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Comment by Dr. Krishna Kumari Challa on September 26, 2025 at 8:50am

Camouflage or caution? How anti-predator strategies have evolved

Predators and the environment determine why some animals use camouflage to avoid being eaten, while others use bright colors to warn them off, new research reveals. Published recently  in the journal Science, the findings help explain the evolution and global distribution of the most common color strategies used by insects to avoid predators.

The global study took place across six continents and involved over 50 scientific collaborators.

Using the same experiment, researchers deployed more than 15,000 artificial prey with three different colors to investigate which strategy works best to deter predators: a classic warning pattern of orange and black, a dull brown that blends in, and an unusual bright blue and black.

The researchers found the answer to why some animals use camouflage over warning colors to deter predators turned out to be more complex than expected.

The findings showed there is no single best color strategy to deter predators, but that context is critical. The different characteristics of the predator and prey communities, as well as habitat in that part of the globe, heavily decide which strategy performs better in each place. This makes sense when we see animals employing so many varying camouflage and warning color strategies as defense systems all over the world.

Predators had the biggest influence on which color strategy was most successful for prey, the study revealed.

In environments where predators are competing intensely for food, they are more likely to risk attacking prey that might be dangerous or distasteful. Hence, the researchers saw that camouflage worked best in areas with lots of predation.

Whereas, in places where cryptic prey (insects who use camouflage) are abundant, hiding becomes less effective, as predators are better at looking for those types of animals.

The findings help scientists understand why some species, such as the cryptic bogong moth or the brightly colored harlequin bug, have evolved their strategies against predators.

 Iliana Medina et al, Global selection on insect antipredator coloration, Science (2025). DOI: 10.1126/science.adr7368. www.science.org/doi/10.1126/science.adr7368

Comment by Dr. Krishna Kumari Challa on September 26, 2025 at 8:40am

Scientists discover that cell nucleus is actually less dense than surrounding cytoplasm

Just as life pulsates in big vibrant cities, it also prospers in crowded environments inside cells. The interior of cells is densely packed with biomolecules like proteins and nucleic acids. How is all this material distributed within a cell and what regulates its distribution?

In a study published in Nature Communications, researchers measure subcellular densities across a wide range of organisms. Their aim is to better understand biomolecular processes ranging from yeast cells  to human cells.

Conventional scientific textbooks describe the cell nucleus as a compartment packed with an impressive amount of DNA wrapped around histone proteins.

Now, an international team of researchers has discovered that—contrary to expectations—the nucleus is less dense than the surrounding cytoplasm.

Despite their rich biomolecular composition, nuclei contain less dry mass than the same volume of the surrounding cytoplasm.

How can density be measured in microscopic objects such as individual cell compartments? Scientists use light for this purpose. Not only does light allow cells to be examined, it also enables them to be manipulated. Light can exert forces, enabling laser beams to "pull" on cells and measure their mechanical properties using an "optical stretcher."

The researchers developed an optical setup which allowed them to obtain three-dimensional density distributions inside cells at high resolution by combining optical diffraction tomography and confocal fluorescence microscopy.

While NC density ratios are maintained from yeast to human cells, we do start seeing deviations in disease. During stressed cellular states such as aging, the so-called senescence, cell nuclei become denser than the cytoplasm. Thus, the study points to the fundamental importance of density as a variable that determines healthy cellular processes, the researchers note in their paper.

 Abin Biswas et al, Conserved nucleocytoplasmic density homeostasis drives cellular organization across eukaryotes, Nature Communications (2025). DOI: 10.1038/s41467-025-62605-0

Comment by Dr. Krishna Kumari Challa on September 25, 2025 at 1:30pm

Lab-grown kidneys yield urine
Researchers have created the most sophisticated kidney organoid to date, offering a real shot at growing transplantable kidneys from stem cells. These mini kidneys were capable of making urine when transplanted into mice. “You wouldn’t mistake it for a real kidney,” says experimental anatomist Jamie Davies. “But it is trying to do the right things.” Plumbing — encouraging the organoid to develop blood vessels and the duct that carries urine to the bladder — is the major hold-up. The researchers estimate a transplantable kidney will be ready for animal testing in less than five years.

https://www.sciencedirect.com/science/article/abs/pii/S193459092500...

https://www.science.org/content/article/scientists-make-most-authen...

Comment by Dr. Krishna Kumari Challa on September 25, 2025 at 12:27pm

A new look at how the brain works reveals that wiring isn't everything

How a brain's anatomical structure relates to its function is one of the most important questions in neuroscience. It explores how physical components, such as neurons and their connections, give rise to complex behaviors and thoughts. A recent study of the brain of the tiny worm C. elegans provides a surprising answer: Structure alone doesn't explain how the brain works.

C. elegans is often used in neuroscience research because, unlike the incredibly complex human brain, which has billions of connections, the worm has a very simple nervous system with only 302 neurons. A complete, detailed map of every single one of its connections, or brain wiring diagram (connectome), was mapped several years ago, making it ideal for study.

In this research, scientists compared the worm's physical wiring in the brain to its signaling network, how the signals travel from one neuron to another. First, they used an electron microscope to get a detailed map of the physical connections between its nerve cells. Then, they activated individual neurons with light to create a signaling network and used a technique called calcium imaging to observe which other neurons responded to this stimulation.

Finally, they used computer programs to compare the physical wiring map and the signal flow map, identifying any differences and areas of overlap.

The team discovered that the brain's functional organization differs from its anatomical structure. An analogy is that the brain's structure is like a city map showing every street. However, the function is more akin to traffic flow, with jams, detours and shortcuts that are not visible on the map. In other words, brain activity does not always follow the predictable pathways of its physical wiring.

Sophie Dvali et al, Diverging Network Architecture of the C. elegans Connectome and Signaling Network, PRX Life (2025). DOI: 10.1103/6wgv-b9m6

Comment by Dr. Krishna Kumari Challa on September 25, 2025 at 12:02pm

AI-generated voices now indistinguishable from real human voices

Many people still think of AI-generated speech as sounding "fake" or unconvincing and easily told apart from human voices. But new research shows that AI voice technology has now reached a stage where it can create "voice clones" or deepfakes which sound just as realistic as human recordings.

The study compared real human voices with two different types of synthetic voices, generated using state-of-the-art AI voice synthesis tools. Some were "cloned" from voice recordings of real humans, intended to mimic them, and others were generated from a large voice model and did not have a specific human counterpart.

Participants were asked to evaluate which voices sounded most realistic, and which sounded most dominant or trustworthy. Researchers also looked at whether AI-generated voices had become "hyperreal," given that some studies have shown that AI-generated images of faces are now judged to be human more often than images of real human faces.

While the study did not find a "hyperrealism effect" from the AI voices, it did find that voice clones can sound as real as human voices, making it difficult for listeners to distinguish between them. Both types of AI-generated voices were evaluated as more dominant than human voices, and some were also perceived as more trustworthy.

Voice clones sound realistic but not (yet) hyperrealistic, PLOS One (2025). DOI: 10.1371/journal.pone/0332692

Comment by Dr. Krishna Kumari Challa on September 25, 2025 at 11:17am

Only then does the process lurch back into motion: The egg cell finally divides, and the chromosome pairs that were connected by crossovers are finally separated to deliver a single set of chromosomes to the mature egg. Maintaining the crossover connections over many years is a major challenge for immature egg cells.
If chromosome pairs aren't connected by at least one crossover, they can lose contact with each other, like two people separated in a jostling crowd. This causes them to segregate incorrectly when the cell finally divides, producing egg cells with extra or missing chromosomes. This can cause infertility, miscarriage or genetic conditions such as Down syndrome, in which a child is born with an extra copy of chromosome 21, leading to cognitive impairment, heart defects, hearing loss and other problems.
Researchers have identified dozens of proteins that bind and process these junctions. They used a technique called "real-time genetics" to investigate the function of those proteins.
With this method, they made cells degrade one or more specific proteins within the junction-associated structures. They could then analyze the DNA from these cells, to see whether the junctions were resolved and if they formed crossovers. In this way, they built up a picture in which a network of proteins function together to ensure that crossovers are formed.
They identified key proteins such as cohesin that prevent an enzyme called the STR complex (or Bloom complex in humans) from inappropriately dismantling the junctions before they can form crossovers.

They protect the double Holliday junction. That is a key discovery.
Failure to protect double-Holliday junctions may be linked to fertility problems in humans.

Shangming Tang et al, Protecting double Holliday junctions ensures crossing over during meiosis, Nature (2025). DOI: 10.1038/s41586-025-09555-1

Part 2

Comment by Dr. Krishna Kumari Challa on September 25, 2025 at 11:14am

Molecular discovery reveals how chromosomes are passed from one generation to the next

When a woman becomes pregnant, the outcome of that pregnancy depends on many things—including a crucial event that happened while she was still growing inside her own mother's womb. It depends on the quality of the egg cells that were already forming inside her fetal ovaries. The DNA-containing chromosomes in those cells must be cut, spliced and sorted perfectly. In males, the same process produces sperm in the testes but occurs only after puberty.

If that goes wrong, then you end up with the wrong number of chromosomes in the eggs or sperm. This can result in infertility, miscarriage or the birth of children with genetic diseases.

In a paper published Sept. 24 in the journal Nature,  researchers report a major new discovery about a process that helps safeguard against these mistakes. They have pieced together the choreography of proteins that connect matching chromosome pairs—ensuring that they are sorted correctly as egg and sperm cells develop and divide.

These discoveries required methods to watch the molecular events of chromosome recombination unfold with unprecedented detail. This involved genetic engineering in budding yeast—a model organism that has been used for decades to discover how fundamental cellular processes work.

Humans have 46 chromosomes in each of our cells, made up of 23 pairs of matching, "homologous" chromosomes, with one of each pair inherited from each parent. Early in the process of making sperm or eggs, those chromosome pairs line up, and the parental chromosomes break and rejoin to each other. These chromosome exchanges, called "crossovers," serve two important functions.

First, they help ensure that each chromosome that is passed on to the offspring contains a unique mixture of genes from both parents. Crossovers also keep the chromosomes connected in matching pairs. These connections guide the distribution of chromosomes when cells divide to produce eggs and sperm. Maintaining crossover connections is especially crucial in females.

As chromosomes pair up in developing egg or sperm cells, matching DNA strands are exchanged and twined together over a short distance to form a structure called a "double Holliday junction." DNA strands of this structure are then cut to join the chromosomes forming a crossover.

In males, developing immature sperm cells then immediately divide and distribute chromosomes to the sperm. In contrast, egg cells developing in the fetal ovary arrest their development after crossovers have formed. The immature egg cells can remain in suspended animation for decades after birth, until they are activated to undergo ovulation.

Part 1

Comment by Dr. Krishna Kumari Challa on September 25, 2025 at 9:24am

Study finds microplastics in all beverages tested, raising exposure estimates

Microplastics have found their way deep inside our bones, brains, and even babies. A UK study found that 100% of all 155 hot and cold beverage samples tested contained synthetic plastic particles.

MPs are tiny pieces of plastic ranging in size from 1 μm to 5 mm, which are widespread across aquatic, terrestrial, and even airborne environments. They have become a growing health concern for living beings across species due to their ability to accumulate and carry toxic chemicals through the food webs.

Humans come into contact with MPs every day through food, water, consumer goods, and even air.

The researchers tested different products from popular UK brands, including coffee, tea, juices, energy drinks, soft drinks, and even tap and bottled water, and not a single beverage was free of microplastics (MPs). Surprisingly, the more expensive tea bag brand showed a higher concentration of MPs, compared to the cheaper ones.

Traces of plastics, including polypropylene, polystyrene, polyethylene terephthalate, and polyethylene—commonly used for food packaging and disposable containers—were found in the fluids. The daily average exposure through beverages was found to be 1.65 MPs/kg body weight per day.

The findings are published in Science of the Total Environment.

This can be true to all countries in the world.

 Muneera Al-Mansoori et al, Synthetic microplastics in hot and cold beverages from the UK market: Comprehensive assessment of human exposure via total beverage intake, Science of The Total Environment (2025). DOI: 10.1016/j.scitotenv.2025.180188

Comment by Dr. Krishna Kumari Challa on September 25, 2025 at 9:17am

The Ganges River is drying at an unprecedented rate, new study finds

The Ganges River is in crisis. This lifeline for around 600 million people in India and neighboring countries is experiencing its worst drying period in 1,300 years. Using a combination of historical data, paleoclimate records and hydrological models, researchers discovered that human activity is the main cause. They also found that the current drying is more severe than any recorded drought in the river's history.

In their study, published in the Proceedings of the National Academy of Sciences, researchers first reconstructed the river's flow for the last 1,300 years (700 to 2012 C.E.) by analyzing tree rings from the Monsoon Asia Drought Atlas (MADA) dataset. Then they used powerful computer programs to combine this tree-ring data with modern records to create a timeline of the river's flow. To ensure its accuracy, they double-checked it against documented historical droughts and famines.

The scientists found that the recent drying of the Ganges River from 1991 to 2020 is 76% worse than the previous worst recorded drought, which occurred during the 16th century. Not only is the river drier overall, but droughts are now more frequent and last longer. The main reason, according to the researchers, is human activity. While some natural climate patterns are at play, the primary driver is the weakening of the summer monsoon.

This weakening is linked to human-driven factors such as the warming of the Indian Ocean and air pollution from anthropogenic aerosols. These are liquid droplets and fine solid particles that come from factories, vehicles and power plants, among other sources and can suppress rainfall. The scientists also found that most climate models failed to spot the severe drying trend.

How to avoid this?

The researchers suggest two main courses of action. Given the mismatch between climate models and what they actually found, they are calling for better modeling to account for the regional impacts of human activity.

And because the Ganges is a vital source of water for drinking, agricultural production, industrial use and wildlife, the team also recommends implementing new adaptive water management strategies to mitigate potential water scarcity.

Dipesh Singh Chuphal et al, Recent drying of the Ganga River is unprecedented in the last 1,300 years, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2424613122

Comment by Dr. Krishna Kumari Challa on September 24, 2025 at 9:52am

Scientists show how to grow more nutritious rice that uses less fertilizer

The cultivation of rice—the staple grain for more than 3.5 billion people around the world—comes with extremely high environmental, climate and economic costs.

This may be about to change, thanks to new research. 

Scientists have shown that nanoscale applications of the element selenium can decrease the amount of fertilizer necessary for rice cultivation while sustaining yields, boosting nutrition, enhancing the soil's microbial diversity and cutting greenhouse gas emissions. 

In a new paper published in the Proceedings of the National Academy of Sciences, they demonstrate for the first time that such nanoscale applications work in real-world conditions.

They used an aerial drone to lightly spray rice growing in a paddy with the suspension of nanoscale selenium. That direct contact means that the rice plant is far more efficient at absorbing the selenium than it would be if we applied it to the soil.

Selenium stimulates the plant's photosynthesis, which increased by more than 40%. Increased photosynthesis means the plant absorbs more CO₂, which it then turns into carbohydrates. Those carbohydrates flow down into the plant's roots, which causes them to grow.

Bigger, healthier roots release a host of organic compounds that cultivate beneficial microbes in the soil, and it's these microbes that then work symbiotically with the rice roots to pull more nitrogen and ammonium out of the soil and into the plant, increasing its NUE from 30 to 48.3%, decreasing the amount of nitrous oxide and ammonia release to the atmosphere by 18.8–45.6%.

With more nutrients coming in, the rice itself produces a higher yield, with a more nutritious grain: levels of protein, certain critical amino acids, and selenium also jumped.

On top of all of this, they  found that their nano-selenium applications allowed farmers to reduce their nitrogen applications by 30%. Since rice cultivation accounts for 15–20% of the global nitrogen use, this new technique holds real promise for helping to meet the triple threat of growing population, climate change, and the rising economic and environmental costs of agriculture.

Wang, Zhenyu et al, Nanotechnology-driven coordination of shoot–root systems enhances rice nitrogen use efficiency, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2508456122

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