

'Potential biosignatures' found in ancient Mars lake

A new study suggests a habitable past and signs of ancient microbial processes on Mars. Led by NASA and featuring key analysis from Imperial College London, the work has uncovered a range of minerals and organic matter in Martian rocks that point to an ancient history of habitable conditions and potential biological processes on the Red Planet.

This is a very exciting discovery of a potential biosignature but it does not mean we have discovered life on Mars. We now need to analyze this rock sample on Earth to truly confirm if biological processes were involved or not.

While driving through the valley, called Neretva Vallis, Perseverance came across a thick succession of fine-grained mudstones and muddy conglomerates. Here, it conducted a detailed analysis of these rocks, using instruments such as the Planetary Instrument for X-ray Lithochemistry (PIXL) and Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals (SHERLOC).

By mapping the types and distributions of different sedimentary rocks, researchers were able to reconstruct the environment in which these mudstones were deposited.

Their analysis revealed a range of sedimentary structures and textures indicative of lake margin and lake bed environments, including a composition rich in minerals like silica and clays—the opposite to a river scenario, where fast-moving water would carry these tiny particles away.

This pointed to a surprising conclusion: they had found lake deposits in the bottom of a river valley.

The finding may suggest a period in the history of Jezero Crater where the valley itself was flooded, giving rise to this potentially habitable lake.

With the lake habitat scenario pinned down, the Perseverance science team turned their attention to the mudstones themselves. It was inside these rocks that they discovered a group of tiny nodules and reaction fronts, with chemical analysis revealing that these millimeter-scale structures are highly enriched in iron-phosphate and iron-sulfide minerals (likely vivianite and greigite).

These appear to have formed through redox reactions involving organic carbon, a process that could have been driven by either abiotic or—interestingly—biological chemistry. Importantly, this sets the stage for everything that happened next: the formation of this specific type of oxidized, iron- and phosphorus-rich sediment was the essential prerequisite for creating the ingredients for subsequent reactions.

Since these ingredients mirror by-products of microbial metabolism seen on Earth, it can be considered a compelling potential biosignature, raising the possibility that there was once microbial life on Mars.

Ultimately, the only way for the true origin of these structures to be determined is by returning the samples to Earth, a possibility that rests on when future missions will manage to successfully collect the samples from Mars' surface.

Joel Hurowitz, Redox-driven mineral and organic associations in Jezero Crater, Mars, Nature (2025). DOI: 10.1038/s41586-025-09413-0. www.nature.com/articles/s41586-025-09413-0

Climate change is driving fish stocks from countries' waters to the high seas, study finds

Fish and other marine organisms, though deeply affected by human activities, don't respect human borders. The ranges of many commercially important species in fact straddle the borders of countries' exclusive economic zones (EEZs) and international waters, known as the high seas. This arrangement, which makes fisheries management difficult, is set to get even more complicated as climate change continues to heat up the ocean, a new study says.

The study, published July 30 in the journal Science Advances, found that more than half of the world's straddling stocks will shift across the maritime borders between EEZs and the high seas by 2050. Most of these shifts will be into the high seas, where fisheries management is much more challenging and stocks are more likely to be overexploited.

Juliano Palacios-Abrantes et al, Climate change drives shifts in straddling fish stocks in the world's ocean, Science Advances (2025). DOI: 10.1126/sciadv.adq5976

Kamal Azmi et al, Putting Regional Fisheries Management Organisations' Climate Change House in Order, Fish and Fisheries (2025). DOI: 10.1111/faf.70015

Maternal gut microbiome composition may be linked to preterm births

Researchers have found that the presence of certain bacteria in the maternal gut microbiome during early pregnancy is linked to a higher risk of preterm birth. Published in the journal Cell Host & Microbe on September 10, the study reports that one particular species, Clostridium innocuum (C. innocuum), contains a gene that can degrade estradiol—an important pregnancy hormone.

This study suggests that for pregnant women or women preparing to become pregnant, it may be important to monitor their gut microbiome to prevent potential adverse pregnancy outcomes.

The researchers used samples and data from two large pregnancy cohorts—the Tongji-Huaxi-Shuangliu Birth cohort from southwest China and the Westlake Precision Birth cohort from southeast China.
For the first cohort, the team collected stool samples from 4,286 participants in early pregnancy, at an average of 10.4 gestational weeks. For the second cohort, they collected stool samples from 1,027 participants in mid-pregnancy, or around 26 gestational weeks. They also collected blood samples from all participants, which were used to measure human genetic variations and hormone metabolism.

After working with the first cohort, the researchers were able to establish a comprehensive database containing rRNA-based microbial genera data, metagenome-based species data, and phenotype data such as preterm delivery status.

They used several statistical models to screen the annotated gut microbial genera and species and their relationship to preterm birth status or gestational duration .Through that work, they identified 11 genera and 1 species that had a statistically significant link.

The results, which were validated with the second cohort, showed that bacterial species C. innocuum—a small, rod-shaped bacteria—had the strongest connection to preterm birth. Further study of C. innocuum revealed that this species makes an enzyme that degrades estradiol—a form of estrogen that plays a pivotal role during pregnancy.

Estradiol regulates critical pathways that sustain pregnancy and initiate the process of childbirth.

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The researchers propose that dysregulated estradiol levels induced by a high prevalence of C. innocuum could be the mechanism that links the gut microbiome to preterm birth.
The researchers note that because their study was based on two China-based cohorts with a relatively low prevalence of preterm birth, the findings may not be generalizable to other populations and should be authenticated by more work with them.

In the future, they hope to further elucidate the molecular mechanisms by which C. innocuum modulates preterm birth risk and potentially identify optimal intervention strategies to mitigate the bacteria's impact on pregnancy. They also seek to characterize the interaction between C. innocuum and host estrogen metabolism more generally, beyond pregnancy.

Maternal gut microbiome during early pregnancy predicts preterm birth, Cell Host & Microbe (2025). DOI: 10.1016/j.chom.2025.08.004. www.cell.com/cell-host-microbe … 1931-3128(25)00330-0

Part 2

Donor-egg births may carry more risks

More women than ever are carrying babies conceived with someone else's egg—but few are told that this might carry greater health risks.

Pregnancies involving an embryo that doesn't share the pregnant woman's DNA are becoming more common. For many, it's a path to parenthood that would otherwise be closed.
But emerging evidence suggests that these pregnancies may come with higher rates of complications, including preeclampsia, gestational diabetes and preterm birth, and that women are often not given the full picture before treatment.

As the fertility industry expands and diversifies, it's time to ask whether patients are being adequately informed about the risks of carrying another woman's egg—and whether more caution is needed in how these options are presented.

There are three situations in which a woman may carry another woman's egg in her uterus.

The most common is when a woman cannot produce her own eggs but has a functioning uterus. In this case, donor eggs and in-vitro fertilization (IVF) offer the only route to pregnancy.

The other two situations involve fertile women carrying a donated egg on behalf of someone else. This happens in cases of gestational surrogacy, where a surrogate carries a baby genetically unrelated to her, or in reciprocal IVF, also known as ROPA or co-IVF. In the latter, one woman in a same-sex couple (or a trans man) donates her egg to her partner, so that both have a biological connection to the child.

In IVF, fertilization occurs outside the body and the resulting embryo is transferred into the uterus. But what happens when the egg in the uterus has no genetic similarity to the woman carrying it? Could this cause complications for her or the baby?

To answer that question, we need to compare outcomes in these situations to pregnancies where the egg shares approximately 50% of the mother's DNA, either through natural conception or own-egg IVF. Early evidence suggests that having someone else's egg in the uterus is associated with a higher risk of obstetric complications, including preeclampsia, gestational diabetes and preterm birth.

There are three key comparisons to make. First, donor-egg IVF v own-egg IVF. For infertile women using donor eggs, the most relevant comparison is IVF with their own eggs.
Second, gestational v traditional surrogacy. In gestational surrogacy, the surrogate carries a donor egg, while in traditional surrogacy, she uses her own. Outcomes can also be compared with the surrogate's previous natural pregnancies.

Third, reciprocal IVF v own-egg IVF. In same-sex couples, reciprocal IVF can be compared to own-egg IVF to assess risks.
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A review of 11 studies comparing donor-egg IVF to own-egg IVF found that donor-egg pregnancies had significantly higher rates of hypertensive disorders in the mother, as well as preterm birth and babies that were small for their gestational age.

A separate review focusing on preeclampsia in singleton IVF pregnancies found the condition occurred in 11.2% of donor-egg pregnancies, compared to 3.9% of own-egg pregnancies.

For women who can only become pregnant using a donor egg, these risks may be worth accepting. But it's important that women are made aware of the potential complications, especially if carrying twins, which further increases risks.

Women deserve full, unbiased information about the risks. That includes knowing that carrying someone else's egg may increase the likelihood of pregnancy complications. They can then make informed decisions about whether the potential benefits outweigh the risks.

Phoebe Barry et al, The outcomes of surrogate pregnancy using a donor egg compared to the surrogate's egg: a systematic review, Preprints (2025). DOI: 10.22541/au.174919886.60741282/v1

Part2

DNA cassette tapes could solve global data storage problems

Our increasingly digitized world has a data storage problem. Hard drives and other storage media are reaching their limits, and we are creating data faster than we can store it. Fortunately, we don't have to look too far for a solution, because nature already has a powerful storage medium with DNA (deoxyribonucleic acid). It is this genetic material that researchers are using to create DNA storage cassettes.

DNA is the ultimate data storage solution because it is compact, dense and durable. It can hold an enormous amount of information in a microscopic space and preserve that data for thousands of years without needing electricity. Theoretically, the DNA in a single human cell has a capacity of approximately 3.2 gigabytes, which equates to roughly 6,000 books, 1,000 pieces of music or two movies.

Scientists have known about DNA's potential as a storage solution for a long time, but the challenge up until now has been to create a viable system that we can use. In a new study published in the journal Science Advances, researchers describe how they made a DNA cassette similar to cassette tapes that were staples in personal and car stereos in the 1980s.

The team first created the physical tape from a polyester-nylon blend. Then they printed barcode patterns on it to make millions of tiny, separate sections, similar to folders on a computer. This lets the system find the exact spot where the data is stored. Accessing information has been one of the problems of previous DNA storage techniques.
To store a file, digital data is first translated into a DNA sequence. The four bases, or building blocks of DNA (A, G, C, and T) act as a code, similar to the zeroes and ones that computers use. The researchers also coated the tape with a protective crystalline layer to protect the DNA bonds from breaking down.
Finally, they proved the system works by converting a digital image into DNA, then successfully and quickly retrieving it from the tape.

DNA cassette tape provides a strategy for fast, compact, large-scale DNA-based cold (infrequently accessed) or warm (needed on demand) data storage,  wrote the scientists in their paper.

Jiankai Li et al, A compact cassette tape for DNA-based data storage, Science Advances (2025). DOI: 10.1126/sciadv.ady3406

Medications leave lasting mark on gut microbiome, even years after use

Medications taken years ago can continue to shape the human gut microbiome, according to a large-scale study.

Analyzing stool samples and prescription records from over 2,500 Estonian Biobank participants in the Estonian Microbiome cohort, researchers found that the majority of drugs studied were linked to microbiome changes, with a substantial number of them also showing long-term effects detectable years after patients stopped taking them.

The impact was not limited to antibiotics: antidepressants, beta-blockers, proton pump inhibitors, and benzodiazepines all left microbial "fingerprints."

Most microbiome studies only consider current medications, but our results show that past drug use can be just as important as it is a surprisingly strong factor in explaining individual microbiome differences. 

This highlights that it is critical to account for drug usage history when studying links between the microbiome and disease. The research is published in the journal mSystems.

Interestingly, benzodiazepines—commonly prescribed for anxiety—had microbiome effects comparable to broad-spectrum antibiotics. The results also show that drugs from the same class that might be used for the same condition, e.g. diazepam and alprazolam, may differ in how much they disrupt the microbiome.

Follow-up samples from a subset of participants confirmed that starting or stopping certain drugs caused predictable microbial shifts, suggesting causal effects. Despite the small sample size of the second time-point analysis, the authors were able to verify long-term effects of proton pump inhibitors, selective serotonin reuptake inhibitors and antibiotics, such as penicillins in combination and macrolides.

Oliver Aasmets et al, A hidden confounder for microbiome studies: medications used years before sample collection, mSystems (2025). DOI: 10.1128/msystems.00541-25

Breathlessness increases long-term mortality risk, finds a study in Malawi

Research led by Liverpool School of Tropical Medicine and the Malawi-Liverpool-Wellcome Program shows that over half of hospital patients with breathlessness had died within a year of admission (51%), as opposed to just 26% of those without the symptom.

Most of these patients had more than one condition that caused breathlessness, including pneumonia, anemia, heart failure and TB.

The findings demonstrate the importance of integrated, patient-centered care, researchers say, to tackle the burden of high mortality for people with breathlessness, particularly in low-income countries. The work appears in Thorax.

Most of these patients live with more than one condition at the same time, which the researchers found to be a factor linked to higher mortality, such as those with TB or pneumonia. This suggests that treating diseases in isolation is not enough, and health care models that have traditionally focused on single presenting conditions may overlook important concurrent diseases.

Acute breathlessness as a cause of hospitalisation in Malawi: a prospective, patient-centred study to evaluate causes and outcomes, Thorax (2025). DOI: 10.1136/thorax-2025-223623

A pathological partnership between Salmonella and yeast in the gut

Researchers have found that a common gut yeast, Candida albicans, can help Salmonella typhimurium take hold in the intestine and spread through the body. When interacting, a Salmonella protein called SopB prompts the yeast to release arginine, which turns on Salmonella's invasion machinery and quiets the body's inflammation signals.

Gut microbes shape human health across colonization resistance, immune training, digestion, and signaling that reaches distant organs. Bacteria dominate both abundance and research attention, while roles for viruses and fungi remain less defined.

Altered mycobiome composition appears in multiple gastrointestinal diseases, and integration of fungi into gut ecology and into interactions with commensal and pathogenic bacteria remains largely unknown.

Non-typhoidal Salmonella ranks among the best-studied enteric pathogens, infecting an estimated 100 million people each year. Healthy individuals typically experience localized inflammatory diarrhea, while immunocompromised patients face risks of spread to peripheral organs.

Establishing gut colonization requires competition with resident microorganisms, and commensal fungi occur across tested mammalian species, yet mycobiome contributions during enteric infection remain largely unexplored.

Candida albicans is a frequent colonizer of human mucosal surfaces, present in the gut of more than 60% of healthy humans. Usual behavior is commensal, with pathogenic potential particularly in immunocompromised hosts. A key virulence trait is morphology switching from yeast to epithelium-penetrating hyphae.

Associations with inflammatory bowel disease, specifically Crohn's disease, have been reported. C. albicans cannot induce gut inflammation and has been shown to exacerbate it. Both Salmonella and C. albicans thrive under inflammatory gut conditions, and C. albicans likely resides in the gut of many patients at the time Salmonella infection occurs.

In the study, "Commensal yeast promotes Salmonella Typhimurium virulence," published in Nature, researchers investigated cross-kingdom interactions to determine how Candida albicans influences Salmonella colonization, systemic dissemination, and host inflammatory responses.

In the experiments conducted in mice, Candida in the gut led to higher Salmonella loads in the large intestine and more bacteria reaching the spleen and liver, with co-infected mice losing more weight. Candida also boosted Salmonella entry into human colon cell lines. Gene readouts showed Salmonella's invasion machinery switched on near Candida.

Co-cultures contained millimolar arginine, and adding L-arginine alone increased invasion in a dose-dependent way, while an arginine-transporter mutant did not respond to Candida. Candida lacking arginine production also failed to boost Salmonella invasion or gut colonization, and an ARG4 revertant restored the effect.

Researchers conclude that C. albicans colonization represents a susceptibility factor for Salmonella infection, with arginine acting as a pivotal metabolite connecting fungus, bacterium, and host. Findings point to SopB-driven arginine production in Candida that boosts Salmonella's invasion program while softening host inflammatory signals.

 Kanchan Jaswal et al, Commensal yeast promotes Salmonella Typhimurium virulence, Nature (2025). DOI: 10.1038/s41586-025-09415-y

The sound of crying babies makes our faces hotter, according to new research

Hearing a baby cry can trigger a range of responses in adults, such as sympathy, anxiety and a strong urge to help. However, new research suggests that a deeper physical reaction is also occurring. A baby's cry, particularly if it is in pain or distress, makes our faces physically warmer.

Since they can't speak yet, babies cry to communicate their needs, whether they're in pain or want some attention. When a baby is in distress, they forcefully contract their ribcage, which produces high-pressure air that causes their vocal cords to vibrate chaotically. This produces complex disharmonious sounds known as nonlinear phenomena (NLP).

To study how adults respond to crying babies, scientists played 23 different recordings to 41 men and women with little to no experience with young infants. At the same time, a thermal infrared imaging camera measured subtle changes to their facial temperatures. A rise in temperature in this part of the body is governed by the autonomic nervous system, a network of nerves that controls unconscious processes such as breathing and digestion. After each cry, the participants rated whether the baby was in discomfort or in pain.

The study found that adults' facial temperatures change when they hear a baby cry, a clear sign that the autonomic nervous system has been activated. This suggests that people unconsciously pick up on acoustic features in a baby's cry. The higher the level of NLP (meaning a baby is in more pain or distress), the stronger and more in sync the listener's facial temperature became. In other words, as the cry grew louder, a person's face grew warmer. This physiological reaction was the same for both men and women.

Lény Lego et al, Nonlinear acoustic phenomena tune the adults' facial thermal response to baby cries with the cry amplitude envelope, Journal of the Royal Society Interface (2025). DOI: 10.1098/rsif.2025.0150

Scientists engineer plants to double carbon uptake ability and produce more seeds and lipids

Typically, plants rely on the Calvin-Benson-Bassham (CBB) cycle to convert carbon dioxide in the atmosphere to usable organic matter for growth. Although this cycle is the main pathway for carbon fixation in all plants on Earth, it is surprisingly inefficient—losing one third of carbon in the cycle when synthesizing the molecule acetyl–coenzyme A (CoA) to generate lipids, phytohormones, and metabolites. Plants also lose carbon during photorespiration, which limits their growth. This is largely due to the inefficiency of an enzyme called RuBisCO.

In efforts to increase carbon uptake and reduce carbon loss in plants to boost biomass and lipid production, scientists have experimented with ways to increase the efficiency of RuBisCO, overexpress CBB cycle enzymes, introduce carbon-concentrating mechanisms, and reduce photorespiration losses. But, a new study published in Science, focuses on a novel approach—creating an altogether new pathway for carbon uptake.

The researchers involved in the study introduced a synthetic CO₂ uptake cycle into the plant Arabidopsis thaliana. They refer to the engineered cycle as the malyl-CoA-glycerate (McG) cycle, which works in conjunction with the CBB cycle to create a dual-cycle CO₂ fixation system. The new cycle increases efficiency by using previously wasted carbon.

"In the McG cycle, one additional carbon is fixed when 3PG is the input, or no carbon is lost when glycolate is the input. In both cases, acetyl-CoA is produced more efficiently, which is expected to enhance the production of lipids and other important plant metabolites, including phytohormones," the authors write.

 Kuan-Jen Lu et al, Dual-cycle CO₂ fixation enhances growth and lipid synthesis in Arabidopsis thaliana, Science (2025). DOI: 10.1126/science.adp3528

Scientists discover how nanoplastics disrupt brain energy metabolism

Scientists have discovered how nanoplastics—even smaller than microplastics—disrupt energy metabolism in brain cells. Their findings may have implications for better understanding neurodegenerative diseases characterized by declining neurological or brain function, and even shed new light on issues with learning and memory.

The study has revealed the specific mechanism by which these tiny nanoplastics can interfere with energy production in the brain in an animal model. The findings, recently published in the Journal of Hazardous Materials: Plastics, provide fresh insights into the potential health risks posed by environmental plastics.

Polystyrene nanoplastics (PS-NPs) are produced when larger plastics break down in the environment. These particles have been detected in multiple organs in the body, including the brain, sparking growing concerns about their possible role in neurological disease.

The researchers focused on mitochondria, which are critical for producing the energy needed for brain function. Mitochondrial dysfunction is a well-known feature of neurodegenerative diseases such as Parkinson's and Alzheimer's, as well as normal aging.

By isolating mitochondria from brain cells, the researchers showed that exposure to PS-NPs specifically disrupted the "electron transport chain," a simplified term for the set of protein complexes that work together to help generate cellular energy in the form of ATP. While individual mitochondrial complexes I and II were not directly impaired, electron transfer between complexes I–III and II–III, as well as the activity of complex IV, was significantly inhibited.

The scientists found that electron transfer between complex I–III and complex II–III was potently inhibited at much lower concentrations, suggesting environmentally relevant exposures could also impair bioenergetic function over chronic timeframes.

Interestingly, the same broad effects were seen in synaptic mitochondria, which are essential for communication between brain cells. This suggests that nanoplastics could also interfere with synaptic plasticity, a process fundamental to learning and memory.

D.M. Seward et al, Polystyrene nanoplastics target electron transport chain complexes in brain mitochondria, Journal of Hazardous Materials: Plastics (2025). DOI: 10.1016/j.hazmp.2025.100003

The death of the dinosaurs reengineered Earth

Dinosaurs had such an immense impact on Earth that their sudden extinction led to wide-scale changes in landscapes—including the shape of rivers—and these changes are reflected in the geologic record, according to a new study.

Scientists have long recognized the stark difference in rock formations from just before dinosaurs went extinct to just after, but chalked it up to sea level rise, coincidence, or other abiotic reasons. But the new study shows that once dinosaurs were extinguished, forests were allowed to flourish, which had a strong impact on rivers.

Studying these rock layers, the researchers suggest that dinosaurs were likely enormous "ecosystem engineers," knocking down much of the available vegetation and keeping land between trees open and weedy. The result was rivers that spilled openly, without wide meanders, across landscapes. Once the dinosaurs perished, forests were allowed to flourish, helping stabilize sediment and corralling water into rivers with broad meanders.

Their results, published in the journal Communications Earth & Environment, demonstrate how rapidly the Earth can change in response to catastrophic events.

Very often when we're thinking about how life has changed through time and how environments change through time, it's usually that the climate changes and, therefore, it has a specific effect on life, or this mountain has grown and, therefore, it has a specific effect on life. It's rarely thought that life itself could actually alter the climate and the landscape. The arrow doesn't just go in one direction, the researchers say.

 Dinosaur extinction can explain continental facies shifts at the Cretaceous-Paleogene boundary, Communications Earth & Environment (2025). DOI: 10.1038/s43247-025-02673-8

Ants defend plants from herbivores, but can hinder pollination by bees

Around 4,000 plant species from different parts of the world secrete nectar outside their flowers, such as on their stems or leaves, through secretory glands known as extrafloral nectaries. Unlike floral nectar, extrafloral nectar does not attract pollinators; rather, it attracts insects that defend plants, such as ants. These insects feed on the sweet liquid and, in return, protect the plant from herbivores. However, this protection comes at a cost.

A study published in the Journal of Ecology points out that the presence of ants can reduce the frequency and duration that bees visit the flowers of plants with extrafloral nectaries.

Pollination is only impaired when extrafloral nectaries are close to the flowers. Plants with these glands in other locations, such as on their leaves or branches, had increased reproductive success, likely due to the protection against herbivores provided by ants.

On the other hand, butterflies, another group of pollinators, are not affected by ants. This may be due to the way these two groups feed. Butterflies use a long, straw-like organ called a proboscis to suck nectar from a distance, keeping them safe from ants.

Bees, on the other hand, need to get very close to the flower to collect pollen and floral nectar, but ants don't allow them to stay for long. Not surprisingly, the new analysis showed that the presence of ants is detrimental to pollination when extrafloral nectaries are close to flowers, but has a positive effect on plant reproduction when they're located further away.

The conclusions are the result of an analysis of data from 27 empirical studies on the relationships between ants, pollinators, and plants with extrafloral nectaries. The articles were selected from an initial screening of 567 studies after applying inclusion and exclusion criteria. The data were compiled and analyzed with computational tools.

Amanda Vieira da Silva et al, Ants on flowers: Protective ants impose a low but variable cost to pollination, moderated by location of extrafloral nectaries and type of flower visitor, Journal of Ecology (2025). DOI: 10.1111/1365-2745.70087

Culture is overtaking genetics in shaping human evolution, researchers argue

Some Researchers are theorizing that human beings may be in the midst of a major evolutionary shift—driven not by genes, but by culture.

In a paper published in BioScience, they argue that culture is overtaking genetics as the main force shaping human evolution.

"When we learn useful skills, institutions or technologies from each other, we are inheriting adaptive cultural practices. On reviewing the evidence, we find that culture solves problems much more rapidly than genetic evolution. This suggests our species is in the middle of a great evolutionary transition", they say.

Cultural practices—from farming methods to legal codes—spread and adapt far faster than genes can, allowing human groups to adapt to new environments and solve novel problems in ways biology alone could never match. According to the research team, this long-term evolutionary transition extends deep into the past, it is accelerating, and may define our species for millennia to come.

Cultural evolution eats genetic evolution for breakfast, they argue. 

 In the modern environment cultural systems adapt so rapidly they routinely "preempt" genetic adaptation. For example, eyeglasses and surgery correct vision problems that genes once left to natural selection.

Medical technologies like cesarean sections or fertility treatments allow people to survive and reproduce in circumstances that once would have been fatal or sterile. These cultural solutions, researchers argue, reduce the role of genetic adaptation and increase our reliance on cultural systems such as hospitals, schools and governments.

Today, your well-being is determined less and less by your personal biology and more and more by the cultural systems that surround you—your community, your nation, your technologies. And the importance of culture tends to grow over the long term because culture accumulates adaptive solutions more rapidly.

Over time, this dynamic could mean that human survival and reproduction depend less on individual genetic traits and more on the health of societies and their cultural infrastructure.

But, this transition comes with a twist. Because culture is fundamentally a shared phenomenon, culture tends to generate group-based solutions.

Using evidence from anthropology, biology and history, Waring and Wood argue that group-level cultural adaptation has been shaping human societies for millennia, from the spread of agriculture to the rise of modern states. They note that today, improvements in health, longevity and survival reliably come from group-level cultural systems like scientific medicine and hospitals, sanitation infrastructure and education systems rather than individual intelligence or genetic change.
The researchers argue that if humans are evolving to rely on cultural adaptation, we are also evolving to become more group-oriented and group-dependent, signaling a change in what it means to be human.
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In the history of evolution, life sometimes undergoes transitions which change what it means to be an individual. This happened when single cells evolved to become multicellular organisms and social insects evolved into ultra-cooperative colonies. These individuality transitions transform how life is organized, adapts and reproduces. Biologists have been skeptical that such a transition is occurring in humans.

But the researchers suggest that because culture is fundamentally shared, our shift to cultural adaptation also means a fundamental reorganization of human individuality—toward the group.
Cultural organization makes groups more cooperative and effective. And larger, more capable groups adapt—via cultural change—more rapidly. It's a mutually reinforcing system, and the data suggest it is accelerating.
For example, genetic engineering is a form of cultural control of genetic material, but genetic engineering requires a large, complex society. So, in the far future, if the hypothesized transition ever comes to completion, our descendants may no longer be genetically evolving individuals, but societal "superorganisms" that evolve primarily via cultural change.
The researchers emphasize that their theory is testable and lay out a system for measuring how fast the transition is happening. The team is also developing mathematical and computer models of the process and plans to initiate a long-term data collection project in the near future. They caution, however, against treating cultural evolution as progress or inevitability.
They are not suggesting that some societies, like those with more wealth or better technology, are morally 'better' than others. Evolution can create both good solutions and brutal outcomes. They think this might help our whole species avoid the most brutal parts.
The goal of this work goal is to use their understanding of deep patterns in human evolution to foster positive social change.
Still, the new research raises profound questions about humanity's future. "If cultural inheritance continues to dominate, our fates as individuals, and the future of our species, may increasingly hinge on the strength and adaptability of our societies.
And if so, the next stage of human evolution may not be written in DNA, but in the shared stories, systems, and institutions we create together, the researchers conclude.

Timothy M Waring et al, Cultural inheritance is driving a transition in human evolution, BioScience (2025). DOI: 10.1093/biosci/biaf094. academic.oup.com/bioscience/ad … osci/biaf094/8230384

Part 2

Scientists uncover how cellular receptors trigger inflammation and sensory changes

In two new studies, scientists have uncovered detailed blueprints of how certain molecular "gates" in human cells work—findings that could open doors to new treatments for conditions ranging from certain cancers and brain diseases to hearing loss and atherosclerosis, or plaque build-up in the arteries.

They studied a group of proteins known as P2X receptors, which sit on the surface of cells and detect ATP—a molecule best known as the body's energy source inside of cells.

When ATP leaks outside of cells, often as a sign of stress or damage, P2X receptors act like alarm bells, triggering responses related to inflammation, pain and sensory processing.

Extracellular ATP is a universal danger signal. When it builds up outside cells, P2X receptors sense it and change how the cells respond. Understanding these receptors at the atomic level is key to designing drugs that can either calm them down or fine-tune their activity.

In a study published in Nature Communications, researchers examined the molecular structure of the human P2X7 receptor, a protein linked to inflammatory diseases such as cancer, Alzheimer's and atherosclerosis. Despite years of effort, no drugs targeting P2X7 have reached the clinical market, partly because drugs that have worked well in animal models have not had the same success in humans.

Building on a previous study, where they determined how to turn the rat P2X7 receptor off, the team has now mapped how drugs turn off the human P2X7 receptor for the first time. They now know what makes the human receptor different from the receptor that is present in animal models. This is important for understanding how to better customize drugs to fit the binding pockets within the human receptor.

Using that information, the researchers, in collaboration with groups from around the world, designed a new compound referred to as UB-MBX-46. The compound complements the binding pocket in the human receptor, translating to a molecule that blocks the human receptor with high precision and strength.

This is the first time scientists have visualized the human P2X7 receptor and really understood how it is different from others. With that knowledge, they can now create a drug candidate that perfectly fits binding pockets within the human receptor, much like how a key fits in a lock. It gives us hope for developing therapies that have better chances to reach the clinic.

Part 1

A second study published in Proceedings of the National Academy of Sciences examined the human P2X2 receptor, a protein in the same family as the P2X7 receptor, but is predominantly found in the cochlea, the hearing organ of the inner ear.

The P2X2 receptor is involved in hearing processes and in the ear's adaptation to loud noise. Certain genetic mutations of this receptor have been linked to hearing loss. Currently, there are no drugs that target this receptor effectively, and until now, scientists had limited insight into how it functions.

Researchers  used cryo-electron microscopy—a powerful imaging method—to capture 3D structures of the human P2X2 receptor in two states: in a resting state and in a state bound to ATP but desensitized, meaning it's not active anymore. The team discovered unique structural features and pinpointed areas where hearing-related mutations occur.

Together, the studies mark a leap forward in understanding how P2X receptors contribute to a wide range of diseases by triggering inflammation and sensory changes.

Adam C. Oken et al, A polycyclic scaffold identified by structure-based drug design effectively inhibits the human P2X7 receptor, Nature Communications (2025). DOI: 10.1038/s41467-025-62643-8

Franka G. Westermann et al, Subtype-specific structural features of the hearing loss–associated human P2X2 receptor, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2417753122

Part2

 

Scientists shoot lasers into brain cells to uncover how illusions work

An illusion is when we see and perceive an object that doesn't match the sensory input that reaches our eyes.

In a new study published in Nature Neuroscience, researchers identified the key neural circuit and cell type that plays a pivotal role in detecting these illusions—more specifically, their outer edges or "contours"—and how this circuit works.

They discovered a special group of cells called IC–encoder neurons that tell the brain to see things that aren't really there as part of a process called recurrent pattern completion.

Because IC–encoder neurons have this unique capacity to drive pattern completion, the researchers think that they might have specialized synaptic output connectivity that allows them to recreate this pattern in a very effective manner.

They also also know that they receive top-down inputs from higher visual areas. The representation of the illusion arises in higher visual areas first and then gets fed back to the primary visual cortex; and when that information is fed back, it's received by these IC–encoders in the primary visual cortex.

 In the context of the brain and vision—using the above shape diagram—higher levels of the brain interpret the image as a square and then tell the lower-level visual cortex to "see a square" even though the visual stimulus consists of four semi-complete black circles.

They made the discovery by observing the electrical brain activity patterns of mice when they were shown illusory images like the Kanizsa triangle. They then shot beams of light at the IC-encoder neurons, in a process called two-photon holographic optogenetics, when there was no illusory image present.

When this happened, they noticed that even in the absence of an illusion, IC-encoder neurons triggered the same brain activity patterns that exist when an illusory image was present. They successfully emulated the same brain activity by stimulating these specialized neurons.

The findings shed light on how the visual system and perception work in the brain and have implications for diseases where this system malfunctions. In certain diseases you have patterns of activity that emerge in your brain that are abnormal, and in schizophrenia these are related to object representations that pop up randomly.

If you don't understand how those objects are formed and a collective set of cells work together to make those representations emerge, you're not going to be able to treat it; so understanding which cells and in which layer this activity occurs is helpful.

Recurrent pattern completion drives the neocortical representation of sensory inference, Nature Neuroscience (2025). DOI: 10.1038/s41593-025-02055-5.

Geologists discover where energy goes during an earthquake

The ground-shaking that an earthquake generates is only a fraction of the total energy that a quake releases. A quake can also generate a flash of heat, along with a domino-like fracturing of underground rocks. But exactly how much energy goes into each of these three processes is exceedingly difficult, if not impossible, to measure in the field.

Earthquakes are driven by energy that is stored up in rocks over millions of years. As tectonic plates slowly grind against each other, stress accumulates through the crust. When rocks are pushed past their material strength, they can suddenly slip along a narrow zone, creating a geologic fault. As rocks slip on either side of the fault, they produce seismic waves that ripple outward and upward.

We perceive an earthquake's energy mainly in the form of ground shaking, which can be measured using seismometers and other ground-based instruments. But the other two major forms of a quake's energy—heat and underground fracturing—are largely inaccessible with current technologies.

Now  geologists have traced the energy that is released by "lab quakes"—miniature analogs of natural earthquakes that are carefully triggered in a controlled laboratory setting. For the first time, they have quantified the complete energy budget of such quakes, in terms of the fraction of energy that goes into heat, shaking, and fracturing.

They found that only about 10% of a lab quake's energy causes physical shaking. An even smaller fraction—less than 1%—goes into breaking up rock and creating new surfaces. The overwhelming portion of a quake's energy—on average 80%—goes into heating up the immediate region around a quake's epicenter. In fact, the researchers observed that a lab quake can produce a temperature spike hot enough to melt surrounding material and turn it briefly into liquid melt.

The geologists also found that a quake's energy budget depends on a region's deformation history—the degree to which rocks have been shifted and disturbed by previous tectonic motions. The fractions of quake energy that produce heat, shaking, and rock fracturing can shift depending on what the region has experienced in the past.

The team's lab quakes are a simplified analog of what occurs during a natural earthquake. Down the road, their results could help seismologists predict the likelihood of earthquakes in regions that are prone to seismic events.

 Daniel Ortega‐Arroyo et al, "Lab‐Quakes": Quantifying the Complete Energy Budget of High‐Pressure Laboratory Failure, AGU Advances (2025). DOI: 10.1029/2025av001683

Scientists use AI to decode protein structures behind bitter taste detection

Receptor proteins, expressed on the cell surface or within the cell, bind to different signaling molecules, known as ligands, initiating cellular responses. Taste receptors, expressed in oral tissues, interact with tastants, the molecules responsible for the sensation of taste.

Bitter taste receptors (T2Rs) are responsible for the sensation of bitter taste. However, apart from oral tissue, these receptors are also expressed in the neuropod cells of the gastrointestinal tract, which are responsible for transmitting signals from the gut to the brain. Thus, T2Rs might play a crucial role in maintaining the gut-brain axis.

25 types of human T2Rs have been identified to date. However, due to certain complexities, the structure of most of these receptors is not yet elucidated. In recent times, AI-based prediction models have been used to understand protein structure accurately. Previously, a Nobel Prize-winning artificial intelligence (AI)-based model, AlphaFold2 (AF2), was utilized to decipher the structures of T2Rs. However, with the advancement in technology, the model has been updated to its latest version, AlphaFold3 (AF3). The latest model allows a more detailed structural prediction compared to the previous version.

In this study, a group of researchers decided to analyze the structure of T2Rs using the AF3 model and compare the accuracy with the results from the AF2-based prediction study and the available three-dimensional structures of the two T2Rs, T2R14 and T2R46.

The expression of bitter taste receptors in the gastrointestinal tract indicates that they are involved in maintaining the gut-brain axis, glucose tolerance, and appetite regulation. Hence, understanding the structure can provide a better insight into its function.

The researchers obtained the amino acid sequences of all human T2Rs from the UniProt database and used the AF3 model to predict their three-dimensional structures. For comparison, previously generated AF2 prediction data were retrieved from the AlphaFold database. The experimentally determined structures of T2R14 and T2R46 were sourced from the Protein Data Bank (PDB). Various software tools were employed for structure visualization, alignment, and accuracy assessment.

The analysis revealed that AF3 provided consistently more accurate structural predictions than AF2. For T2R14, predictions were benchmarked against 115 cryo-EM structures, and AF3 showed a higher agreement with experimental data. Similarly, for T2R46, comparisons with three experimentally resolved structures confirmed that AF3 achieved the closest match in all cases.

Part1

Similarities in the structure of the T2Rs were also analyzed for this study. For these receptors, part of the protein remains inside the cell, known as the intracellular region, while another part stays outside the cell (extracellular region). The interaction with signal molecules happens in the extracellular region. The study demonstrated that there are more structural similarities and consistencies among the intracellular regions of the T2Rs. The extracellular region of the receptors shows significant structural variation.
"Clustering of proteins is based on their structural similarity and dissimilarity. Based on their findings, the researchers divided the T2Rs into three different clusters.
The structure of T2Rs probably allows them to recognize the thousands of different bitter substances via interaction with another taste receptor-specific G protein, α-gustducin.

"With the receptors' involvement in detecting bitter tastants and maintaining the gut-brain axis, this can play an important role in health and pharmaceutical-based research, specifically targeting lifestyle diseases like diabetes.

 Takafumi Shimizu et al, The three-dimensional structure prediction of human bitter taste receptor using the method of AlphaFold3, Current Research in Food Science (2025). DOI: 10.1016/j.crfs.2025.101146

Part 2

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Kidney transplant rejection associated with changes in lymphatic vessels, new research shows

Scientists have uncovered how lymphatic vessels—the kidney's "plumbing system"—undergo dramatic changes during chronic transplant rejection, becoming structurally disorganized and spreading to unusual parts of the kidney.

Researchers used single-cell sequencing combined with powerful 3D imaging to look at small lymphatic vessels in kidney tissue, comparing healthy kidneys with transplanted kidneys that had been rejected.

Published in the Journal of Clinical Investigation, the research sheds new light on a major unsolved challenge in kidney transplantation and could open the door to new treatments that help transplants last longer.
Kidney transplantation is the most common form of solid organ transplant worldwide. Although the short-term outcomes of kidney transplantation—within a year after surgery—are very good, the long-term outcomes are poorer. Within 10 years, and depending on what country patients are treated in, roughly 50% of kidney grafts will fail.

Researchers know that a big component of why kidney transplant failure occurs is that the patient's immune system attacks parts of the new kidney—such as the blood vessels within it. However, the role of the lymphatic vessels is far less understood. In healthy kidneys, lymphatic vessels act as the organ's plumbing system—playing a vital role in draining excess fluid and helping to regulate immune activity. Therefore, the researchers sought to gain a deeper understanding of the lymphatic system during transplant rejection.

Part 1

Researchers used two different and powerful methods—single cell RNA sequencing and advanced 3D imaging. They studied samples from both healthy and transplant rejection patients.

Single-cell sequencing allows scientists to study the activity of genes in individual cells, one at a time. The researchers did this on a very large scale to generate a huge amount of data. Then the team stained large chunks of kidney tissue while still intact and used a procedure to make it transparent. This 3D imaging helped validate the predictions from the single-cell genetic analysis.

The researchers found that during kidney transplant rejection, the lymphatic vessels within the transplant change their shape and organization. The vessels spread into deeper parts of the kidney known as the medulla, which normally has no lymphatic vessels within it. At the same time, the cell junctions, which are protein anchors that connect cells, go from looking like loose buttons to tightening up like zippers. This is a change that in other contexts is associated with immune cells getting trapped and unable to escape.

Additionally, the researchers found that the balance of T cells inside and around the vessels was disrupted. These T cells released signals that made the vessels switch on molecules acting like "brakes" for the immune system, in an attempt to calm inflammation. However, this protective response was not enough, as other immune cells and antibodies were seen to be directly attacking the kidney. Strikingly, the vessels themselves were also carrying signs that they too were being targeted by the same harmful antibodies.
These findings challenge the view that lymphatic vessels are simply good or bad in transplant rejection. This study suggests that the lymphatic system is normally protective but impaired in transplant rejection as the findings show the vessels change in ways that could encourage rejection by altering their structure and fueling immune responses. The results pave the way for research to focus on regenerating or protecting the lymphatic system in chronic kidney rejection.

Daniyal J. Jafree et al, Organ-specific features of human kidney lymphatics are disrupted in chronic transplant rejection, Journal of Clinical Investigation (2025). DOI: 10.1172/jci168962

Part 2

Man's COVID Infection Lasted 2 Years, Setting a New Record

An immunocompromised man endured ongoing acute COVID-19 for more than 750 days. During this time, he experienced persistent respiratory symptoms and was hospitalized five times.
In spite of its duration, the man's condition differs from long COVID as it wasn't a case of symptoms lingering once the virus had cleared out, but the viral phase of SARS-CoV-2 that continued for over two years.

While this record may be easy to dismiss as something that occurs only to vulnerable people, persistent infections have implications for us all, researchers warn in their new study.

https://www.thelancet.com/journals/lanmic/article/PIIS2666-5247(25)00050-3/fulltext

A new explanation for Siberia's giant exploding craters

Scientists may be a step closer to solving the mystery of Siberia's giant exploding craters. First spotted in the Yamal and Gydan peninsulas of Western Siberia in 2012, these massive holes, known as giant gas emission craters (GECs) can be up to 164 feet deep. They seem to appear randomly in the permafrost and are formed when powerful explosions blast soil and ice hundreds of feet into the air.

For more than a decade, researchers have been coming up with theories about the origin of these craters, ranging from meteor impacts to gas explosions. However, none of these have been able to explain why the craters are only found in this specific area and not in the permafrost elsewhere in the Arctic.

Now, research published in the journal Science of the Total Environment proposes a new and more complete explanation that links the craters to specific factors unique to the two peninsulas, the vast gas reserves in this region and the effects of climate change.

"We propose that the formation of GECs is linked to the specific conditions in the area, including abundant natural gas generation and seepage and the overall limited thickness of the continuous permafrost," wrote the researchers in their paper.

According to their model, GECs form when gas and heat rise from deep underground. The heat melts the permafrost seal (a layer of permanently frozen ground that acts as a lid), making it thinner. Meanwhile, the gas builds up underneath it, and with nowhere to go, the pressure rises. As the climate warms, the permafrost thaws even more, making the lid thinner. Eventually, pressure becomes too great and causes an explosive collapse that creates a large crater.

 Helge Hellevang et al, Formation of giant Siberian gas emission craters (GECs), Science of The Total Environment (2025). DOI: 10.1016/j.scitotenv.2025.180042

Exploding Siberian Craters

Study provides first evidence that plastic nanoparticles can accumulate in the edible parts of vegetables

Plastic pollution represents a global environmental challenge, and once in the environment, plastic can fragment into smaller and smaller pieces.

A new study shows for the first time that some of the tiniest particles found in the environment can be absorbed into the edible sections of crops during the growing process.

The research used radishes to demonstrate, for the first time, that nanoplastics—some measuring as little as one millionth of a centimeter in diameter—can enter the roots, before spreading and accumulating into the edible parts of the plant.

The researchers say the findings reveal another potential pathway for humans and animals to unintentionally consume nanoplastics and other particles and fibers that are increasingly present in the environment.

It also underscores the need for further research to investigate what is an emerging food safety issue, and the precise impacts it could have on environmental and human health.

This study provides clear evidence that particles in the environment can accumulate not only in seafood but also in vegetables. This work forms part of our growing understanding on accumulation, and the potentially harmful effects of micro- and nanoparticles on human health.

Nathaniel J. Clark et al, Determining the accumulation potential of nanoplastics in crops: An investigation of 14C-labelled polystyrene nanoplastic into radishes, Environmental Research (2025). DOI: 10.1016/j.envres.2025.122687

Estimated 16,500 climate change deaths during Europe summer: Study

Scientists estimated this week that rising temperatures from human-caused climate change were responsible for roughly 16,500 deaths in European cities this summer, using modeling to project the toll before official data is released.

The rapidly produced study is the latest effort by climate and health researchers to quickly link the death toll during heat waves to global warming—without waiting months or years to be published in a peer-reviewed journal.

The estimated deaths were not actually recorded in the European cities, but instead were a projection based on methods such as modeling used in previously peer-reviewed studies.

Death tolls during heat waves are thought to be vastly underestimated because the causes of death recorded in hospitals are normally heart, breathing or other health problems that particularly affect the elderly when the mercury soars.

researchers used climate modeling to estimate that global warming made temperatures an average of 2.2 degrees Celsius hotter in 854 European cities between June and August.

Using historical data indicating how such soaring temperatures drive up mortality rates, the team estimated there were around 24,400 excess deaths in those cities during that time.

They then compared this number to how many people would have died in a world that was not 1.3C warmer due to climate change caused by humans burning fossil fuels.

Nearly 70%—16,500—of the estimated excess deaths were due to global warming, according to the rapid attribution study.

This means climate change could have tripled the number of heat deaths this summer, said the study from scientists at Imperial College London and epidemiologists at the London School of Hygiene & Tropical Medicine.

The estimates did reflect previous peer-reviewed research, such as a Nature Medicine study which determined there were more than 47,000 heat-related deaths during the European summer of 2023.

Numerous prominent climate and health researchers also backed the study.

What makes this finding even more alarming is that the methods used in these attribution studies are scientifically robust, yet conservative.

The actual death toll could be even higher, warn the researchers. And what about if the figures for the entire world taken into account! Extremely alarming.

Source: Nature Medicine

Some small asteroids can abruptly explode

Some asteroids are more dangerous than others, according to a report published in Nature Astronomy by an international team of researchers.

The team had presented their findings of an investigation into the impact of small asteroid 2023 CX1 over France in February 2023. This new paper revealed that small asteroids can explode on atmospheric entry.

The researchers confirmed the existence of a new population of asteroids linked to L-type chondrites, capable of fragmenting abruptly in the atmosphere and releasing almost all their energy at once. 

Such asteroids must be accounted for in planetary defense strategies, as they pose an increased risk to populated areas, they say.

Auriane Egal et al, Catastrophic disruption of asteroid 2023 CX1 and implications for planetary defence, Nature Astronomy (2025). DOI: 10.1038/s41550-025-02659-8.

Coral reefs set to stop growing as climate warms

Most coral reefs will soon stop growing and may begin to erode—and almost all will do so if global warming hits 2°C, according to a new study in the western Atlantic. 

The study, published in the journal Nature, projects that more than 70% of the region's reefs will stop growing by 2040—and over 99% will do so by 2100 if warming reaches 2°C or more above pre-industrial levels. The paper is titled "Reduced Atlantic reef growth past 2°C warming amplifies sea-level impacts."

Climate change—along with other issues such as coral disease and deteriorating water quality—reduces overall reef growth by killing corals and impacting colony growth rates, the study concludes.

 Chris Perry, Reduced Atlantic reef growth past 2°C warming amplifies sea-level impacts, Nature (2025). DOI: 10.1038/s41586-025-09439-4. www.nature.com/articles/s41586-025-09439-4

Ostrich and emu ancestor could fly, scientists discover

How did the ostrich cross the ocean?

We have long been puzzled by how the family of birds that includes African ostriches, Australian emus and cassowaries, New Zealand kiwis and South American rheas spread across the world—given that none of them can fly.

However, a study published this week may have found the answer to this mystery: the family's oldest-known ancestors were able to take wing.

The only currently living member of this bird family—which is called paleognaths—capable of flight is the tinamous in Central and South America. But even then, the shy birds can only fly over short distances when they need to escape danger or clear obstacles.

Researchers analyzed the specimen of a lithornithid, the oldest paleognath group for which fossils have been discovered. They lived during the Paleogene period 66–23 million years ago.

The fossil of the bird Lithornis promiscuus was first found in the US state of Wyoming, but had been sitting in the Smithsonian museum's collection.

Because bird bones tend to be delicate, they are often crushed during the process of fossilization, but this one was not. 

Crucially for this study, it retained its original shape. This allowed the researchers to scan the animal's breastbone, which is where the muscles that enable flight would have been attached.

They determined that Lithornis promiscuus was able to fly—either by continuously beating its wings or alternating between flapping and gliding.

But  why did these birds give up the power of flight?

Birds tend to evolve flightlessness when two important conditions are met: they have to be able to obtain all their food on the ground, and there cannot be any predators to threaten them.

Part 1

Research has also recently revealed that lithornithids may have had a bony organ on the tip of their beaks which made them excel at foraging for insects.

But what about the second condition—a lack of predators?

Researchers suspect that paleognath ancestors likely started evolving towards flightlessness after dinosaurs went extinct around 65 million years ago.

With all the major predators gone, ground-feeding birds would have been free to become flightless, which would have saved them a lot of energy.

The small mammals that survived the event that wiped out the dinosaurs would have taken some time to evolve into predators.

This would have given flightless birds "time to adapt by becoming swift runners" like the emu, ostrich and rhea—or even "becoming themselves dangerous and intimidating, like the cassowary.

Quantitative analysis of stem-palaeognath flight capabilities sheds light on ratite dispersal and flight loss, Biology Letters (2025). DOI: 10.1098/rsbl.2025.0320. royalsocietypublishing.org/doi … .1098/rsbl.2025.0320

Part 2

How an essential vitamin B-derived nutrient concentrates in mitochondria

There's a molecule that our body makes from vitamin B₅ that is critical for all of the metabolic processes essential for human life. And when something goes wrong in that molecule's production, it affects nearly every organ system in our body and causes a number of diseases.

Researchers have discovered that up to 95% of this molecule—called essential cofactor coenzyme A (CoA)—is located inside mitochondria, organelles that supply cellular energy and regulate cellular metabolism. But what has not been clear is how CoA gets there.

Reporting in Nature Metabolism, researchers have now uncovered that CoA is trafficked into mitochondria and have identified the mechanisms responsible.

This information, the researchers say, is important for future considerations about when and where to target treatments for diseases in which CoA is implicated.

The researchers were able to identify 33 different CoA conjugates in whole cells as well as 23 CoA conjugates in mitochondria.

The question then was whether the CoA conjugates in the mitochondria were made there or brought in from elsewhere.

In additional experiments, the researchers discovered that the enzyme required to make CoA largely exists outside of mitochondria. Further, when they made cells that lacked the molecular transporters that can move CoA around, mitochondria had far less CoA.

These findings strongly support the idea that CoA is being imported into mitochondria, and these transporters are required for that to happen.

This study advances the fundamental understanding of CoA and how it gets to where it needs to be in order to perform its essential functions. That, in turn, sheds light on how disruptions of this process might contribute to illness.

For instance, mutations in the genes that produce CoA transporters are associated with diseases such as encephalomyopathy, a disorder that can include neurodevelopmental delay, epilepsy, and decreased muscle tone. Mutations in the enzymes that produce CoA have been implicated in neurodegeneration.

In the context of brain disorders, such as neurodegeneration and psychiatric disorders, there's an emerging idea that dysregulated mitochondrial metabolism is a contributor.

Ran Liu et al, Cellular pan-chain acyl-CoA profiling reveals SLC25A42/SLC25A16 in mitochondrial CoA import and metabolism, Nature Metabolism (2025). DOI: 10.1038/s42255-025-01358-y

COVID-19 vaccine responses show four patterns, with 'rapid-decliners' at higher infection risk

Two health care workers get COVID-19 vaccinations on the same day. Both show strong antibody responses initially, but six months later one stays healthy while the other contracts the virus. A new study published in Science Translational Medicine could help explain this difference.

Researchers tracked individuals' antibody levels after vaccinations and identified four distinct patterns of immune response after the first booster vaccination. Notably, people in the group that started with the highest antibody levels but experienced a faster decline were infected earlier. People with lower blood levels of IgA(S) antibodies, which protect the nose and throat, were also at higher risk. The findings suggest that monitoring how antibody levels change over time could assist in identifying individuals at greater risk of infection.

The research team measured antibody levels in 2,526 people over 18 months to see how vaccine responses changed between the first vaccination and later booster shots. They developed a mathematical classification system for COVID-19 vaccine responses using long-term tracking and AI-based computer analysis, becoming the first to systematically identify and characterize the "rapid-decliner" group.

The researchers found that immune responses fell into four clear patterns: Some people maintained high antibody levels over time (durable responders), others started with strong levels but lost them quickly (rapid-decliners), a third group produced few antibodies that also declined rapidly (vulnerable responders), and the rest fell in between (intermediate responders).

A breakthrough or subsequent infection refers to infections that occur after vaccination because the virus overcomes the immune protection that vaccines provide. The researchers found that people whose antibodies declined faster, either because they started low or dropped quickly (vulnerable responders and rapid-decliners), were slightly more likely to get breakthrough infections earlier.

After booster vaccinations, 29% of participants fell into the durable responder category, 28% were vulnerable responders, and 19% were rapid-decliners. The remaining participants showed intermediate patterns. The differences in breakthrough infection rates between groups were modest—5.2% for durable responders and 6% for vulnerable and rapid-decliners.

Part 1

The study also revealed that participants who experienced breakthrough infections had lower levels of IgA(S) antibodies in their blood several weeks after vaccination. These antibodies protect the nose and throat and are our first line of defense against respiratory viruses.

Importantly, the researchers found a strong correlation between blood IgA(S) levels and nasal IgA(S) levels, suggesting that blood tests can reliably indicate the strength of immune protection in airways. As a result, measuring blood IgA(S) levels after vaccination may help identify individuals at higher risk for breakthrough infection, especially among vulnerable groups.
The researchers emphasize the importance of identifying the underlying biological mechanisms responsible for the rapid decline in antibody levels in order to develop more effective vaccination strategies.
Previous research points to factors such as age, genetic variation, vaccine-specific characteristics, and environmental influences, including sleep habits, stress levels, and medications being taken at the same time.
Identifying the rapid-decliner pattern is especially important—it helps explain why some people may need boosters sooner than others.

This could potentially contribute to better, more personalized vaccination strategies.

 Longitudinal antibody titers measured after COVID-19 mRNA vaccination can identify individuals at risk for subsequent infection, Science Translational Medicine (2025). DOI: 10.1126/scitranslmed.adv4214

Part 2

Scientists discover proteins that initiate cellular immunity in bone marrow

Researchers have shown how a critical pathway is fundamental to the immune system.

Establishing cellular immunity depends on the thymus, a lymph gland located in front of the heart. This gland produces and exports T cells, a workhorse white blood cell, out to the rest of the body, using the building blocks of stem cells from the bone marrow. But it has remained a riddle how T cell fate is initiated.

The new paper shows that two protein "transcription factors" called Tcf1 and Lef1 are critical modulators that direct bone marrow stem cells to the T cell path in the thymus.

By carefully removing these proteins via in vivo and ex vivo models, the team of scientists revealed a foundational event in the immune system, which represents essentially the very origin of a functional cellular immune competence.

This discovery illustrates a whole new understanding of T cell formation, and could lead to a wide range of novel approaches in treating immune deficiencies, autoimmune diseases, and optimizing immunotherapies in the ongoing fight against cancer.

"These findings reveal that Tcf1 and Lef1 act much earlier than previously recognized, extending beyond their roles in promoting T-cell lineage specification and commitment at later stages in the thymus," the authors write, adding that the "downstream" Notch signaling pathway is corrupted without these two assisting proteins.

 Xin Zhao et al, Single-cell multiomics identifies Tcf1 and Lef1 as key initiators of early thymic progenitor fate, Science Immunology (2025). DOI: 10.1126/sciimmunol.adq8970

Who are vulnerable to health disinformation?

Individuals who like to think critically are better at identifying false information online, while those with conservative political affiliations struggle more with detecting fake medical information on social media, according to a PLOS One study.

Researchers analyzed responses from 508  participants who reviewed 10 different social media posts that covered diverse health topics with both honest and disinforming claims, with 60% of them falling under the second category.

After viewing the videos and making their honesty judgments, participants were asked to record their responses through online surveys, selecting up to eight reasons from a predefined list. These reasons included the reliability of the source, whether claims were supported by evidence or based on opinion, and the presence or absence of credentials.

Overall, people detected health disinformation with 66% accuracy. This performance is troubling, especially with the world living through an infodemic, a flood of online information where fact and fiction mix freely. Finding trustworthy health guidance online has become increasingly difficult, owing to black box–like social media algorithms that amplify accurate and misleading posts alike.

The COVID-19 pandemic made quite evident the dangers of health disinformation spreading online. Misleading health advice in digital spaces is not just a matter of debate anymore, it is a pressing public health concern with serious real-world consequences.

Previous studies have shown that political leanings can be an indicator of how a person fares at spotting false information online. More recent research, however, highlights a personality trait known as need for cognition—the tendency to seek out and enjoy analytical thinking—as an even stronger predictor.

The results indicated that those with a high need for cognition were significantly better at identifying false information. At the same time, political leanings influenced how certain posts were perceived, particularly on polarizing topics such as COVID-19 vaccines and FDA warnings about drugs like ivermectin and hydroxychloroquine.

The researchers note that the nature of the current infodemic calls for deeper investigation into how disinformation on health issues affects people's everyday lives.

Joey F. George, Political affiliation or need for cognition? It depends on the post: Comparing key factors related to detecting health disinformation in the U.S., PLOS One (2025). DOI: 10.1371/journal.pone.0315259

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Jaguar swims over a kilometer, showing dams are not absolute barriers to large carnivores

Scientists in Brazil recently recorded evidence that a jaguar visited an isolated island in the reservoir area of the Serra da Mesa Hydroelectric Power Dam in northern Goiás State. The same jaguar had been identified on the mainland, 2.48 km away from the island, back in 2020. Both instances were recorded by camera-trap stations, three on the mainland and one on the island, which were set up for an exploratory jaguar survey. The specific jaguar's identity was confirmed by spot-pattern analysis.

After analyzing possible aquatic trajectories for the jaguar, the researchers found that it had two possible paths. Either the jaguar swam the direct 2.48 km to the island, or used a stepping-stone-like islet, taking a 1.06 km swim, followed by a 1.27 km swim to get to the island.

Previous records indicated a maximum swimming distance of around 200 meters for jaguars. Given the possible paths here, this jaguar had to swim a minimum of 1.27 km, possibly more, shattering previous records. This impressive feat is documented in a new bioRxiv preprint, in which the researchers involved also discuss a newly proposed aquatic-cost scale for assessing the ecological connectivity between landmasses.

It was previously thought that reservoirs, like Serra da Mesa, acted as absolute barriers for large carnivores due to prior instances of predator collapse on islands further than a kilometer away from the mainland. Yet, genetic studies across the Amazon River indicated only partial segregation, suggesting occasional crossings.

The study authors explain, "These rare events suggest that, under favorable conditions (e.g., warm water, low currents, presence of stepping-stone islands), large felids may occasionally exploit aquatic corridors that appear to be initially insurmountable."

The research team proposes a new ordinal aquatic-cost scale for modeling connectivity between landmasses, described by low/medium/high cost ranking for water crossings. Low cost was defined as less than 300 m; medium as 300–1,000 m with stepping-stones; and high as greater than 1,000 m of open water. This scale is meant to help inform future hydropower impact assessments and corridor planning for jaguar conservation.

Leandro Silveira et al, Kilometre-scale jaguar swimming reveals permeable hydropower barriers: implications for conservation in the Cerrado hotspot, bioRxiv (2025). DOI: 10.1101/2025.09.05.674446

Carbon credits have little to no effect on making companies greener, study reveals

Many companies across the world use carbon credits as part of their climate strategies to offset emissions. A carbon credit is a certificate that represents the reduction, avoidance or removal of one ton of carbon dioxide from the atmosphere. While organizations claim these credits help them reduce their environmental impact, there is debate about whether companies that buy credits decarbonize faster. However, an in-depth study of 89 multinationals, published in Nature Communications, reveals that companies that purchase credits do not decarbonize any quicker than those that do not.

Voluntary emission offsetting is not associated with positive corporate environmental performance. Therefore, it is not a reliable alternative to regulatory measures, such as compliance carbon pricing, wrote the researchers in their paper.

Researchers examined over 400 sustainability reports and self-reported environmental data from multinational companies working in the oil and gas, automotive and airline industries. These were firms that bought and used roughly a quarter of all carbon credits that were available in 2022.
They then compared how much these companies reduced their emissions between 2018 and 2023 and how ambitious their climate goals were with the amount of carbon credits they purchased. To make sure the company data was accurate, the researchers checked it against major carbon credit agencies.

The study found that, on average, companies spend about 1% of their capital spending on carbon credits, which means they account for a small share of the overall budget. The research also highlights a problem where carbon offsets can compete with internal decarbonization.

For some large-scale off-setters buying large amounts of carbon credits can divert funds from internal projects that would directly cut their emissions. Other companies use carbon credits to meet their goals because it is cheaper and easier than making internal structural changes.

The researchers suggest a way forward, namely a shift away from voluntary carbon offsetting to regulatory measures, such as carbon compliance. This is a government-mandated system where companies must pay for the carbon they emit. The main goal here is to create a financial incentive for companies to reduce their carbon emissions.

Niklas Stolz et al, The negligible role of carbon offsetting in corporate climate strategies, Nature Communications (2025). DOI: 10.1038/s41467-025-62970-w

Our body organs cannot simply be classified as male or female

Biological sex is usually described in simple binary terms: male or female. This works well for germ cells (sperm versus eggs), but for other body organs it is of little help.

A new study shows that our organs form a mosaic of sex-specific characteristics—far removed from the strict division into male and female.

The research shows that in many organs, sex-specific patterns overlap strongly. Only testes and ovaries are clearly distinguishable. All other organs show mosaic-like combinations of male and female characteristics.

Sex-specific genes stand out most strongly in the sexual organs. But in other organs the picture is more complex. In mice, the kidney and liver show large differences, while in humans it is adipose tissue. By contrast, the brain shows only minimal differences in both species—consistent with previous studies of human brain structure.

To capture this diversity, the researchers developed a Sex-Bias Index (SBI). This index summarizes the activity of all male- and female-specific genes in an organ into a single value. While the index shows a clear separation in the sexual organs, in other organs the values are often so close that men and women cannot be distinguished reliably.

For example, a man's heart may be more "female-like" than that of some women. Even within an individual, organs can differ—the heart more female, the liver more male. This results in a mosaic of sex characteristics that contradicts the idea of a clear-cut binary.

The study, published in eLife, also shows that sex-specific gene activity in organs evolves very rapidly—much faster than genes active in both sexes equally. Even between mouse species that diverged less than 2 million years ago, the majority of genes have lost or even switched their sex-specific role.

As a result, when comparing humans and mice, only very few genes retain conserved sex-specific activity. This also means that mouse models are of very limited use when applied to sex-specific medicine in humans.

Part 1

The researchers further found that sex-specific genes often occur in "modules" that are regulated together. Evolution therefore alters sex differences not by changing single genes, but by rearranging whole networks. The driving force here is sexual selection—the ongoing evolutionary conflict between the interests of males and females. This conflict can never be fully resolved, as every adaptation creates new contrasts.

When applied to human tissues, the method reveals a clear pattern: markedly fewer sex-specific genes than in mice, and even stronger overlaps between men and women. In our species, differences are therefore weaker, further undermining the idea of a strict binary classification.

The study concludes that while the sexual organs show a clear binary pattern, most other tissues display a continuum of sex-specific gene activity—a dynamic spectrum that varies both between species and between individuals.

Sex is therefore not rigid and clear-cut, but shaped by evolution, overlaps and individual differences. Instead of classifying the body strictly as male or female based on molecular features, it should be understood as a complex mosaic.

Chen Xie et al, Fast evolutionary turnover and overlapping variances of sex-biased gene expression patterns defy a simple binary sex classification of somatic tissues, eLife (2025). DOI: 10.7554/elife.99602.4

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Grue jay? Rare hybrid bird identified 

Biologists who have reported discovering a bird that's the natural result of a green jay and a blue jay's mating, say it may be among the first examples of a hybrid animal that exists because of recent changing patterns in the climate. The two different parent species are separated by 7 million years of evolution, and their ranges didn't overlap as recently as a few decades ago.

They  think it's the first observed vertebrate that's hybridized as a result of two species both expanding their ranges due, at least in part, to climate change.

Past vertebrate hybrids have resulted from human activity, like the introduction of invasive species, or the recent expansion of one species' range into another's—think polar bears and grizzlies—but this case appears to have occurred when shifts in weather patterns spurred the expansion of both parent species.

Hybridization is probably way more common in the natural world than researchers know about because there's just so much inability to report these things happening.

The researchers did not opt to name the hybrid bird, but other naturally occurring hybrids have received nicknames like "grolar bear" for the polar bear-grizzly hybrid, "coywolf" for a creature that's part coyote and part wolf and "narluga" for an animal with both narwhal and beluga whale parents.

Brian R. Stokes et al, An Intergeneric Hybrid Between Historically Isolated Temperate and Tropical Jays Following Recent Range Expansion, Ecology and Evolution (2025). DOI: 10.1002/ece3.72148

Age 70 identified as cutoff for chemotherapy benefit in colorectal cancer

Colorectal cancer remains a leading cause of cancer death, with incidence rising among older adults. One of the most pressing clinical questions has been whether elderly patients should receive oxaliplatin, a standard component of adjuvant chemotherapy that is known to cause serious side effects.

Researchers  examined health records from more than 8,500 patients with stage II or III colorectal cancer who underwent surgery followed by chemotherapy between 2014 and 2016. Patients were divided into two groups: those treated with oxaliplatin-based combinations, and those given standard chemotherapy alone. Using advanced statistical methods, the researchers systematically tested whether an age threshold existed at which oxaliplatin stopped providing survival benefits.

The results were decisive. In stage III patients aged 70 or younger, oxaliplatin reduced the risk of death by 41%, boosting five-year survival from 78% to nearly 85%. But in those older than 70, oxaliplatin did not improve survival and was linked to higher rates of treatment discontinuation. In fact, almost 40% of older patients receiving oxaliplatin stopped chemotherapy early, often due to toxicity. For stage II patients of any age, oxaliplatin showed no added survival benefit.

The most important point is that oxaliplatin improves survival only in patients with stage III colorectal cancer who are aged 70 years or younger. Beyond 70, the benefit disappears, and oxaliplatin is associated with higher discontinuation rates due to toxicity.

These findings have immediate real-world applications.

Oncologists can use this age threshold to make more precise, evidence-based choices about whether to add oxaliplatin, avoiding unnecessary toxicity in patients unlikely to benefit.

The broader significance extends to health care policy. Avoiding ineffective chemotherapy in older patients may help reduce costs, complications, and hospitalizations. Health systems could redirect resources to therapies and supportive care that make a greater difference in survival and quality of life. The research also sets the stage for longer-term changes in global cancer care.

Jun Woo Bong et al, Older Age Threshold for Oxaliplatin Benefit in Stage II to III Colorectal Cancer, JAMA Network Open (2025). DOI: 10.1001/jamanetworkopen.2025.25660

India health alert after 'brain-eating' amoeba rise

India has issued a health alert after infections and deaths caused by a rare water-borne "brain-eating" amoeba doubled compared to last year in the southern state of Kerala.

Officials were "conducting tests on a large scale across the state to detect and treat cases."

Officials reported 19 deaths and 72 infections of the Naegleria fowleri amoeba this year, including nine deaths and 24 cases in September alone.

Last year, the amoeba killed nine people out of 36 reported cases.

The US Centers for Disease Control and Prevention (CDC) says it is often called a "brain-eating amoeba" because it can "infect the brain and destroy brain tissue."

If the amoeba reaches the brain, it can cause an infection that kills over 95% of those affected.

Infections are "very rare but nearly always fatal," the CDC notes.

The amoeba lives in warm lakes and rivers and is contracted by contaminated water entering the nose. It does not spread from person to person.

The World Health Organization says that symptoms include headache, fever and vomiting, which rapidly progresses to "seizures, altered mental status, hallucinations, and coma."

Source: News Agencies