Scientists have identified five ages of the human brain.
“Neuroscientists at the University of Cambridge have identified five “major epochs” of brain structure over the course of a human life, as our brains rewire to support different ways of thinking while we grow, mature, and ultimately decline.”
So wrote Fred Lewsey. Fred is the Communications Manager (Research) and is Responsible for: School of the Humanities and Social Sciences. (And I took this from this site.) He went on to report that: Four major turning points around ages nine, 32, 66 and 83 create five broad eras of neural wiring over the average human lifespan.
Being in my early 80’s I was most interested in that last turning point. This is the information about that era:
The last turning point comes around age 83, and the final brain structure epoch is entered. While data is limited for this era, the defining feature is a shift from global to local, as whole brain connectivity declines even further, with increased reliance on certain regions.
“Looking back, many of us feel our lives have been characterised by different phases. It turns out that brains also go through these eras,” added senior author Prof Duncan Astle, Professor of Neuroinformatics at Cambridge.
“Many neurodevelopmental, mental health and neurological conditions are linked to the way the brain is wired. Indeed, differences in brain wiring predict difficulties with attention, language, memory, and a whole host of different behaviours”
“Understanding that the brain’s structural journey is not a question of steady progression, but rather one of a few major turning points, will help us identify when and how its wiring is vulnerable to disruption.”
On November 24th this year, The Conversation published an article that spoke of the ancient closeness, as in genetically, of wolves and dogs.
I share it with you. It is a fascinating read.
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Thousands of genomes reveal the wild wolf genes in most dogs’ DNA.
Modern wolves and dogs both descend from an ancient wolf population that lived alongside woolly mammoths and cave bears. Iza Lyson/500px Prime via Getty Images
Dogs were the first of any species that people domesticated, and they have been a constant part of human life for millennia. Domesticated species are the plants and animals that have evolved to live alongside humans, providing nearly all of our food and numerous other benefits. Dogs provide protection, hunting assistance, companionship, transportation and even wool for weaving blankets.
Dogs evolved from gray wolves, but scientists debate exactly where, when and how many times dogs were domesticated. Ancient DNA evidence suggests that domestication happened twice, in eastern and western Eurasia, before the groups eventually mixed. That blended population was the ancestor of all dogs living today.
Molecular clock analysis of the DNA from hundreds of modern and ancient dogs suggests they were domesticated between around 20,000 and 22,000 years ago, when large ice sheets covered much of Eurasia and North America. The first dog identified in the archaeological record is a 14,000-year-old pup found in Bonn-Oberkassel, Germany, but it can be difficult to tell based on bones whether an animal was an early domestic dog or a wild wolf.
Dogs are not exactly descended from modern wolves. Rather, dogs and wolves living today both derive from a shared ancient wolf population that lived alongside woolly mammoths and cave bears.
In most domesticated species, there are often clear, documented patterns of gene flow between the animals that live alongside humans and their wild counterparts. Where wild and domesticated animals’ habitats overlap, they can breed with each other to produce hybrid offspring. In these cases, the genes from wild animals are folded into the genetic variation of the domesticated population.
For example, pigs were domesticated in the Near East over 10,000 years ago. But when early farmers brought them to Europe, they hybridized so frequently with local wild boar that almost all of their Near Eastern DNA was replaced. Similar patterns can be seen in the endangered wild Anatolian and Cypriot mouflon that researchers have found to have high proportions of domestic sheep DNA in their genomes. It’s more common than not to find evidence of wild and domesticated animals interbreeding through time and sharing genetic material.
That wolves and dogs wouldn’t show that typical pattern is surprising, since they live in overlapping ranges and can freely interbreed.
Dog and wolf behavior are completely different, though, with wolves generally organized around a family pack structure and dogs reliant on humans. When hybridization does occur, it tends to be when human activities – such as habitat encroachment and hunting – disrupt pack dynamics, leading female wolves to strike out on their own and breed with male dogs. People intentionally bred a few “wolf dog”hybrid types in the 20th century, but these are considered the exception.
Luna Belle, a resident of the Wolf Sanctuary of Pennsylvania, which is home to both wolves and wolf dogs. Audrey Lin.
These included 146 ancient dogs and wolves covering about 100,000 years. We also looked at 1,872 modern dogs, including golden retrievers, Chihuahuas, malamutes, basenjis and other well-known breeds, plus more unusual breeds from around the world such as the Caucasian ovcharka and Swedish vallhund.
Finally, we included genomes from about 300 “village dogs.” These are not pets but are free-living animals that are dependent on their close association with human environments.
We traced the evolutionary histories of all of these canids by looking at maternal lineages via their mitochondrial genomes and paternal lineages via their Y chromosomes. We used highly sensitive computational methods to dive into the dogs’ and wolves’ nuclear genomes – that is, the genetic material contained in their cells’ nuclei.
We found the presence of wild wolf genes in most dog genomes and the presence of dog genes in about half of wild wolf genomes. The sign of the wolf was small but it was there, in the form of tiny, almost imperceptible chunks of continuous wolf DNA in dogs’ chromosomes. About two-thirds of breed dogs in our sample had wolf genes from crossbreeding that took place roughly 800 generations ago, on average.
While our results showed that larger, working dogs – such as sled dogs and large guardian dogs that protect livestock – generally have more wolf ancestry, the patterns aren’t universal. Some massive breeds such as the St. Bernard completely lack wolf DNA, but the tiny Chihuahua retains detectable wolf ancestry at 0.2% of its genome. Terriers and scent hounds typically fall at the low end of the spectrum for wolf genes.
We were surprised that every single village dog we tested had pieces of wolf DNA in their genomes. Why would this be the case? Village dogs are free-living animals that make up about half the world’s dogs. Their lives can be tough, with short life expectancy and high infant mortality. Village dogs are also associated with pathogenic diseases, including rabies and canine distemper, making them a public health concern.
More often than predicted by chance, the stretches of wolf DNA we found in village dog genomes contained genes related to olfactory receptors. We imagine that olfactory abilities influenced by wolf genes may have helped these free-living dogs survive in harsh, volatile environments.
The intertwining of dogs and wolves
Because dogs evolved from wolves, all of dogs’ DNA is originally wolf DNA. So when we’re talking about the small pieces of wolf DNA in dog genomes, we’re not referring to that original wolf gene pool that’s been kicking around over the past 20,000 years, but rather evidence for dogs and wolves continuing to interbreed much later in time.
A wolf-dog hybrid with one of each kind of parent would carry 50% dog and 50% wolf DNA. If that hybrid then lived and mated with dogs, its offspring would be 25% wolf, and so on, until we see only small snippets of wolf DNA present.
The situation is similar to one in human genomes: Neanderthals and humans share a common ancestor around half a million years ago. However, Neanderthals and our species, Homo sapiens, also overlapped and interbred in Eurasia as recently as a few thousand generations ago, shortly before Neanderthals disappeared. Scientists can spot the small pieces of Neanderthal DNA in most living humans in the same way we can see wolf genes within most dogs.
Our study updates the previously held belief that hybridization between dogs and wolves is rare; interactions between these two species do have visible genetic traces. Hybridization with free-roaming dogs is considered a threat to conservation efforts of endangered wolves, including Iberian, Italian and Himalayan wolves. However, there also is evidence that dog-wolf mixing might confer genetic advantages to wolves as they adapt to environments that are increasingly shaped by humans.
Though dogs evolved as human companions, wolves have served as their genetic lifeline. When dogs encountered evolutionary challenges such as how to survive harsh climates, scavenge for food in the streets or guard livestock, it appears they’ve been able to tap into wolf ancestry as part of their evolutionary survival kit.
Well thanks to Audrey Lin and Logan Kistler for this very interesting study. So even modern dogs have visible traces of wolf in their DNA. It is yet another example of the ability of modern science to discover facts that were unknown a few decades ago.
An incredible fact, as in the truth, that almost nobody will accept.
Until the 22nd November, 2025, that is last Saturday, I believed this lie. A lie that spoke of the dangers, the hazards, the imminent end of the world as I believed it; as in Climate Change!
Very few of you will change your minds, of that I’m sure.
Nonetheless, I am going to republish a long article that was sent to me by my buddy, Dan Gomez.
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Latest Science Further Exposes Lies About Rising Seas
By Vijay Jayaraj
It’s all too predictable: A jet-setting celebrity or politician wades ceremoniously into hip-deep surf for a carefully choreographed photo op, while proclaiming that human-driven sea-level rise will soon swallow an island nation. Of course, the water is deeper than the video’s pseudoscience, which is as shallow as the theatrics.
The scientific truth is simple: Sea levels are rising, but the rate of rise has not accelerated. A new peer-reviewed study confirms what many other studies have already shown – that the steady rise of oceans is a centuries-long process, not a runaway crisis triggered by modern emissions of carbon dioxide (CO2).
For the past 12,000 years, during our current warm epoch known as the Holocene, sea levels have risen and fallen dramatically. For instance, during the 600-year Little Ice Age, which ended in the mid-19th century, sea levels dropped quite significantly.
The natural warming that began in the late 1600s got to a point around 1800 where loss of glacial ice in the summer began to exceed winter accumulation and glaciers began to shrink and seas to rise. By 1850, full-on glacial retreat was underway.
Thus, the current period of gradual sea-level increase began between 1800-1860, preceding any significant anthropogenic CO2 emissions by many decades. The U.S. Department of Energy’s 2025 critical review on carbon dioxide and climate change confirms this historical perspective.
“There is no good, sufficient or convincing evidence that global sea level rise is accelerating –there is only hypothesis and speculation. Computation is not evidence and unless the results can be practically viewed and measured in the physical world, such results must not be presented as such,” notes Kip Hansen, researcher and former U.S. Coast Guard captain.
New Study Confirms No Crisis
While activists speak of “global sea-level rise,” the ocean’s surface does not behave like water in a bathtub. Regional currents, land movements, and local hydrology all influence relative sea level. This is why local tide gauge data is important. As Hansen warns, “Only actually measured, validated raw data can be trusted. … You have to understand exactly what’s been measured and how.”
In addition, local tide-gauge data cannot be extrapolated to represent global sea level. This is because the geographic coverage of suitable locations for gauges is often poor, with the majority concentrated in the Northern Hemisphere. Latin America and Africa are severely under-represented in the global dataset. Hansen says, “The global tide gauge record is quantitatively problematic, but individual records can be shown as qualitative evidence for a lack of sea-level rise acceleration.”
A new 2025 study provides confirmation. Published in the Journal of Marine Science and Engineering, the study systematically dismantles the narrative of accelerating sea-level rise. It analyzed empirically derived long-term rates from datasets of sufficient length – at least 60 years – and incorporated long-term tide signals from suitable locations.
The startling conclusion: Approximately 95% of monitoring locations show no statistically significant acceleration of sea-level rise. It was found that the steady rate of sea-level rise – averaging around 1 to 2 millimeters per year globally – mirrors patterns observed over the past 150 years.
The study suggests that projections by the Intergovernmental Panel on Climate Change (IPCC), which often predicts rates as high as 3 to 4 millimeters per year by 2100, overestimate the annual rise by approximately 2 millimeters.
This discrepancy is not trivial. It translates into billions of dollars in misguided infrastructure investments and adaptation policies, which assume a far worse scenario than what the data support. Because we now know that local, non-climatic phenomena are a plausible cause of the accelerated sea level rise measured locally.
Rather than pursuing economically destructive initiatives to reduce greenhouse gas emissions on the basis of questionable projections and erroneous climate science, money and time should be invested in supporting coastal communities with accurate data for practical planning to adapt to local sea level rise.
Successful adaptation strategies have existed for centuries in regions prone to flooding and sea-level variations. The Netherlands is an excellent example of how engineering solutions can protect coastal populations even living below sea level.
Rising seas are real but not a crisis. What we have is a manageable, predictable phenomenon to which societies have adapted for centuries. To inflate it into an existential threat is to mislead, misallocate, and ultimately harm the communities that policymakers claim to protect.
This commentary was first published by PJ Media on September 10, 2025.
Vijay Jayaraj is a Science and Research Associate at the CO₂ Coalition, Fairfax, Virginia. He holds an M.S. in environmental sciences from the University of East Anglia and a postgraduate degree in energy management from Robert Gordon University, both in the U.K., and a bachelor’s in engineering from Anna University, India.
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I shall be returning to this important topic soon. Probably by republishing that 2025 Study referred to in the above article.
We must never forget that evolution is always happening.
So without any more from me here is that article.
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If evolution is real, then why isn’t it happening now? An anthropologist explains that humans actually are still evolving
Inuit people such as these Greenlanders have evolved to be able to eat fatty foods with a low risk of getting heart disease. Olivier Morin/AFP via Getty Images
If evolution is real, then why is it not happening now? – Dee, Memphis, Tennessee
Many people believe that we humans have conquered nature through the wonders of civilization and technology. Some also believe that because we are different from other creatures, we have complete control over our destiny and have no need to evolve. Even though lots of people believe this, it’s not true.
Like other living creatures, humans have been shaped by evolution. Over time, we have developed – and continue to develop – the traits that help us survive and flourish in the environments where we live.
I’m an anthropologist. I study how humans adapt to different environments. Adaptation is an important part of evolution. Adaptations are traits that give someone an advantage in their environment. People with those traits are more likely to survive and pass those traits on to their children. Over many generations, those traits become widespread in the population.
The role of culture
We humans have two hands that help us skillfully use tools and other objects. We are able to walk and run on two legs, which frees our hands for these skilled tasks. And we have large brains that let us reason, create ideas and live successfully with other people in social groups.
All of these traits have helped humans develop culture. Culture includes all of our ideas and beliefs and our abilities to plan and think about the present and the future. It also includes our ability to change our environment, for example by making tools and growing food.
Although we humans have changed our environment in many ways during the past few thousand years, we are still changed by evolution. We have not stopped evolving, but we are evolving right now in different ways than our ancient ancestors. Our environments are often changed by our culture.
We usually think of an environment as the weather, plants and animals in a place. But environments include the foods we eat and the infectious diseases we are exposed to.
A very important part of the environment is the climate and what kinds of conditions we can live in. Our culture helps us change our exposure to the climate. For example, we build houses and put furnaces and air conditioners in them. But culture doesn’t fully protect us from extremes of heat, cold and the sun’s rays.
The Turkana people in Kenya have evolved to survive with less water than other people, which helps them live in a desert environment. Tony Karumba/AFP via Getty Images
Here are some examples of how humans have evolved over the past 10,000 years and how we are continuing to evolve today.
The power of the sun’s rays
While the sun’s rays are important for life on our planet, ultraviolet rays can damage human skin. Those of us with pale skin are in danger of serious sunburn and equally dangerous kinds of skin cancer. In contrast, those of us with a lot of skin pigment, called melanin, have some protection against damaging ultraviolet rays from sunshine.
People in the tropics with dark skin are more likely to thrive under frequent bright sunlight. Yet, when ancient humans moved to cloudy, cooler places, the dark skin was not needed. Dark skin in cloudy places blocked the production of vitamin D in the skin, which is necessary for normal bone growth in children and adults.
The amount of melanin pigment in our skin is controlled by our genes. So in this way, human evolution is driven by the environment – sunny or cloudy – in different parts of the world.
The food that we eat
Ten thousand years ago, our human ancestors began to tame or domesticate animals such as cattle and goats to eat their meat. Then about 2,000 years later, they learned how to milk cows and goats for this rich food. Unfortunately, like most other mammals at that time, human adults back then could not digest milk without feeling ill. Yet a few people were able to digest milk because they had genes that let them do so.
Milk was such an important source of food in these societies that the people who could digest milk were better able to survive and have many children. So the genes that allowed them to digest milk increased in the population until nearly everyone could drink milk as adults.
Other people, such as the Inuit in Greenland, have genes that enable them to digest fats without suffering from heart diseases. The Turkana people herd livestock in Kenya in a very dry part of Africa. They have a gene that allows them to go for long periods without drinking much water. This practice would cause kidney damage in other people because the kidney regulates water in your body.
These examples show how the remarkable diversity of foods that people eat around the world can affect evolution.
Like all living creatures, humans have been exposed to many infectious diseases. During the 14th century a deadly disease called the bubonic plague struck and spread rapidly throughout Europe and Asia. It killed about one-third of the population in Europe. Many of those who survived had a specific gene that gave them resistance against the disease. Those people and their descendants were better able to survive epidemics that followed for several centuries.
Some diseases have struck quite recently. COVID-19, for instance, swept the globe in 2020. Vaccinations saved many lives. Some people have a natural resistance to the virus based on their genes. It may be that evolution increases this resistance in the population and helps humans fight future virus epidemics.
As human beings, we are exposed to a variety of changing environments. And so evolution in many human populations continues across generations, including right now.
EarthSky’s Kelly Kizer Whitt captured the northern lights from near Madison, Wisconsin, on November 11, 2025. Kelly wrote: “An amazing night of aurora. In front of the red curtains we had bright green active blobs. One of the better displays I’ve seen.” Thank you, Kelly!
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Ross Stone in Big Pine, California, captured this stunning view on November 11, 2025, and wrote: “The NRAO radio telescope in Owens Valley and the beautiful red aurora in the November sky. This was awesome, and the sky was so bright.” Thank you, Ross!
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EarthSky’s Marcy Curran in Cheyenne, Wyoming, captured a beautiful display of auroras on November 11, 2025. Marcy wrote: “Aurora put on quite a show from Wyoming tonight. Lots of reds and green easily visible to the eye. We live in a semi-rural spot.” Thank you, Marcy!
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Darrell Reese could see the aurora on November 11, 2025, from Ohio! Thank you for sharing your photo, Darrell.
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Ruth Goodwin-Hager in Eureka Springs, Arkansas, shared this image from November 11, 2025, and wrote: “I banged on my neighbors’ doors and recruited others to come outside and see the fabulous lights. It’s been 30 years since I’ve seen northern lights from my backyard like this. Amazing!” Thank you, Ruth!
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Patricia Evans in Seabrook, New Hampshire, captured the aurora on November 11, 2025. Patricia wrote: “Aurora borealis honors Veterans Day. I was afraid that the cloud cover would prevent viewing the aurora borealis but the reds and greens were amazingly intense! What a goosebump moment!” Thank you, Patricia!
This short video I watched last Friday and wanted to share it with you all.
(As I type this, I’m getting an error (Error 153) on my video player. I hope in reality everything will be fine.)
The writing that accompanied the above video is:
Astounding Comet Lemmon Pics From Our Community
Comet Lemmon has been the best comet of 2025. It passed closest to Earth on October 21 and closest to the sun on November 8. As it brightened in our skies, EarthSky community members from around the globe captured spectacular images of the comet. See a compilation of editor’s picks here. Thanks to all who submitted!
This is a one-hour video (as in a YouTube video) from an accredited US healthcare educator.
That is all for today. Just to add that sleep is so important.
‘When we turn the clocks ahead this spring, we’ll lose an hour of sleep—but for many Americans, poor sleep is a nightly problem. Lack of sleep takes a toll on physical and mental health, increasing risk for chronic conditions like high blood pressure and obesity. Our expert panelists will unpack the latest research on rest, including how social and environmental factors can impact our sleep. They’ll explore the connections between race, sleep, and health disparities. And they’ll share advice on how to improve sleep quality for better overall health.’
Last week I went to my doctor to find out what was causing my itching, mainly in my groin and the skin of my forearms.
Dr. Mount told me that I had ringworm. I do not remember having had it before.
The Cleveland Clinic have the details online and it struck me that I should share the information with you. The source of this article is here. I hope very much that sharing this article is alright with Cleveland Clinic.
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Ringworm
Ringworm is an itchy, contagious fungal infection that causes a ring-shaped pattern on your skin. Over-the-counter and prescription treatments can stop the fungus from spreading to other parts of your body or to others.
Overview
Ringworm is a circular-shaped skin rash caused by a fungal infection.
What is ringworm?
You might be surprised to learn that a fungus — and not a worm — causes ringworm. Fungi thrive in warm and humid areas such as locker rooms and public showers. This common and contagious skin infection gets its name from the red, itchy, ring-shaped skin plaque (a type of scaly rash). It spreads easily and through close contact.
You get ringworm from contact with an infected person, animal or object. Ringworm goes by different names depending on which body part it affects. Ringworm on your body is called tinea corporis. This type of ringworm affects your arms, legs, torso and face. Ringworm is treated with antifungal medication available either over the counter or as a prescription.
Types of ringworm
Ringworm has different names based on where it appears on your body — and it can appear just about anywhere. Ringworm infections include:
Athlete’s foot: Also called tinea pedis, this fungal infection causes an itchy, burning skin rash between your toes and on the soles of your feet. Your skin may become scaly and cracked or develop blisters. Sometimes, your feet smell bad.
Jock itch: Tinea cruris, or jock itch, causes a red, itchy rash in your groin, upper thighs or rectum. Some people get blisters.
Scalp ringworm (tinea capitis): This causes scaly, red, itchy bald spots on your scalp. If left untreated, the bald spots can grow bigger and become permanent.
Hands (tinea manuum): Signs of ringworm on your hands include dry, cracked palms and ring-like patches.
Beard (tinea barbae): Ringworm appears on your neck, chin and cheeks. The patches might become crusted over or filled with pus.
Ringworm typically begins as a flat, discolored patch, which may appear red in lighter complexions and brown in darker complexions. The patch has a ring-like or circular shape with a raised, scaly border.
Who gets ringworm?
Ringworm affects people of all ages. You’re more at risk for ringworm if you:
Have a weakened immune system or an autoimmune disease like lupus.
Participate in high-contact sports, such as wrestling (this ringworm is called tinea gladiatorum).
Despite its name, a fungus causes ringworm. This type of fungus naturally lives on your skin, hair and nails. However, when their environment gets hot and damp, the fungi start growing uncontrollably. You can get this infection anytime your skin comes into contact with the ringworm fungus on someone else’s skin.
How contagious is ringworm?
Ringworm is contagious. It can live on your skin, on surfaces and in soil. The main ways ringworm spreads are:
Skin-to-skin contact with a person who has ringworm.
Contact with an infected dog, cat or animal (livestock or pets).
Contact with a contaminated surface, such as a locker room floor or sweaty gym clothes.
Sharing objects with an infected person or animal such as a brush, towel or bedding.
Contaminated soil.
Diagnosis and Tests
How is ringworm diagnosed?
Your healthcare provider can diagnose ringworm by looking at your skin and assessing your symptoms. They may scrape the area to look at the skin cells under a microscope, too. Examining the scales typically confirms ringworm.
Management and Treatment
How is ringworm treated?
Several nonprescription (over-the-counter) and prescription antifungal medications are available to treat ringworm. Antifungals come in various forms like creams, gels or powders. Your healthcare provider can treat more widespread ringworm with oral antifungal medication.
Antifungal creams and powders
Over-the-counter (OTC) antifungal creams, gels or powders typically work well. OTC products include:
If your symptoms get worse or don’t clear after two weeks, you may need an oral prescription medication from your healthcare provider.
Oral medication
Your healthcare provider may write you a prescription for oral antifungal medication if you have ringworm on your scalp or on many parts of your body. Most medications are prescribed for between one and three months. Oral antifungal medications include:
Antifungal shampoo, such as ketoconazole shampoo (Nizoral A-D®), may stop scalp ringworm from spreading. It won’t cure it, but it may help contain the infection. You also need to take a prescribed oral antifungal medication. Unaffected family members may benefit from using the shampoo as well.
Home remedies for ringworm
Home remedies like apple cider vinegar or tea tree have little to no benefit. Apple cider vinegar may cause open sores or inflammation. Tea tree oil has antifungal and antimicrobial properties but its effects aren’t well-known.
Your home may require treatment as well. The ringworm fungus can live on surfaces for months. Disinfectant sprays like Lysol® or bleach can remove the fungus. Wash clothes, sheets and towels in hot water and detergent to prevent ringworm from spreading.
Steroid creams
Corticosteroid creams may help reduce inflammation, but they shouldn’t be used to treat ringworm. In fact, they may worsen the infection.
What cures ringworm?
Mild cases of ringworm clear up within a few weeks. More serious infections may require treatment for six to 12 weeks.
Some other things you can do to promote healing:
Keep the affected area clean and dry.
Apply antifungal lotions, creams or ointments for the entire treatment period.
Avoid touching the area and wash your hands before touching other areas of your body.
Does ringworm go away by itself?
Although ringworm can go away by itself, it’s not common. While ringworm is present on your skin, you’re still contagious to others.
Outlook / Prognosis
Can ringworm come back?
Yes, ringworm can come back. Ringworm will go away if you treat it appropriately. Follow your healthcare provider’s treatment plan until the infection clears completely. If you stop treatment or treatment ends too soon, the infection can come back.
What are the complications of ringworm?
If you suspect you or your child has ringworm, don’t use anti-itch creams containing corticosteroids. These creams weaken your skin’s defenses. They can allow the infection to spread and cover larger sections of skin. On rare occasions, the ringworm fungus goes deeper into your skin, making it even harder to treat.
Scalp ringworm can lead to a painful inflammation called kerion. With kerion, you may develop crusty, pus-filled sores, often with hair loss and scarring.
Prevention
How can I prevent ringworm?
Ringworm thrives in damp, warm areas. The fungus can live on towels, clothes, sheets and household surfaces for months. Preventing ringworm involves:
Changing your socks and underwear daily or more frequently if they become damp or soiled.
Showering immediately after contact sports or exercise.
Wearing sandals or shower shoes at the pool and in public locker rooms and showers.
Drying your skin thoroughly after showering, especially between your toes.
Avoiding sharing towels, washcloths, sheets, clothes, combs or other personal hygiene items.
Washing clothes, athletic gear, sheets and towels in hot water and detergent.
Disinfecting surfaces with bleach or sprays like Lysol®.
Treating pets for ringworm, if they’re infected.
Washing hands thoroughly after contact with animals.
A weak immune system or living in a damp, warm climate increases your risk of a fungal infection.
Living With
When should I call the doctor?
Call your healthcare provider if the ringworm infection:
Appears on your scalp.
Looks infected (redness and swelling).
Occurs during pregnancy.
Spreads to other areas of your body.
Doesn’t improve after using over-the-counter antifungal medication as directed.
What questions should I ask my doctor?
You’re sure to have questions if you or your child develop ringworm. You might ask your healthcare provider:
How did I get ringworm?
How long is ringworm contagious?
Should I (or my child) stay home from work/school until the ringworm infection is gone?
What steps can I take to prevent ringworm from spreading to other parts of my body?
What steps can I take to prevent ringworm from spreading to other people?
What’s the best treatment for ringworm?
Should I avoid any medications or treatments?
What steps can I take to keep from getting ringworm again?
How can I tell if my pet has ringworm?
Should I look out for signs of complications?
Additional Common Questions
Is ringworm an actual worm?
No, ringworm isn’t a worm. It’s a fungal infection that gets its name from its ring-like border.
How does ringworm affect pregnancy?
Ringworm fungus won’t affect your pregnancy. Still, you should check with your healthcare provider before using over-the-counter antifungal creams or powders. Oral antifungal medications appear to be safe to take during pregnancy. Your pregnancy care provider can discuss potential risks and benefits with you.
Can you get ringworm from dogs or cats?
Yes, you can get ringworm from dogs, cats and other animals like cows, goats or horses. You can protect yourself by always washing your hands after playing with or petting animals. If your pet has ringworm, disinfect your pet’s bedding and take extra care to clean surfaces your pet has visited in your home.
How is ringworm different from eczema?
Eczema and many other skin conditions can resemble ringworm. Both ringworm and eczema cause itchy, red skin. Unlike ringworm, eczema isn’t contagious and doesn’t spread from one area to another on your body. Ringworm has a unique, ring-like appearance. Contact a healthcare provider for an appropriate diagnosis.
A note from Cleveland Clinic
Ringworm can be unpleasant, but antifungal medications will help you get rid of the fungus that causes ringworm. The treatment may take time, but it’s important to follow your healthcare provider’s treatment plan for as long as recommended. Ending treatment too soon can cause ringworm to return and make the infection harder to treat. Ask your provider about how you can keep ringworm from spreading to other parts of your body and to other people.
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We were having a small and casual party at our house celebrating Halloween. There were thirteen coming some of them in fancy dress. However, a close neighbour, who was coming with her husband, recommended a cancellation just in case I passed the fungal infection on to someone else.
Thus I have to be patient and keep putting on the cream for at least the next couple of weeks, hoping that in time I will notice the fungus going.
Finally, let me just repeat this from the article by Clevedon: ‘Ringworm is contagious and extremely common. It can affect 20% to 25% of the world’s population at any given time.’
A wonderful documentary of the formation of Planet Earth.
From the website The Earth through time, I quote: The Earth was formed about 4.6 billion years ago. 4.6 billion is 4,600,000.000 years ago. It was formed by collisions of particles in a large cloud of material. Slowly gravity gathered together all these particles of dust and gas and formed larger clumps. These clumps continued to collide and gradually grew bigger and bigger eventually forming the Earth. The earth at this time was very different to how we know it today.
I left a comment on the site: What a wonderful story.. So many comments in support of this fantastic film, and rightly so.
We all live in the Quantenary period. From Wikipedia I quote a small piece:
It follows the Neogene Period and spans from 2.6 million years ago to the present.
I don’t know about you but 2.6 million years ago (Ma) seems like a very long time. But then the prior period was the Neogene that went from 2.6 Ma to 23 Ma.
But if one wants to think ‘old’ then try the Ordovician period:
The Ordovician spans 41.6 million years from the end of the Cambrian Period 486.85 Ma (million years ago) to the start of the Silurian Period 443.1 Ma.
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Just to put us humans into context, human evolution is very much shorter. I have it from six million years onwards. But here are two videos, courtesy of YouTube. The first one is a short one:
Scientists use fossils to reconstruct the evolutionary history of hominins—the group that includes modern humans, our immediate ancestors, and other extinct relatives. Today, our closest living relatives are chimpanzees, but extinct hominins are even closer. Where and when did they live? What can we learn about their lives? Why did they go extinct? Scientists look to fossils for clues.
The second video is a 54-minute one from PBS.
They have both been watched thousands of times.
Now on to today’s post.
ooOOoo
Giant ground sloths’ fossilized teeth reveal their unique roles in the prehistoric ecosystem
Harlan’s ground sloth fossil skeleton excavated and displayed at the La Brea Tar Pits in Los Angeles. Larisa DeSantis
A two-toed sloth at the Nashville Zoo. Larisa R. G. DeSantis
Imagine a sloth. You probably picture a medium-size, tree-dwelling creature hanging from a branch. Today’s sloths – commonly featured on children’s backpacks, stationery and lunch boxes – are slow-moving creatures, living inconspicuously in Central American and South American rainforests.
But their gigantic Pleistocene ancestors that inhabited the Americas as far back as 35 million years ago were nothing like the sleepy tree huggers we know today. Giant ground sloths – some weighing thousands of pounds and standing taller than a single-story building – played vital and diverse roles in shaping ecosystems across the Americas, roles that vanished with their loss at the end of the Pleistocene.
In our new study, published in the journal Biology Letters, we aimed to reconstruct the diets of two species of giant ground sloths that lived side by side in what’s now Southern California. We analyzed remains recovered from the La Brea Tar Pits of what are colloquially termed the Shasta ground sloth (Nothrotheriops shastensis) and Harlan’s ground sloth (Paramylodon harlani). Our work sheds light on the lives of these fascinating creatures and the consequences their extinction in Southern California 13,700 years ago has had on ecosystems.
Dentin dental challenges
Studying the diets of extinct animals often feels like putting together a jigsaw puzzle with only a portion of the puzzle pieces. Stable isotope analyses have revolutionized how paleoecologists reconstruct the diets of many ancient organisms. By measuring the relative ratios of light and heavy carbon isotopes in tooth enamel, we can figure out what kinds of foods an animal ate – for instance, grasses versus trees or shrubs.
Drilling teeth provides a sample for stable isotope analyses. Aditya Kurre
But the teeth of giant ground sloths lack enamel, the highly inorganic and hard outer layer on most animal teeth – including our own. Instead, sloth teeth are made primarily of dentin, a more porous and organic-rich tissue that readily changes its chemical composition with fossilization.
Stable isotope analyses are less dependable in sloths because dentin’s chemical composition can be altered postmortem, skewing the isotopic signatures.
Another technique researchers use to glean information about an animal’s diet relies on analyzing the microscopic wear patterns on its teeth. Dental microwear texture analysis can infer whether an animal mostly ate tough foods such as leaves and grass or hard foods such as seeds and fruit pits. This technique is also tricky when it comes to sloths’ fossilized teeth because signs of wear may be preserved differently in the softer dentin than in harder enamel.
Prior to studying fossil sloths, we vetted dental microwear methods in modern xenarthrans, a group of animals that includes sloths, armadillos and anteaters. This study demonstrated that dentin microwear can reveal dietary differences between leaf-eating sloths and insect-consuming armadillos, giving us confidence that these tools could reveal dietary information from ground sloth fossils.
Distinct dietary niches revealed
Previous research suggested that giant ground sloths were either grass-eating grazers or leaf-eating browsers, based on the size and shape of their teeth. However, more direct measures of diet – such as stable isotopes or dental microwear – were often lacking.
Our new analyses revealed contrasting dental wear signatures between the two co-occurring ground sloth species. The Harlan’s ground sloth, the larger of the two, had microwear patterns dominated by deep pitlike textures. This kind of wear is indicative of chewing hard, mechanically challenging foods such as tubers, seeds, fungi and fruit pits. Our new evidence aligns with skeletal adaptations that suggest powerful digging abilities, consistent with foraging foods both above and below ground.
The fossil teeth of the Harlan’s ground sloth typically showed deeper pitlike textures, bottom, while the Shasta ground sloth teeth had shallower wear patterns, top. DeSantis and Kurre, Biology Letters 2025
In contrast, the Shasta ground sloth exhibited dental microwear textures more akin to those in leaf-eating and woody plant-eating herbivores. This pattern corroborates previous studies of its fossilized dung, demonstrating a diet rich in desert plants such as yucca, agave and saltbush.
Next we compared the sloths’ microwear textures to those of ungulates such as camels, horses and bison that lived in the same region of Southern California. We confirmed that neither sloth species’ dietary behavior overlapped fully with other herbivores. Giant ground sloths didn’t perform the same ecological functions as the other herbivores that shared their landscape. Instead, both ground sloths partitioned their niches and played complementary ecological roles.
Extinctions brought ecological loss
The Harlan’s ground sloth was a megafaunal ecosystem engineer. It excavated soil and foraged underground, thereby affecting soil structure and nutrient cycling, even dispersing seed and fungal spores over wide areas. Anecdotal evidence suggests that some anachronistic fruits – such as the weird, bumpy-textured and softball-size Osage orange – were dispersed by ancient megafauna such as giant ground sloths. When the Pleistocene megafauna went extinct, the loss contributed to the regional restriction of these plants, since no one was around to spread their seeds.
The broader consequence is clear: Megafaunal extinctions erased critical ecosystem engineers, triggering cascading ecological changes that continue to affect habitat resilience today. Our results resonate with growing evidence that preserving today’s living large herbivores and understanding the diversity of their ecological niches is crucial for conserving functional ecosystems.
Studying the teeth of lost giant ground sloths has illuminated not only their diets but also the enduring ecological legacies of their extinction. Today’s sloths, though charming, only hint at the profound environmental influence of their prehistoric relatives – giants that shaped landscapes in ways we are only beginning to appreciate.
Learning from Dogs 
