Sunday, 10 May 2026

Chuck's picture corner to May 10, 2026

It's been a cool week, a story of disaster and success. 
Still below avg. temps forecast for the next two weeks.
 I managed to unblock the drain in the basement with consistent efforts. It ran with a small whirlpool till all the water was gone, no more pumping required. 
 Secondly I managed to convince the rat family that had moved into the house to move along. Being near the corn processing factory close to the St. Lawrence and generally all along the river, rats are populous in the landscape.  I used glue traps, they seem to work fairly well, even when a rat escapes it leaves a bunch of fur behind after a lot of struggling. Moma rat didn't make it out her trap, nor one of the young ones. Two rats did escape with a lot of effort, not a sign for the past 2 days. Traps go into the now drying basement. The critters ate a pile of my pepper plant seedlings, a last straw for me.

sunrise this morning

Cherry blossoms

Yippee the second year the grafted cherry tree outside the office window is flowering. No cherries last year but I'm hopeful for this year.

Lots of viola in the lawn this spring, three colours from white to dark blue.

The Sun is still riding high at supper time.

the forget me nots are starting to bloom, they will be around for weeks before fading back into the lawn.

one of my favorite spirea beginning to leaf out.

the tulips almost ready to open

an interesting spring fungi, growing near one of the front flower circles.

the forsythia still going strong with no hot weather to stop it.

The rhubarb is coming along.

This current bush is going like crazy.

spring bulbs, just keep coming back year after year.

one of the fancier daffodils is finally opening.

A chick-a-dee's home.

road trip to pick up steel sheeting, the new siding for the back of the house.

driving the St. Lawrence is enjoyable every time.

late spring geese on the fly

the rats and mice sure process the compost bin fast, I put fresh compost in at least every second day all year round

The pear tree begins.

Elderberry

a wet part of lawn grows more moss than grass.

This monk's hood seems to enjoy it's spot in the yard.


Enjoy the Day
https://chuckincardinal.blogspot.com/

Ravens Don’t Follow Wolves, They Predict Them

By Max Planck Inst. of Animal Behavior, May 9, 2026
https://scitechdaily.com/ravens-dont-follow-wolves-they-predict-them/

Two ravens soar above a wolf pack in Yellowstone. This type of short-distance following is common, but prolonged following is extremely rare. 
Credit: Daniel Stahler / YNP

When wolves bring down prey in Yellowstone National Park, ravens often appear almost immediately. Long before the predators finish feeding, the birds gather nearby to grab scraps of meat. Their ability to locate fresh kills so quickly has puzzled observers for years, leading many people to assume that ravens simply follow wolves across the landscape.

Ravens Use Memory To Find Wolf Kills

A new study suggests the real explanation is far more impressive. After tracking ravens and wolves in Yellowstone for more than two years, researchers discovered that ravens rely heavily on memory. Instead of shadowing wolf packs over long distances, the birds remember places where wolves frequently make kills and return to those areas later.

“They can fly six hours non-stop, straight to a kill site,” says Dr. Matthias Loretto, the study’s lead author.

The findings, published in Science, indicate that ravens use spatial memory and navigation skills to search for food spread across large areas. According to Loretto, ravens do not need to stay close to wolves all the time because they can recall where food is most likely to appear. “Ravens can cover large distances by flying, and they seem to have a good memory, so they don’t need to constantly follow wolves in order to profit from the predators,” he says.

The project was led by the Research Institute of Wildlife Ecology at the University of Veterinary Medicine Vienna and the Max Planck Institute of Animal Behavior (Germany), along with several international partners, including the Senckenberg Biodiversity and Climate Research Centre (Germany); School of Environmental and Forest Sciences at the University of Washington (USA); and Yellowstone National Park (USA).

The team fitted ravens with GPS backpacks, seen here with antenna protruding. 
Credit: Matthias Loretto

Tracking Ravens and Wolves in Yellowstone

Researchers carried out the study in Yellowstone National Park, where wolves were reintroduced in the mid-90s after being absent for 70 years. About one quarter of the park’s wolves wear tracking collars each year, allowing scientists to monitor their movements.

Dr. Dan Stahler, a Yellowstone biologist who has studied the wolves since their return, says ravens often seem closely connected to the predators. “You see them flying directly above traveling packs or hopping close behind wolves as they take down prey.”

Because wolves regularly leave behind edible remains, scientists long believed ravens followed a simple strategy: stay near wolves to find food. “We all assumed that the birds had a very simple rule; just stick close to the wolves,” says Stahler.

However, nobody had thoroughly tested that idea before. “We didn’t know what ravens were capable of because nobody had ever put them at the center; nobody had taken the scavenger’s point of view,” he says.

https://www.youtube.com/watch?v=Qx2l4STmpKk&t=2s

GPS Tracking Reveals Raven Intelligence

To better understand raven behavior, the team fitted 69 ravens with tiny GPS tracking devices. Loretto describes that number as unusually high for this kind of research. Capturing the birds was difficult because ravens are highly observant and cautious around unfamiliar objects.

“Ravens are so observant of the landscape that they don’t step into traps easily,” says Loretto.

Researchers carefully disguised traps to blend into the environment. Near campsites, they even used trash and fast food as camouflage and bait. Otherwise, “the ravens would suspect that something was off and wouldn’t come near it,” Loretto explains.

The scientists also analyzed movement data from 20 collared wolves. During winter, when ravens most often interact with wolves, GPS locations were recorded every 30 minutes for ravens and every hour for wolves. Researchers also tracked the locations and timing of wolf kills involving prey such as elk, bison, and deer.

Ravens Remember Productive Hunting Areas

Over two-and-a-half years of monitoring, scientists found only one clear case in which a raven followed a wolf for more than one kilometer or longer than one hour.

“At first, we were puzzled,” says Loretto. “Once we realized that ravens are not following wolves over long distances, we couldn’t explain why the birds still arrive so quickly at wolf kills.”

A deeper analysis eventually revealed the answer. Ravens repeatedly traveled back to areas where wolf kills commonly occurred rather than directly trailing predators. Some birds flew as far as 155 kilometers in a single day, often along remarkably direct routes toward places where carcasses were likely to appear, even though the exact timing of a kill could not be predicted.

Researchers found that wolf kills often clustered in certain parts of the landscape, especially flat valley bottoms where wolves hunt more successfully. Ravens visited these areas much more often than places where kills rarely happened. This suggests the birds learn and remember long-term feeding patterns across the environment.

“We already knew that ravens can remember stable food sources, like landfills,” says Loretto. “What surprised us is that they also seem to learn in which areas wolf kills are more common. A single kill is unpredictable, but over time some parts of the landscape are more productive than others — and ravens appear to use that pattern to their advantage.”

What the Study Reveals About Animal Intelligence

The researchers believe ravens may still follow wolves over short distances in some situations. Nearby cues, including wolf behavior or howling, could help birds locate kills once they are already in the area.

“To find wolf kills locally, ravens likely use short-range cues, like monitoring wolf behavior or listening to wolf howling,” says Loretto.

Still, the broader pattern points strongly toward memory-based navigation. Ravens appear to decide where to search using knowledge gained from previous experiences, sometimes traveling across tens or even hundreds of kilometers.

Senior author Prof John M. Marzluff of the University of Washington says the findings reveal remarkable flexibility in raven behavior. “What our study clearly shows is that ravens are flexible in where they decide to feed. They don’t stay tied to a particular wolf pack. With their sharp senses and memory of past feeding locations, they can choose among many foraging opportunities far and wide. This changes how we think about how scavengers find food—and suggests we may have underestimated some species for a long time.”



The Life of Earth
https://chuckincardinal.blogspot.com/

Scientists Discover Hidden Methane Source Beneath Every Major City

By V. Doon, City U. of Hong Kong, May 9, 2026

Methane is one of the most powerful drivers of global warming, yet scientists may have overlooked a major source hiding beneath cities worldwide. 
Credit: Stock

Scientists have discovered that urban sewers may be a surprisingly significant source of methane emissions.

Methane ranks behind carbon dioxide as the world’s second most important greenhouse gas. The Climate and Clean Air Coalition estimates that human-caused methane emissions are responsible for nearly 45% of current net warming, making methane a major driver of climate change.

Now, an international team led by a City University of Hong Kong (CityUHK) scholar has identified sewers as a previously underestimated methane source and created the first estimation tool designed for global use.

The researchers estimate that sewer systems release 1.18 to 1.95 million tons of methane worldwide each year. The finding suggests that wastewater management contributes more to greenhouse gas emissions and warming than previously recognized, and that sewer emissions should be included more accurately in climate accounting and reduction plans.

The 20-year research effort was led by Professor Yuan Zhiguo, Chair Professor of the School of Energy and Environment at CityUHK. The team included scholars from The University of Queensland, The Hong Kong Polytechnic University, Tianjin University, and Tongji University. Their study was recently published in Nature Water.


Led by Professor Yuan Zhiguo, Chair Professor of the School of Energy and Environment at CityUHK, the research lasted for 20 years. 
Credit: City University of Hong Kong



Sewers were wrongly overlooked

Urban sewers have often been treated as a negligible methane source because wastewater was thought to move through them too quickly for substantial methane formation, and because emissions from sewer networks are hard to measure and quantify. As a result, greenhouse gas inventories from the IPCC and many countries currently assume that methane emissions from urban sewers are zero.

Yet sewage contains large amounts of biodegradable organic matter, while oxygen-poor conditions are common inside sewer systems. Together, those factors can create an environment where methane can form.

A model built from pipes

Professor Yuan’s research team has long focused on new approaches for wastewater systems and environmental biotechnology. In 2008, the team developed the SeweX model, which simulates physical, chemical, and biological processes inside sewers, including the production of hydrogen sulfide and methane.

Because field data were limited for calibrating the methane prediction parts of SeweX, the team gathered measurements from sewer networks in Australia using a customized online sensor. Those data were used to calibrate and validate the model.

Using this innovative tool, the team estimates that global sewer systems emit approximately 1.18 to 1.95 million tons of methane annually. 
Credit: City University of Hong Kong

After calibrating SeweX, the researchers modeled nearly 3,000 pipeline scenarios with different structures and operating conditions. Their results showed that methane production in sewers is closely linked to the wetted surface of pipes. From that finding, they developed a simplified model that can estimate sewer methane emissions using information such as pipe size, slope, designed and actual average dry weather flows, and wastewater temperature.

The model was then tested against real-world data from 21 cities in Australia, the United States, China, and Belgium, leading to a comprehensive tool for estimating methane emissions from sewer systems.
Wastewater’s hidden climate cost

Using the new tool, the team estimated that sewer systems worldwide release about 1.18 to 1.95 million tons of methane each year. That would add 1.7% to 3.3% to current estimates of global methane emissions from the waste sector, and about 16% to 38% to the estimated overall carbon footprint of wastewater management.


Professor Yuan’s research team has been dedicated to developing innovative solutions for wastewater systems and environmental biotechnology.
 Credit: City University of Hong Kong



Professor Yuan remarked, “Our research confirms that sewers are not a zero-emission source; rather they represent a quantifiable source of methane emissions with significant global climate implications. As urban sewers continue to expand, their potential methane emissions will also increase. Therefore, including them in the greenhouse gas accounting system will help improve national greenhouse gas inventories and provide a new entry point for emissions reduction, further advancing the global goal of sustainable development.”



The Life of Earth
https://chuckincardinal.blogspot.com/

Saturday, 9 May 2026

One Critical Factor Predicts Longevity Better Than Diet or Exercise, Study Finds

09 May 2026, By D. Nield

(rattanakun/Canva)

Diet and exercise are both factors that can influence how long you live, but they're not the single greatest predictor of your longevity, research suggests.

According to a recent study, there's something else that might have more of an effect in terms of curtailing your lifespan.

While poor sleep has been previously linked to a host of health issues, this latest investigation found that getting enough shut-eye had a stronger connection to living longer than diet and exercise – factors that are known to add years to your life.

Researchers from Oregon Health & Science University (OHSU) crunched the numbers on survey data from across the US, covering the years 2019 to 2025.

Measures of life expectancy were compared against self-reported evaluations of sleep duration, with less than seven hours per night considered a threshold for insufficient sleep.

They then factored in other variables that can affect life expectancy, including physical inactivity, employment status, and educational level. The association between insufficient sleep and lower life expectancy still held. Only smoking had a stronger link.

"I didn't expect [insufficient sleep] to be so strongly correlated to life expectancy," said OHSU sleep physiologist Andrew McHill.

"We've always thought sleep is important, but this research really drives that point home: People really should strive to get seven to nine hours of sleep if at all possible."

Life expectancy's association with sleep is stronger than with many other factors, including diet and exercise. Although, as this graph shows, physical activity and social connections also influence life expectancy. 
(McAuliffe et al., Sleep Adv., 2025)

As a purely observational study, the research, published in 2025, can't prove that less sleep knocks months or years off your life.

A study like this also can't untangle the complex interactions between sleep, diet, and exercise. The results do suggest the amount of sleep you get each night is a significant indicator of long-term health.

Adequate sleep is vital for almost every aspect of our well-being: missing a single night of slumber can impact brain circuitry and the body's immune system, for example.

It's not unreasonable to suggest that such health issues may contribute to mortality in the long run. In particular, the researchers highlight obesity and diabetes as two conditions linked with poor sleep that could reduce life expectancy.

"It's intuitive and makes a lot of sense, but it was still striking to see it materialize so strongly in all of these models," said McHill.

"Getting a good night's sleep will improve how you feel but also how long you live."

The good news is that our sleep routines are, at least to some extent, modifiable within the limits of our caregiving and work commitments.

It might be worth quitting that habit of doomscrolling in bed, or squeezing in a session of yoga or tai chi now and then.

Both the American Academy of Sleep Medicine and the Sleep Research Society recommend banking at least seven hours of sleep a night, although there is some evidence that you might be able to catch up on the weekends if you need to.

"This research shows that we need to prioritize sleep at least as much as we do what we eat or how we exercise," said McHill.

"Getting a good night's sleep will improve how you feel but also how long you live."


The Life of Earth
https://chuckincardinal.blogspot.com/

What Are You Actually Swallowing When You Take Probiotics?

09 May 2026, ByB. Langdon, The Conversation

(Douglas Sacha/Moment/Getty Images)



Standing by the counter at the pharmacist waiting to pick up my prescription, I couldn't help noticing the prominent display of probiotics on the counter.

It was two years ago, and I was reading everything I could find on microbiomes and probiotics – whether in books, journals or in shops – in preparation for writing my book The Microbiome: What Everyone Needs to Know.

For days I had focused just on probiotics and here they were, temptingly in front of me, ready for me to buy.

The packaging was so glossy and it's claims so intriguing, I found myself picking up the box to see what they were saying.

"Supporting gut health." "Friendly bacteria."

I was about to get antibiotics for my tonsillitis. Should I get some probiotics? I'd heard they might help replace the "good" gut bacteria that antibiotics can wipe out.


The microbes in everybody's gut make up their individual microbiome.
 (Science Photo Library/Canva)



The pharmacist knew me by sight, partly because he had just looked down my throat and prescribed them for me and partly because I'm a local GP. He nodded encouragingly and pointed at the display.

"These are very popular," he said.

I turned the box over. The packaging did best when describing what it contained. Thirty capsules to be taken every day, each containing 5 billion live cultures.

I compared it with the others on the shelf. Some contained 2 billion, some 10 billion. One contained 25 billion bacteria per capsule. It was a huge number and a huge dosage range. Were these dosages safe?

It wasn't so clear on what live cultures were exactly, describing them variously as "trusted" or "friendly". Higher-dose brands described themselves as "diverse" or "powerful", sounding more like the boardroom of a Fortune 500 company than a dietary supplement.

When it came to what they did, things became vague. Apparently, probiotics are there to "complement your natural gut bacteria" or alternatively to "complement your everyday life".

It took a bit of time for the pharmacist to package up my medication and label it, so I carried on and read the small print.

Each brand was very confident in its ability to survive the stomach acid: they were also confident on the research. "Most researched live culture." "Highly researched strains." I had no difficulty in believing this, it was the lack of claims to efficacy that baffled me.

Finally, I found the actual ingredients. Each listed their various combinations of bacteria, some containing up to 15 different sorts, but always including several versions of lactobacilli and bifidobactera.

Lactobacillus acidophilus I knew as a bacteria needed to make yogurt. Bifidobacteria are also often used in the food industry. Both are typical residents of our guts, known to account for about 12% of our usual gut bacteria.

So why do probiotic products all seem to contain the same bacterial species? And why are their claims always so deliberately vague?

Almost one in 20 adults are taking probiotics: typically those of us with higher educational levels, higher incomes and better diets. If we just knew a bit more about microbes, would we still want to take them?

It is normal to consume a lot of bacteria on our food. Even with freshly washed or cooked food, on a typical day we consume 1.3 billion bacteria a day either on or in our food.

As soon as our food hits the stomach, our high levels of stomach acid kill or injure almost all the bacteria we consume. Only a few ever reach the colon and those few probiotic bacteria that survive usually only ever stay a few days.

But to swallow a probiotic capsule containing 25 billion, is 20 times the number of bacteria our body is used to handling: a huge microbial load. Even "friendly" probiotic bacteria can cause a serious infection if they get in the wrong place, such as the blood stream.

It's true that most people can manage this huge microbial load fine because of our innate gut defence systems. But probiotics should be avoided by those with weak immune systems, who may be less able to keep these bacteria contained and are at higher risk of them spreading and causing infection.

The reason that out of all the millions of bacteria available in the world, probiotic brands always home in on exactly the same microbes is because these are all bacteria that are known to be safe or used in the food industry since before 1958.

If a microbe is officially designated "Generally Recognized As Safe", then the producer need undertake no further research. And if the producer then sticks to general claims of efficacy – what's known as a "qualified health claim", they don't even have to prove it works.

https://www.youtube.com/watch?v=qg2A5B70OVE&t=1s

Generally Recognized as Safe explained.

But even with no efficacy claims at all, the probiotic industry still seems to get its message across – and, as I handled the box of probiotics, I still had a strong feeling that this product was good for me, would make me healthier, and that I should buy it.

I held the box uncertainly. "Do you want these as well?" the pharmacist asked.
I checked the price: £17.99 for 30 probiotic capsules (low dose) for something I already had inside me from eating ordinary food. I decided to stick to the antibiotic prescription only, for £9.90.

So, do probiotics work?

I have learned to equivocate when asked this, because people who ask me – usually enthusiastically and with a smile – are invested in the concept of probiotics and have often already been taking them.

To avoid upsetting people I now usually say: "Well, they probably haven't done you any harm."

Apart from the cost.

Berenice Langdon, Senior Lecturer and Honorary Consultant, St George's, University of London



The Life of Earth
https://chuckincardinal.blogspot.com/

This Popular Supplement May Boost Your Brain, Not Just Your Muscles

By Taylor & Francis Group, May 8, 2026

Creatine is best known for boosting athletic performance, but it also plays a key role in how the body produces energy. Research shows it can enhance strength and training capacity, and may even support brain function in certain groups. Scientists are now investigating its potential in areas like mental health and aging. 
Credit: Shutterstock

Creatine is often linked to gym performance, but its real impact goes much deeper.

Creatine is widely recognized as a supplement used by athletes and fitness enthusiasts to improve performance. But its effects extend beyond the gym. Scientists have been studying how this naturally occurring compound influences both physical and mental function, revealing a more complex picture than many people expect.

From supporting energy production to its possible role in future medical treatments, creatine continues to attract attention from researchers.

Dr. Mehdi Boroujerdi, a pharmaceutical researcher and former professor, conducted a detailed review of creatine in the Handbook of Creatine and Creatinine In Vivo Kinetics. His analysis helps clarify how creatine works and what current evidence suggests about its benefits.

How Creatine Works in the Body

Creatine is produced naturally in the liver, kidneys, and pancreas using amino acids such as glycine, arginine, and methionine.

After it is made, creatine enters the bloodstream and is delivered to tissues that require energy, especially muscle. About 95% of the body’s creatine is stored in skeletal muscle, while smaller amounts are found in the brain, heart, and other organs.

Within cells, creatine is converted into phosphocreatine (PCR), which plays a key role in restoring adenosine triphosphate (ATP), the body’s primary energy source.

This rapid recycling of ATP is essential for tissues that use large amounts of energy, including skeletal muscle, the heart, and the brain. It allows cells to continue functioning during periods of intense activity or stress, which explains why creatine has become so popular among athletes.

Once creatine has been used, it breaks down into creatinine. This waste product is filtered by the kidneys and eliminated through urine.

The body can only store a limited amount of creatine, and individual levels vary. As a result, responses to supplementation can differ from person to person.

Despite frequent claims online, creatine is not a steroid. “Creatine’s role in muscle development is solely to provide energy for contraction and respiration; it is certainly not a substitute for steroids,” Dr. Boroujerdi explains.

Creatine Supplement Benefits and Performance Effects

Creatine monohydrate is the most researched and commonly used supplement form.

Studies summarized in the book show that supplementation increases creatine and phosphocreatine levels in muscle. This supports faster ATP regeneration during short, intense bursts of activity, which can improve strength, sprint performance, and overall training capacity.

Creatine may also have effects beyond physical performance. Research suggests it could support cognitive function, including memory, mood, and processing speed, particularly in individuals with lower baseline creatine levels, such as older adults.

Scientists are also exploring whether creatine could play a role in managing conditions such as Parkinson’s disease, depression, and menopause related muscle and bone loss. While early findings are encouraging, more studies are needed before firm conclusions can be drawn.

“Creatine’s anti-inflammatory and antioxidant properties further underscore its promise in clinical settings, though more robust trials are needed to confirm these benefits,” he explains.

“With sufficient justification, appropriate dosage form, and dosing regimen, creatine may eventually be recognized as an over-the-counter therapeutic agent rather than merely a dietary supplement.”

Creatine Dosage and Absorption

A common supplementation strategy starts with a loading phase of 20 grams per day (split into four doses) for 5-7 days. This is typically followed by a maintenance dose of 3-5 grams per day.

“This approach rapidly saturates muscle creatine stores, but a lower daily dose of 3-5 grams can achieve similar saturation over a longer period (approximately 28 days),” Dr. Boroujerdi says.

Not all creatine that is consumed is absorbed by the body. Absorption depends on factors such as digestive stability and the capacity of muscle tissue to store creatine. Taking creatine with carbohydrates may improve uptake by increasing insulin-mediated transport.

Factors That Influence Creatine’s Effects

Research indicates that the effects of creatine can vary based on sex, age, and diet.

Men and women may respond differently due to differences in muscle mass and starting creatine levels. Women often have lower baseline levels, which may lead to greater relative improvements with supplementation.

Older adults may benefit from creatine’s potential to help preserve muscle mass, bone density, and cognitive function.

Vegetarians and vegans, who typically consume little creatine through their diets, often have lower baseline levels and may experience stronger responses to supplementation. However, dietary patterns vary, so individual results differ.

“There is a pressing need for well-designed research projects in humans, utilizing labeled creatine to generate relevant data and illuminate the grey areas of our knowledge about these compounds,” Dr. Boroujerdi explains.

Creatine is sometimes combined with other supplements, such as the amino acid beta-alanine, to enhance its effects. However, the effectiveness of these combinations varies, and more research is needed to determine optimal approaches.

Safety, Limitations, and What to Expect

Creatine is one of the most extensively studied dietary supplements and is considered safe for healthy individuals. Its potential uses continue to expand, but it is not without limitations.

“Despite its many benefits, creatine is not a magic bullet. It does not directly build muscle or replace the need for proper training and nutrition. Additionally, the belief that larger doses yield greater benefits is unfounded, as muscle creatine stores have a saturation limit. Excess creatine is simply excreted as creatinine, offering no additional advantage,” Dr. Boroujerdi says.

Concerns about side effects such as kidney damage have largely been dismissed in healthy individuals. However, people with existing kidney conditions should consult a healthcare provider before using creatine.

The benefits of creatine are not the same for everyone. Outcomes depend on baseline levels, dosage strategies and individual physiology.

“For now, creatine is best viewed as a supplement with significant potential, but not a panacea,” Dr. Boroujerdi says. “Whether you’re an athlete, a student, or simply someone looking to support your health, understanding the science behind creatine is key to making informed decisions.”



The Life of Earth
https://chuckincardinal.blogspot.com/

Friday, 8 May 2026

The Y Chromosome May Be Vanishing. What Does It Mean For The Future of Men?

08 May 2026, By C. Cassella


(Dmitry Bayer/Getty Images)



In 2002, evolutionary biologist Jenny Graves shared a controversial calculation.

The human Y chromosome, she wrote two years later in a commentary, "is running out of time."

The male-determining sex chromosome has lost 97 percent of its ancestral genes in the last 300 million years.

If that rate continues, Graves calculated, it could vanish in several million more.

The doomed fate of the Y chromosome quickly took the media by storm, in many cases without the nuance Graves had intended.

Her evolutionary musings were not supposed to predict the 'end of males', or the termination of the human species; they were a 'back-of-the-envelope' calculation in an academic paper that nevertheless produced a "hysterical reaction".

"It really amazes me that anyone is concerned that men will become extinct in 5 or 6 million years," Graves told ScienceAlert in 2025.

"After all, we have only been human for 0.1 million years. I think we'll be lucky to make it through the next century!"


Typical genetic inheritance in humans. 
(ttsz/Getty Images)



But if Graves' calculation is correct, what does that mean for the Y chromosome – and what does it mean for the future of men?

The good news is that similar chromosomes in other mammals, as well as fish and amphibians, have lost their sex-determining status in genetic shuffles, with species continuing to tell the tale.

In some rodents, for instance, the Y chromosome has been completely and silently replaced.

Three species of Y-less mole vole, for instance, Ellobius talpinus, Ellobius tancrei, and Ellobius alaicus, now have only X chromosomes. Sex-determining genes on their Y chromosomes were shifted elsewhere.

Spiny rats (Tokudaia osimensis), meanwhile, lost their Y chromosome to a new version, which now acts as a sex-determiner in its stead.

"If a new variant … should arise that works better than our poor old Y, it could take over very rapidly," predicted Graves.

"Maybe it already has in some human population somewhere – how would we know?"

After all, sex-determining variants aren't routinely screened for in genome studies, and if the Y chromosome's role transferred to another chromosome in a population, there'd be no obvious differences.

There would still be males, and they'd still be able to reproduce.

The fate of the Y chromosome has captured the world's attention for years now, and yet beneath the surface of sensationalized headlines, many don't realize a potent scientific debate is brewing, throwing two incompatible views of evolution into direct conflict.

One school of thought, which Graves subscribes to, frames the sex chromosome as a crumbling old-timer that is doomed to vanish and could be replaced at any moment.

The other school positions the Y chromosome as a tenacious survivor, at last safe and stable.

Evolutionary biologist Jenn Hughes from MIT's Whitehead Institute agrees with this latter interpretation.

For over a decade now, Hughes and Graves have respectfully disagreed over how to interpret the same evidence, partaking in open academic argument.

In 2012, Hughes and her colleagues found that very few core Y genes have been lost in the human lineage over the past roughly 25 million years.

More recent evidence has strengthened that argument, suggesting there is deep conservation of core Y genes in primates – compared to fish and amphibians, which display gradual deterioration of their Y chromosomes – and some scientists, such as Hughes, interpret this as long-term evolutionary stability of the Y chromosome in primates.

"Our work comparing Y gene content across many mammals showed that the gene loss was rapid at first, but quickly leveled off, and gene loss has essentially stopped," Hughes told ScienceAlert in 2025.

"The genes that are retained on the Y serve crucial functions across the whole body, so the selective pressure to maintain those genes is too great for them to be lost."

Graves disagrees with these interpretations. Just because a gene is deeply conserved does not mean it can't be replaced, she argues.

Plus, the additional genes found in the human Y sequence in recent years are largely repeat copies, she says, some of which could be inactive.


How a Y chromosome repairs itself without a second copy, as there are with two X chromosomes.
 (Silber, Middle East Fertility Society Journal, 2011)



In the past, Graves has called the Y chromosome the "DNA junkyard". Creating lots of copies of a gene can boost the odds that at least one survives, Graves explains, but it can also create evolutionary 'duds' by accident.

It's sort of like a game of telephone. The more a message is shared, the more likely it is to last, but it is also more likely to become distorted.

So why is the Y chromosome like this?

Evolution is to blame.

"In the ancestor of placental mammals, the X and Y chromosomes were identical and had about 800 genes," Hughes told ScienceAlert.


"Once the Y became specialized for male sex determination (about 200 million years ago), the X and Y stopped recombining in males, and the Y started losing genes. Meanwhile, the X could still recombine in XX females, so it remained largely unchanged."

Today, the human Y chromosome has only 3 percent of the genes it once shared with X. But these genes weren't lost at a constant rate. That's the biggest misconception, argues Hughes.

Graves agrees.

Her projected extinction date of 6 million years or so is based on a straight, unflappable deterioration of the Y chromosome, but she says that is highly unlikely, which means the estimate has a wide range of error.

"Anything from now to never," Graves told ScienceAlert. "I was surprised it was taken so seriously!"

While at certain moments it may look like the Y chromosome is stabilizing, Graves argues that these snapshots won't last, even if they have seemingly persisted for 25 million years.

"I don't see any reason to suppose that Y degradation has, or could halt in primates, or any other mammal group," Graves said.

"It's slow and proceeds in fits and starts, for reasons we well understand."

After a public debate between Hughes and Graves in 2011 on whether the Y chromosome is stable or doomed, the audience at the 18th International Chromosome Conference voted 50/50.

They were split right down the middle on which hypothesis was correct.

Let's hope it doesn't take 6 million years for a tie-breaker.



The Life of Earth
https://chuckincardinal.blogspot.com/

Is The Brain Born 'Blank' or 'Full'? New Study Reveals a Surprise

08 May 2026, By M. Irving

A collage of neurons in the mouse hippocampus, stained with tracer dyes. 
(© Jose Guzman/Jonas group)

A strange mouse study suggests that the brain isn't a 'blank slate' at birth, waiting for memories to be written onto it.

Instead, it appears to start life 'full' and messy, optimizing itself as it learns.

Neuroscientists at the Institute of Science and Technology Austria (ISTA) examined mouse brains from birth to adulthood, focusing on the complexity of a key memory circuit in the hippocampus.

This region of the brain is involved in spatial memory and in consolidating short-term memories into long-term ones.

The team found that in the youngest mouse brains, this network of CA3 pyramidal neurons was very dense, with seemingly random connections. As they get older, however, they become more refined and organized.

"This discovery was quite surprising," says Peter Jonas, neuroscientist at ISTA.


Left: A young mouse hippocampus is packed with a dense network of neurons.
 Right: This network is pruned as the mouse matures. 
(© Jake Watson/ISTA)



"Intuitively, one might expect that a network grows and becomes denser over time," Jonas explains.

"Here, we see the opposite. It follows what we call a pruning model: It starts out full, and then it becomes streamlined and optimized."

It's unclear exactly why the brain develops this way, but the researchers believe that neurons might connect more efficiently if the groundwork is already laid.

In a blank slate scenario, however, distant neurons would first have to find each other before they could communicate. That would take longer for a growing brain to learn.

Think of it this way: If you had to navigate from one spot to another, that would be much faster if you already had a dense network of roads, and all you had to do was pick which ones to take to get from A to B.

If, on the other hand, you had to build your own road from scratch to reach your destination, it's probably going to take a lot longer.

The team measured electrical activity and other cellular processes at three developmental stages in mice: just after birth, at around 7 or 8 days of age; in adolescence, between days 18 and 25; and in adulthood, around 45 to 50 days of age.

This revealed that neurons in this mouse hippocampal circuit start off dense and random but refine themselves into a more structured network over time.


Neurons filled with biocytin – a tracer that labels them during recording – are fixed and stained to allow full reconstruction of their shapes. 
(© Jose Guzman/Jonas group)



The researchers suggest that this may be because the hippocampus has a tough job of processing and linking information from your eyes, ears, and nose.

"That's a complex task for neurons," says Jonas.

"An initially exuberant connectivity, followed by selective pruning, might be exactly what enables this integration."

Whether or not these findings apply to human brains remains to be seen.

But either way, it's intriguing to think that your brain may be a work of art chiseled out of marble, rather than sculpted out of clay.



The Life of Earth
https://chuckincardinal.blogspot.com/

Scientists Have Created The First Ever 'Smell Map', And It's Stunning

07 May 2026, By J. Cockerill

The first detailed map of smell receptors in the nose of a mouse. 
(Datta Lab/Harvard)

Smell is a powerful sense. It signals to your body whether something will taste good (or terrible), that you are finally home, that it's about to rain, or spring has arrived, or the dog needs a bath.

But of all the senses, smell may be the least understood.

Now, scientists have brought us closer to understanding this mysterious sense by creating a detailed map that shows the arrangement of the thousands of different types of smell receptors embedded in the noses of mice.

The result is absolutely hypnotic.

A microscope photo of a cross-section of a mouse nose. The mouse was genetically modified to express green fluorescent protein in smell neurons. A small subset of dying neurons is labeled in red. 
(Datta Lab/Harvard)

"Olfaction is super-mysterious," says neurobiologist Sandeep Datta, senior author on the study. "It's the sense that has been missing a map for the longest time."

The map is based on data from more than 300 mice.

In the nose of a mouse, there are around 20 million olfactory neurons that each express one of thousands of kinds of cell receptors. Each of those neurons carries scent information from the nose to the brain.

Datta and team sequenced the genes of around 5 million individual nasal tissue cells, giving them a dataset of around 2.3 million olfactory sensory neurons to work with.

Then, they mapped out where active genes related to scent receptors were located.

The olfactory map revealed a highly organized arrangement of receptors in the nose. 
(Brann et al., Cell, 2026)

"Our results bring order to a system that was previously thought to lack order, which changes conceptually how we think this works," Datta says.

Previously, scientists had trouble detecting the receptors, and they assumed their arrangement must be random: any olfactory sensory neuron could express any one of the 1,100 possible olfactory receptors.

The new map, however, reveals that the kind of receptors these neurons express is very much based on the specific order in which they are arranged.

Because of this, they form a gradient of receptors in narrow horizontal bands that span from the top to the bottom of the nose.

As Datta and team write in their paper, spatial order in the olfactory system "arises from a continuously varying transcriptional code that precisely organizes the many discrete channels responsible for smell."

Further experiments revealed that this layout is modulated by naturally occurring retinoic acid, a molecule that can adjust gene expression within cells.

By using drugs to adjust the levels of retinoic acid in the mice, the team was able to shift the gradient of smell receptors in the nose.

They also found the arrangement of receptors in the nose aligns with how the brain's olfactory bulb is organized.

The team hopes that by getting a better grasp on the anatomy of smell in mice, they may better understand what's going on in the human nose, too.

Of course, there are many differences between the noses of mice and humans, but as mammals, we do tend to share some physical and genetic similarities.

Knowing how smell actually works could also one day help us understand how to restore it in people who have lost this world-enriching sense.

"Smell has a really profound and pervasive effect on human health, so restoring it is not just for pleasure and safety but also for psychological well-being," Datta says.

"We cannot fix smell without understanding how it works on a basic level."



The Life of Earth
https://chuckincardinal.blogspot.com/