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Scientists solve the origin of Stonehenge’s sarsen stones
Most of Stonehenge's megaliths, called sarens, came from West Woods, Wiltshire.
- Researchers have known Stonehenge's smaller bluestones came from Preseli Hills, Wales, but the source of its sarsens has remained a mystery.
- Using chemical analysis, scientists found a matching source at West Woods, approximately 16 miles north of the World Heritage Site.
- But mysteries remain, such as why that site was chosen.
Many mysteries surround Stonehenge. Who built it and what purpose did it serve? Why that arrangement of megaliths and lentels? How did Neolithic people move and erect such massive stones using 5,000-year-old technology? Because Stonehenge's builders left us no written record, historians, archaeologists, enthusiasts, conspiracy theorists, and outright cranks have tried for centuries to translate their prehistoric silence into answers.
As scientific tools and techniques have advanced, we've learned to better discern the forensic clues left behind in the megaliths, inhumed bodies, and landscape of the Salisbury Plain. Today, scientists have traced Stonehenge's "bluestones"—smaller dolerite stones found in the monument's interior—to quarries in Preseli Hills, Wales. They've also established that the bluestones likely served as grave markers for the people buried there, also from Wales.
Thanks to our scientific tools, and a reclaimed piece of history, another Stonehenge mystery has been solved. Scientists have pinpointed the source area for most of the monument's extant sarsens. And no, aliens did not carry these megaliths with tractor beams to create an interstellar landing pad. Sorry, cranks. Stonehenge's origin is far more terrestrial, found in a little spot near Marlborough Downs.
Discovering Stonehenge's signature
In 1958, engineers undertook the task of re-erecting a Stonehenge trilithon that fell in 1797. Three cores drilled into a sarsen disappeared soon after.
"Sarsen" is the common term for the giant sandstone—more specifically, duricrust silcrete—megaliths that enwreathe Stonehenge. Fifty-two of an estimated 80 sarsens remain today. They form both the interior horseshoe and the uprights and lintels of the outer circle, as well as peripheral stones like the Heel and Slaughter Stones. The largest sarsens stand at about 30 feet tall and weigh around 25 tons.
The immense size of these boulders sits at the center of one of Stonehenge's most enticing enigmas. How did people, using only Neolithic technology, manage to move and prop up such massive stones? A major piece to that puzzle has been their source, as the answer would inform scientists on the opportunities and challenges facing the builders as they moved the sarsens.
To find that piece, David Nash, the study's lead author and a professor at Brighton University, and his team analyzed the sarsens using a portable X-ray fluorescence spectrometer. This non-intrusive analysis allowed them to generate initial chemical characterizations for the stones' 34 chemical elements.
"Until recently we did not know it was possible to provenance a stone like sarsen," Nash said in a release. "It has been really exciting to use 21st century science to understand the Neolithic past and answer a question that archaeologists have been debating for centuries."
To further hone in on the source area, the team needed to generate high-resolution chemical signatures by analyzing a sample. Of course, the idea of tearing a sample out of this World Heritage Site would be near sacrilege. Luckily, a previously lost piece of history had recently been returned to the British people.
In 1958, a restoration program re-erected a Stonehenge trilithon that fell in 1797. After lifting the sarsens, engineers discovered cracks in one of the uprights (Stone 58). They drilled out three cores from the stone and inserted metal ties to reinforce its integrity. The holes were filled with sarsen plugs to hide the intrusion. However, the three cores disappeared.
Flash forward to 2018. Robert Phillips, an 89-year-old U.S. citizen and on-site worker during the restoration, returned one of the three cores. Nash and his team were granted permission to sample a piece from "Phillips' core." They used a plasma mass spectrometer to create a chemical signature for the monument, one they could compare to potential source sites across southern Britain.
They found a match in West Woods, Wiltshire. Fifty of Stonehenge's 52 sarsens share a chemical signature with the stones in this area, strongly suggesting they were sourced there. The area also sports a high concentration of evidence for early Neolithic activity, adding to its plausibility.
"To be able to pinpoint the area that Stonehenge's builders used to source their materials around 2,500 BC is a real thrill," Susan Greaney, senior properties historian at English Heritage, told the BBC. "While we had our suspicions that Stonehenge's sarsens came from the Marlborough Downs, we didn't know for sure, and with areas of sarsens across Wiltshire, the stones could have come from anywhere."
She added the evidence showed "how carefully considered and deliberate the building of this phase of Stonehenge was."
The study was published in Science Advances.
For every answer, another question
A view of Stonehenge during the Summer Solstice.
(Photo: Wikimedia Commons)
Thanks to Nash and his team, scientists now know the source of Stonehenge's sarsens. This clue can help them solve other Stonehenge mysteries. That most of the stones were sourced from one location, the study notes, suggests that they were erected at about the same time. It also reveals the routes the Neolithic builders had to traverse with their heavy loads.
But questions remain. Why did the builders choose West Woods when the Salisbury Plain is dense with sarsen? Why were two megaliths (Stones 26 and 160) sourced elsewhere? And were the missing stones gathered from West Woods or elsewhere?
These questions only touch on the sarsens. The question that intrigues so many of the monument's visitors remains hotly debated: Who built Stonehenge and why? Was it a burial site for the Stone age elite? A monument marking British unification? A Druid Mecca? We don't know, but as scientific tools advance, we may be able to break the prehistoric silence that has laid over Stonehenge for so long.
How would the ability to genetically customize children change society? Sci-fi author Eugene Clark explores the future on our horizon in Volume I of the "Genetic Pressure" series.
- A new sci-fi book series called "Genetic Pressure" explores the scientific and moral implications of a world with a burgeoning designer baby industry.
- It's currently illegal to implant genetically edited human embryos in most nations, but designer babies may someday become widespread.
- While gene-editing technology could help humans eliminate genetic diseases, some in the scientific community fear it may also usher in a new era of eugenics.
Tribalism and discrimination<p>One question the "Genetic Pressure" series explores: What would tribalism and discrimination look like in a world with designer babies? As designer babies grow up, they could be noticeably different from other people, potentially being smarter, more attractive and healthier. This could breed resentment between the groups—as it does in the series.</p><p>"[Designer babies] slowly find that 'everyone else,' and even their own parents, becomes less and less tolerable," author Eugene Clark told Big Think. "Meanwhile, everyone else slowly feels threatened by the designer babies."</p><p>For example, one character in the series who was born a designer baby faces discrimination and harassment from "normal people"—they call her "soulless" and say she was "made in a factory," a "consumer product." </p><p>Would such divisions emerge in the real world? The answer may depend on who's able to afford designer baby services. If it's only the ultra-wealthy, then it's easy to imagine how being a designer baby could be seen by society as a kind of hyper-privilege, which designer babies would have to reckon with. </p><p>Even if people from all socioeconomic backgrounds can someday afford designer babies, people born designer babies may struggle with tough existential questions: Can they ever take full credit for things they achieve, or were they born with an unfair advantage? To what extent should they spend their lives helping the less fortunate? </p>
Sexuality dilemmas<p>Sexuality presents another set of thorny questions. If a designer baby industry someday allows people to optimize humans for attractiveness, designer babies could grow up to find themselves surrounded by ultra-attractive people. That may not sound like a big problem.</p><p>But consider that, if designer babies someday become the standard way to have children, there'd necessarily be a years-long gap in which only some people are having designer babies. Meanwhile, the rest of society would be having children the old-fashioned way. So, in terms of attractiveness, society could see increasingly apparent disparities in physical appearances between the two groups. "Normal people" could begin to seem increasingly ugly.</p><p>But ultra-attractive people who were born designer babies could face problems, too. One could be the loss of body image. </p><p>When designer babies grow up in the "Genetic Pressure" series, men look like all the other men, and women look like all the other women. This homogeneity of physical appearance occurs because parents of designer babies start following trends, all choosing similar traits for their children: tall, athletic build, olive skin, etc. </p><p>Sure, facial traits remain relatively unique, but everyone's more or less equally attractive. And this causes strange changes to sexual preferences.</p><p>"In a society of sexual equals, they start looking for other differentiators," he said, noting that violet-colored eyes become a rare trait that genetically engineered humans find especially attractive in the series.</p><p>But what about sexual relationships between genetically engineered humans and "normal" people? In the "Genetic Pressure" series, many "normal" people want to have kids with (or at least have sex with) genetically engineered humans. But a minority of engineered humans oppose breeding with "normal" people, and this leads to an ideology that considers engineered humans to be racially supreme. </p>
Regulating designer babies<p>On a policy level, there are many open questions about how governments might legislate a world with designer babies. But it's not totally new territory, considering the West's dark history of eugenics experiments.</p><p>In the 20th century, the U.S. conducted multiple eugenics programs, including immigration restrictions based on genetic inferiority and forced sterilizations. In 1927, for example, the Supreme Court ruled that forcibly sterilizing the mentally handicapped didn't violate the Constitution. Supreme Court Justice Oliver Wendall Holmes wrote, "… three generations of imbeciles are enough." </p><p>After the Holocaust, eugenics programs became increasingly taboo and regulated in the U.S. (though some states continued forced sterilizations <a href="https://www.uvm.edu/~lkaelber/eugenics/" target="_blank">into the 1970s</a>). In recent years, some policymakers and scientists have expressed concerns about how gene-editing technologies could reanimate the eugenics nightmares of the 20th century. </p><p>Currently, the U.S. doesn't explicitly ban human germline genetic editing on the federal level, but a combination of laws effectively render it <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">illegal to implant a genetically modified embryo</a>. Part of the reason is that scientists still aren't sure of the unintended consequences of new gene-editing technologies. </p><p>But there are also concerns that these technologies could usher in a new era of eugenics. After all, the function of a designer baby industry, like the one in the "Genetic Pressure" series, wouldn't necessarily be limited to eliminating genetic diseases; it could also work to increase the occurrence of "desirable" traits. </p><p>If the industry did that, it'd effectively signal that the <em>opposites of those traits are undesirable. </em>As the International Bioethics Committee <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">wrote</a>, this would "jeopardize the inherent and therefore equal dignity of all human beings and renew eugenics, disguised as the fulfillment of the wish for a better, improved life."</p><p><em>"Genetic Pressure Volume I: Baby Steps"</em><em> by Eugene Clark is <a href="http://bigth.ink/38VhJn3" target="_blank">available now.</a></em></p>
A leading British space scientist thinks there is life under the ice sheets of Europa.
- A British scientist named Professor Monica Grady recently came out in support of extraterrestrial life on Europa.
- Europa, the sixth largest moon in the solar system, may have favorable conditions for life under its miles of ice.
- The moon is one of Jupiter's 79.
Neil deGrasse Tyson wants to go ice fishing on Europa<div class="rm-shortcode" data-media_id="GLGsRX7e" data-player_id="FvQKszTI" data-rm-shortcode-id="f4790eb8f0515e036b24c4195299df28"> <div id="botr_GLGsRX7e_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/GLGsRX7e-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"></script> </div>
Water Vapor Above Europa’s Surface Deteced for First Time<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="9c4abc8473e1b89170cc8941beeb1f2d"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/WQ-E1lnSOzc?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
A unique exoplanet without clouds or haze was found by astrophysicists from Harvard and Smithsonian.
- Astronomers from Harvard and Smithsonian find a very rare "hot Jupiter" exoplanet without clouds or haze.
- Such planets were formed differently from others and offer unique research opportunities.
- Only one other such exoplanet was found previously.
Munazza Alam – a graduate student at the Center for Astrophysics | Harvard & Smithsonian.
Credit: Jackie Faherty
Jupiter's Colorful Cloud Bands Studied by Spacecraft<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="8a72dfe5b407b584cf867852c36211dc"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/GzUzCesfVuw?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Scientists discover burrows of giant predator worms that lived on the seafloor 20 million years ago.
- Scientists in Taiwan find the lair of giant predator worms that inhabited the seafloor 20 million years ago.
- The worm is possibly related to the modern bobbit worm (Eunice aphroditois).
- The creatures can reach several meters in length and famously ambush their pray.
A three-dimensional model of the feeding behavior of Bobbit worms and the proposed formation of Pennichnus formosae.
Credit: Scientific Reports
Beware the Bobbit Worm!<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="1f9918e77851242c91382369581d3aac"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/_As1pHhyDHY?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
The idea behind the law was simple: make it more difficult for online sex traffickers to find victims.