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Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 11:45am

Human presence at waterholes may change animal behavior

When tourists venture into nature, their thoughts are often focused on the animals they'll get to see. But animals may also have them in mind, according to a new study from the University of Georgia published in the Journal of Zoology.

With how common tourism is becoming, humans and animals will cross paths more often. Not only are tourists coming to watch the animals, but researchers will also stay out for long periods of time to count populations of different species.

As such, the study focused on how humans being nearby influenced the behavior of African mammals, including lions and zebras, while at waterholes.

When humans are present, some animals shift their daily activity patterns. the carnivores changed because of the human presence, and the herbivores changed because of the carnivore presence. It was not just one species that altered their behavior.

The study used a series of camera traps that took photos once animals walked by. Based on these pictures, researchers determined when and how often animals were visiting waterholes.

When humans were around, the time of day when some mammals came to the waterhole would shift compared to periods when humans weren't present. Some would visit earlier, while others visited later.

Animals shifting schedules can lead to different species interacting when they usually wouldn't—something that's especially a problem for some herbivores that could run into predators who typically aren't active during those times of the day.

Because of how important tourism is for conservation and income, the researchers emphasized the need to consider how human activity can impact animals on a larger scale.

Part 1 

Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 11:41am

This work focuses on the study of the genome of the Oikopleura dioica species, a swimming organism of the marine zooplankton that belongs to the tunicates—a sister group of vertebrates—and is phylogenetically linked to evolutionary history. In this study model—a free-living tunicate or appendicularian—the team reconstructed the evolutionary history of fibroblast growth factor (FGF) gene families, which are critical in the developmental process of organisms.

"The findings suggest that the process of gene loss reduced the number of FGF growth factor gene families from eight to just two, which are the Fgf9/16/20 and Fgf11/12/13/14 families. These surviving subfamilies have doubled over the course of evolution to generate a total of 10 genes in appendicularians.
The "less, but more" evolutionary model "helps us to understand how sometimes losing opens up new possibilities for subsequent gains and, therefore, losses are necessary to favor the evolutionary origin of new adaptations

Gaspar Sánchez-Serna et al, Less, but More: New Insights From Appendicularians on Chordate Fgf Evolution and the Divergence of Tunicate Lifestyles, Molecular Biology and Evolution (2024). DOI: 10.1093/molbev/msae260

**

Part 2

Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 11:39am

Less, but more: A new evolutionary scenario marked by massive gene loss and expansion

Evolution is traditionally associated with a process of increasing complexity and gaining new genes. However, the explosion of the genomic era shows that gene loss and simplification is a much more frequent process in the evolution of species than previously thought, and may favor new biological adaptations that facilitate the survival of living organisms.

This evolutionary driver, which seems counter-intuitive—"less is more" in genetic terms—now reveals a surprising dimension that responds to the new evolutionary concept of "less, but more," i.e., the phenomenon of massive gene losses followed by large expansions through gene duplications.

This is one of the main conclusions of an article published in the journal Molecular Biology and Evolution.

The paper identifies new evolutionary patterns, and it outlines a new scenario, marked by the enormous potential for genetic change and evolutionary adaptation driven by large-scale gene loss and duplication in living organisms.

Gene loss is a widespread mechanism throughout the biological scale and represents an evolutionary driving force that can generate genetic variability and also biological adaptations, and this has traditionally been known as the 'less is more' hypothesis.

Now, the paper describes a new evolutionary framework called "less, but more," which extends the previous model in terms of the importance of gene loss as an evolutionary driving force.

Part 1

Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 11:33am

Students discover a new protein while investigating Streptococcus infection

Strep throat, something we've all had at some point in our lives, is caused by the bacteria Streptococcus pyogenes. Infection by Streptococcus can be fatal in serious cases and is the leading cause of death among flesh-eating diseases, resulting in over half a million deaths annually.

That scratchy, sore feeling at the back of your throat is a result of Streptococcus pyogenes infected by viruses called bacteriophages. These "phages" carry the genes for toxins that are responsible for strep throat, and when they invade Streptococcus pyogenes, they transfer these genes, enhancing the bacterium's ability to cause infection.

However, many people carry Streptococcus pyogenes on their bodies, and it doesn't make them sick. Some of the big questions in the field are when, how and why does it make you sick? And why does Streptococcus become a pathogen?

Two graduate students have discovered that phages use paratox to control the metabolism of Streptococcus, redirecting DNA processing pathways for the benefit of the phage.

With help from undergraduate student Julia Horne, the team was able to demonstrate that paratox also likely regulates when it is time for the phage to leave Streptococcus and go on to infect new bacteria. Muna and Horne now have a protein named after them, JM3 which stands for Julia Muna construct 3.

 This discovery, published in Nucleic Acids Research, has opened many doors for future research projects.

Tasneem Hassan Muna et al, The phage protein paratox is a multifunctional metabolic regulator of Streptococcus, Nucleic Acids Research (2024). DOI: 10.1093/nar/gkae1200

Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 11:24am

However, glycosylation has traditionally been notoriously difficult to study. Only a small portion of proteins in the cell are glycosylated and concentrating enough of them in a sample for studying (a process called 'enriching') tends to be laborious, expensive, and time-consuming.
So far, it's not been possible to do such studies on a systematic scale, in a quantitative fashion, and with high reproducibility. These are the challenges the researchers managed to overcome with the new method.
DQGlyco uses easily available and low-cost laboratory materials, such as functionalized silica beads, to selectively enrich glycosylated proteins from biological samples, which can then be precisely identified and measured. Applying the method to brain tissue samples from mice, the researchers could identify over 150,000 glycosylated forms of proteins ('proteoforms'), an increase of over 25-fold compared to previous studies.

The quantitative nature of the new method means that researchers can compare and measure differences between samples from different tissues, cell lines, species etc. This also allows them to study the pattern of 'microheterogeneity'—the phenomenon where the same part of a protein can be modified by many (sometimes hundreds of) different sugar groups.

One of the most common examples of microheterogeneity is human blood groups, where the presence of different sugar groups on proteins in red blood cells determines blood type (A, B, O, and AB). This plays a major role in deciding the success of blood transfusions from one individual to the other.

The new method allowed the team to identify such microheterogeneity across hundreds of protein sites.
With this new weapon, teh researchers tackled the present problem.
The team found that when compared to "germ-free mice," i.e. mice grown in a sterile environment such that they completely lack any microbes in and on their body, mice colonized with different gut bacteria had different glycosylation patterns in the brain. The changed patterns were particularly apparent in proteins known to be important in neural functions, such as cognitive processing and axon growth.

The study's datasets are openly available via a new dedicated app for other researchers.

Clément M. Potel et al, Uncovering protein glycosylation dynamics and heterogeneity using deep quantitative glycoprofiling (DQGlyco), Nature Structural & Molecular Biology (2025). DOI: 10.1038/s41594-025-01485-w

Part 2

Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 11:20am

Gut bacteria can alter brain proteins: New glycosylation method uncovers link

Our guts are home to trillions of bacteria, and research over the last few decades has established how essential they are to our physiology—in health and disease. A new study by researchers shows that gut bacteria can bring about profound molecular changes in one of our most critical organs—the brain.

The new study, published in the journal Nature Structural & Molecular Biology, is the first to show that bacteria living in the gut can influence how proteins in the brain are modified by carbohydrates—a process called glycosylation. The study was made possible by a new method the scientists developed—DQGlyco—which allows them to study glycosylation at a much higher scale and resolution than previous studies.

Proteins are the workhorses of our cells and their main building blocks. Sugars, or carbohydrates, on the other hand, are among the body's main sources of energy. However, the cell also uses sugars to chemically modify proteins, altering their functions. This is called glycosylation.

Glycosylation can affect how cells attach to each other (adhesion), how they move (motility), and even how they talk to one another (communication).

It is involved in the pathogenesis of several diseases, including cancer and neuronal disorders.

Part 1

Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 11:09am

Helping Evolution: How humans unintentionally altered the skulls of pigs

Short snouts and a flat profile—within a span of 100 years, humans have significantly changed the shape of the skulls of German domestic pigs. According to a team of scientists , this is likely down to new breeding practices introduced at the beginning of the 20th century.

The researchers analyzed 3D scans of 135 skulls of wild boars and domestic pigs from the early 20th and 21st centuries. Surprisingly, the same effects can even be observed in species that were kept separately. Their findings have been published in the journal Royal Society Open Science.

Humans have been keeping pigs as livestock for several centuries. During this time, the animals have changed considerably. For example, they have become larger and have lost their black and brown bristles and darker skin tone.

The demand for pork in some countries increased significantly at the beginning of the 20th century and breeders were encouraged to optimize their animals. They needed them to grow quickly, provide good meat, and be fertile.

For the current study, researchers analyzed 135 skulls from three different breeds: Deutsches Edelschwein, Deutsches Landschwein—and wild boars, who acted as a control group. The skulls were either from the early 20th century or were only a few years old.

The two domestic pig breeds exhibited significant changes: The animals' snouts became significantly shorter and flatter, while the skulls of the more contemporary animals no longer had a slightly outwardly curved forehead. Researchers  didn't expect such pronounced differences to appear within a span of only 100 years.

Remarkably, both breeds of domestic pig underwent the same changes, despite being kept separately. "These changes occurred even though breeders did not select the animals specifically for their skull shape, as this trait was not important for breeding. Instead, the changes appear to be an unintended by-product of selecting the desired traits.

Another reason for the alterations could be related to changes in the animals' diet. Nutrition is known to influence the growth and development of animals. Today, pigs are mainly fed pellets that are high in protein. In contrast, the skulls of wild boars, who remain omnivores, have not undergone such changes.

The findings demonstrate how strongly humans can influence the evolution of animals.

Charles Darwin assumed that long periods of time—millions of years—are required for major changes to take place. This work is further proof that humans can greatly accelerate this process through selective breeding, say the researchers.

Creationists are you listening?

A. Haruda et al, Evolution under intensive industrial breeding: skull size and shape comparison between historic and modern pig lineages, Royal Society Open Science (2025). DOI: 10.1098/rsos.241039

Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 10:01am

Almost all nations miss UN deadline for new climate targets

Nearly all nations missed a UN deadline Monday to submit new targets for slashing carbon emissions, including major economies under pressure to show leadership following the US retreat on climate change.

Just 10 of nearly 200 countries required under the Paris Agreement to deliver fresh climate plans by February 10 did so on time, according to a UN database tracking the submissions.

Under the climate accord, each country is supposed to provide a steeper headline figure for cutting heat-trapping emissions by 2035, and a detailed blueprint for how to achieve this.

Global emissions have been rising but need to almost halve by the end of the decade to limit global warming to safer levels agreed under the Paris deal.

This latest round of national pledges are the most important policy documents of this century.

Yet just a handful of major polluters handed in upgraded targets on time, with China, India and the European Union the biggest names on a lengthy absentee list.

Most G20 economies were missing in action with the United States, Britain and Brazil—which is hosting this year's UN climate summit—the only exceptions.

There is no penalty for submitting late targets, formally titled nationally determined contributions (NDCs).

They are not legally binding but act as an accountability measure to ensure countries are taking climate change seriously and doing their fair share toward achieving the Paris goals.

The sluggish response will not ease fears of a possible backslide on climate action as leaders juggle Trump's return and other competing priorities from budget and security crises to electoral pressure.

Source: News Agencies

Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 9:43am

Potassium-enriched salt shows promise for cutting recurrent stroke risk in clinical trial

Potassium supplements in salt were associated with reduced rates of recurrent stroke and mortality in a large-scale cluster randomized clinical trial involving patients.

Findings come from a subgroup (stroke patients) analysis within the original Salt Substitute and Stroke Study (SSaSS), an international study conducted by researchers.

Stroke ranks among the top causes of death and disability in low- and middle income countries, and recurrent events remain a major concern. High sodium intake and low potassium intake are considered key risk factors.

The SSaSS trial involved 600 villages and 20,995 individuals in rural China. In the previous studies, researchers replaced participants' salt with a 75% salt, 25% potassium chloride substitute.

In the study, "Salt Substitution and Recurrent Stroke and Death: A Randomized Clinical Trial," published in JAMA Cardiology, the team analyzed data from 15,249 participants who had previously reported suffering from stroke.

Researchers used data from the original study, which monitored blood pressure, stroke recurrence, mortality, and safety outcomes, including hyperkalemia risk. Urinary sodium/potassium excretion was also tracked.

Over the study period, recurrent stroke was 14% lower in the 25% potassium substitute group compared with the regular salt group, the same as found in the original full cohort study.

Mean systolic blood pressure over follow-up was lower in the salt substitute group compared with controls. A total of 2,735 recurrent stroke events occurred, with 691 fatal and 2,044 nonfatal episodes.

Hemorrhagic stroke showed a 30% relative reduction, and stroke-related deaths decreased by 21%. No meaningful difference in hyperkalemia was observed between groups.

Findings indicate that salt reduction with 25% potassium is a safe, low-cost dietary intervention that can reduce stroke recurrence and mortality among stroke survivors. Researchers suggest broader implementation of salt substitutes, particularly in regions with high sodium intake and limited access to preventive health care.

Xiong Ding et al, Salt Substitution and Recurrent Stroke and Death, JAMA Cardiology (2025). DOI: 10.1001/jamacardio.2024.5417

Comment by Dr. Krishna Kumari Challa on February 11, 2025 at 9:21am

Earth's inner core is less solid than previously thought

The surface of the Earth's inner core may be changing, as shown by a new study by  scientists that detected structural changes near the planet's center, published in Nature Geoscience.

The changes of the inner core have long been a topic of debate for scientists. However, most research has been focused on assessing rotation.

Located 3,000 miles below the Earth's surface, the inner core is anchored by gravity within the molten liquid outer core. Until now, the inner core was widely thought of as a solid sphere.

But a study conducted recently showed a different picture.

The study utilized seismic waveform data—including 121 repeating earthquakes from 42 locations near Antarctica's South Sandwich Islands that occurred between 1991 and 2024—to give a glimpse of what takes place in the inner core.

As the researchers analyzed the waveforms from receiver-array stations located near Fairbanks, Alaska, and Yellowknife, Canada, one dataset of seismic waves from the latter station included uncharacteristic properties the team had never seen before.

 The new study indicates that the near surface of the inner core may undergo viscous deformation, changing its shape and shifting at the inner core's shallow boundary.

The clearest cause of the structural change is interaction between the inner and outer core. The molten outer core is widely known to be turbulent, but its turbulence had not been observed to disrupt its neighbour the inner core on a human timescale.

The discovery opens a door to reveal previously hidden dynamics deep within Earth's core, and may lead to better understanding of Earth's thermal and magnetic field.

John Vidale, Annual-scale variability in both the rotation rate and near surface of Earth's inner core, Nature Geoscience (2025). DOI: 10.1038/s41561-025-01642-2. www.nature.com/articles/s41561-025-01642-2

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