With water levels in Spain’s Valdecañas reservoir drained to 28 percent capacity, a sprawling prehistoric monument has emerged from the dry lake bed: the “Spanish Stonehenge,” also known as the dolmen of Guadalperal. The massive megalithic complex is believed by archeologists to date back to 5000 B.C., according to Reuters. Rediscovered in modern times by German researcher Hugo Obermaier in 1926, the structure has only fully popped up out of the waters four times since then. “It’s a surprise,” expert Enrique Cedillo told Reuters, “it’s a rare opportunity to be able to access it.” Little is known about the civilization that erected them, nor what they were for, with popular theories including that they were grave-markers, trading posts, ritual sites, or dire water-level warnings, prophesying famines to come. The dolmen was last visible in 2019. The peninsula where the structure is erected is at its driest point in 1,200 years, with conditions expected to worsen, according to a study cited by Reuters.
The Antikythera mechanism is an ancient shoebox-sized device that is sometimes called the world’s oldest computer for its ability to perform astronomical calculations.
Discovered by sponge divers off the Greek island of Antikythera in 1901, the remains of the mechanism are now preserved in the National Archaeological Museum in Athens. Only 82 fragments, consisting of about one-third of the original mechanism, survive today, researchers wrote in a 2021 study published in the journal Scientific Reports (opens in new tab). It was built around 2,200 years ago.
What did the Antikythera mechanism do?
The mechanism was capable of performing different calculations, and it could help track the motions of the sun, moon and five of the planets; it could even tell when athletic competitions, such as the Olympics, were set to take place, the researchers wrote. “It was a mechanical computer of bronze gears that used ground-breaking technology to make astronomical predictions, by mechanizing astronomical cycles and theories,” the team wrote in the journal article.
Since the discovery of the Antikythera mechanism, scholars have been trying to understand the device. And although they have made considerable progress, many questions remain unanswered. For example, researchers still aren’t sure who made it. Some scholars have posited that the Greek inventor Archimedes (287 B.C. to 212 B.C.) was the mechanism’s creator, but this is uncertain. The inscriptions on the mechanism are written in Greek.
Whoever made the device would have had to know a great deal about astronomy, metallurgy and mechanology, Aristeidis Voulgaris, team leader of the Functional Reconstruction of Antikythera Mechanism (Frame) project, told Live Science in an email. This project aims to reconstruct what the mechanism originally looked like and gain a better understanding of it. They also would have needed “great hand dexterity,” he noted.
An engraving illustration of the last hour of Archimedes, the mathematician who died in 212 B.C. or 211 B.C. when the Romans captured Syracuse, Sicily. (Image credit: mikroman6 via Getty Images)
The recovered fragments of the mechanism contained writing and inscriptions, and over the past two decades, scientists have been able to read more of these Greek inscriptions using high-tech imaging methods, such as 3D X-ray scanning. This has enabled them to learn more about how the mechanism worked.
CT scans “revealed inscriptions describing the motions of the sun, moon and all five planets known in antiquity and how they were displayed at the front as an ancient Greek cosmos,” the researchers wrote in the Scientific Reports article. The mechanism used “cycles from Babylonian astronomy, mathematics from Plato’s Academy and ancient Greek astronomical theories,” the researchers wrote.
The mechanism represents “a level of technology exceeding anything else of the kind for which we have either physical remains or detailed descriptions from antiquity,” Alexander Jones, a professor of the history of the exact sciences in antiquity at New York University’s Institute for the Study of the Ancient World, wrote in his book “A Portable Cosmos: Revealing the Antikythera Mechanism, Scientific Wonder of the Ancient World (opens in new tab)” (Oxford University Press, 2017).
What did the Antikythera mechanism look like?
More pieces of the Antikythera Mechanism at the Archaeological Museum in Athens. (Image credit: LOUISA GOULIAMAKI/AFP via Getty Images)
The authors of the Scientific Reports article found that someone viewing the front of the mechanism would have seen dials that showed the movements of the moon, sun, lunar nodes (points where the moon’s orbit crosses the ecliptic, the path the sun appears to take through the constellations), Mercury, Venus, Mars, Jupiter and Saturn, as well as the Zodiac calendar.
The back of the mechanism had dials showing the Metonic cycle (a 19-year cycle after which the phases of the moon occur on the same days of the year), the Callippic cycle (a period of 76 years, equal to four Metonic cycles), the Olympiad cycle (when the Olympics were held every four years), the Saros cycle (a period of more than 18 years between lunar eclipses) and the exeligmos (a period of more than 54 years, or three Saros cycles).
Between the front and back of the mechanism were a vast array of gears, designed in such a way that all the dials would depict the correct timing of all the cycles.
“Suppose a user of the Antikythera Mechanism wants to check eclipse predictions for a particular month some years ahead. The user winds the mechanism forwards to the desired date, as shown on one of its calendars,” Tony Freeth, a researcher with the Antikythera Mechanism Research Project, wrote in a paper published in 2014 in the journal PLOS One (opens in new tab).
Antikythera mechanism shipwreck
This massive marble head found by the latest excavations at the Antikythera wreck site is thought to represent the Greek demigod Heracles. (Image credit: Nikos Giannoulakis/Hellenistic Ministry of Culture and Sports/Swiss School of Archaeology in Greece)
Though the ship that held the Antikythera mechanism was discovered more than a century ago, the wreck has not been fully excavated. The size of the ship that carried it is unclear and just how widely the artifacts are dispersed is also somewhat uncertain. Its location and depth make it hard to excavate, according to the Woods Hole Oceanographic Institution (opens in new tab) (WHOI). The site is at an angle on the seafloor around 130 to 165 feet (40 to 50 m) below the surface, meaning it’s too deep for scuba divers to excavate for long but too shallow to be investigated by remotely operated vehicles, according to the WHOI.
Despite these difficulties a new program of excavation is being carried out by a team of archaeologists and new artifacts continue to be found, shedding light on what the ship, which likely sank around 65 B.C. was like.Their finds include a bronze arm that was once attached to a statue, a board game, possible remains of an ancient throne, and a marble statue head of Hercules, Live Science previously reported.
Researchers have noted that many of the artifacts were luxury goods intended for the wealthy. So far, the recent excavations have not uncovered any new remains of the mechanism.
Excavations in 2016 at the Antikythera shipwreck found a nearly intact skull, including the cranial parietal bones. (Image credit: Brett Seymour, EUA/WHOI/ARGO)
In 2016, archaeologists unearthed the ancient skeleton of a male at the shipwreck, Live Science reported at the time. Recently, scientists have been trying to extract DNA to learn more about the man.
Researchers still aren’t sure why the mechanism was on the ship in the first place. “This was not an object one would casually subject to the risk of travel,” Jones wrote in his book. While the mechanism may not have been a one-of-a-kind device, it would surely have been something of considerable value. One possibility is that a technician was transporting the device to its intended owner, Jones wrote, noting that a storm likely caused the ship to sink, taking the mechanism down with it. Where the ship came from and where it was going to is a subject of ongoing research and debate among scholars.
Antikythera mechanism’s ‘start date’
Scholars are still debating the Antikythera mechanism’s exact “start date,” the earliest date on which all calculations made on the mechanism are based. Research published in March 2022 on the preprint server arXiv (opens in new tab) proposed Dec. 22, 178 B.C. as the mechanism’s start date. Researchers noted that on that day, there was a lunar eclipse, followed by the winter solstice, followed by a festival dedicated to the goddess Isis. While Isis was an Egyptian goddess, she was highly regarded in Greece at this time.
However, other (opens in new tab) teams of scholars have (opens in new tab) proposed May 12, 204 B.C. as the most likely start date, noting that on that day, a lunar eclipse would have been visible in Greece, and that this date is closer to the life of Archimedes. It’s possible that he or someone who worked in his workshop could have built this device.
Additional resources
Bibliography
Freeth, T. et al. (2021) “A Model of the Cosmos in the ancient Greek Antikythera Mechanism” Scientific Reports 5821
https://doi.org/10.1038/s41598-021-84310-w (opens in new tab)
Freeth, T. (2014) “Eclipse Prediction on the Ancient Greek Astronomical Calculating Machine Known as the Antikythera Mechanism” PlosOne
https://doi.org/10.1371/journal.pone.0103275 (opens in new tab)
Jones, A. (2017) “A Portable Cosmos: Revealing the Antikythera Mechanism, Scientific Wonder of the Ancient World” Oxford University Press
Voulgaris, A. et al (2022) “The Initial Calibration Date of the Antikythera Mechanism after the Saros spiral mechanical Apokatastasis” arXiv
https://arxiv.org/abs/2203.15045 (opens in new tab)
The Kao Gong Ji, the oldest known technical encyclopedia, was written around 300 BC and is part of a larger text called The Rites of Zhou. The ancient text includes six chemistry formulas for mixing bronze and lists items like swords, bells, axes, knives and mirrors, as well as how to make them.
For the past 100 years, researchers have struggled to translate two of the main ingredients, which are listed as “jin”and “xi.” Experts believed these words translated to copper and tin, which are key components in the bronze-making process. When researchers tried to re-create the recipes, however, the resulting metal didn’t match up with the composition of ancient Chinese artifacts.
Now, two researchers believe they have accurately identified the true meaning behind the mystery ingredients. The journal Antiquity published their findings on Tuesday.
The revelation allows for a better understanding of ancient bronze production — and opens up new questions about when this process began, given that large-scale bronze production happened long before the six recipes were shared in the Kao Gong Ji, said study coauthor Ruiliang Liu, curator of the Early China Collection at the British Museum in London.
In modern Chinese, jin means gold. But the ancient meaning of the word could be copper, copper alloy or even just metal, which is why it has been difficult to determine the specific ingredients.
“These recipes were used in the largest bronze industry in Eurasia during this period,” said Liu in a statement. “Attempts to reconstruct these processes have been made for more than a hundred years, but have failed.”
Chemical analysis
Liu and lead study author Mark Pollard analyzed the chemical composition of Chinese coins minted close to when the Kao Gong Ji was written. Pollard is the Edward Hall Professor of Archaeological Science at Oxford University and director of the Research Laboratory for Archaeology and the History of Art.
Previously, researchers had thought the coins were made by diluting copper with tin and lead.
The analysis showed that the chemical composition of the coins was a result of mixing two pre-prepared metal alloys, one made of copper, tin and lead, and the other copper and lead.
The two researchers concluded jin and xi were likely premixed metal alloys.
“For the first time in more than 100 years of scholarship, we have produced a viable explanation of how to interpret the recipes for making bronze objects in early China given in the (Kao Gong Ji),” Pollard said in a statement.
The findings have shown that ancient Chinese bronze-making relied on combining alloys instead of pure metals and that metalsmithing was more complex than previously thought.
“It indicates an additional step — the production of pre-prepared alloys — in the manufacturing process of copper-alloy objects in early China,” Liu said. “This represents an additional but previously unknown layer in the web of metal production and supply in China.”
Archaeologically, this additional step would have remained invisible if not for chemical analysis, the researchers said.
“Understanding the alloying practice is crucial for us to understand the exquisite bronze ritual vessels as well as the underlying mass production in Shang and Zhou societies,” Liu said.
Using this type of analysis could help researchers decipher other texts about ancient metallurgy from different cultures and regions in the future, the researchers said.
A little under 13 billion years ago, a large blue star lit up the early cosmos.
Across countless light years of expanding space that light has shone, reduced to shadow wherever it met dust and rock.
What little remained of those ancient photons was pulled out of shape by the growth of space itself, warping and bending as it skirted the gravity wells of interceding stars and galaxies.
Finally, earlier this year, some of this light fell upon the lens of a telescope orbiting a small, water-logged planet, giving us a look at a truly ancient star.
The images provided by Hubble were extraordinary. But scientists who saw it said this light was special enough to use a different telescope to get a closer look.
Coded WHL0137-LS, though better known for its Tolkienesque name Earendel, the star now holds the record for the earliest, most distant star we humans have ever had the fortune to catch sight of.
So on 30 July 2022, the James Webb Space Telescope turned its attention to the corner of the sky dominated by the constellation Cetus, where this dim, twisted arc of ancient sunlight was last seen.
We’re excited to share the first JWST image of Earendel, the most distant star known in our universe, lensed and magnified by a massive galaxy cluster. It was observed Saturday by JWST program 2282. pic.twitter.com/YoZZKRsdzf
— Cosmic Spring JWST (@CosmicSprngJWST) August 2, 2022
Its dim rays are so bent out of shape, so thin and stretched, it’s hard to tell much about the object that made them. So far we know Earendel is probably hot and big – somewhere between 50 and 100 solar masses. This makes it likely to burn out faster, winking out in a supernova just millions of years after it first sparked to life.
You can see Earendel as it’s lensed by the cluster, WHL0137-08, in the center of the image! Here is a zoom-in on the star itself! Stay tuned for an update from the science team! pic.twitter.com/3mfYZ0WTNg
— Cosmic Spring JWST (@CosmicSprngJWST) August 2, 2022
Igniting around 900 million years after the Big Bang, it’s unlikely to be among the very first stars in the Universe, though still emerged at a time when heavier elements were somewhat scarce.
Whatever more we can learn from its spectrum will have to wait a little longer. With the JWST capable of discerning details that the Hubble space telescope can’t, astronomers might soon be able to glean a few more clues about this new record holder.
Earendel’s tired light has traveled so far to get here. Whatever it has to say, we’re sure it’s worth waiting a little longer to listen to.
A depiction of Earth, first without an inner core; second, with an inner core beginning to grow, around 550 million years ago; third, with an outermost and innermost inner core, around 450 million years ago. University of Rochester researchers used paleomagnetism to determine these two key dates in the history of the inner core, which they believe restored the planet’s magnetic field just before the explosion of life on Earth. Credit: University of Rochester illustration / Michael Osadciw
New paleomagnetic research suggests Earth’s solid inner core formed 550 million years ago and restored our planet’s magnetic field.
Swirling liquid iron in the Earth’s outer core, located approximately 1,800 miles beneath our feet, generates our planet’s protective magnetic field, called the magnetosphere. Although this magnetic field is invisible, it is vital for life on Earth’s surface. That’s because the magnetosphere shields the planet from solar wind—streams of radiation from the sun.
However, about 565 million years ago, the magnetic field’s strength dropped to 10 percent of its strength today. Then, mysteriously, the magnetic field bounced back, regaining its strength just before the Cambrian explosion of multicellular life on Earth.
What caused the magnetosphere to bounce back?
This rejuvenation happened within a few tens of millions of years according to new research from scientists at the University of Rochester. This is very rapid on geological timescales and coincided with the formation of Earth’s solid inner core, suggesting that the core is likely a direct cause.
“The inner core is tremendously important,” says John Tarduno, the William R. Kenan, Jr., Professor of Geophysics in the Department of Earth and Environmental Sciences and dean of research for Arts, Sciences & Engineering at Rochester. “Right before the inner core started to grow, the magnetic field was at the point of collapse, but as soon as the inner core started to grow, the field was regenerated.”
In the paper, published on July 19, 2022, in the journal Nature Communications, the scientists determined several key dates in the inner core’s history, including a more precise estimate of its age. The research provides new clues about the history and future evolution of Earth and how it became a habitable planet, as well as the evolution of other planets in the solar system.
Earth’s layers and structure.
Unlocking information in ancient rocks
Earth is made up of layers: the crust, where life exists; the mantle, Earth’s thickest layer; the molten outer core; and the solid inner core, which is, in turn, composed of an outermost inner core and an innermost inner core.
Earth’s magnetic field is generated in its outer core. Swirling liquid iron there causes electric currents, driving a phenomenon called the geodynamo that produces the magnetic field.
Because of the magnetic field’s relationship to Earth’s core, scientists have been attempting for decades to ascertain how Earth’s magnetic field and core have changed throughout our planet’s history. They cannot directly measure the magnetic field due to the location and extreme temperatures of materials in the core. Fortunately, minerals that rise to Earth’s surface contain tiny magnetic particles that lock in the direction and intensity of the magnetic field at the time the minerals cool and solidify from their molten state.
To better constrain the age and growth of the inner core, Tarduno and his team used a CO2 laser and the lab’s superconducting quantum interference device (SQUID) magnetometer to analyze feldspar crystals from the rock anorthosite. These crystals have minute magnetic needles within them that are “perfect magnetic recorders,” Tarduno says.
By studying the magnetism locked in ancient crystals—a field known as paleomagnetism—the researchers determined two new important dates in the history of the inner core:
550 million years ago: the time at which the magnetic field began to renew rapidly after a near collapse 15 million years before that. The researchers attribute the rapid renewal of the magnetic field to the formation of a solid inner core that recharged the molten outer core and restored the magnetic field’s strength.
450 million years ago: the time at which the growing inner core’s structure changed, marking the boundary between the innermost and outermost inner core. These changes in the inner core coincide with changes around the same time in the structure of the overlying mantel, due to plate tectonics on the surface.
“Because we constrained the inner core’s age more accurately, we could explore the fact that the present-day inner core is actually composed of two parts,” Tarduno says. “Plate tectonic movements on Earth’s surface indirectly affected the inner core, and the history of these movements is imprinted deep within Earth in the inner core’s structure.”
Avoiding a Mars-like fate
A better understanding of the dynamics and growth of the inner core and the magnetic field has important implications, not only in uncovering Earth’s past and predicting its future, but in unraveling the ways in which other planets might form magnetic shields and sustain the conditions necessary to harbor life.
Researchers believe that
“This research really highlights the need to have something like a growing inner core that sustains a magnetic field over the entire lifetime—many billions of years—of a planet.”
Reference: “Early Cambrian renewal of the geodynamo and the origin of inner core structure” by Tinghong Zhou, John A. Tarduno, Francis Nimmo, Rory D. Cottrell, Richard K. Bono, Mauricio Ibanez-Mejia, Wentao Huang, Matt Hamilton, Kenneth Kodama, Aleksey V. Smirnov, Ben Crummins and Frank Padgett III, 19 July 2022,
A group of scientists has concluded that ancient Europeans drank milk for millennia despite the digestive problems it may have caused, casting doubt on theories on how humans evolved to tolerate it.
Scientists have long speculated that an enzyme needed to avoid any gastrointestinal discomfort developed rapidly in populations where domesticating dairy animals was prevalent.
People who could tolerate milk, that theory goes, gained a new source of calories and protein and passed on their genes to more healthy offspring than those without the genetic trait — known as lactase persistence — that allows themto digest the sugar in milk into adulthood.
But a new study has offered a radically different theory, arguing that side effects such as gas, bloating and intestinal cramps weren’t enough on their own to move the evolutionary needle on the genetic mutation.
“Prehistoric people in Europe may have started consuming milk from domesticated animals thousands of years before they evolved the gene to digest it,” the study’s authors said.
The study, published in the journal Nature, was produced in collaboration with more than 100 scientists across a range of fields including genetics, archaeology and epidemiology. The scientists mapped out estimated milk consumption in Europe from approximately 9,000 years ago to 500 years ago.
By analyzing animal fat residues in pottery from hundreds of archaeological sites, alongside DNA samples harvested from ancient skeletons, the researchers concluded that lactase persistence was not common until around 1,000 B.C., nearly 4,000 years after it was first detected.
And, rather than in times of abundance, they argue that it was during famine and epidemics that having the mutation became critical to survival: when undigested lactose could lead to serious intestinal illnesses and death.
Using archaeological records to identify periods where populations shrank, they concluded that people were more likely to drink milk when all other food sources had been exhausted, and that during those periods, diarrhea was more likely to escalate from a mild to a deadly condition.
George Davey Smith, an epidemiologist at the University of Bristol, who teamed up with the researchers on an analysis of contemporary data on milk and lactase persistence in current populations, said the study raises “fascinating questions” about whether some people who believe they are lactose intolerant “might actually be fine if they drank milk.”
About a quarter of Americans are lactose intolerant. In a lawsuit filed last year, a group of American doctors asked why the U.S. Department of Agriculture’s dietary guidelines recommend so much dairy — suggesting that the federal agency is looking out for the interests of the meat and dairy industries rather than the health of Americans.
USDA dietary guidelines are driven by milk marketing concerns — not nutrition — lawsuit alleges
Previous studies have suggested that populations had to rely heavily on dairy before individuals adapted to tolerate it in abundance. A smaller study in 2014 found the variation that allows humans to digest lactose didn’t appear in Hungarian DNA samples until 3,000 years ago, whereas it may have cropped up as far back as 7,000 years in places such as Ireland where cheesemaking became abundant.
Amber Milan, an expert in dairy intolerance at the University of Auckland, said the idea that the lactase mutation became important to survival only when Europeans began enduring epidemics and famines is a “sound theory” and “supported by previous research of drivers of genetic selection.”
She added, however, that she is not sure the new study “entirely rules out that widespread milk consumption was the evolutionary force behind lactose tolerance” — partly because the genetic data was collected from Biobank, a British biomedical database of genetic and health information from some 500,000 people.
The authors have also focused on the major European genetic variant for lactase persistence — which, while appropriate for this study, “does potentially miss other genetic variants that result in lactase persistence,” Milan said.
A depiction of Earth, first without an inner core; second, with an inner core beginning to grow, around 550 million years ago; third, with an outermost and innermost inner core, around 450 million years ago. University of Rochester researchers used paleomagnetism to determine these two key dates in the history of the inner core, which they believe restored the planet’s magnetic field just before the explosion of life on Earth. Credit: University of Rochester / Michael Osadciw
Approximately 1,800 miles beneath our feet, swirling liquid iron in the Earth’s outer core generates our planet’s protective magnetic field. This magnetic field is invisible but is vital for life on Earth’s surface because it shields the planet from solar wind—streams of radiation from the sun.
About 565 million years ago, however, the magnetic field’s strength decreased to 10 percent of its strength today. Then, mysteriously, the field bounced back, regaining its strength just before the Cambrian explosion of multicellular life on Earth.
What caused the magnetic field to bounce back?
According to new research from scientists at the University of Rochester, this rejuvenation happened within a few tens of millions of years—rapid on geological timescales—and coincided with the formation of Earth’s solid inner core, suggesting that the core is likely a direct cause.
“The inner core is tremendously important,” says John Tarduno, the William R. Kenan, Jr., Professor of Geophysics in the Department of Earth and Environmental Sciences and dean of research for Arts, Sciences & Engineering at Rochester. “Right before the inner core started to grow, the magnetic field was at the point of collapse, but as soon as the inner core started to grow, the field was regenerated.”
In the paper, published in Nature Communications, the researchers determined several key dates in the inner core’s history, including a more precise estimate for its age. The research provides clues about the history and future evolution of Earth and how it became a habitable planet, as well as the evolution of other planets in the solar system.
Unlocking information in ancient rocks
Earth is composed of layers: the crust, where life is situated; the mantle, Earth’s thickest layer; the molten outer core; and the solid inner core, which is in turn composed of an outermost inner core and an innermost inner core.
Earth’s magnetic field is generated in its outer core, where swirling liquid iron causes electric currents, driving a phenomenon called the geodynamo that produces the magnetic field.
Because of the magnetic field’s relationship to Earth’s core, scientists have been trying for decades to determine how Earth’s magnetic field and core have changed throughout our planet’s history. They cannot directly measure the magnetic field due to the location and extreme temperatures of materials in the core. Fortunately, minerals that rise to Earth’s surface contain tiny magnetic particles that lock in the direction and intensity of the magnetic field at the time the minerals cool from their molten state.
To better constrain the age and growth of the inner core, Tarduno and his team used a CO2 laser and the lab’s superconducting quantum interference device (SQUID) magnetometer to analyze feldspar crystals from the rock anorthosite. These crystals have minute magnetic needles within them that are “perfect magnetic recorders,” Tarduno says.
By studying the magnetism locked in ancient crystals—a field known as paleomagnetism—the researchers determined two new important dates in the history of the inner core:
550 million years ago: the time at which the magnetic field began to renew rapidly after a near collapse 15 million years before that. The researchers attribute the rapid renewal of the magnetic field to the formation of a solid inner core that recharged the molten outer core and restored the magnetic field’s strength.
450 million years ago: the time at which the growing inner core’s structure changed, marking the boundary between the innermost and outermost inner core. These changes in the inner core coincide with changes around the same time in the structure of the overlying mantel, due to plate tectonics on the surface.
“Because we constrained the inner core’s age more accurately, we could explore the fact that the present-day inner core is actually composed of two parts,” Tarduno says. “Plate tectonic movements on Earth’s surface indirectly affected the inner core, and the history of these movements is imprinted deep within Earth in the inner core’s structure.”
Avoiding a Mars-like fate
Better understanding the dynamics and growth of the inner core and the magnetic field has important implications, not only in uncovering Earth’s past and predicting its future, but in unraveling the ways in which other planets might form magnetic shields and sustain the conditions necessary to harbor life.
Researchers believe that Mars, for example, once had a magnetic field, but the field dissipated, leaving the planet vulnerable to solar wind and the surface without oceans. While it is unclear whether the absence of a magnetic field would have caused Earth to meet the same fate, “Earth certainly would’ve lost much more water if Earth’s magnetic field had not been regenerated,” Tarduno says. “The planet would be much drier and very different than the planet today.”
In terms of planetary evolution, then, the research emphasizes the importance of a magnetic shield and a mechanism to sustain it, he says.
“This research really highlights the need to have something like a growing inner core that sustains a magnetic field over the entire lifetime—many billions of years—of a planet.”
New research provides evidence of strong early magnetic field around Earth
More information:
Tinghong Zhou et al, Early Cambrian renewal of the geodynamo and the origin of inner core structure, Nature Communications (2022). DOI: 10.1038/s41467-022-31677-7
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How did Earth avoid a Mars-like fate? Ancient rocks hold clues (2022, July 25)
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Steve Smith in a Hawaiian cave passage filled with roots of the Kaʻu district on the Island of Hawai`i. Credit: Kenneth Ingham
Centuries-Old Lava Caves of Hawaiʻi Island Contain Thousands of Unknown Bacterial Species
Higher bacterial diversity than scientists expected has been uncovered in the lava caves, lava tubes, and geothermal vents on the big island of Hawaiʻi. The findings have been reported in a new study published today (July 21, 2022) in the journal Frontiers in Microbiology.
This research investigates the variety and interactions within these microbial ecosystems, which illustrate how life may have existed on
“This study points to the possibility that more ancient lineages of bacteria, like the phylum Chloroflexi, may have important ecological ‘jobs,’ or roles,” said first author Dr. Rebecca D Prescott of
Thick microbial mats hang under a rock ledge in steam vents that run along the Eastern Rift Zone on Hawaiʻi Island. Credit: Jimmy Saw
The harshest conditions—the geothermal sites—were expected to have lower diversity than the more established and habitable lava tubes. While the diversity was indeed found to be lower, the team of researchers was surprised to discover that the interactions within these communities were more complex than in locations with higher diversity.
“This leads to the question, do extreme environments help create more interactive microbial communities, with microorganisms more dependent on each other?” said Prescott. “And if so, what is it about extreme environments that helps to create this?”
Since Chloroflexi, and another class called Acidobacteria, were present at nearly all of the locations, they may play essential roles in these communities. However, these were not the most abundant bacteria, and the individual communities from the different sites showed large variations in the diversity and complexity of the microbial interactions. Counterintuitively, the most abundant groups, Oxyphotobacteria and Actinobacteria, were not often ‘hub’ species, suggesting that their roles may be less important to the overall structure of the community.
More questions than answers
Since the current study was based on the partial sequencing of one gene, it cannot accurately determine the species of microbes or their ‘jobs’ in the community. Therefore, further research is needed to help reveal the individual species that are present, as well as to better understand these bacteria’s roles in the environment.
A stalactite formation in a Hawaiian cave system from this study with copper minerals and white microbial colonies. Despite the fact that copper is toxic to many organisms, this formation hosts a microbial community. Credit: Kenneth Ingham
“Overall, this study helps to illustrate how important it is to study microbes in co-culture, rather than growing them alone (as isolates),” said Prescott. “In the natural world, microbes do not grow in isolation. Instead, they grow, live, and interact with many other microorganisms in a sea of chemical signals from those other microbes. This then can alter their gene expression, affecting what their jobs are in the community.”
Beyond the insights about past, or even future, life on Mars, bacteria from volcanic environments can also be useful in understanding how microbes turn volcanic rock (basalt) into soils, as well as bioremediation, biotechnology, and sustainable resource management.
Reference: “Islands Within Islands: Bacterial Phylogenetic Structure and Consortia in Hawaiian Lava Caves and Fumaroles” by Rebecca D. Prescott, Tatyana Zamkovaya, Stuart P. Donachie, Diana E. Northup, Joseph J. Medley, Natalia Monsalve, Jimmy H. Saw, Alan W. Decho, Patrick S. G. Chain and Penelope J. Boston, 21 July 2022, Frontiers in Microbiology. DOI: 10.3389/fmicb.2022.934708
Funding: NASA Headquarters, George Washington University
Brain injury patients’ lives are saved thanks to ancient Egyptian-style operation where a hole is drilled into their skull to reduce swelling
Op that dates from days of the pharaohs could save thousands who suffer brain injuries every year
It involves making a hole in skull to ease swelling and pressure on the brain – in a similar procedure to one used by ancient Egyptians as a religious ritual
Study has found patients who have the surgery – decompressive craniectomy – are a fifth more likely to survive than those given standard medication
By Cameron Henderson For The Mail On Sunday
Published: | Updated:
An operation that dates from the days of the pharaohs could save thousands who suffer brain injuries every year.
It involves making a hole in the skull to ease swelling and pressure on the brain – in a similar procedure to one used by ancient Egyptians as a religious ritual.
A new study has found that patients who have the surgery, called a decompressive craniectomy, are a fifth more likely to survive than those given standard medication.
Professor Peter Hutchinson, a consultant neurosurgeon at Addenbrooke’s Hospital in Cambridge, who led on the study, said: ‘Without any doubt, the operation can save lives.’
An operation that dates from the days of the pharaohs could save thousands who suffer brain injuries every year. It involves making a hole in the skull to ease swelling and pressure on the brain – in a similar procedure to one used by ancient Egyptians as a religious ritual
Some 160,000 Britons are admitted to hospital each year with brain injuries, often caused by traffic collisions and falls.
When the brain is injured, fluid can collect inside the skull, causing pressure that can restrict the blood supply. Eventually brain cells begin to die, causing memory loss, paralysis and even death.
Patients are usually treated with drugs, but if these don’t work, doctors may opt for a procedure called a ventriculostomy, in which a tube is inserted through a hole made in the skull to drain excess fluid.
Some 160,000 Britons are admitted to hospital each year with brain injuries, often caused by traffic collisions and falls
In a craniectomy, a larger 5in hole is made in the back of the skull and part of the membrane surrounding the brain is removed, instantly reducing pressure.
The skin is then stitched back over the hole. Once the injury has healed, the hole in the skull is covered with a titanium plate.
Previous research suggested that decompressive craniectomy carries a high risk of leaving patients disabled, but in a new study of 408 patients, published in the journal JAMA Neurology, patients who underwent craniectomy were 21 per cent more likely to survive for two years than those treated with drugs, and were more likely to make a good recovery.
Russell Ramplin, 42, from Ipswich, had a craniectomy in 2020 after a motorbike crash. He has since made a near full recovery and earlier this year he had the missing section of his skull replaced with a titanium plate at Addenbrooke’s.
He says: ‘I’m back on my feet again. I’ve got a job, a place to live and I’ve got no pain.
‘It saved my life. I’m sure it could save others.’
The lateral view of the skull unearthed from Red Dear Cave. Credit: Xueping Ji
For the first time, researchers successfully sequenced the genome of ancient human fossils from the Late Pleistocene in southern China. The data, published July 14 in the journal Current Biology, suggests that the mysterious hominin belonged to an extinct maternal branch of modern humans that might have contributed to the origin of Native Americans.
“Ancient DNA technique is a really powerful tool,” Su says. “It tells us quite definitively that the Red Deer Cave people were modern humans instead of an archaic species, such as Neanderthals or Denisovans, despite their unusual morphological features,” he says.
The researchers compared the genome of these fossils to that of people from around the world. They found that the bones belonged to an individual that was linked deeply to the East Asian ancestry of Native Americans. Combined with previous research data, this finding led the team to propose that some of the southern East Asia people had traveled north along the coastline of present-day eastern China through Japan and reached Siberia tens of thousands of years ago. They then crossed the Bering Strait between the continents of Asia and North America and became the first people to arrive in the New World.
The journey to making this discovery started over three decades ago, when a group of archaeologists in China discovered a large set of bones in the Maludong, or Red Deer Cave, in southern China’s Yunnan Province. Carbon dating showed that the fossils were from the Late Pleistocene about 14,000 years ago, a period of time when modern humans had migrated to many parts of the world.
The reproduced portrait of the Red Deer Cave People or Mengziren. Credit: Xueping Ji
From the cave, researchers recovered a hominin skull cap with characteristics of both modern humans and archaic humans. For example, the shape of the skull resembled that of Neanderthals, and its brain appeared to be smaller than that of modern humans. As a result, some anthropologists had thought the skull probably belonged to an unknown archaic human species that lived until fairly recently or to a hybrid population of archaic and modern humans.
In 2018, in collaboration with Xueping Ji, an archaeologist at Yunnan Institute of Cultural Relics and Archaeology, Bing Su at Kunming Institute of Zoology, Chinese Academy of Sciences, and his colleagues successfully extracted ancient DNA from the skull. Genomic sequencing shows that the hominin belonged to an extinct maternal lineage of a group of modern humans whose surviving decedents are now found in East Asia, the Indo-China peninsula, and Southeast Asia islands.
The finding also shows that during the Late Pleistocene, hominins living in southern East Asia had rich genetic and morphologic diversity, the degree of which is greater than that in northern East Asia during the same period. It suggests that early humans who first arrived in eastern Asia had initially settled in the south before some of them moved to the north, Su says.
The excavation site of Maludong (Red Deer Cave). Credit: Xueping Ji
“It’s an important piece of evidence for understanding early human migration,” he says.
Next, the team plans to sequence more ancient human DNA by using fossils from southern East Asia, especially ones that predated the Red Deer Cave people.
“Such data will not only help us paint a more complete picture of how our ancestors migrate but also contain important information about how humans change their physical appearance by adapting to local environments over time, such as the variations in skin color in response to changes in sunlight exposure,” Su says.
Middle Pleistocene human skull reveals variation and continuity in early Asian humans
More information:
Bing Su, A Late Pleistocene human genome from Southwest China, Current Biology (2022). DOI: 10.1016/j.cub.2022.06.016. www.cell.com/current-biology/f … 0960-9822(22)00928-9
Citation:
DNA from ancient population in Southern China suggests Native Americans’ East Asian roots (2022, July 14)
retrieved 15 July 2022
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