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Stonehenge stones came from an even older Welsh stone circle
Waun Maun was an ancient Welsh stone circle that had an awful lot in common with Stonehenge.
Ancient Stonehenge stands silently on the U.K.'s Salisbury Plain amidst the continual thrum of cars zipping by on the A303 motorway. It is about as anachronistic as a thing can be, a mysterious object out of time whose mysteries continue to fascinate us.
Bit by bit, Stonehenge's puzzle pieces are falling into place—when its stones were put up, its bluestones' origins in distant Welsh quarries—and a very big one may have just fallen into place. New research suggests that Stonehenge was actually built some 200 km (124 miles) away in Wales where it stood for hundreds of years before being taken apart, transported to its current location, and reassembled with the addition of some local stones.
Lead author of the research, published in Antiquity, is archaeologist Michael Parker Pearson of University College London, who says, "I have been leading projects at Stonehenge since 2003 and this is the culmination of twenty years of research. It's one of the most important discoveries I've ever made."
A mystery of dates solved
Credit: Ankit Sood/Unsplash
The theory has to do with Stonehenge's bluestones. These are the 43 smaller upright stones positioned at the inside of the structure. They're called "bluestones" not because they're normally blue, but because they take on a bit of that hue when they're wet. (The outer, taller, stones at Stonehenge are sarsens, and the stones laying across the tops of other stones are its lintel stones.)
It has been known for some time that the bluestones were dug from a quarry in the Preseli Hills of Wales 200 km away some 5,000 years ago. (The larger sarsen stones are believed to have come from about 15 miles away from Stonehenge.)
There's been a problem with dates, though. The rocks were extracted about 5,000 years ago, between 3400 BC and 3000 BC. That's 300 or 400 years before Stonehenge was built. Where were they all that time? "They're clearly not spending 200 years slowly moving them across the landscape," co-author of the research Joshua Pollard tells Science Magazine.
The earliest writing about the origins of Stonehenge was Geoffrey of Monmouth's c. AD 1136 "History of the Kings of Britain." In it, the author suggests that Stonehenge was constructed from the stones of a dismantled Giants' Dance stone circle atop the mythical Mount Killaraus, having been moved to Salisbury under the command of Merlin. Fantasy, to be sure, but the distant origin of the bluestones may underpin the central idea that these stones were actually repurposed from another place and time.
Credit: Denys Holovatiuk/Adobe Stock/Big Think
The "Stones of Stonehenge" project identified a possible Welsh stone circle in 2010, Waun Mawn, but had not excavated it. In 2017 and 2018, a research team led by Parker Pearson began serious exploration. They identified an ancient megalith quarry nearby and the toppled bluestone remains of the stone circle, estimated to be the third largest yet found after Avebury in Wiltshire and Stanton Drew in Somerset.
At Waun Mawn were socket-shaped pits that likely held other, long-gone bluestones. The researchers used optically simulated luminescence to determine how long ago the sediments buried inside the pits had been exposed to light, and radiocarbon-dated charcoal found inside. The shrine dates back pretty perfectly to 3400 BC, in line with the time the bluestones had been quarried.
The researchers mapped out the likely arrangement of the stone circle by extrapolating between the remaining stones and empty stone sockets. They arrived at a shape that measured about 100 meters across, the same as Stonehenge's original layout, the ditch currently surrounding it. (Stonehenge has been rearranged many times since it was first built.) Waun Mawn, like Stonehenge, was aligned on the midsummer solstice.
The researchers estimate that the missing bluestones were removed between 300 and 400 years after the stone circle was built, around the time Stonehenge was built. "We're quite confident the reason they come down is they've gone to Stonehenge," Parker Pearson tells Science Magazine.
Other clues? One of the Stonehenge bluestones has an unusual shape that matches one of the Waun Mawn pits perfectly. In addition, sone chips found in that pit precisely match that stone at Stonehenge.
There goes the neighborhood
Sometime after 3000 BC, the people living near Waun Maun left — there's little evidence of habitation in the area after about 3400 BC, according to Parker Pearson. "It's as if they just vanished," he says. "Maybe most of the people migrated, taking their stones — their ancestral identities — with them, to start again in this other special place. This extraordinary event may also have served to unite the peoples of east and west Britain."
Analyses of plant and animal remains at Stonehenge indicate that the people who built it spent their early years on the Welsh coast, providing evidence, says Pollard, that "We've got regular contact between the two regions."
Parker Pearson suggests that maybe the people who built Stonehenge incorporated the bluestones from Waun Mawn for one of two reasons: to have something of their former home in their new one, or to use the bluestones as symbols of their authority, thus entitling it to respect and power among their new neighbors.
In any event, Pearson suspects there's more to the story. Waun Mawn's stones may not be the only transplants at Stonehenge:
"With an estimated 80 bluestones put up on Salisbury Plain at Stonehenge and nearby Bluestonehenge, my guess is that Waun Mawn was not the only stone circle that contributed to Stonehenge. Maybe there are more in Preseli waiting to be found. Who knows? Someone might be lucky enough to find them."
Scientists are using bioelectronic medicine to treat inflammatory diseases, an approach that capitalizes on the ancient "hardwiring" of the nervous system.
- Bioelectronic medicine is an emerging field that focuses on manipulating the nervous system to treat diseases.
- Clinical studies show that using electronic devices to stimulate the vagus nerve is effective at treating inflammatory diseases like rheumatoid arthritis.
- Although it's not yet approved by the US Food and Drug Administration, vagus nerve stimulation may also prove effective at treating other diseases like cancer, diabetes and depression.
The nervous system’s ancient reflexes<p>You accidentally place your hand on a hot stove. Almost instantaneously, your hand withdraws.</p><p>What triggered your hand to move? The answer is <em>not</em> that you consciously decided the stove was hot and you should move your hand. Rather, it was a reflex: Skin receptors on your hand sent nerve impulses to the spinal cord, which ultimately sent back motor neurons that caused your hand to move away. This all occurred before your "conscious brain" realized what happened.</p><p>Similarly, the nervous system has reflexes that protect individual cells in the body.</p><p>"The nervous system evolved because we need to respond to stimuli in the environment," said Dr. Tracey. "Neural signals don't come from the brain down first. Instead, when something happens in the environment, our peripheral nervous system senses it and sends a signal to the central nervous system, which comprises the brain and spinal cord. And then the nervous system responds to correct the problem."</p><p>So, what if scientists could "hack" into the nervous system, manipulating the electrical activity in the nervous system to control molecular processes and produce desirable outcomes? That's the chief goal of bioelectronic medicine.</p><p>"There are billions of neurons in the body that interact with almost every cell in the body, and at each of those nerve endings, molecular signals control molecular mechanisms that can be defined and mapped, and potentially put under control," Dr. Tracey said in a <a href="https://www.youtube.com/watch?v=AJH9KsMKi5M" target="_blank">TED Talk</a>.</p><p>"Many of these mechanisms are also involved in important diseases, like cancer, Alzheimer's, diabetes, hypertension and shock. It's very plausible that finding neural signals to control those mechanisms will hold promises for devices replacing some of today's medication for those diseases."</p><p>How can scientists hack the nervous system? For years, researchers in the field of bioelectronic medicine have zeroed in on the longest cranial nerve in the body: the vagus nerve.</p>
The vagus nerve<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYyOTM5OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NTIwNzk0NX0.UCy-3UNpomb3DQZMhyOw_SQG4ThwACXW_rMnc9mLAe8/img.jpg?width=1245&coordinates=0%2C0%2C0%2C0&height=700" id="09add" class="rm-shortcode" data-rm-shortcode-id="f38dbfbbfe470ad85a3b023dd5083557" data-rm-shortcode-name="rebelmouse-image" data-width="1245" data-height="700" />
Electrical signals, seen here in a synapse, travel along the vagus nerve to trigger an inflammatory response.
Credit: Adobe Stock via solvod<p>The vagus nerve ("vagus" meaning "wandering" in Latin) comprises two nerve branches that stretch from the brainstem down to the chest and abdomen, where nerve fibers connect to organs. Electrical signals constantly travel up and down the vagus nerve, facilitating communication between the brain and other parts of the body.</p><p>One aspect of this back-and-forth communication is inflammation. When the immune system detects injury or attack, it automatically triggers an inflammatory response, which helps heal injuries and fend off invaders. But when not deployed properly, inflammation can become excessive, exacerbating the original problem and potentially contributing to diseases.</p><p>In 2002, Dr. Tracey and his colleagues discovered that the nervous system plays a key role in monitoring and modifying inflammation. This occurs through a process called the <a href="https://www.nature.com/articles/nature01321" target="_blank" rel="noopener noreferrer">inflammatory reflex</a>. In simple terms, it works like this: When the nervous system detects inflammatory stimuli, it reflexively (and subconsciously) deploys electrical signals through the vagus nerve that trigger anti-inflammatory molecular processes.</p><p>In rodent experiments, Dr. Tracey and his colleagues observed that electrical signals traveling through the vagus nerve control TNF, a protein that, in excess, causes inflammation. These electrical signals travel through the vagus nerve to the spleen. There, electrical signals are converted to chemical signals, triggering a molecular process that ultimately makes TNF, which exacerbates conditions like rheumatoid arthritis.</p><p>The incredible chain reaction of the inflammatory reflex was observed by Dr. Tracey and his colleagues in greater detail through rodent experiments. When inflammatory stimuli are detected, the nervous system sends electrical signals that travel through the vagus nerve to the spleen. There, the electrical signals are converted to chemical signals, which trigger the spleen to create a white blood cell called a T cell, which then creates a neurotransmitter called acetylcholine. The acetylcholine interacts with macrophages, which are a specific type of white blood cell that creates TNF, a protein that, in excess, causes inflammation. At that point, the acetylcholine triggers the macrophages to stop overproducing TNF – or inflammation.</p><p>Experiments showed that when a specific part of the body is inflamed, specific fibers within the vagus nerve start firing. Dr. Tracey and his colleagues were able to map these relationships. More importantly, they were able to stimulate specific parts of the vagus nerve to "shut off" inflammation.</p><p>What's more, clinical trials show that vagus nerve stimulation not only "shuts off" inflammation, but also triggers the production of cells that promote healing.</p><p>"In animal experiments, we understand how this works," Dr. Tracey said. "And now we have clinical trials showing that the human response is what's predicted by the lab experiments. Many scientific thresholds have been crossed in the clinic and the lab. We're literally at the point of regulatory steps and stages, and then marketing and distribution before this idea takes off."<br></p>
The future of bioelectronic medicine<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYxMDYxMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjQwOTExNH0.uBY1TnEs_kv9Dal7zmA_i9L7T0wnIuf9gGtdRXcNNxo/img.jpg?width=980" id="8b5b2" class="rm-shortcode" data-rm-shortcode-id="c005e615e5f23c2817483862354d2cc4" data-rm-shortcode-name="rebelmouse-image" data-width="2000" data-height="1125" />
Vagus nerve stimulation can already treat Crohn's disease and other inflammatory diseases. In the future, it may also be used to treat cancer, diabetes, and depression.
Credit: Adobe Stock via Maridav<p>Vagus nerve stimulation is currently awaiting approval by the US Food and Drug Administration, but so far, it's proven safe and effective in clinical trials on humans. Dr. Tracey said vagus nerve stimulation could become a common treatment for a wide range of diseases, including cancer, Alzheimer's, diabetes, hypertension, shock, depression and diabetes.</p><p>"To the extent that inflammation is the problem in the disease, then stopping inflammation or suppressing the inflammation with vagus nerve stimulation or bioelectronic approaches will be beneficial and therapeutic," he said.</p><p>Receiving vagus nerve stimulation would require having an electronic device, about the size of lima bean, surgically implanted in your neck during a 30-minute procedure. A couple of weeks later, you'd visit, say, your rheumatologist, who would activate the device and determine the right dosage. The stimulation would take a few minutes each day, and it'd likely be unnoticeable.</p><p>But the most revolutionary aspect of bioelectronic medicine, according to Dr. Tracey, is that approaches like vagus nerve stimulation wouldn't come with harmful and potentially deadly side effects, as many pharmaceutical drugs currently do.</p><p>"A device on a nerve is not going to have systemic side effects on the body like taking a steroid does," Dr. Tracey said. "It's a powerful concept that, frankly, scientists are quite accepting of—it's actually quite amazing. But the idea of adopting this into practice is going to take another 10 or 20 years, because it's hard for physicians, who've spent their lives writing prescriptions for pills or injections, that a computer chip can replace the drug."</p><p>But patients could also play a role in advancing bioelectronic medicine.</p><p>"There's a huge demand in this patient cohort for something better than they're taking now," Dr. Tracey said. "Patients don't want to take a drug with a black-box warning, costs $100,000 a year and works half the time."</p><p>Michael Dowling, president and CEO of Northwell Health, elaborated:</p><p>"Why would patients pursue a drug regimen when they could opt for a few electronic pulses? Is it possible that treatments like this, pulses through electronic devices, could replace some drugs in the coming years as preferred treatments? Tracey believes it is, and that is perhaps why the pharmaceutical industry closely follows his work."</p><p>Over the long term, bioelectronic approaches are unlikely to completely replace pharmaceutical drugs, but they could replace many, or at least be used as supplemental treatments.</p><p>Dr. Tracey is optimistic about the future of the field.</p><p>"It's going to spawn a huge new industry that will rival the pharmaceutical industry in the next 50 years," he said. "This is no longer just a startup industry. [...] It's going to be very interesting to see the explosive growth that's going to occur."</p>
Researchers figure out the average temperatures of the last ice age on Earth.
- A new study analyzes fossil data to find the average temperatures during the last Ice Age.
- This period of time, about 20,000 years ago, had the average temperature of about 46 degrees Fahrenheit (7.8 C).
- The study has implications for understanding climate change.
Surface air temperatures during the last ice age.
Credit: Jessica Tierney, University of Arizona
"The Expanse" is the best vision I've ever seen of a space-faring future that may be just a few generations away.
- Want three reasons why that headline is justified? Characters and acting, universe building, and science.
- For those who don't know, "The Expanse" is a series that's run on SyFy and Amazon Prime set about 200 years in the future in a mostly settled solar system with three waring factions: Earth, Mars, and Belters.
- No other show I know of manages to use real science so adeptly in the service of its story and its grand universe building.
Credit: "The Expanse" / Syfy<p>Now, I get it if you don't agree with me. I love "Star Trek" and I thought "Battlestar Galactica" (the new one) was amazing and I do adore "The Mandalorian". They are all fun and important and worth watching and thinking about. And maybe you love them more than anything else. But when you sum up the acting, the universe building, and the use of real science where it matters, I think nothing can beat "The Expanse". And with a <a href="https://www.rottentomatoes.com/tv/the_expanse" target="_blank">Rotten Tomato</a> average rating of 93%, I'm clearly not the only one who feels this way.</p><p>Best.</p><p>Show.</p><p>Ever. </p>
Contrary to what some might think, the brain is a very plastic organ.
As with many other physicians, recommending physical activity to patients was just a doctor chore for me – until a few years ago. That was because I myself was not very active.