Turtle Dance
Researchers found that the turtles exhibited significantly higher levels of ‘turtle dance’ behaviour when they were in their designated feeding fields, strongly suggesting that they could distinguish between the two magnetic fields.

When somebody says 'shut up!', how do you stop speaking?

A premotor cortical network in the brain allows people to voluntarily stop speaking, study suggests

Speech is a unique human ability that is known to be supported by various motor and cognitive processes. When humans start speaking, they can decide to cease at any point; for instance, if they are interrupted by something happening or by another person speaking to them.

The ability to voluntarily stop speaking plays a central role in social interactions, as it allows people to engage in conversations with others while adaptively responding to social cues, environmental stimuli or interruptions.

Researchers  recently set out to better understand how the human brain controls the ceasing of speech using tools to record neurophysiological signals. Their paper, published in Nature Human Behaviour, unveils a previously unknown premotor cortical network that could support voluntary speech inhibition.

Researchers recruited 13 patients diagnosed with treatment-resistant epilepsy who had electrodes implanted on their brains' surfaces to better understand the brain regions that contribute to their epileptic seizures. These patients were asked to complete a speech-stopping task, which asked them to follow instructions on when to start and stop speaking, while their neural activity was recorded.

Neural recordings revealed distinct activity in the premotor frontal cortex correlated with stopping speech. This activity was found in largely separate cortical sites from regions encoding vocal tract articulatory movements. Moreover, this activity primarily occurred with abrupt stopping in the middle of an utterance, rather than naturally completing a phrase.

The findings gathered by this team of researchers hint at the existence of a specialized brain mechanism that supports the voluntary control of speech.

The researchers conducted further tests aimed at validating the existence of this mechanism by stimulating specific parts of the premotor frontal cortex.

Electrocortical stimulation at many premotor sites with inhibitory stop activity caused involuntary speech arrest, which contradicts previous clinical interpretations of this effect as evidence for critical centers of speech production," wrote the team in their paper. "Together, these results suggest a previously unknown premotor cortical network that supports the inhibitory control of speech, providing implications for understanding both natural and altered speech production."

Overall, the results of this study suggest that the human ability to voluntarily stop speech is supported by a particular inhibitory control neural network that had not been uncovered before.

Lingyun Zhao et al, Inhibitory control of speech production in the human premotor frontal cortex, Nature Human Behaviour (2025). DOI: 10.1038/s41562-025-02118-4

Cells 'speed date' to find their neighbours when forming tissues

In developing hearts, cells shuffle around, bumping into each other to find their place, and the stakes are high: pairing with the wrong cell could mean the difference between a beating heart and one that falters.

A study published in the Biophysical Journal demonstrates how heart cells go about this "matchmaking" process. The researchers model the intricate movements of these cells and predict how genetic variations could disrupt the heart development process in fruit flies.

In both humans and fruit flies, the heart's tissues arise from two distinct regions of the embryo, which are initially far apart. As development progresses, these cells journey toward each other, ultimately merging into a tube-like shape that will become the heart. For the heart to develop correctly, these cells must align and pair up precisely.

As the cells come together, they jiggle and adjust, and somehow always end up pairing with a heart cell of the same type. This observation inspired researchers to explore how cells match up in the first place and how they know when they've found the right fit.

Developing heart cells have tentacle-like protrusions called filopodia, which probe and grab onto potential partners.

Earlier researchers found that proteins create waves that pull mismatched cells apart, giving them another chance to find the right match.

It's basically like cells are speed dating. They have just a few moments to determine if they're a good match, with molecular 'friends' ready to pull them apart if they're not compatible.

The researchers found that heart cells seek stability where they remain closest to stillness—like a rolling ball that eventually comes to a stop, known as energy equilibrium in physics.

In developing heart cells, this principle applies when cells find a balance between connection forces and their ability to adjust to strain—also known as adhesive energy and elasticity. Based on this observation, the team developed a model that shows how cells can self-organize.

Scientists tested their model on fruit fly hearts with mutations and misalignments. By calculating the adhesive energy between different cell types and assessing tissue elasticity, the model predicted how cells would match and rearrange.

Although rare, sometimes the heart tube ends up with one cell on one side when it should have two, or two cells when there should be four. The model produced outcomes that closely mirrored what was observed in real embryos.

This  new model not only enhances our understanding of how cells match and align during heart development but also has broader applications. Similar cell-matching processes are crucial in neuronal connections, wound repair, and facial development, where hiccups can lead to conditions like cleft lip.

Interfacial energy constraints are sufficient to align cells over large distances, Biophysical Journal (2025). DOI: 10.1016/j.bpj.2025.02.011

Food insecurity raises risk of heart disease over time: A 20 year study

Struggling to afford food today could mean heart problems tomorrow. Young adults experiencing food insecurity have a 41% greater risk of developing heart disease in midlife, even after accounting for demographic and socioeconomic factors, according to a new  Medicine study.

Food insecurity means struggling to get enough nutritious food to stay healthy.

That makes it a clear target for prevention—if we address food insecurity early, we may be able to reduce the burden of heart disease later."

The study was published in JAMA Cardiology.

Among the 3,616 study participants, those experiencing food insecurity were 41% more likely to develop cardiovascular disease than their food-secure counterparts. Over the study period, 11% of food-insecure individuals developed heart disease, compared to 6% of those with adequate food access.

By following people over two decades, researchers were able to show that food insecurity, on its own, significantly increases the risk of developing cardiovascular disease. 

 Food Insecurity and Incident Cardiovascular Disease Among Black and White US Individuals, 2000-2020, JAMA Cardiology (2025). DOI: 10.1001/jamacardio.2025.0109

Mosquito pain receptors found to be less sensitive during extreme heat, which could nullify some natural bug sprays

Hotter temperatures may render natural insect repellents less effective against mosquitoes, according to a new study. Researchers found that a pain receptor called TRPA1 becomes less sensitive in mosquitoes when exposed to heat, meaning that the chemical cues that typically trigger insect avoidance behaviors are prevented from activating as strongly.

TRPA1, also known as the "wasabi receptor," helps animals detect noxious heat and harmful chemicals. In humans, this receptor can induce eye and skin irritation. In mosquitoes, it influences which hosts the insects find most alluring—specifically, those unprotected by repellents that drive them away.

What the researchers now  found was that the chemicals were not able to activate the mosquito wasabi receptor as effectively when temperatures exceeded the heat activation threshold.

Typical insect repellents create a chemical barrier that discourages proximity and prevents mosquitoes from reaching their target. Yet because their receptors are desensitized in warmer temperatures, natural substances like citronellal and catnip oil, known for their repellent properties, would be less effective. Products with those ingredients may be less effective if you're using them at temperatures that are considered extreme heat events, say the researchers.

Yeaeun Park et al, Heat activation desensitizes Aedes aegypti transient receptor potential ankyrin 1 (AaTRPA1) to chemical agonists that repel mosquitoes, Pesticide Biochemistry and Physiology (2025). DOI: 10.1016/j.pestbp.2025.106326

128 New Moons Found Orbiting Saturn

The race between Jupiter and Saturn for the most moons in the Solar System may have just finally come screeching to a halt.

A team of scientists has found a whopping 128 previously unknown moons hanging around Saturn, in a discovery officially recognized by the International Astronomical Union. This brings the planet's total number of known moons to 274, leaving Jupiter, with its mere 95 moons, in the dust.

https://arxiv.org/abs/2503.07081

Restored grasslands need 75+ years for full biodiversity recovery, study finds

Recovered grasslands need more than 75 years of continuous management to regain their biodiversity because specialized pollinators are slow to return. This finding underscores the importance of preserving old grasslands as reservoirs of biodiversity, even if it is just as ski slopes.

Grasslands worldwide are rapidly disappearing due to land-use conversion and abandonment, leading to a well-documented loss of grassland biodiversity. Restoring abandoned grasslands by removing woody vegetation and resuming traditional land management practices has positive effects on biodiversity.

However, it is also known that this diversity lags behind that of old grasslands that have been under continued management for up to several millennia. The reasons for this are not really clear and satisfying solutions have not been proposed, say the experts.

The results of a study   published in the Journal of Applied Ecology paint a consistent picture. It takes 75 years of continuous management for the plant diversity in recovered grasslands to finally reach levels comparable to ancient grasslands.

However, that's still not enough for the pollinator community. Even after 75 years, pollinators are still less specialized and less successful at pollinating the plants, although the community continuously shifts towards higher specialization and successful pollination as grasslands get older.

The finding shows that once valuable old grasslands are lost, their restoration cannot be achieved quickly.

Long-term management is required for the recovery of pollination networks and function in restored grasslands, Journal of Applied Ecology (2025). DOI: 10.1111/1365-2664.70017

Watching nature scenes can reduce pain, neuroimaging study shows

A new neuroimaging study has revealed that viewing nature can help ease how people experience pain, by reducing the brain activity linked to pain perception.

Published in the journal Nature Communications  the research offers a promising foundation for new types of non-pharmacological pain treatments. The paper is titled "Nature exposure induces analgesic effects by acting on nociception-related neural processing."

Using an fMRI scanner, researchers monitored the brain activity of 49 participants as they received pain delivered through a series of small electric shocks. When they were watching videos of a natural scene compared to a city or an indoor office, participants not only reported feeling less pain, but scans showed the specific brain responses associated with processing pain changed too.

The study used advanced machine-learning to analyze the brain networks related to pain processing. The team discovered that the raw sensory signals the brain receives when something hurts were reduced when watching a carefully designed, high-quality, virtual nature scene.

The study confirmed previous findings that suggest nature can reduce subjective reports of pain, and also marks the first clear demonstration of how natural environments influence the brain, helping to buffer against unpleasant experiences.

Nature exposure induces analgesic effects by acting on nociception-related neural processing', Nature Communications (2025). DOI: 10.1038/s41467-025-56870-2

How the brain makes decisions more quickly than computers in risky situations

Research inspired by the principles of quantum mechanics, researchers from Pompeu Fabra University (UPF) and the University of Oxford reveal new findings to understand why the human brain is able to make decisions quicker than the world's most powerful computer in the face of a critical risk situation. The human brain has this capacity despite the fact that neurons are much slower at transmitting information than microchips, which raises numerous unknown factors in the field of neuroscience.

The research is published in the journal Physical Review E.

It should be borne in mind that in many other circumstances, the human brain is not quicker than technological devices. For example, a computer or calculator can resolve mathematical operations far faster than a person. So, why is it that in critical situations—for example, when having to make an urgent decision at the wheel of a car—the human brain can surpass machines?

Most accurate computational model yet to analyze connections between farthest neurons

This recent research clarifies this matter thanks to the design of a new model of brain computational analysis, called CHARM (Complex Harmonics Decomposition). It is the most accurate model to date for examining the functions of long-distance brain connections, which link neurons that are far apart and play a fundamental role in the brain dynamics that are activated when making critical decisions. It is also the first model to apply quantum mechanics as an instrument for analyzing the brain.

The  researchers describe this model in their study. 

Part 1

Long-distance neural connections are comparable to those connecting computers in distant countries
To design the CHARM model, the researchers started with a paradigm of analysis of brain dynamics that we could compare to the Internet. In certain scenarios, such as risk situations, neurons distributed in different brain regions, both close to and far from each other, are joined by different connections. These connections enable pooling the information processing power of all the neurons in the network.

Thus, although groups of neurons located in different brain regions have a limited capacity to transmit information, when they pool their resources in a network, they attain far greater processing power. This paradigm has gained strength over the past decade, as opposed to the traditional approach whereby neural regions only function in a localized manner.
In a critical state, the efficiency of long-distance neural connections is enhanced
The researchers have found that the efficiency of long-distance connections is enhanced when the brain is dominated by critical dynamics, which lead it to a state of transition between order and chaos.
We could assimilate this state to a transitional phase like the process whereby water becomes ice. At this critical point, the brain has exacerbated properties, the researchers point out.
The CHARM model has enabled ascertaining precisely the functions of these long-distance connections in this or other states, for the first time integrating the principles of quantum mechanics into a system of computational brain analysis.
By adopting the Schrödinger equation we can model these interactions with a degree of precision that was previously beyond our reach.
The research findings can also have numerous applications for improving the diagnosis and treatment of various neurological diseases, such as schizophrenia or depression. Long-distance neuronal connection dysfunctions are key to understanding the origin of these diseases.

Moreover, the study opens the door to new lines of research in the field of artificial intelligence (AI). Currently, artificial neural networks are based on a localized, non-distributed model. In the future, the possible application of the distributed paradigm to AI could multiply its current capabilities, although many technical difficulties must still be overcome to enable this.

 Gustavo Deco et al, Complex harmonics reveal low-dimensional manifolds of critical brain dynamics, Physical Review E (2025). DOI: 10.1103/PhysRevE.111.014410

Part 2

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Researchers turn skin cells directly into neurons for cell therapy

Converting one type of cell to another—for example, a skin cell to a neuron—can be done through a process that requires the skin cell to be induced into a pluripotent stem cell, then differentiated into a neuron. Researchers  have now devised a simplified process that bypasses the stem cell stage, converting a skin cell directly into a neuron.

Working with mouse cells, the researchers developed a conversion method that is highly efficient and can produce more than 10 neurons from a single skin cell. If replicated in human cells, this approach could enable the generation of large quantities of motor neurons, which could potentially be used to treat patients with spinal cord injuries or diseases that impair mobility.

As a first step toward developing these cells as a therapy, the researchers showed that they could generate motor neurons and engraft them into the brains of mice, where they integrated with host tissue.

Previously scientists in Japan showed that by delivering four transcription factors to skin cells, they could coax them to become induced pluripotent stem cells (iPSCs). Similar to embryonic stem cells, iPSCs can be differentiated into many other cell types. This technique works well, but it takes several weeks, and many of the cells don't end up fully transitioning to mature cell types.

Oftentimes, one of the challenges in reprogramming is that cells can get stuck in intermediate states. So scientists are trying direct conversion, where instead of going through an iPSC intermediate, they are going directly from a somatic cell to a motor neuron.

They have demonstrated this type of direct conversion before, but with very low yields—fewer than 1%. 

In the first of the new Cell Systems papers,  scientists now reported a way to streamline the process so that skin cells can be converted to motor neurons using just three transcription factors, plus the two genes that drive cells into a highly proliferative state.

The researchers also developed a slightly different combination of transcription factors that allowed them to perform the same direct conversion using human cells, but with a lower efficiency rate—between 10 and 30%, the researchers estimate. This process takes about five weeks, which is slightly faster than converting the cells to iPSCs first and then turning them into neurons.

Once the researchers identified the optimal combination of genes to deliver, they began working on the best ways to deliver them, which was the focus of the second  Cell Systems paper.

Part 1

They tried out three different delivery viruses and found that a retrovirus achieved the most efficient rate of conversion. Reducing the density of cells grown in the dish also helped to improve the overall yield of motor neurons. This optimized process, which takes about two weeks in mouse cells, achieved a yield of more than 1,000%.

Proliferation history and transcription factor levels drive direct conversion to motor neurons, Cell Systems (2025). DOI: 10.1016/j.cels.2025.101205. www.cell.com/cell-systems/full … 2405-4712(25)00038-9

Compact transcription factor cassettes generate functional, engraftable motor neurons by direct conversion, Cell Systems (2025). DOI: 10.1016/j.cels.2025.101206. www.cell.com/cell-systems/full … 2405-4712(25)00039-0

Part 2

Violent supernovae 'triggered at least two Earth extinctions,' study suggests

At least two mass extinction events in Earth's history were likely caused by the "devastating" effects of nearby supernova explosions, a new study suggests.

Researchers note that   these super-powerful blasts—caused by the death of a massive star—may have previously stripped our planet's atmosphere of its ozone, sparked acid rain and exposed life to harmful ultraviolet radiation from the sun.

They think a supernova explosion close to Earth could be to blame for both the late Devonian and Ordovician extinction events, which occurred 372 and 445 million years ago respectively.

The Ordovician extinction killed 60% of marine invertebrates at a time when life was largely confined to the sea, while the late Devonian wiped out around 70% of all species and led to huge changes in the kind of fish that existed in our ancient seas and lakes.

Past research has failed to identify a clear cause for either event, although they are thought to have been linked to the depletion of Earth's ozone layer, which could have been triggered by a supernova.

The new study, published in Monthly Notices of the Royal Astronomical Society, found that the rate supernovae occur near to our planet is consistent with the timings of both mass extinctions.

The authors say it is a "a great illustration for how massive stars can act as both creators and destructors of life."

That's because supernovae are also known to spread the heavy elements that help form and support life across the universe.

Supernovae occur when massive stars reach the end of their lives, run out of fuel, cool off, and then collapse under the pressure of gravity. The explosions are the biggest humans have ever seen.

Supernova explosions bring heavy chemical elements into the interstellar medium, which are then used to form new stars and planets.

But if a planet, including the Earth, is located too close to this kind of event, this can have devastating effects.

Supernova explosions are some of the most energetic explosions in the universe.

"If a massive star were to explode as a supernova close to the Earth, the results would be devastating for life on Earth. This research suggests that this may have already happened", they add.

The researchers came to their conclusion after carrying out a "census" of massive stars within a kiloparsec (around 3,260 light-years) of the sun.

Alexis L. Quintana et al, A census of OB stars within 1 kpc and the star formation and core collapse supernova rates of the Milky Way, Monthly Notices of the Royal Astronomical Societyacademic.oup.com/mnras/article … 0.1093/mnras/staf083 . On arXiv (2025). DOI: 10.48550/arxiv.2503.08286

Oral snakebite treatment

Researchers  have completed a Phase I clinical trial for a new oral treatment for snakebite.

The study, conducted by researchers from the Center for Snakebite Research & Interventions (CSRI) at LSTM and the Kenya Medical Research Institute (KEMRI) Wellcome Trust Research Programme in Kilifi and published in the journal eBioMedicine, shows that the drug, unithiol, is safe, well tolerated, and easy to administer in remote rural clinics, paving the way for its development as a field-ready treatment.

Unithiol is already approved for treating heavy metal poisoning but was identified for study in the treatment of snakebite envenoming due to its ability to neutralize snake venom metalloproteinases (SVMPs). These zinc-based toxin components, found in the venoms of vipers and many other snakes, are responsible for causing severe tissue damage and life-threatening bleeding in snakebite patients.

Snakebite envenoming remains a major global health challenge, causing more than 140,000 deaths a year, mainly in rural Sub-Saharan Africa, Latin America and Asia. Current antivenom treatments are costly, can cause severe side effects and must be administered intravenously in hospital settings, barriers that delay life-saving intervention.

The animal-derived antivenoms used today are based on 100-year-old principles.

Small molecule therapeutics, such as unithiol, have the potential to be safer and cheaper and can be taken easily as a pill.

The phase 1 trial  has shown that unithiol is safe even at the high doses that the researchers think will be needed to treat snakebite, so they could be on the cusp of bringing snakebite treatment  into the 21st century and vastly improving patient outcomes.

Preclinical research by LSTM scientists previously demonstrated that unithiol could prevent the worst effects of venom and potentially save lives. The phase 1 clinical trial assessed different doses of unithiol in oral and intravenous forms. All showed no serious side effects, even at the maximum dose, and analysis of participants' blood found that the drug was rapidly absorbed and present at levels expected to inhibit snake venom toxins.

Based on these findings, the LSTM team will advance unithiol to phase 2 clinical trials, where the drug will be tested in patients who have been bitten and envenomed by snakes. If successful, unithiol could be rapidly deployed in rural clinics and first-aid settings, buying snakebite victims valuable time to get to a hospital and reducing the severity of envenoming.

A word of caution though: While unithiol may not be a cure by itself, the scientists hope that it will prevent the worst effects of snakebite envenoming and buy victims valuable time to get to a hospital, thereby reducing their risk of death or disability.

 Michael Abouyannis et al, Development of an oral regimen of unithiol for the treatment of snakebite envenoming: a phase 1 open-label dose-escalation safety trial and pharmacokinetic analysis in healthy Kenyan adults, eBioMedicine (2025). DOI: 10.1016/j.ebiom.2025.105600

Scientists from IOCB Prague are on track of finding a treatment for autoimmune hair loss

WORLD-FIRST: Aussie man leaves hospital with totally artificial Titanium heart

'Microlightning' in water droplets may have sparked life on Earth

Life may not have begun with a dramatic lightning strike into the ocean but from many smaller "microlightning" exchanges among water droplets from crashing waterfalls or breaking waves.

New research shows that water sprayed into a mixture of gases thought to be present in Earth's early atmosphere can lead to the formation of organic molecules with carbon-nitrogen bonds, including uracil, one of the components of DNA and RNA.

The study, published in the journal Science Advances, adds evidence—and a new angle—to the much-disputed Miller-Urey hypothesis, which argues that life on the planet started from a lightning strike. That theory is based on a 1952 experiment showing that organic compounds could form with the application of electricity to a mixture of water and inorganic gases.

In the current study, the researchers found that water spray, which produces small electrical charges, could do that work all by itself, no added electricity necessary.

Microelectric discharges between oppositely charged water microdroplets make all the organic molecules observed previously in the Miller-Urey experiment, and the researchers propose that this is a new mechanism for the prebiotic synthesis of molecules that constitute the building blocks of life.

For a couple billion years after its formation, Earth is believed to have had a swirl of chemicals but almost no organic molecules with carbon-nitrogen bonds, which are essential for proteins, enzymes, nucleic acids, chlorophyll, and other compounds that make up living things today.

How these biological components came about has long puzzled scientists, and the Miller-Urey experiment provided one possible explanation: that lightning striking into the ocean and interacting with early planet gases like methane, ammonia, and hydrogen could create these organic molecules.

Critics of that theory have pointed out that lightning is too infrequent and the ocean too large and dispersed for this to be a realistic cause.

Part 1

Scientists propose another possibility with this research. The researchers first investigated how droplets of water developed different charges when divided by a spray or splash.

They found that larger droplets often carried positive charges, while smaller ones were negative. When the oppositely charged droplets came close to each other, sparks jumped between them. The researchers call this "microlightning," since the process is related to the way energy is built up and discharged as lightning in clouds. The researchers used high-speed cameras to document the flashes of light, which are hard to detect with the human eye.

Even though the tiny flashes of microlightning may be hard to see, they still carry a lot of energy. The researchers demonstrated that power by sending sprays of room-temperature water into a gas mixture containing nitrogen, methane, carbon dioxide, and ammonia gases, which are all thought to be present on early Earth.
This resulted in the formation of organic molecules with carbon-nitrogen bonds, including hydrogen cyanide, the amino acid glycine, and uracil.

The researchers argue that these findings indicate that it was not necessarily lightning strikes, but the tiny sparks made by crashing waves or waterfalls that jump-started life on this planet.
On early Earth, there were water sprays all over the place—into crevices or against rocks, and they can accumulate and create this chemical reaction, they say. We usually think of water as so benign, but when it's divided in the form of little droplets, water is highly reactive.

Yifan Meng et al, Spraying of Water Microdroplets Forms Luminescence and Causes Chemical Reactions in Surrounding Gas, Science Advances (2025). DOI: 10.1126/sciadv.adt8979. www.science.org/doi/10.1126/sciadv.adt8979

Part 2

Genomic study indicates our capacity for language emerged 135,000 years ago

 When did human language as we know it emerge? A new survey of genomic evidence suggests our unique language capacity was present at least 135,000 years ago. Subsequently, language might have entered social use 100,000 years ago.

Our species, Homo sapiens, is about 230,000 years old. Estimates of when language originated vary widely, based on different forms of evidence, from fossils to cultural artifacts. The authors of the new analysis took a different approach. They reasoned that since all human languages likely have a common origin—as the researchers strongly think—the key question is how far back in time regional groups began spreading around the world.

The logic is simple: Every population branching across the globe has human language, and all languages are related.

Based on what the genomics data indicate about the geographic divergence of early human populations. So we can say with a fair amount of certainty that the first split occurred about 135,000 years ago, so human language capacity must have been present by then, or before.

The paper based on this argument, "Linguistic capacity was present in the Homo sapiens population 135 ...," appears in Frontiers in Psychology.

Part 1

The new paper examines 15 genetic studies of different varieties, published over the past 18 years: three used data about the inherited Y chromosome, three examined mitochondrial DNA, and nine were whole-genome studies.

All told, the data from these studies suggest an initial regional branching of humans about 135,000 years ago. That is, after the emergence of Homo sapiens, groups of people subsequently moved apart geographically, and some resulting genetic variations have developed, over time, among the different regional subpopulations.

The amount of genetic variation shown in the studies allows researchers to estimate the point in time at which Homo sapiens was still one regionally undivided group.
The studies collectively provide increasingly converging evidence about when these geographic splits started taking place.

The first survey of this type was performed by other scholars in 2017, but they had fewer existing genetic studies to draw upon. Now, there are much more published data available, which, when considered together, points to 135,000 years ago as the likely time of the first split.
This new meta-analysis was possible because quantity-wise we have more studies, and quality-wise, it's a narrower window [of time].
Many linguists think all human languages are demonstrably related to each other.
Part 2

Some scholars have proposed that language capacity dates back a couple of million years, based on the physiological characteristics of other primates. But to the researchers of this study, the question is not when primates could utter certain sounds; it is when humans had the cognitive ability to develop language as we know it, combining vocabulary and grammar into a system generating an infinite amount of rules-based expression.
Human language is qualitatively different because there are two things, words and syntax, working together to create this very complex system. No other animal has a parallel structure in their communication system. And that gives us the ability to generate very sophisticated thoughts and to communicate them to others, they argue.
This conception of human language origins also holds that humans had the cognitive capacity for language for some period of time before we constructed our first languages.

Language is both a cognitive system and a communication system. Prior to 135,000 years ago, it did start out as a private cognitive system, but relatively quickly that turned into a communications system.
So, how can we know when distinctively human language was first used? The archaeological record is invaluable in this regard. Roughly 100,000 years ago, the evidence shows, there was a widespread appearance of symbolic activity, from meaningful markings on objects to the use of fire to produce ocher, a decorative red color.
Like our complex, highly generative language, these symbolic activities are engaged in by people, and no other creatures. As the paper notes, "behaviors compatible with language and the consistent exercise of symbolic thinking are detectable only in the archaeological record of H. sapiens.
So Language was the trigger for modern human behavior. Somehow, it stimulated human thinking and helped create these kinds of behaviors. If we are right, people were learning from each other [due to language] and encouraging innovations of the types we saw 100,000 years ago.
To be sure, as the authors acknowledge in the paper, other scholars think there was a more incremental and broad-based development of new activities around 100,000 years ago, involving materials, tools, and social coordination, with language playing a role in this, but not necessarily being the central force.

Shigeru Miyagawa et al, Linguistic capacity was present in the Homo sapiens population 135 thousand years ago, Frontiers in Psychology (2025). DOI: 10.3389/fpsyg.2025.1503900

Part 3

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Cancer's hidden messengers: How extracellular vesicles aid tumor spread

In recent years, extracellular vesicles have attracted attention as a carrier of intercellular signaling.

Most cells in the body send out little messengers called extracellular vesicles that carry proteins, lipids, and other bioactive molecules to other cells, playing an important role in intercellular communication. But healthy cells are not the only ones that rely on extracellular vesicles. Cancer cells do, too. Small extracellular vesicles that are shed from tumor cells contribute to how cancer spreads to healthy tissue.

These small messengers could be a key to developing new cancer-fighting drugs and therapies, but it has been unclear how exactly the recipient cells absorb the extracellular vesicles and their cargo. Recent research used state-of-the-art imaging to observe the uptake of tumor-derived small extracellular vesicles by target cells. The results were published in Nature Communications on March 12, 2025.

Researchers focused on small extracellular vesicles derived from two different tumor cell lines. Using single-particle imaging with single-molecule detection sensitivity, a high-tech imaging technique, they were able to categorize the small extracellular vesicles into distinct subtypes. They then tracked the internalization pathway of the extracellular vesicles, or how the vesicles were absorbed into their recipient cells.

Most small extracellular vesicles were internalized into their target cells through a process called endocytosis. Previously, researchers suspected that the primary mechanism was fusion. During endocytosis, the target cell's membrane completely surrounds the extracellular vesicle, creating a kind of bubble around the vesicle. This allows it to be absorbed through the membrane so its cargo can be deposited into the target cell.

Part 1

Researchers did not observe any instances of fusion, where the membrane of the cell and the membrane of the extracellular vesicle fuse together until the vesicle can enter the target cell.

Typically, endocytosis is facilitated with a protein called clathrin, but clathrin was not involved in the absorption of small extracellular vesicles into their target cells. Instead, it was a pair of proteins called galectin-3 and LAMP-2C, which are found on the membrane surface of the small extracellular vesicles.
The findings revealed that extracellular vesicles derived from several cancer cells are categorized into distinct subtypes.
All the subtypes of extracellular vesicles were primarily internalized by clathrin-independent endocytosis via galectin-3, which was facilitated by an increase in intracellular calcium concentration induced by the binding of extracellular vesicles to the target cells.
This process where a cell secretes a protein that aids in the absorption into a recipient cell from a different cell line is called paracrine binding or paracrine adhesion signaling. It is in contrast to an autocrine binding, which would be a cell secreting a protein so that it can bind to cells from the same cell line.

By better understanding the process by which small extracellular vesicles are brought into target cells, researchers are hopeful that the vesicles could be used to modify recipient cells and develop new cancer-fighting drugs.

Koichiro M. Hirosawa et al, Uptake of small extracellular vesicles by recipient cells is facilitated by paracrine adhesion signaling, Nature Communications (2025). DOI: 10.1038/s41467-025-57617-9

Part 2

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Preventing freezer bottle explosions: New insights into ice crystallization and pressure

Have you ever left a bottle of liquid in the freezer, only to find it cracked or shattered? To save you from tedious freezer cleanups, researchers at the University of Amsterdam have investigated why this happens, and how to prevent it. They discovered that while the liquid is freezing, pockets of liquid can get trapped inside the ice. When these pockets eventually freeze, the sudden expansion creates extreme pressure—enough to break glass.

The usual explanation for frost damage is that water expands when it freezes, but this does not explain why half-filled bottles also burst in our freezers. This new work addresses how ice can break a bottle even when it has plenty of space to expand into. Part 1

To understand this process, the researchers used a special dye, methylene blue, to track freezing in open cylindrical glass containers. The dye easily dissolves in water and turns it blue. The dye becomes transparent when the water freezes, as it gets pushed out of the ice crystals. This allows the researchers to see exactly when and where ice forms.

Having filmed tens of samples of blue-dyed water freezing in a—30°C environment, the researchers cracked the case. Ice breaks glass when the top surface of the water—the one open to air—freezes first. The rest of the water naturally freezes from the outside in, creating a pocket of liquid water surrounded by ice on all sides. When this pocket freezes too, it exerts an extreme amount of pressure on its surroundings, in many cases enough to break glass.
The researchers estimate the pressure exerted by the ice in their experiments to be around 260 megapascals, enough to dent high-strength steel and four times as much as their glass vials can withstand.
By testing glass containers of different sizes and with different surface coatings, the research team discovered that there are two ways to reduce the risk of trapped pockets of water forming.

The first way is to ensure the water gets colder before it begins to freeze. While water can start freezing at 0°C, it is possible for liquid water to get "supercooled" to subzero temperatures. Freezing needs to start somewhere, and the start of the phase transition can be delayed.

Supercooled water freezes differently than water that freezes closer to the freezing point. Rather than growing as a crystalline block, it freezes along fingerlike branches ("dendrites"). In the experiments, this type of freezing turns the dyed water a darker shade of blue before it freezes completely.

The researchers discovered that this unusual ice growth results in a large amount of small air bubbles getting trapped within the ice, something which appears to relieve enough pressure to prevent fracturing.
Part 2

Supercooling and the subsequent bubble formation were seen more often in narrower bottles. Comparing two bottles of different sizes filled with the same amount of water, the water in the smaller bottle cools down faster thanks to the larger surface it has per unit volume. This increases the chance of water cooling further below 0°C before it starts to freeze.
The second way to prevent trapped liquid pockets is to make sure that not the top surface, but the bottom of the container freezes first. So long as the top surface doesn't freeze over before the rest of the water does, the ice will simply expand into the open space above.
The team found that the shape of the water's surface plays a key role. In untreated glass containers, and in those coated with a layer that attracts water (being hydrophyilic), the water surface curves up against the glass. Thanks to the water molecules at the edge having less freedom to move, this region tends to be the first to freeze.

Water in containers with water-repelling (hydrophobic) coatings instead has a flat surface. Thanks to this, it is much more likely to freeze from the bottom up, preventing trapped liquid pockets from forming and reducing the risk of breakage.
If you don't want shattered bottles in your freezer, choose smaller bottles and ones with more water-repelling surfaces. (Many plastics are more water-repelling than glass—think of the PET bottles that many soft drinks come in, or of hard plastic like the PP used for Dopper bottles.) Beyond avoiding messy kitchen disasters, these new findings will also help with understanding and preventing frost damage in other places, including buildings, roads and historical artifacts.
But I don't recommend plastic bottles at all! This is not  good advice!

Menno Demmenie et al, Damage due to ice crystallization, Scientific Reports (2025). DOI: 10.1038/s41598-025-86117-5

Part 3

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East Asian human gene that allows adult humans to digest sugars in milk likely came from Neanderthals

A small team of computational and evolutionary biologists  reports that unique lactase genes carried by about 25% of East Asian people may have been inherited from Neanderthals.

In their study published in Proceedings of the National Academy of Sciences, the group compared the genes of thousands of people of African, East Asian and European descent against one another and then against Neanderthal genes.

Prior research has shown that many people of European descent carry genes that allow them to easily digest the sugars (lactose) present in milk, in sharp contrast to people of East Asian descent, who tend to have a high percentage of lactose intolerance.

However, in this new effort, the research team found unique versions of the lactase gene in some East Asian people along with evidence that they may have come from interbreeding between humans and Neanderthals thousands of years ago.

The researchers compared thousands of genomes collected from people of known European, African or East Asian descent, looking for commonalities between people who were lactose intolerant and those who were not. They found that approximately 25% of the East Asian samples studied carried versions of lactase genes not found in the genes of African or European people.

That led them to then compare those lactase genes from East Asians with genes from Neanderthals. They found that the genes in the East Asian samples likely came from the Neanderthals. This was because the genes showed up in the early humans before they had begun to drink the milk of domesticated animals such as cows, which ruled that out as a source of selection.

Exploring how the Neanderthals might have developed the lactase genes, the team found evidence that they may have provided some degree of protection against infections, a finding that would also explain why the genes persisted in East Asians long after the disappearance of the Neanderthal.

Xixian Ma et al, Neanderthal adaptive introgression shaped LCT enhancer region diversity without linking to lactase persistence in East Asian populations, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2404393122

Lakes worldwide are changing color, possibly due to human impact

Over the last 40 years, the majority of the world's lakes have changed color, according to a new study. The research team analyzed 32 million satellite observations from over 67,000 lakes. Major changes in the lake ecosystems are thought to be the cause.

Lakes are critical components of Earth's ecosystem. They provide habitats for aquatic and terrestrial species, support biodiversity and help maintain ecological balance. Lakes are also crucial for providing drinking water, supporting agriculture and influencing the climate through their effects on temperature, humidity and atmospheric processes.

The color of lakes is an important indicator of how healthy they are. Different shades reveal the ecological state of lakes and the ongoing physical and biochemical processes.

In a study published in Water Resources Research, a team of researchers analyzed 32 million satellite images of over 67,000 lakes from 1984 onwards.

After cross-checking with climate and population data, the researchers found that only 14% of the lakes studied maintained stable colors over time. The fact that so many lakes have changed color indicates significant ecosystem disruption caused by changes in water quality, algae concentrations, the flux of dissolved organic matter, and other contributing factors.

The results show the strong correlation between changes in lake colors, climate change and human impact. 

Lakes have different colors depending on where they are located. Blue lakes are primarily located in areas at northern latitudes, while green lakes are more prevalent in densely populated mid-latitude regions, such as southern Europe. Reddish and yellowish lakes are mainly found in the Southern Hemisphere.

In the study, the researchers found that most of the lakes have shifted toward shorter wavelengths (toward blue) over the last 40 years. A lake with a bluer color generally indicates clearer water and may reflect a healthier ecological state, although this will vary depending on the natural characteristics of the lake and its surroundings.

However, significant changes in lake color can signal ecological disturbances, such as increased nutrient loads or other drivers affecting the physical and biochemical properties of lake water. The differences between regions were remarkable.

Lakes in high-latitude regions, such as North America and northern Europe, showed a more pronounced change in color compared with those at the Equator and in the Southern Hemisphere. We don't really know why this is the case. This regional variation suggests that climate change and human activity are impacting ecosystems in complex and localized ways.

By mapping lake colors globally, the new study highlights how climate change and human activity are affecting lake ecosystems, which in turn have a major impact on food production, water supply and recreation. Understanding these changes can help communities and policymakers make informed decisions about water resource management, conservation and environmental protection.

Xiaoyi Shen et al, Satellite Observations Reveal Widespread Color Variations in Global Lakes Since the 1980s, Water Resources Research (2024). DOI: 10.1029/2023WR036926

Climate change 'will accelerate' owing to decline in natural carbon storage, says study

The natural process of locking away carbon dioxide (CO₂) appears to be in decline—and climate change will accelerate as a result, a new study warns.

Researchers found that the levels of CO2 retained in vegetation through this process, which is known as sequestration, had been increasing at 0.8% per year in the 1960s, but peaked in 2008 and are now falling at 0.25% per year.

If its growth rate of the 1960s had continued, natural sequestration would have increased by 50% from 1960 to 2010, but if its current rate of decline continues, it will have reduced by half in 250 years.

Sequestration offsets some of the emissions generated by human activity, which have recently been increasing by around 1.2% a year. Canceling this out would require these emissions to fall by 0.3% annually—equivalent to around 100 million tons of CO₂.

The study is published in the journal Weather.

James C. Curran et al, Natural sequestration of carbon dioxide is in decline: climate change will accelerate, Weather (2025). DOI: 10.1002/wea.7668

Slow, silent 'scream' of epithelial cells detected for first time

It has long been thought that only nerve and heart cells use electric impulses to communicate, while epithelial cells—which compose the linings of our skin, organs and body cavities—are mute, serving mostly as protective barriers that can absorb and secrete various substances.

But  researchers  have upended the status quo by showing that epithelial cells do indeed "talk" to each other, albeit with slow electrical signals.

 The discovery, published in the Proceedings of the National Academy of Sciences, could enable new applications for everything from wearable bioelectric sensors to wound healing.

Epithelial cells do things that no one has ever thought to look for. When injured, they 'scream' to their neighbors, slowly, persistently and over surprising distances. It's like a nerve's impulse, but 1,000 times slower. 

The researchers' curiosity-driven approach, blending polymer science and biology, unveiled this hidden cellular signaling.

They used an epithelial-cell-coated chip with 60 precisely placed electrodes to eavesdrop. They grew a single layer of human epithelial cells on the chip, which detected minute electric shifts.

Using a precise laser to produce "sting" patterns of individual cells, they watched as signals rippled outward. They tracked how cells coordinated their response. "It's a slow-motion, excited conversation."

Unlike the swift neurotransmitter bursts of nerve cells, epithelial cells rely on ion flows—of calcium, especially—that produce signals that are far slower than those in nerve cells, but with similar voltages. These signals can be long-lived: The researchers observed cells that "talked" for over five hours across distances nearly 40 times their own length.

They showed that calcium ions are necessary for epithelial conversation, they have yet to test what else might contribute to the conversation. And though the immediate applications of their new discovery remain to be seen, the implications are vast. Wearable sensors, implantable devices and faster wound healing could grow from this .

Granick, Steve, Electric spiking activity in epithelial cells, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2427123122. doi.org/10.1073/pnas.2427123122

Mimicry: Baby birds behaving like caterpillars to escape predators

Even hummingbird chick acts like a caterpillar to survive

Even hummingbird chick acts like a caterpillar to survive

Jay J. Falk et al, Potential caterpillar mimicry in a tropical hummingbird, Ecology (2025). DOI: 10.1002/ecy.70060

Kids under eight shouldn't drink slushies, researchers warn

Children under eight should not drink slushy ice drinks containing glycerol, researchers have warned after a string of hospitalizations in the UK and Ireland.

The brightly colored drinks marketed towards children often use glycerol as a sweetener and anti-freezing agent. But high levels can be harmful, especially to children—glycerol intoxication can cause shock, low blood sugar and loss of consciousness.

In a peer-reviewed medical review published in the Archives of Disease in Childhood journal this week, researchers looked into a "recent apparent surge in cases" in the UK and Ireland, and suggested children under eight should avoid the drinks entirely. They studied the medical records of 21 children aged two to seven who needed emergency treatment after drinking slushies.

Most cases took place between 2018 and 2024 and many of the children became acutely ill within an hour, the researchers said. Most of the children lost consciousness and showed signs of high blood acidity and low sugar, while four needed brain scans and one had a seizure.

The children all recovered swiftly, the researchers said.

Food safety agencies in the two countries already advise that children aged four and under should not have slushies containing glycerol.

But the researchers said the age should be raised further.

"Younger children, especially those under eight years of age, should avoid slush ice drinks containing glycerol," they said.

"Clinicians and parents should be alert to the phenomenon, and public health bodies should ensure clear messaging."

The review's authors also said there could be cases where children have suffered less serious illness and not been taken to hospital.

 Glycerol intoxication syndrome in young children, following the consumption of slush ice drinks, Archives of Disease in Childhood (2025). DOI: 10.1136/archdischild-2024-328109

Discovery shows how cells use telomeres to avoid cancer

Cancer researchers at Children's Medical Research Institute have discovered an "unexpected mechanism" that our cells use to avoid cancer.

Telomeres are the protective caps at chromosome ends and are involved in aging and cancer. As we age, telomere length naturally decreases. Over the course of a lifetime, telomere shortening instructs aging cells to stop dividing. This normally functions as a critical barrier to stop cancer.

Most people think of telomeres as a passive entity that shorten with cell division; this is a passive fail-safe used during aging.

The new  data shows telomeres are much more active. They can acutely respond to stress and actively open up to turn on a cellular response that looks like aging. They do this to avoid cancer.

This can lead to cell cycle arrest, or death, to prevent these damaged cells with chromosome errors from dividing further. This suggests telomeres have another anti-cancer mechanism that was previously unknown.

Diana Romero-Zamora et al, A CPC-shelterin-BTR axis regulates mitotic telomere deprotection, Nature Communications (2025). DOI: 10.1038/s41467-025-57456-8

Antibiotic-resistant bacteria more vulnerable under body-like fluid flow conditions, study finds

Some notoriously difficult-to-treat infections may not be as resistant to antibiotics as has been thought, according to new research using a microfluidic device that more closely duplicates the fluid flow found in the body than standard cultures.

Researchers tested antibiotic agents against Pseudomonas aeruginosa, considered one of the most highly resistant pathogens. They introduced the drugs at varying rates of fluid flow and found that, while the bacteria thrived at no or low fluid flow, the antibiotics killed the bacteria at higher flow rates.

Anytime you take an antibiotic orally or by IV, it's not immediately in the place it is supposed to be. It will get there by flowing in the bloodstream. Other fluids move throughout the body as well: in the lungs, the urinary tract, the digestive tract.

So it is important to know the impact of fluid flow. By using the microfluidic technology, often used in engineering, in a biology setting, the researchers found that fluid flow is very important for antibiotic activity. 

Whether in a biology lab or a clinical lab, the standard way to study pathogenic bacteria is in plates, tubes or wells—settings not representative of the dynamics found in the body. The microfluidic devices the present group used allow for precise control of the rate of fluid flowing.

The researchers tested three different antibiotic agents against which the Pseudomonas was supposedly resistant. They saw a gradient of antibiotic activity that was dependent on the flow rate. At no to low flow, the antibiotics affected only the bacteria at the very start of the fluid track. As the flow rate increased, so did the reach of the antibiotic activity, until the entire culture sample was wiped out at the highest tested flow rates.

The findings highlight how we could do a better job of characterizing antibiotic resistance. If you get an infection, a clinician might take a sample and test it to see which drugs will work against it. But they're testing it without flow. So they may not give you a drug that actually could be effective because their tests don't show how effective the drugs are in flow conditions like in the body.

  When researchers try to develop a new drug, it's the same thing; they might be wrong in interpreting whether the drug is working or not, because the testing conditions aren't like the body.

Next, the research team plans to test other antibiotic-resistant pathogens and other antibiotic drugs in their microfluidic devices. They also hope to more deeply study the mechanisms behind why the antibiotics were more effective in flowing fluid.

That is why I wrote several times that lab conditions will be different from actual conditions. Several factors affect the outcomes and until we test all of them, we cannot say our results are hundred percent correct.

 Alexander M. Shuppara et al, Shear flow patterns antimicrobial gradients across bacterial populations, Science Advances (2025). DOI: 10.1126/sciadv.ads5005

 The mysterious 'red sprite' lightning strikes over the Himalayas

Have you ever heard of—or even seen—red lightning? These are not animated characters but real atmospheric phenomena known as electrical discharges that occur high above thunderstorms. Scientists refer to them as "red sprites," named for their jellyfish-like appearance and vivid red flashes. Now, imagine witnessing these mesmerizing displays over the world's highest mountain range—the Himalayas.

On the night of May 19, 2022, two Chinese astrophotographers, Angel An and Shuchang Dong, captured a spectacular display of over one hundred red sprites over the Himalayas. The observation site, located on the southern Tibetan Plateau near Pumoyongcuo Lake—one of the region's three sacred lakes—revealed a breathtaking celestial event.

Among the phenomena captured were dancing sprites, rare secondary jets, and the first-ever recorded case in Asia of green airglow at the base of the nighttime ionosphere, dubbed "ghost sprites." This extraordinary event attracted global attention and was widely covered by major media outlets.

A recent study published in Advances in Atmospheric Sciences by Professor Gaopeng Lu and his team at the University of Science and Technology of China sheds light on the driving force behind this grand "sprite fireworks"—lightning and thunderstorms.

By analyzing the parent lightning discharges, they discovered that the sprites were triggered by high-peak current positive cloud-to-ground lightning strikes within a massive mesoscale convective system. This suggests that thunderstorms in the Himalayan region have the potential to produce some of the most complex and intense upper-atmospheric electrical discharges on Earth.

Lacking precise timestamps for detailed analysis, the research team developed an innovative method to synchronize video time using satellite trajectories and star field analysis. This innovative approach allowed them to determine the exact occurrence times of the sprites and link them to their parent lightning discharges. One of the anonymous reviewers praised the technique, highlighting its potential as a reliable timing tool for citizen scientists contributing to scientific observations.
The study revealed that the parent lightning discharges occurred within stratiform precipitation regions of a mesoscale convective complex stretching from the Ganges Plain to the southern foothills of the Tibetan Plateau. This event recorded the highest number of sprites during a single thunderstorm in South Asia, suggesting that thunderstorms in this region possess upper-atmospheric discharge capabilities comparable to those in the U.S. Great Plains and offshore European storms.

Moreover, the findings indicate that these storms may generate even more complex discharge structures, potentially influencing atmospheric coupling processes with significant physical and chemical effects.

Hailiang Huang et al, Massive Outbreak of Red Sprites in South Asia Observed from the Tibetan Plateau, Advances in Atmospheric Sciences (2025). DOI: 10.1007/s00376-024-4143-5

Genetic study reveals hidden chapter in human evolution

Modern humans descended from not one, but at least two ancestral populations that drifted apart and later reconnected, long before modern humans spread across the globe.

Using advanced analysis based on full genome sequences, researchers  have found evidence that modern humans are the result of a genetic mixing event between two ancient populations that diverged around 1.5 million years ago. About 300,000 years ago, these groups came back together, with one group contributing 80% of the genetic makeup of modern humans and the other contributing 20%.

For the last two decades, the prevailing view in human evolutionary genetics has been that Homo sapiens first appeared in Africa around 200,000 to 300,000 years ago, and descended from a single lineage. However, these latest results, reported in the journal Nature Genetics, suggest a more complex story.

For a long time, it's been assumed that we evolved from a single continuous ancestral lineage, but the exact details of our origins are uncertain. 

This new  research work  shows clear signs that our evolutionary origins are more complex, involving different groups that developed separately for more than a million years, then came back to form the modern human species.

While earlier research has already shown that Neanderthals and Denisovans—two now-extinct human relatives—interbred with Homo sapiens around 50,000 years ago, this new research suggests that long before those interactions—around 300,000 years ago—a much more substantial genetic mixing took place.

Unlike Neanderthal DNA, which makes up roughly 2% of the genome of non-African modern humans, this ancient mixing event contributed as much as 10 times that amount and is found in all modern humans.

The team's method relied on analyzing modern human DNA, rather than extracting genetic material from ancient bones, and enabled them to infer the presence of ancestral populations that may have otherwise left no physical trace. The data used in the study are from the 1000 Genomes Project, a global initiative that sequenced DNA from populations across Africa, Asia, Europe, and the Americas.
The team developed a computational algorithm called cobraa that models how ancient human populations split apart and later merged back together. They tested the algorithm using simulated data and applied it to real human genetic data from the 1000 Genomes Project.

While the researchers were able to identify these two ancestral populations, they also identified some striking changes that happened after the two populations initially broke apart.
Part 1

Immediately after the two ancestral populations split, we see a severe bottleneck in one of them—suggesting it shrank to a very small size before slowly growing over a period of one million years.
This population would later contribute about 80% of the genetic material of modern humans, and also seems to have been the ancestral population from which Neanderthals and Denisovans diverged.
However, some of the genes from the population which contributed a minority of our genetic material, particularly those related to brain function and neural processing, may have played a crucial role in human evolution.
The study also found that genes inherited from the second population were often located away from regions of the genome linked to gene functions, suggesting that they may have been less compatible with the majority genetic background. This hints at a process known as purifying selection, where natural selection removes harmful mutations over time.
The fact that we can reconstruct events from hundreds of thousands or millions of years ago just by looking at DNA today is astonishing.

A structured coalescent model reveals deep ancestral structure shared by all modern humans, Nature Genetics (2025). DOI: 10.1038/s41588-025-02117-1

Part 2

Scientists see the first steps of DNA unwinding

For the first time, scientists have witnessed the very moment DNA begins to unravel, revealing a necessary molecular event for DNA to be the molecule that codes all life.

A new study published in Nature, captures the moment DNA begins to unwind, allowing for all the events that follow in DNA replication.

This direct observation sheds light on the fundamental mechanisms that allow cells to faithfully duplicate their genetic material, a cornerstone for growth and reproduction.

Using cryo-electron microscopy and deep learning to observe the helicase Simian Virus 40 Large Tumor Antigen interacting with DNA, the work  provides the most detailed description yet of the very first steps of DNA replication: 15 atomic states that describe how the enzyme helicase forces the unwinding of DNA.

The achievement is not only a milestone in helicase research, but also a milestone in observing the dynamics of any enzyme at atomic resolution.

 For DNA to replicate, the helix must first unwind and break the DNA from a double strand into two single strands.

Upon binding, helicases melt the DNA, breaking the chemical bonds holding the double helix together. They then pull the two strands apart, allowing other enzymes to complete the replication. Without this first step, no DNA can be replicated. In this way, helicases are machines or, because of their size, nanomachines.

Part 1

If helicases are nanomachines, then "ATP," or adenosine trisphosphate, is the fuel. Much like how burning gas drives the pistons of a car engine, burning ATP, the same fuel used to flex your muscles, causes the six pistons of a helicase to unwind DNA.

The study found that as ATP is consumed, it reduces physical constraints that allow the helicase to proceed along the DNA, unwinding more and more of the double strand. Thus, ATP consumption acts as a switch that increases the amount of entropy—or disorder—in the system, freeing the helicase to move along the DNA.
The helicase uses ATP not to pry DNA apart in one motion, but to cycle through conformational changes that progressively destabilize and separate the strands. ATP burning, or hydrolysis, functions like the spring in a mouse trap, snapping the helicase forward and pulling the DNA strands apart.
Among the many discoveries made by the scientists was that two helicases melt the DNA at two sites at the same time to initiate the unwinding. The chemistry of DNA is such that nanomachines move along a single DNA strand in one direction only. By binding at two sites simultaneously, the helicases coordinate so that the winding can happen in both directions with an energy efficiency unique to natural nanomachines.

 Taha Shahid et al, Structural dynamics of DNA unwinding by a replicative helicase, Nature (2025). DOI: 10.1038/s41586-025-08766-w. www.nature.com/articles/s41586-025-08766-w

Part 2

Trees awaken to spring at their own pace—even within the same species in the same forest

Climatic stress events, such as extreme temperatures and prolonged droughts, are increasingly affecting tree growth and phenology—the timing of developmental stages like leaf burst and senescence.

To better understand these processes, researchers set up a long-term experiment with a permanent laser scanning station located at SMEAR II research station.

 The findings are published in the journal Agricultural and Forest Meteorology.

The scanner uses laser light to create centimeter-precise 3D models of individual trees, enabling scientists to track growth and structural changes with unprecedented detail.

Laser scanning time series enable the observation of tree changes over time without interfering with their natural growth. For the first time, scientists were able to accurately measure day-level differences in the phenology of trees in an automated manner. Subsequently, they could study the factors influencing and the effects of these phenological variations within one growth season.

The study focused on silver birch trees and found that species richness and competitive pressure for light in the immediate vicinity influenced the timing of spring leaf burst, while water availability shaped the timing of fall leaf senescence. Additionally, the timing of growth proved critical; for example, early leaf burst was linked to increased crown area growth later in the season. There was a difference of up to 12 days in the time when leaf senescence occurred in the observed trees.

This research highlights how individual trees differ in the timing and duration of their growth period due to the local growth environment, even in a relatively small and homogenous forest area. These insights, like the impact of local water availability on leaf senescence, also help us to understand how changing climate impacts tree phenology and growth within a forest stand.

The experiment provides a better understanding of how local factors drive tree growth.

Mariana Batista Campos et al, Factors and effects of inter-individual variability in silver birch phenology using dense LiDAR time-series, Agricultural and Forest Meteorology (2024). DOI: 10.1016/j.agrformet.2024.110253

Experimental antifungal compound kills multidrug-resistant fungi

The discovery of a new preclinical compound with strong antifungal activity against multidrug-resistant pathogens is described in Nature. The drug, named mandimycin, is a member of a known family of bacterial products with antifungal properties, the polyene macrolides. Unlike known compounds in this family, mandimycin binds to a novel target in the fungal cell membrane and is therefore active against a range of pathogens that are resistant to related compounds.

Mandimycin, does not bind to ergosterol in the cell membrane, the typical target of polyene macrolides. Instead, mandimycin was shown to bind various phospholipids in the fungal cell membrane. This mode of action means that it is effective against fungal pathogens that have evolved resistance to existing antifungal agents that target ergosterol, such as the clinically used agent amphotericin B.

The authors used animal models of infection to test mandimycin against a range of fungal pathogens, including multidrug-resistant Candida auris (a species listed as a priority fungal threat by the WHO), and found that the compound had increased efficacy and reduced nephrotoxicity, as compared with amphotericin B.

Zongqiang Wang, A polyene macrolide targeting phospholipids in the fungal cell membrane, Nature (2025). DOI: 10.1038/s41586-025-08678-9. www.nature.com/articles/s41586-025-08678-9

Probiotic boosters shorten fever duration in pediatric trial

A clinical trial  by researchers found a probiotic mixture that significantly shortened fever duration in children with upper respiratory tract infections (URTIs). Children who received a probiotic mixture containing Bifidobacterium breve M-16V, Bifidobacterium lactis HN019, and Lactobacillus rhamnosus HN001 experienced a median fever reduction of two days compared to those given a placebo.

The research is published in the journal JAMA Network Open.

Upper respiratory tract infections are among the most common illnesses affecting young children. Reports indicate that children typically experience five to eight URTIs per year, particularly in the first five years of life. Fever is a frequent symptom and a leading cause of health care visits, often contributing to inappropriate antibiotic use. Antibiotics provide no benefit for viral infections, which account for the majority of cases.

Current symptom management through antipyretics, such as acetaminophen (paracetamol), can temporarily lower body temperature without reducing fever duration. Probiotics have shown potential in modulating immune responses, yet limited clinical evidence exists regarding their role in treating respiratory infections in children.

In the study titled "Probiotics and Fever Duration in Children With Upper Respiratory Tract Infections: A Randomized Clinical Trial," researchers conducted a triple-blind, placebo-controlled randomized clinical trial to evaluate whether a probiotic mixture could reduce fever duration in children with URTIs.

Primary outcome focused on fever duration, defined as the number of days between the first and last recorded febrile day. Secondary outcomes included antibiotic prescription rates after discharge and the incidence of antibiotic-associated diarrhea. Fever duration was recorded by caregivers, with follow-up conducted via telephone to assess compliance and adverse events.

Results indicated that children in the probiotic group experienced a significantly shorter fever duration than those in the placebo group. The median fever duration was 3 days in the probiotic group compared to 5 days in the placebo group.

Poisson regression analysis, adjusted for age, sex, and antibiotic intake, demonstrated that probiotic supplementation was associated with a fever duration risk ratio of 0.64. Adverse events, including constipation and abdominal pain, were infrequent and similar between both groups. No significant effects were observed on antibiotic prescription rates or the incidence of antibiotic-associated diarrhea, and no meaningful safety concerns were identified.

Authors acknowledge the limitations, including the single-center design and reliance on caregiver-reported temperature measurements. The trial did not distinguish between bacterial and viral URTIs, and participants may have received the probiotic at different stages of illness.

Investigators noted that while previous studies on probiotics have primarily focused on prevention rather than treatment, this trial provides evidence supporting their potential therapeutic role as an adjunct treatment for pediatric URTIs.

Silvia Bettocchi et al, Probiotics and Fever Duration in Children With Upper Respiratory Tract Infections, JAMA Network Open (2025). DOI: 10.1001/jamanetworkopen.2025.0669

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Dark energy seems to be changing

Dark energy, the mysterious force thought to be driving the ever-faster expansion of the universe, appears to be changing over time, according to new observations released this week.

If dark energy is in fact weakening, it would likely mean that science's understanding of how the universe works will need to be rewritten.

The new findings come from the Dark Energy Spectroscopic Instrument (DESI), which sits on a telescope at the Kitt Peak National Observatory in the U.S. state of Arizona.

What we are seeing now is deeply intriguing, say the scientists. It is exciting to think that we may be on the cusp of a major discovery about dark energy and the fundamental nature of our universe.

The DESI instrument's thin optical fibers can simultaneously observe 5,000 galaxies or quasars—blazing monsters with a black hole at their heart—for 20 minutes.

This allows scientists to calculate the age and distance of these objects, and create a map of the universe so they can detect patterns and trace its history.

Scientists have known for a century that the universe is expanding, because massive clusters of galaxies have been observed moving away from each other.

In the late 1990s, scientists shocked the field by discovering that the universe's expansion has been speeding up over time.

The name dark energy was given to the phenomenon driving this acceleration, the effects of which seem to be partially offset by ordinary matter—and an also unknown thing called dark matter.

The universe is thought to be made of 70% dark energy, 25% dark matter—and just 5% normal matter.

Science's best understanding of how the universe works, which is called the standard cosmological model, refers to dark energy as being constant—meaning it does not change.

The idea was first introduced by Albert Einstein in his theory of relativity.

Part 1

Now some physicists are saying, 'the standard model is "satisfactory" but some "tensions" are emerging between observations'.

There are several different ways of measuring the expansion of the universe, including looking at the lingering radiation from after the Big Bang, exploding stars called supernovae and how gravity distorts the light of galaxies.

When the DESI team combined their new data with other measurements, they found "signs that the impact of dark energy may be weakening over time," according to a statement.
When we combine all the cosmological data, it favors that the universe's expansion was accelerating at a slightly higher rate around seven billion years ago
But for the moment there is "absolutely not certainty" about this.
Scientists are confident that "evolving dark energy" theory would be a "revolution on the level of the discovery of accelerated expansion,"
The standard cosmological model would have to be different.
The DESI research, which involved three years' worth of observations of 15 million galaxies and quasars, was presented at a conference of the American Physical Society in California.

https://summit.aps.org/events/APR-R08/1

Part 2

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Uniquely shaped, fast-heating nanoparticles halt ovarian tumor growth

New magnetic nanoparticles in the shape of a cube sandwiched between two pyramids represent a breakthrough for treating ovarian tumors and possibly other types of cancer, according to  researchers who developed them.

The scientists say the study underscores the importance of shape in magnetic nanoparticle design and that the findings will potentially revolutionize treatments that use heat to damage or kill cancer cells.

Made of iron oxide and doped with cobalt, the nanoparticles show exceptional heating efficiency when exposed to an alternating magnetic field. Doping refers to adding something as a means of tailoring characteristics.

When the particles accumulate in cancerous tissue after intravenous injection, they're able to quickly rise to temperatures that weaken or destroy cancer cells.

This is the first time systemically injected nanoparticles have been shown to heat tumors beyond 50° C, significantly surpassing the therapeutic threshold of 44° C for effective treatment at a clinically relevant dose.

Prem Singh et al, Precision‐Engineered Cobalt‐Doped Iron Oxide Nanoparticles: From Octahedron Seeds to Cubical Bipyramids for Enhanced Magnetic Hyperthermia, Advanced Functional Materials (2025). DOI: 10.1002/adfm.202414719

Even Galapagos birds are exhibiting 'road rage' due to noise!

A new study has discovered that birds in the Galápagos Islands are changing their behavior due to traffic noise, with those frequently exposed to vehicles showing heightened levels of aggression.

Published in the journal Animal Behaviour the research examined the impact of vehicle noise pollution on Galápagos yellow warblers (Setophaga petechia aureola), a songbird widespread on the archipelago.

The Galápagos Islands, located over 500 miles off the coast of Ecuador, are considered a natural living laboratory due to the large number of unique, endemic species. The Galápagos yellow warbler is genetically distinct from other yellow warblers found in the Americas and is classified as a subspecies.

A visit to the Galápagos Islands in 1835 helped inspire Charles Darwin to develop the theory of evolution by natural selection. However, recent decades have seen significant human population growth. Alongside a rise in tourism, the permanent population is increasing by over 6% per year, leading to more vehicles on the islands' roads.

The new study involved researchers playing bird songs from a speaker, simulating an intruder, accompanied by recorded traffic noise at 38 locations populated by Galápagos yellow warblers on the islands of Floreana and Santa Cruz—20 sites were within 50 meters of the nearest road and 18 were over 100 meters away.

The researchers then measured song, typically used to ward off intruders, and physical, aggressive behaviors such as approaching the speaker closely and making repeated flights across it.

During trials with traffic noise, the researchers found that Galápagos yellow warblers living in roadside territories showed increased aggression, but those living away from the roads showed decreased aggression relative to trials without noise.

Importantly, the effect of living on a roadside territory was present even on Floreana Island, with only about 10 vehicles present on the island, suggesting even minimal experience of traffic affects responses to noise.

Additionally, Galápagos yellow warblers on the more populous island of Santa Cruz increased the duration of their song when confronted by traffic noise. These findings support the idea that long-term selection based on noise experience, or an individual bird's previous experience of noise, allows them to adapt and adjust the features of their songs.

Finally, the birds increased the minimum frequencies of their songs during the noise experiments, regardless of their territory's proximity to the road, helping to reduce any overlap of their songs with the low-frequency traffic noise.

The  results show that the change in aggressive responses in yellow warblers occurred mainly near roads. Birds occupying roadside territories on both islands, and therefore having regular experience of traffic noise, may have learned to increase physical aggression when the territorial intrusion was accompanied by traffic noise.

The study shows the importance of considering behavioral plasticity in conservation efforts and developing strategies to mitigate the effects of noise pollution on wildlife. It also highlights the significant impact of human activities on wildlife behavior, even in relatively remote locations such as the Galápagos Islands.

Reference: 20 March 2025, Animal Behaviour.

Part of the genetic risk for schizophrenia acts through the placenta, research reveals

An international research team reveals the relationship between placental DNA methylation and certain neuropsychiatric disorders.

The  has identified associations between modifications in the placenta and the risk of developing schizophrenia, bipolar disorder, and major depressive disorder.

The study was published in Nature Communications.

The study, which involved 28 researchers from 18 institutions across Europe and the United States, highlights the placenta as a key element in neuropsychiatric development. The research has demonstrated that specific epigenetic modifications in the placenta, particularly DNA methylation, can influence the expression of genes associated with psychiatric disorders. These findings suggest that genetic risk may already manifest during the prenatal stage.

Epigenetic modifications are chemical changes in DNA and its associated proteins that regulate gene activity without altering their sequence. One of the most studied modifications is DNA methylation, a process in which methyl groups—small molecules composed of one carbon and three hydrogen atoms—are added to specific regions of the DNA.

This mechanism, essential for development, environmental adaptation, and disease predisposition, is influenced by genetics and responds to factors such as diet, stress, and exposure to pollutants.

The study results indicate that schizophrenia, bipolar disorder, and major depressive disorder are the neuropsychiatric disorders most strongly linked to DNA methylation in the placenta. Other conditions, such as attention deficit hyperactivity disorder (ADHD) or autism, show some potentially causal associations, although to a lesser extent, while no visible effects were found in other analyzed pathologies.

These findings reinforce the hypothesis that schizophrenia and other disorders have a neurodevelopmental origin and that the placenta plays a fundamental role in this process.

The discovery that genetic risk may be linked to placental DNA methylation opens new avenues for preventing and treating psychiatric disorders. If we could identify risk factors at the prenatal stage, we could intervene before symptoms appear, adjusting treatments or designing personalized preventive strategies, the researchers say.

This research represents a significant advance in understanding the biological basis of neuropsychiatric disorders and opens new lines of investigation for early detection, as well as for the development of more effective therapies.

Scientists witness living plant cells generate cellulose and form cell walls for the first time

In a groundbreaking study on the synthesis of cellulose—a major constituent of all plant cell walls—a team of researchers have captured images of the microscopic process of cell-wall building continuously over 24 hours with living plant cells, providing critical insights that may lead to the development of more robust plants for increased food and lower-cost biofuels production.

The discovery, published in the journal Science Advances, reveals a dynamic process never seen before and may provide practical applications for everyday products derived from plants, including enhanced textiles, biofuels, biodegradable plastics, and new medical products.

The research is also expected to contribute to the fundamental knowledge while providing a new understanding of the formation of cell walls, the scientists said.

This work is the first direct visualization of how cellulose synthesizes and self-assembles into a dense fibril network on a plant cell surface.

This study also provides entirely new insights into how simple, basic physical mechanisms such as diffusion and self-organization may lead to the formation of complex cellulose networks in cells.

The microscope-generated video images show protoplasts—cells with their walls removed—of cabbage's cousin, the flowering plant Arabidopsis, chaotically sprouting filaments of cellulose fibers that gradually self-assemble into a complex network on the outer cell surface.

Hyun Huh et al, Time-resolved tracking of cellulose biosynthesis and assembly during cell wall regeneration in live Arabidopsis protoplasts, Science Advances (2025). DOI: 10.1126/sciadv.ads6312. www.science.org/doi/10.1126/sciadv.ads6312

Deadly bacteria have developed the ability to produce antimicrobials and wipe out competitors, scientists discover

A drug-resistant type of bacteria that has adapted to health care settings evolved in the past several years to weaponize an antimicrobial genetic tool, eliminating its cousins and replacing them as the dominant strain. Scientists made this discovery when combing through local hospital data—and then confirmed that it was a global phenomenon.

The finding, published in Nature Microbiology, may be the impetus for new approaches in developing therapeutics against some of the world's deadliest bacteria.

After analyzing the genomic sequences of 710 VREfm infection samples from hospitalized patients entered into EDS-HAT over a six-year time span, researchers discovered that the variety of VREfm strains had shrunk from about eight fairly evenly distributed types in 2017 to two dominant strains that began to emerge in 2018 and, by the end of 2022, were the culprit in four out of every five patient VREfm samples.

Upon closer examination,  they found that the dominant strains had acquired the ability to produce a bacteriocin, which is an antimicrobial that bacteria use to kill or inhibit one another. They'd weaponized this new capability to destroy the other VREfm strains, giving them unfettered access to nutrients for easier reproduction.

They also observed that what had happened locally had also been happening on a global scale.

It does not appear that the bacteriocin-wielding VREfm are making patients any sicker than their predecessors did.

But it could point to potential avenues for the development of new therapies.

: 'Bacteriocin production facilitates nosocomial emergence of vancomycin-resistant Enterococcus faecium', Nature Microbiology (2025). DOI: 10.1038/s41564-025-01958-0

Boosting brain's waste removal system improves memory in old mice

As aging bodies decline, the brain loses the ability to cleanse itself of waste, a scenario that scientists think could be contributing to neurodegenerative conditions such as Alzheimer's disease and Parkinson's disease, among others.

Now, researchers  report they have found a way around that problem by targeting the network of vessels that drain waste from the brain. Rejuvenating those vessels, they have shown, improves memory in old mice.

The study,  published online in the journal Cell, lays the groundwork to develop therapies for age-related cognitive decline that overcome the challenges faced by conventional medications that struggle to pass through the blood-brain barrier to reach the brain.

The physical blood-brain barrier hinders the efficacy of therapies for neurological disorders. 

By targeting a network of vessels outside of the brain that is critical for brain health, we see cognitive improvements in mice, opening a window to develop more powerful therapies to prevent or delay cognitive decline, say the researchers.

 Kim K, et al. Meningeal lymphatics-microglia axis regulates synaptic physiology, Cell (2025). DOI: 10.1016/j.cell.2025.02.022. www.cell.com/cell/fulltext/S0092-8674(25)00210-7. www.cell.com/cell/fulltext/S0092-8674(25)00210-7