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4 of the biggest archeological finds of 2021 — including a 'game changer' – NPR

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The pandemic has made the future uncertain, but archaeologists never stopped working to discover our past.

AFP Contributor/AFP via Getty Images

AFP Contributor/AFP via Getty Images

Global lockdowns and political strife made it a tough year for archaeologists, at least in terms of getting out there on excavation sites.

But despite what many might think, archaeology isn’t just about sifting through soil in search of lost artifacts.

A lot of the work actually happens far away from the dig site, in labs where scientists are analyzing these found objects, trying to piece together humankind’s unrecorded history.

So while archaeologists spent less time out digging, 2021 was still a good year in archaeology.

We take a look at some of the biggest advancements in archaeology from this year. We spoke to the Trowelblazers, a group of four female archaeologists of different specialties dedicated to highlighting the historic and integral roll of women in the “digging sciences”.

They told us what they thought were some of the most important developments in their field in 2021.

Neanderthals may have been more human than we think

Dr. Rebecca Wragg Sykes is an archaeologist who specializes in Neanderthals, a relative of modern humans that went extinct about 40,000 years ago.

She chose to highlight a paper published last April in the journal Scientific Reports about the discovery of 100,000-year-old Neanderthal footprints on a coastal area of the Spanish Iberian peninsula.

Researchers used modern imaging technology to gather data and analyze the 100,000-year-old footprints.

Eduardo Mayoral et al/Scientific Reports

Eduardo Mayoral et al/Scientific Reports

While these aren’t the first Neanderthal footprints to be discovered, they are very special.

“This is especially nice, because it’s a group – mixed age, including children, some of which are quite young. They seem to be sort of foraging around on the edge of a lagoon,” Wragg Sykes said.

The diversity in age is key here and actually helps to challenge a common assumption that Neanderthals foraged in solitude, with the adults peeling off from the group to find food for the children.

The discovery instead gives support to the theory that hunting and gathering might have been a family affair, involving a collaborative and intergenerational effort.

Adorably, the paper also noted that some of the footprints which belonged to children were “grouped in a chaotic arrangement,” as if they were playing.

“That’s an angle on the Neanderthal life that we don’t often get to see,” Wragg Sykes said, adding that the discovery helps give a sense of humanity to this not-so-distant human relative.

The powerful women of ancient Spain

A 3,700-year-old set of woman’s remains adorned with precious objects was found in the La Almoloya grave and suggests female power in society.

Arqueoecologia Social Mediterrània Research Group/Universitat Autònoma de Barcelona

Arqueoecologia Social Mediterrània Research Group/Universitat Autònoma de Barcelona

Dr. Brenna Hasset is a biological archaeologist who describes her specialty as fascinating and exciting, while also a bit macabre.

“My job is essentially digging up dead people. So I study the lives of people in the past, to try and understand how they lived, how they died.”

This year, Hasset was most excited by a paper published in the journal Antiquity about a 3,700-year-old grave site found in Spain. One tomb at the site held the remains of a man and a woman, in addition to a number of personal belongings.

The excavators found that the woman’s remains were adorned with a number of precious objects, such as bracelets, necklaces, and a silver diadem, or crown.

Hasset said you can tell what someone meant to their community by the things they’re buried with.

Arqueoecologia Social Mediterrània Research Group/Universitat Autònoma de Barcelona

Arqueoecologia Social Mediterrània Research Group/Universitat Autònoma de Barcelona

Hasset notes that a lot can be learned about someone’s role in society by the things they’re buried with. The presence of such precious objects suggests that the woman held a high social status and perhaps even political power.

“We always think of these societies being run by sort of manly men, and their pointy objects to enforce power,” Hasset said. “When we see these women with these exceptional artifacts, are we actually seeing signs of a type of women’s power?”

The million-year-old mammoth

DNA from mammoth teeth found preserved in permafrost in Siberia is over 1,000,000 years old and was the oldest to ever be sequenced.

Koichi Kamoshida/Getty Images

Koichi Kamoshida/Getty Images

Dr. Victoria Herridge isn’t exactly an archaeologist, she’s actually a paleontologist who specializes in ancient elephant species.

She chose to highlight a paper published in Nature last February that reported the successful sequencing of DNA retrieved from mammoth teeth found in permafrost in Siberia. The DNA is more than a million years old and is the oldest DNA to ever be successfully sequenced. The discovery challenges the previously held theory that there was only one mammoth species in Siberia at the time, instead showing multiple genetic lineages. The researchers spoke with NPR’s All Things Considered last February.

However, for Herridge, it was the age of the DNA that got her most excited, which has broad implications for paleontology, archaeology and a number of adjacent fields, she said.

“To me, it’s just like a proper game changer!”

Herridge said this DNA was especially valuable because the last million years were a key period for understanding the course of mammal evolution.

She points out that while the cold conditions of the permafrost helped preserve the DNA, the sheer age of the samples is groundbreaking nonetheless.

“It shows that you can get genetic information way, way, way further back in time that we previously thought was possible.”

Herridge made sure to highlight one of the paper co-authors, Patrícia Pečnerová, whose ingenious lab techniques made sequencing the DNA possible.

“I think it shows that the things that maybe were previously dismissed as being impossible may not be impossible. And so maybe we shouldn’t rule out the chances with decent, careful lab work and developing techniques.”

How to not lose track of our tracks

Dr. Suzanne Pilaar Birch is an associate professor of archaeology and geography at the University of Georgia in Athens.

She chose to feature a paper published recently in Nature about a renewed analysis of footprints discovered in the 1970s in Tanzania. Researchers returned to the site and upon reexamination determined that the tracks belonged to an early hominin species, not to an animal species like a bear, as was previously thought.

The prints, which are an estimated 3.6 million years old, are the oldest evidence of bipedal locomotion of a human ancestor. NPR’s Nell Greenfieldboyce covered these findings earlier this month.

However, Pilaar Birch highlighted this story not because of its extraordinary findings, but rather for how it highlights the need for better preservation of our archaeological assets.

“This was work that was done 50 years ago,” Pilaar Birch said, “[But] the casts that had been made from this trackway had actually been lost.”

She notes that if the casts had been properly taken care of, it may not have been necessary to go back to the site and that we might have been able to draw this important conclusion earlier.

Pilaar Birch said there was a great need to improve long-term preservation of archaeological assets and record management.

While many institutions struggle with funding, she said there was a movement to change that, especially in the area of data preservation and aggregation.

“It’s definitely an area that we’re seeing a lot of advancement and the National Science Foundation is very supportive and funding new database initiatives.”

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Ancient life may be just one possible explanation for Mars rover's latest discovery – CTV News

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In the search for life beyond Earth, NASA’s Curiosity rover has been on a nearly decade-long mission to determine if Mars was ever habitable for living organisms.

A new analysis of sediment samples collected by the rover revealed the presence of carbon — and the possible existence of ancient life on the red planet is just one potential explanation for why it may be there.

Carbon is the foundation for all of life on Earth, and the carbon cycle is the natural process of recycling carbon atoms. On our home planet, carbon atoms go through a cycle as they travel from the atmosphere to the ground and back to the atmosphere. Most of our carbon is in rocks and sediment and the rest is in the global ocean, atmosphere and organisms, according to NOAA, or the National Oceanic and Atmospheric Administration.

That’s why carbon atoms — with their cycle of recycling — are tracers of biological activity on Earth. So they could be used to help researchers determine if life existed on ancient Mars.

When these atoms are measured inside another substance, like Martian sediment, they can shed light on a planet’s carbon cycle, no matter when it occurred.

Learning more about the origin of this newly detected Martian carbon could also reveal the process of carbon cycling on Mars.

A study detailing these findings published Monday in the journal Proceedings of the National Academy of Sciences.

SECRETS IN THE SEDIMENT

Curiosity landed in Gale Crater on Mars in August 2012. The 154.5-kilometre crater, named for Australian astronomer Walter F. Gale, was probably formed by a meteor impact between 3.5 billion and 3.8 billion years ago. The large cavity likely once held a lake, and now it includes a mountain called Mount Sharp. The crater also includes layers of exposed ancient rock.

For a closer look, the rover drilled to collect samples of sediment across the crater between August 2012 and July 2021. Curiosity then heated these 24 powder samples to around 1,562 degrees Fahrenheit (850 degrees Celsius) in order to separate elements. This caused the samples to release methane, which was then analyzed by another instrument in the rover’s arsenal to show the presence of stable carbon isotopes, or carbon atoms.

Some of the samples were depleted in carbon while others were enriched. Carbon has two stable isotopes, measured as either carbon 12 or carbon 13.

“The samples extremely depleted in carbon 13 are a little like samples from Australia taken from sediment that was 2.7 billion years old,” said Christopher H. House, lead study author and professor of geosciences at Pennsylvania State University, in a statement.

“Those samples were caused by biological activity when methane was consumed by ancient microbial mats, but we can’t necessarily say that on Mars because it’s a planet that may have formed out of different materials and processes than Earth.”

In lakes on Earth, microbes like to grow in big colonies that essentially form mats just under the surface of the water.

THREE POSSIBLE CARBON ORIGINS

The varied measurements of these carbon atoms could suggest three very different things about ancient Mars. The origin of the carbon is likely due to cosmic dust, ultraviolet degradation of carbon dioxide, or the ultraviolet degradation of biologically produced methane.

“All three of these scenarios are unconventional, unlike processes common on Earth,” according to the researchers.

The first scenario involves our entire solar system passing through a galactic dust cloud, something that occurs every 100 million years, according to House. The particle-heavy cloud could trigger cooling events on rocky planets.

“It doesn’t deposit a lot of dust,” House said. “It is hard to see any of these deposition events in the Earth record.”

But it’s possible that during an event like this, the cosmic dust cloud would have lowered temperatures on ancient Mars, which may have had liquid water. This could have caused glaciers to form on Mars, leaving a layer of dust on top of the ice. When the ice melted, the layer of sediment including carbon would have remained. While it’s entirely possible, there is little evidence for glaciers in Gale Crater and the study authors said it would require further research.

The second scenario involves the conversion of carbon dioxide on Mars into organic compounds, such as formaldehyde, due to ultraviolet radiation. That hypothesis also requires additional research.

The third way this carbon was produced has possible biological roots.

If this kind of depleted carbon measurement was made on Earth, it would show that microbes were consuming biologically produced methane. While Curiosity has previously detected methane on Mars, researchers can only guess if there were once large plumes of methane being released from beneath the surface of Mars. If this was the case and there were microbes on the Martian surface, they would have consumed this methane.

It’s also possible that the methane interacted with ultraviolet light, leaving a trace of carbon on the Martian surface.

MORE DRILLING ON THE HORIZON

The Curiosity rover will be returning to the site where it collected the majority of the samples in about a month, which will allow for another chance to analyze sediment from this intriguing location.

“This research accomplished a long-standing goal for Mars exploration,” House said. “To measure different carbon isotopes — one of the most important geology tools — from sediment on another habitable world, and it does so by looking at nine years of exploration.”

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Mars Was Likely A Cold, Wet World 3 Billion Years Ago – IFLScience

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Mars is puzzling. From rover and satellite observations we know that it once had plenty of water on its surface, which usually suggests warm and wet conditions. On the other hand, evidence suggests the planet was always pretty chilly, even in the distant past, but it’s not a cold, dry desert either. These two ideas are often at odds, but new research suggests that they could both be true: ancient Mars was likely a frigid world both cold and wet.

Researchers set out to create a model that can explain the perplexing features witnessed on the Red Planet. If the planet wasn’t warm and wet or cold and dry could there be a third option? Publishing their findings in Proceedings of the National Academy of Sciences, they believe that their cold and wet scenario can explain the existence of a vast liquid ocean in the Northern Hemisphere of Mars, extending to its polar region.

However, the model needed to explain both the presence of a liquid ocean and ice-capped regions, like the presence of glacial valleys and ice sheets in the southern highlands.

Planetary scientists studying Mars have found evidence of ancient tsunamis that rocked the Red Planet. If the ocean was frozen due to a very cold climate, these tsunamis would not have happened. But a milder climate would have meant transferring water from the ocean to the land through precipitation. Cold and wet conditions, however, could have existed.

The team used an advanced general circulation model to work out the necessary parameters for this world. They calculated it was possible for an ocean to be stable even if the mean temperature of Mars was below 0°C (32°F), the freezing point of water, 3 billion years ago. They envisioned ice-covered plateaus in the south with glaciers flowing across the plains and returning to the ocean. Rainfall would have been moderate around the shoreline. In this scenario, the ocean surface could be up to 4.5°C (40°F); not tropical but enough for water to stay liquid.

The key to these conditions is all in the air. The atmosphere of Mars today is about 1 percent in density compared to Earth’s own. But, if in the past it was roughly the same and was made of about 10 percent hydrogen and the rest carbon dioxide, this scenario would actually work. Previous analyses have found strong evidence for a thicker atmosphere before it was ripped from the planet by the steady stream of particles from the Sun.

The model is certainly compelling in explaining the peculiarities of Mars, but of course, much more evidence is needed to understand what the Red Planet was really like billions of years ago.

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Explainer-Scientists struggle to monitor Tonga volcano after massive eruption

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Scientists are struggling to monitor an active volcano that erupted off the South Pacific island of Tonga at the weekend, after the explosion destroyed its sea-level crater and drowned its mass, obscuring it from satellites.

The eruption of Hunga-Tonga-Hunga-Ha’apai volcano, which sits on the seismically active Pacific Ring of Fire, sent tsunami waves across the Pacific Ocean and was heard some 2,300 kms (1,430 miles) away in New Zealand.

“The concern at the moment is how little information we have and that’s scary,” said Janine Krippner, a New Zealand-based volcanologist with the Smithsonian Global Volcanism Program.

“When the vent is below water, nothing can tell us what will happen next.”

Krippner said on-site instruments were likely destroyed in the eruption and the volcanology community was pooling together the best available data and expertise to review the explosion and predict anticipated future activity.

Saturday’s eruption was so powerful that space satellites captured not only huge clouds of ash but also an atmospheric shockwave that radiated out from the volcano at close to the speed of sound.

Photographs and videos showed grey ash clouds billowing over the South Pacific and metre-high waves surging onto the coast of Tonga.

There are no official reports of injuries or deaths in Tonga https://www.reuters.com/business/environment/impact-assessment-aid-efforts-underway-world-responds-tonga-tsunami-2022-01-16 yet but internet and telephone communications are extremely limited and outlying coastal areas remain cut off.

Experts said the volcano, which last erupted in 2014, had been puffing away for about a month before rising magma, superheated to around 1,000 degrees Celsius, met with 20-degree seawater on Saturday, causing an instantaneous and massive explosion.

The unusual “astounding” speed and force of the eruption indicated a greater force at play than simply magma meeting water, scientists said.

As the superheated magma rose quickly and met the cool seawater, so did a huge volume of volcanic gases, intensifying the explosion, said Raymond Cas, a professor of volcanology at Australia’s Monash University.

Some volcanologists are likening the eruption to the 1991 Pinatubo eruption in the Philippines, the second-largest volcanic eruption of the 20th century, which killed around 800 people.

The Tonga Geological Services agency, which was monitoring the volcano, was unreachable on Monday. Most communications to Tonga have been cut after the main undersea communications cable lost power.

LIGHTNING STRIKES

American meteorologist, Chris Vagasky, studied lightning around the volcano and found it increasing to about 30,000 strikes in the days leading up to the eruption. On the day of the eruption, he detected 400,000 lightning events in just three hours, which comes down to 100 lightning events per second.

That compared with 8,000 strikes per hour during the Anak Krakatau eruption in 2018, caused part of the crater to collapse into the Sunda Strait and send a tsunami crashing into western Java, which killed hundreds of people.

Cas said it is difficult to predict follow-up activity and that the volcano’s vents could continue to release gases and other material for weeks or months.

“It wouldn’t be unusual to get a few more eruptions, though maybe not as big as Saturday,” he said. “Once the volcano is de-gassed, it will settle down.”

 

(Reporting by Kanupriya Kapoor; Editing by Jane Wardell and Michael Perry)

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