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How much water is left for nature? The search for the appropriate environmental flow

ENVIRONMENT

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26/06/2025

How much water is left for nature? The search for the appropriate environmental flow

In many rivers, only a small amount of streamflow remains for nature after water is diverted for hydropower production. In light of climate change and biodiversity loss, this is having increasingly serious consequences. Researchers from WSL, UZH and Eawag have compiled an interdisciplinary overview and highlighted areas where knowledge gaps exist.

In many rivers, little streamflow remains because of anthropogenic water diversions for purposes such as energy production or agricultural irrigation. A legally required minimum flow, known as environmental flow, is intended to ensure the biological function of rivers. In the article “Restwasser. Die Suche nach der angemessenen Menge” (“Environmental flow. The search for the adequate amount,” German only) in the magazine Aqua & Gas, Tobias Wechsler from the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) describes why determining adequate environmental flows is so complex. “Environmental flow means a reduction in hydropower production, but a minimum subsistence level for aquatic ecology,” explains the hydrologist.

Since 1975, Switzerland’s constitution requires that “adequate environmental flows” be maintained after hydropower production. However, “when the environmental flow provisions were enshrined in the Water Protection Act in 1991, an approach prevailed that resulted in lower minimum environmental flows than recommended by ecological studies,” the authors write in their report.

Ecological relevance of environmental flow

Thirty years later, the ecology of our water bodies has not fared well. Aquatic organisms are overrepresented on Switzerland’s red lists of endangered species, with 65% of fish and cyclostomes and 47% of invertebrates listed. These groups provide a simplified way of assessing the ecological status of water bodies. Reduced water volumes can slow down streamflow velocity, promote algae growth, and cause greater fluctuations in water temperatures—conditions that are unsuitable for specialized species.

However, even organisms living in dry habitats in the riparian zone, such as on riverbanks, are affected, for example, species of dragonflies and shore plants, as well as birds such as the little ringed plover. “River organisms can cope with disturbances such as high or low water levels, but not with very small amounts of environmental flow or daily fluctuations, such as those caused by hydropower production,” says WSL ecologist Sabine Fink.

She is studying the ecological impacts of hydropeaking—the rapid fluctuations in streamflow caused by hydropower operations. Parts of the rivers almost dry up, while following sudden surges erode the stream bed and carve deep channels into it. Both have consequences for the organisms living in the riparian zones and on islands.

“In the Alpine rivers we have been observing over the last 10 years, that the species composition has changed and now corresponds to that found in classic dry habitats.”

It is becoming increasingly clear that climate change must also be taken into account. It affects stream flows and has a direct impact on water management, but also on biodiversity in rivers. At the same time, there is political will to expand hydropower generation.

“These changes raise the question of what constitutes an adequate amount of environmental flow,” emphasizes Wechsler. This is because the demands of nature and other water uses, such as for cooling water or irrigation, are also increasing.

“Environmental flow and streamflow fluctuations from individual power plants affect the survival of species and habitats in entire catchment areas,” says ecologist Fink, “which is why solutions are needed for entire river systems.”

Water rights should become more flexible

What could be the next steps? Wechsler sees these in particular in the design of water rights concessions. The right to use water, a public good, is currently granted for up to 80 years and allows little scope for adjustments during the term of the concession. “Adaptive management can help to respond better to changes such as climate change or hydropeaking—without losing planning security,” says Wechsler.

To better reconcile the various demands placed on rivers, transparent data is needed. Currently, there is no independent data on the impact of environmental flow requirements on hydropower production. However, “In the past, this influence has been overestimated,” write the authors of the study in Aqua & Gas. As scientists, ecologist Fink and hydrologist Wechsler aim to identify interrelationships and communicate them so that they can be incorporated into sustainable water resources management.

Limited flexibility in water concessions

For hydropower plants granted concessions before 1992, the environmental flow requirements (Art. 31–33 GSchG) only come into effect after new concessioning. This has led to long deadlines: as concessions were often granted for the maximum permissible period of 80 years, in some places almost a century can pass between the inclusion of adequate environmental flows in the constitution (1975), the entry into force of the water protection act “GSchG” (1992) and the actual implementation.

Provided by Swiss Federal Institute for Forest, Snow and Landscape Research

These Canadian rocks may be the oldest on Earth

PALEONTOLOGY

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26/06/2025

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These Canadian rocks may be the oldest on Earth

Scientists have identified what could be the oldest rocks on Earth from a rock formation in Canada.

The Nuvvuagittuq Greenstone Belt has long been known for its ancient rocks—plains of streaked gray stone on the eastern shore of Hudson Bay in Quebec. But researchers disagree on exactly how old they are.

Work from two decades ago suggested the rocks could be 4.3 billion years old, placing them in the earliest period of Earth’s history. But other scientists using a different dating method contested the finding, arguing that long-ago contaminants were skewing the rocks’ age and that they were actually slightly younger at 3.8 billion years old.

In the new study, researchers sampled a different section of rock from the belt and estimated its age using the previous two dating techniques—measuring how one radioactive element decays into another over time. The result: The rocks were about 4.16 billion years old.

The different methods “gave exactly the same age,” said study author Jonathan O’Neil with the University of Ottawa.

The new research was published Thursday in the journal Science.

Earth formed about 4.5 billion years ago from a collapsing cloud of dust and gas soon after the solar system existed. Primordial rocks often get melted and recycled by Earth’s moving tectonic plates, making them extremely rare on the surface today. Scientists have uncovered 4 billion-year-old rocks from another formation in Canada called the Acasta Gneiss Complex, but the Nuvvuagittuq rocks could be even older.

This photo provided by researcher Jonathan O’Neil shows the landscape at the Nuvvuagittuq Greenstone Belt in northeastern Canada. Credit: Jonathan O’Neil via AP
This photo provided by researcher Jonathan O’Neil shows the landscape at the Nuvvuagittuq Greenstone Belt in northeastern Canada. Credit: Jonathan O’Neil via AP
This photo provided by researcher Jonathan O’Neil shows the landscape at the Nuvvuagittuq Greenstone Belt in northeastern Canada. Credit: Jonathan O’Neil via AP
This photo provided by researcher Jonathan O’Neil shows the landscape at the Nuvvuagittuq Greenstone Belt in northeastern Canada. Credit: Jonathan O’Neil via AP

Studying rocks from Earth’s earliest history could give a glimpse into how the planet may have looked—how its roiling magma oceans gave way to tectonic plates—and even how life got started.

“To have a sample of what was going on on Earth way back then is really valuable,” said Mark Reagan with the University of Iowa, who studies volcanic rocks and lava and was not involved with the new study.

The rock formation is on tribal Inukjuak lands and the local Inuit community has temporarily restricted scientists from taking samples from the site due to damage from previous visits.

This photo provided by researcher Jonathan O’Neil shows a closeup of a rock from Canada’s Nuvvuagittuq Greenstone Belt dated to about 4.16 billion years old. Credit: Jonathan O’Neil via AP
This photo provided by researcher Jonathan O’Neil shows an outcropping of about 4.16 billion year old rocks at the Nuvvuagittuq Greenstone Belt in northeastern Canada, with a knife to indicate scale. Credit: Jonathan O’Neil via AP
This photo provided by researcher Jonathan O’Neil shows a closeup of a rock from Canada’s Nuvvuagittuq Greenstone Belt dated to about 4.16 billion years old. Credit: Jonathan O’Neil via AP
This photo provided by researcher Jonathan O’Neil shows an outcropping of about 4.16 billion year old rocks at the Nuvvuagittuq Greenstone Belt in northeastern Canada, with a knife to indicate scale. Credit: Jonathan O’Neil via AP

After some geologists visited the site, large chunks of rock were missing and the community noticed pieces for sale online, said Tommy Palliser, who manages the land with the Pituvik Landholding Corp. The Inuit community wants to work with scientists to set up a provincial park that would protect the land while allowing researchers to study it.

“There’s a lot of interest for these rocks, which we understand,” said Palliser, a member of the community. “We just don’t want any more damage.”

More information: C. Sole et al, Evidence for Hadean mafic intrusions in the Nuvvuagittuq Greenstone Belt, Canada, Science (2025). DOI: 10.1126/science.ads8461. www.science.org/doi/10.1126/science.ads8461

Journal information: Science

A new look at Colorado’s Dinosaur Ridge reveals what may be the largest known dinosaur mating dance arena

PALEONTOLOGY

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25/06/2025

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A new look at Colorado’s Dinosaur Ridge reveals what may be the largest known dinosaur mating dance arena

A team of paleontologists and researchers affiliated with several institutions in the U.S. has discovered what may be the largest known dinosaur mating dance arena ever found. For their study, published in the journal Cretaceous Research, the group used drone imagery to gain a new perspective on Colorado’s famous Dinosaur Ridge.

Dinosaur Ridge has been yielding dinosaur bones since the late 1800s. For this study, the research team got a new look at a part of the area at the base of the ridge that was once a tidal flat—one that was flooded periodically. Prior research had shown that there were a few dinosaur “lekking” spots, or leks, in the area.

Such spots, the researchers note, are similar to those still used by birds. They are places where males perform dances for females in hopes of winning a mate and in so doing tend to leave behind telltale footprints or scrape marks. To gain a better perspective, the researchers studied drone imagery of the area captured by the U.S. Geological Survey in 2019 and again in 2024.

Scientists find what may be the largest known dinosaur mating dance arena — Bedding plane surfaces at Dinosaur Ridge. (A) Main track site denoted by red arrow, surface 2b and 2h denoted by yellow arrows. (B–C) Orthomosaic and DSM of surface 2b with (D) radially arranged root traces preserved on the surface. (E) Field photograph of surface. Credit: *Cretaceous Research* (2025). DOI: 10.1016/j.cretres.2025.106176

In studying the images, the researchers found evidence of multiple dinosaur lekking spots, suggesting the whole site was once a single large lekking spot. The images also allowed the researchers to get a better view of the spots themselves—people, including scientists, are banned from walking in the area, lest they destroy historical evidence.

In their study, the research team found evidence of two distinct types of marks—bowl-like and long and thin. Such differences could speak to various behaviors, such as display and nest building. They also noted that prior digging at some of the dancing spots had revealed marks in different strata, suggesting a given site was used by different dinosaurs at different times. Different marks, they noted, also showed different dancing styles, such as dragging a claw.

The team also compared the lekking spots with others that have been identified in other sites in Colorado and Alberta, Canada, and found them to look much the same, adding more evidence of Colorado Ridge as the site of the largest dinosaur lek found to date.

Written for you by our author Bob Yirka, edited by Lisa Lock , and fact-checked and reviewed by Robert Egan —this article is the result of careful human work. We rely on readers like you to keep independent science journalism alive. If this reporting matters to you, please consider a donation (especially monthly). You’ll get an ad-free account as a thank-you.

More information: Rogers C.C. Buntin et al, A new theropod dinosaur lek in the Cretaceous Dakota Sandstone (Dinosaur Ridge, Colorado, USA), Cretaceous Research (2025). DOI: 10.1016/j.cretres.2025.106176

Journal information: Cretaceous Research

New species of ‘mystery’ dinosaur unveiled at the Natural History Museum

PALEONTOLOGY

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25/06/2025

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New species of ‘mystery’ dinosaur unveiled at the Natural History Museum

A small dinosaur that once dashed along North American riverbanks has found a new home in London. The new species, named Enigmacursor mollyborthwickae, is the most complete named specimen of its kind and is now on permanent display at the Natural History Museum.

The new dinosaur has emerged from a “taxonomic tangle” more than a century in the making.

The U.S.’s Morrison Formation has produced some of the most famous dinosaurs in the world, such as Allosaurus and Stegosaurus. But not all of its species are as well known, with many smaller herbivorous dinosaurs having been historically overlooked.

Now, researchers have named a new species of these little herbivores, calling it Enigmacursor mollyborthwickae. They hope that this work will shine some light on long-ignored animals of the formation and clear the way for more discoveries in the future.

Professor Susannah Maidment is one of our dinosaur experts and co-lead author of the research into Enigmacursor. She says that the new species could be the first of many small dinosaurs to be found from the western U.S.

“While the Morrison Formation has been well-known for a long time, most of the focus has been on searching for the biggest and most impressive dinosaurs,” Susannah says. “Smaller dinosaurs are often left behind, meaning there are probably many still in the ground.”

“Enigmacursor shows that there’s still plenty to discover in even this well-studied region, and highlights just how important it is to not take historical assumptions about dinosaurs at face value.”

The paper was published in the journal Royal Society Open Science, and visitors can now see the new dinosaur on show in our Earth Hall.

What was Enigmacursor like?

The story of Enigmacursor begins during the closing years of the Late Jurassic between 150 and 145 million years ago. At the time, the Morrison Formation would have been a vast network of rivers and floodplains stretching across large parts of the western United States.

Huge, long-necked herbivores like Diplodocus would have roamed the landscape, while carnivorous theropods like Ceratosaurus would have stalked the riverside. Trying to keep out of their way would have been a variety of smaller dinosaurs, including Enigmacursor.

Its long legs would have allowed this small herbivore to dart away from danger, keeping it one step ahead of its predators, and this speedy lifestyle inspired the dinosaur’s name. Enigmacursor means “mysterious runner,” while the species name honors Molly Borthwick, whose generous donation allowed for the purchase and display of the dinosaur.

The dinosaur was only around one meter long, but there are signs that the dinosaur was not fully grown, says co-lead author Professor Paul Barrett.

“One feature we look at in dinosaurs are the neural arches,” Paul explains. “These are the top section of vertebrae, and form separately from the lower parts. They gradually merge as an animal gets older, so by examining them you can see whether it was still growing.”

“We can speculate that Enigmacursor probably wasn’t that old, as it doesn’t seem to have many of its neural arches fused in place. However, the way the fossil was prepared before it was acquired by the Natural History Museum has obscured some of these details, so we can’t be certain.”

It’s also unclear exactly how the animal died, as there are no obvious signs of injury or illness in the bones. In any case, the remains of Enigmacursor ended up buried within the Morrison Formation, waiting to be found millions of years later.

From Nanosaurus to Enigmacursor

The new fossils were unearthed on private land between 2021 and 2022, and put up for sale through a commercial fossil dealer. They were initially advertised as being from an animal called Nanosaurus, a poorly known species of dinosaur first named in the 1870s.

It was then brought it to the attention of Susannah and Paul, who were interested in finding out more about this enigmatic animal. After the fossils were purchased by the Natural History Museum, the paleontologists began digging into Nanosaurus’s past, and were shocked by what they found.

“Nanosaurus wasn’t named based on many fossilized bones, but largely the preserved impressions of bones pressed into hardened sand that are very difficult to study,” Paul says. “So, we turned to the other bones that have been referred to the group over the past century, but these weren’t particularly well-preserved either.”

“It just goes to show how much paleontology has changed in the past 150 years,” Susannah adds. “When Nanosaurus was named in 1877, there weren’t that many named dinosaurs, so the few characteristics that its fossils preserved would have been unique.”

“Now, however, we have found hundreds of small dinosaurs from all over the world and know that the fossils of Nanosaurus just aren’t that useful, let alone enough to name a species with. As a result, it made sense to put them to one side and name Enigmacursor as a new species instead.”

“While Nanosaurus is no longer considered a species,” some of its fossils still have scientific value. The few features that can be identified in the various fossils show that they’re different to Enigmacursor. This suggests that further small dinosaur species could be discovered from the Morrison.

Some of these fossils may have already been uncovered. Susannah and Paul are aware of several well-preserved skeletons held in museums around the world that haven’t yet been formally named, and might represent these missing dinosaurs.

The researchers hope to study some of these fossils in the future, and help to further clear up the muddled history of these dinosaurs.

“Taxonomic work is generally overlooked and not treated as a particularly important or employable skill,” Susannah adds. “However, it’s the foundation that all paleontology is built on. If it’s wrong, then everything else collapses.”

“We need more funding and support to ensure that this vital work doesn’t stop, so that we can better understand how life on Earth evolved.”

More information: Susannah C. R. Maidment et al, Enigmacursor mollyborthwickae , a neornithischian dinosaur from the Upper Jurassic Morrison Formation of the western USA, Royal Society Open Science (2025). DOI: 10.1098/rsos.242195

Journal information: Royal Society Open Science

Provided by Natural History Museum

This story is republished courtesy of Natural History Museum. Read the original story here.

A chance discovery of a 350 million-year-old fossil reveals a new type of ray-finned fish

PALEONTOLOGY

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25/06/2025

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A chance discovery of a 350 million-year-old fossil reveals a new type of ray-finned fish

In 2015, two members of the Blue Beach Fossil Museum in Nova Scotia found a long, curved fossil jaw, bristling with teeth. Sonja Wood, the museum’s owner, and Chris Mansky, the museum’s curator, found the fossil in a creek after Wood had a hunch.

The fossil they found belonged to a fish that had died 350 million years ago, its bony husk spanning nearly a meter on the lake bed. The large fish had lived in waters thick with rival fish, including giants several times its size. It had hooked teeth at the tip of its long jaw that it would use to trap elusive prey and fangs at the back to pierce it and break it down to eat.

For the last eight years, I have been part of a team under the lead of paleontologist Jason Anderson, who has spent decades researching the Blue Beach area of Nova Scotia, northwest of Halifax, in collaboration with Mansky and other colleagues. Much of this work has been on the tetrapods—the group that includes the first vertebrates to move to land and all their descendants—but my research focuses on what Blue Beach fossils can tell us about how the modern vertebrate world formed.

Birth of the modern vertebrate world

The modern vertebrate world is defined by the dominance of three groups: the cartilaginous fishes or chondrichthyans (including sharks, rays and chimeras), the lobe-finned fishes or sarcopterygians (including tetrapods and rare lungfishes and coelacanths), and the ray-finned fishes or actinopterygians (including everything from sturgeon to tuna). Only a few jawless fishes round out the picture.

This basic grouping has remained remarkably consistent—at least for the last 350 million years.

Before then, the vertebrate world was a lot more crowded. In the ancient vertebrate world, during the Silurian Period (443.7–419.2 MA) for example, the ancestors of modern vertebrates swam alongside spiny pseudo-sharks (acanthodians), fishy sarcopterygians, placoderms and jawless fishes with bony shells.

Armored jawless fishes had dwindled by the Late Devonian Period (419.2–358.9 MA), but the rest were still diverse. Actinopterygians were still restricted to a few species with similar body shapes.

By the immediately succeeding early Carboniferous times, everything had changed. The placoderms were gone, the number of species of fishy sarcopterygians and acanthodians had cratered, and actinopterygians and chondrichthyans were flourishing in their place.

The modern vertebrate world was born.

A sea change

Blue Beach has helped build our understanding of how this happened. Studies describing its tetrapods and actinopterygians have showed the persistence of Devonian-style forms in the Carboniferous Period.

Whereas the abrupt end-Devonian decline of the placoderms, acanthodians and fishy sarcopterygians can be explained by a mass extinction, it now appears that multiple types of actinopterygians and tetrapods survived to be preserved at Blue Beach. This makes a big difference to the overall story: Devonian-style tetrapods and actinopterygians survived and contributed to the evolution of these groups into the Carboniferous Period.

But significant questions remain for paleontologists. One point of debate revolves around how actinopterygians diversified as the modern vertebrate world was born—whether they explored new ways of feeding or swimming first.

The Blue Beach fossil was actinopterygian, and we wondered what it could tell us about this issue. Comparison was difficult. Two actinopterygians with long jaws and large fangs were known from the preceding Devonian Period (Austelliscus ferox and Tegeolepis clarki), but the newly found jaw had more extreme curvature and the arrangement of its teeth. Its largest fangs are at the back of its jaw, but the largest fangs of Austelliscus and Tegeolepis are at the front.

These differences were significant enough that we created a new genus and species: Sphyragnathus tyche. And, in view of the debate on actinopterygian diversification, we made a prediction: that the differences in anatomy between Sphyragnathus and Devonian actinopterygians represented different adaptations for feeding.

Front fangs

To test this prediction, we compared Sphyragnathus, Austelliscus and Tegeolepis to living actinopterygians. In modern actinopterygians, the difference in anatomy reflects a difference in function: front-fangs capture prey with their front teeth and grip it with their back teeth, but back-fangs use their back teeth.

Since we couldn’t observe the fossil fish in action, we analyzed the stress their teeth would experience if we applied force. The back teeth of Sphyragnathus handled force with low stress, making them suited for a role in piercing prey, but the back teeth of Austelliscus and Tegeolepis turned low forces into significantly higher stress, making them best suited for gripping.

We concluded that Sphyragnathus was the earliest actinopterygian adapted for breaking down prey by piercing, which also matches the broader predictions of the feeding-first hypothesis.

Substantial work remains—only the jaw of Sphyragnathus is preserved, so the “locomotion-first” hypothesis was untested. But this represents the challenge and promise of paleontology: get enough tantalizing glimpses into the past and you can begin to unfold a history.

As for the actinopterygians, current research indicates that they first diversified in the Devonian Period and shifted into new roles when the modern vertebrate world was born.

Provided by The Conversation

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Gone with the glaciers: Researchers track unprecedented ice loss

OCEANOGRAPHY

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25/06/2025

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Gone with the glaciers: Researchers track unprecedented ice loss

A study published in Geophysical Research Letters reveals that glaciers in western Canada, the United States, and Switzerland lost around 12% of their ice between 2001 and 2024.

A 2021 study in Nature showed that glacial melt doubled between 2010 and 2019 compared with the first decade of the twenty-first century. This new paper builds on that research, says lead author Brian Menounos, and shows that in the years since, glacial melt continued at an alarming pace.

“Over the last four years, glaciers lost twice as much ice compared to the previous decade,” says Menounos, a professor at the University of Northern British Columbia and a chief scientist at the Hakai Institute. “Glacial melt is just falling off a cliff.”

Warm, dry conditions were a major cause of loss across the study areas, as were impurities from the environment that led to glacial darkening and accelerated melt. In Switzerland, the main cause of darkening was dust blown north from the Sahara Desert; in North America, it was ash, or black carbon, from wildfires.

The research combined extensive aerial surveys with ground-based observations of three glaciers in western Canada, four glaciers in the US Pacific Northwest, and 20 glaciers in Switzerland, all of which are important for culture, tourism, and cool fresh water—and all of which are melting rapidly.

Snow and ice, when not obscured by dark particles, reflect back energy from the sun in a process known as the albedo effect. To dig deeper into the North American story, Menounos and his collaborators used satellite imagery and reanalysis data to look at declines in albedo. They found that albedo dropped in 2021, 2023, and 2024, but the biggest declines occurred in 2023—the worst wildfire season in Canadian history.

“2023 was the year of record, no question,” Menounos says.

In contrast to reflective white snow, a glacier covered in black carbon will absorb more radiation from the sun. This heats up glaciers and accelerates melting.

At Haig Glacier in Canada’s Rocky Mountains, glacial darkening was responsible for nearly 40% of the melting between 2022 and 2023, the researchers found. Yet despite such evidence, physical processes like the albedo effect aren’t currently incorporated into climate predictions for glacier loss, so these masses of ice could be melting faster than we realize.

“If we’re thinking, well, we have 50 years before the glaciers are gone, it could actually be 30,” Menounos says. “So we really need better models going forward.”

In the areas covered by this study, the impact of glacier loss on sea level rise is small, but a longer-term decline in glacial runoff could impact human and aquatic ecosystems, especially in times of drought, Menounos adds.

In the shorter term, increased melting raises the risk of geohazards like outburst floods from newly formed glacier lakes. All of this poses questions around how communities should respond as well as plan for a future with less ice.

“Society needs to be asking what are the implications of ice loss going forward,” Menounos says. “We need to start preparing for a time when glaciers are gone from western Canada and the United States.”

More information: Glaciers in Western Canada‐Conterminous US and Switzerland Experience Unprecedented Mass Loss Over the Last Four Years (2021–2024), Geophysical Research Letters (2025). DOI: 10.1029/2025GL115235

Journal information: Geophysical Research Letters , Nature

Provided by Hakai Institute

Scientists detect deep Earth pulses beneath Africa

EARTH

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25/06/2025

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Scientists detect deep Earth pulses beneath Africa

Research led by Earth scientists at the University of Southampton has uncovered evidence of rhythmic surges of molten mantle rock rising from deep within the Earth beneath Africa. These pulses are gradually tearing the continent apart and forming a new ocean.

The findings, published in Nature Geoscience, reveal that the Afar region in Ethiopia is underlain by a plume of hot mantle that pulses upward like a beating heart.

The team’s discovery reveals how the upward flow of hot material from the deep mantle is strongly influenced by the tectonic plates—the massive solid slabs of Earth’s crust—that ride above it.

Over millions of years, as tectonic plates are pulled apart at rift zones like Afar, they stretch and thin—almost like soft plasticine—until they rupture. This rupturing marks the birth of a new ocean basin.

Lead author Dr. Emma Watts, who conducted the research at the University of Southampton and is now based at Swansea University, said, “We found that the mantle beneath Afar is not uniform or stationary—it pulses, and these pulses carry distinct chemical signatures. These ascending pulses of partially molten mantle are channeled by the rifting plates above. That’s important for how we think about the interaction between Earth’s interior and its surface.”

The project involved experts from 10 institutions, including the University of Southampton, Swansea University, Lancaster University, the Universities of Florence and Pisa, GEOMAR in Germany, the Dublin Institute for Advanced Studies, Addis Ababa University, and the GFZ German Research Center for Geosciences.

A window into Earth’s interior

The Afar region is a rare place on Earth where three tectonic rifts converge: the Main Ethiopian Rift, the Red Sea Rift, and the Gulf of Aden Rift.

Geologists have long suspected that a hot upwelling of the mantle, sometimes referred to as a plume, lies beneath the region, helping to drive the extension of the crust and the birth of a future ocean basin. But until now, little was known about the structure of this upwelling, or how it behaves beneath rifting plates.

The team collected more than 130 volcanic rock samples from across the Afar region and the Main Ethiopian Rift.

They used these, plus existing data and advanced statistical modeling, to investigate the structure of the crust and mantle, as well as the melts that it contains.

Their results show that underneath the Afar region is a single, asymmetric plume, with distinct chemical bands that repeat across the rift system, like geological barcodes. These patterns vary in spacing depending on the tectonic conditions in each rift arm.

Tom Gernon, Professor of Earth Science at the University of Southampton and co-author of the study, said, “The chemical striping suggests the plume is pulsing, like a heartbeat. These pulses appear to behave differently depending on the thickness of the plate, and how fast it’s pulling apart. In faster-spreading rifts like the Red Sea, the pulses travel more efficiently and regularly like a pulse through a narrow artery.”

A succession of volcanic deposits at Boset Volcano in the Main Ethiopian Rift. Credit: Prof Thomas Gernon, University of Southampton
Active lava flows spilling out of the Erta Ale volcano in Afar, Ethiopia. Credit: Dr. Derek Keir, University of Southampton/ University of Florence
Professor Tom Gernon sampling volcanic deposits at Boset Volcano in the Main Ethiopian Rift. Credit: Prof Thomas Gernon, University of Southampton
Looking out into the Main Ethiopian Rift, taken at Boset Volcano in Ethiopia. Credit: Prof Thomas Gernon, University of Southampton
Fresh basaltic lava flows in the region of Afar, Ethiopia. Credit: Dr. Derek Keir, University of Southampton/ University of Florence
A succession of volcanic deposits at Boset Volcano in the Main Ethiopian Rift. Credit: Prof Thomas Gernon, University of Southampton
Active lava flows spilling out of the Erta Ale volcano in Afar, Ethiopia. Credit: Dr. Derek Keir, University of Southampton/ University of Florence

Links to volcanism and earthquakes

This new research shows that the mantle plume beneath the Afar region is not static, but dynamic and responsive to the tectonic plate above it.

Dr. Derek Keir, Associate Professor of Earth Science at the University of Southampton and the University of Florence, and co-author of the study, said, “We have found that the evolution of deep mantle upwellings is intimately tied to the motion of the plates above. This has profound implications for how we interpret surface volcanism, earthquake activity, and the process of continental breakup.”

“The work shows that deep mantle upwellings can flow beneath the base of tectonic plates and help to focus volcanic activity to where the tectonic plate is thinnest. Follow-on research includes understanding how and at what rate mantle flow occurs beneath plates,” added Keir.

Dr. Watts added, “Working with researchers with different expertise across institutions, as we did for this project, is essential to unraveling the processes that happen under Earth’s surface and relate it to recent volcanism. Without using a variety of techniques, it is hard to see the full picture, like putting a puzzle together when you don’t have all the pieces.”

More information: Mantle upwelling at Afar triple junction shaped by overriding plate dynamics, Nature Geoscience (2025). DOI: 10.1038/s41561-025-01717-0

Journal information: Nature Geoscience

Provided by University of Southampton

Unexpected mineral in a Ryugu grain challenges paradigm of the nature of primitive asteroids

ASTRONOMY

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23/06/2025

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Unexpected mineral in a Ryugu grain challenges paradigm of the nature of primitive asteroids

The pristine samples from asteroid Ryugu returned by the Hayabusa2 mission on December 6, 2020, have been vital to improving the understanding of primitive asteroids and the formation of the solar system. The C-type asteroid Ryugu is composed of rocks similar to meteorites called CI chondrites, which contain relatively high amounts of carbon, and have undergone extensive aqueous alteration in their past.

A research team at Hiroshima University discovered the presence of the mineral djerfisherite, a potassium-containing iron-nickel sulfide, in a Ryugu grain. The presence of this mineral is wholly unexpected, as djerfisherite does not form under the conditions Ryugu is believed to have been exposed to over its existence.

The findings are published in the journal Meteoritics & Planetary Science.

“Djerfisherite is a mineral that typically forms in very reduced environments, like those found in enstatite chondrites, and has never been reported in CI chondrites or other Ryugu grains,” says first and corresponding author Masaaki Miyahara, associate professor at the Graduate School of Advanced Science and Engineering, Hiroshima University.

“Its occurrence is like finding a tropical seed in Arctic ice—indicating either an unexpected local environment or long-distance transport in the early solar system.”

Miyahara’s team had been carrying out experiments to understand the effects of terrestrial weathering on Ryugu grains. While observing the grains by field-emission transmission electron microscopy (FE-TEM) for effects of weathering, they found djerfisherite in the number 15 grain of sample plate C0105-042.

An unexpected mineral in a Ryugu grain — Bright-field transmission electron micrograph of the djerfisherite inclusion in the number 15 grain of sample plate C0105-042 from Ryugu. Credit: Hiroshima University/Masaaki Miyahara

“The discovery of djerfisherite in a Ryugu grain suggests that materials with very different formation histories may have mixed early in the solar system’s evolution, or that Ryugu experienced localized, chemically heterogeneous conditions not previously recognized. This finding challenges the notion that Ryugu is compositionally uniform and opens new questions about the complexity of primitive asteroids,” Miyahara elaborates.

Ryugu is a part of a larger parent body that formed between 1.8 to 2.9 million years after the beginning of the solar system. This parent body is thought to have originated in the outer region of the solar system, where water and carbon dioxide existed in the form of ice.

Inside the parent body, heat generated by the decay of radioactive elements caused the ice to melt around 3 million years after its formation. The temperature during this process is estimated to have remained below approximately 50°C.

In contrast, the parent bodies of enstatite chondrites, which are known to contain djerfisherite, are believed to have formed in the inner region of the solar system. Thermodynamic calculations indicate that djerfisherite in enstatite chondrites formed directly from high-temperature gas.

In addition, hydrothermal synthesis experiments have shown that djerfisherite can also form through reactions between potassium-bearing fluids and Fe-Ni sulfides at temperatures above 350°C.

This led the team to propose two hypotheses for its presence in the Ryugu grain: either it arrived from another source during the formation of Ryugu’s parent body; or, it was formed intrinsically when the temperature of Ryugu was raised to above 350°C.

Preliminary evidence indicates that the intrinsic formation hypothesis is more likely to be true. The next steps will be to conduct isotopic studies of this and other Ryugu grains, to determine their origins.

“Ultimately, our goal is to reconstruct the early mixing processes and thermal histories that shaped small bodies like Ryugu, thereby improving our understanding of planetary formation and material transport in the early solar system,” Miyahara concludes.

More information: Masaaki Miyahara et al, Djerfisherite in a Ryugu grain: A clue to localized heterogeneous conditions or material mixing in the early solar system, Meteoritics & Planetary Science (2025). DOI: 10.1111/maps.14370

Provided by Hiroshima University

Meteorite-common amino acid induces formation of nanocavities in clay mineral, hinting at life’s origins

ASTRONOMY

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23/06/2025

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Meteorite-common amino acid induces formation of nanocavities in clay mineral, hinting at life’s origins

Researchers at the universities of Amsterdam and Utrecht have observed the formation of nanocavities in montmorillonite clay under exposure to gamma-aminobutyric acid, a molecule commonly found on meteorites. This hitherto unrecognized phenomenon could be relevant to the origin of life on Earth, by introducing 3D confined nano-environments in clay that might have facilitated life’s first chemistry. The findings have been reported in Communications Earth & Environment.

The research, carried out as a part of the Planetary and ExoPlanetary Science Program (PEPSci) of the Dutch Research Council NWO, adds a novel dimension to the concept of the “warm little pond.” This primordial pond would have enabled the interaction of organics and minerals in a shallow water environment.

The catalytic action of the minerals could thereby have led to the creation of the first molecules of life from simpler organic building blocks. Much research has been carried out into the interaction of clay minerals with organic molecules, especially those that could lead to the formation of Earth-like bio-polymers such as proteins and RNA.

The prebiotic molecular inventory, however, is expected to be diverse, also including molecules that were introduced to Earth’s atmosphere through meteorites. In a novel approach, Ph.D. candidate Orr Rose Bezaly and her supervisors Helen King (Utrecht University) and Annemieke Petrignani (University of Amsterdam) have now focused on the role of gamma-aminobutyric acid (GABA), a small molecule commonly found on meteorites. It has no known role in protein synthesis and has only a weak interaction with clays.

According to Petrignani it thus is a rather “unusual suspect” regarding the origin of life. “However, because of its widespread occurrence on meteorites, we thought it would be interesting to investigate its potential role. The results really surprised us.”

Partial exfoliation leading to nanocavities

In laboratory experiments, the researchers exposed the common clay montmorillonite (a layered aluminosilicate mineral) to a range of GABA concentrations. Using infrared spectroscopy, X-ray crystallography and transmission electron microscopy, they were able to reveal that the weak interaction of GABA with the clay induce a process of partial exfoliation, where clay layers are “peeled away.” The process, that initiates in the mid-layers of the clay, is also correlated with the formation of nanoscale cavities in between clay layers.

According to Petrignani, exfoliation is widely investigated, especially in materials science, but this atypical partial exfoliation has not been addressed and is also new in the field of origin of life. “We are the first to report on this, and we think it can be quite relevant. The nanoscale cavities we observe could facilitate the compartmentalization that is a fundamental requirement of a prebiotic system.”

Orr Rose Bezaly explains that such nanocompartments can foster a local disequilibrium within the larger scale prebiotic chemical environment, driving the synthesis of crucial molecules. “In the prebiotic context, this is most relevant to chemistry that requires low water activity, such as polymerization. This should somehow be coupled with compartmentalization—another critical function of life.

“Our discovery thus points us towards a feasible research route aimed at understanding nanoscale processes leading to the emergence of life. Beyond this field, the exfoliation method described in our work may be used as a sustainable technique for clay treatment for manipulation and synthesis of new materials.”

More information: Orr Rose Bezaly et al, Meteorite-common amino acid induces clay exfoliation and abiotic compartment formation, Communications Earth & Environment (2025). DOI: 10.1038/s43247-025-02417-8

Journal information: Communications Earth & Environment

Provided by University of Amsterdam

Big possum that lived 60 million years ago unearthed in Texas

PALEONTOLOGY

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23/06/2025

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Big possum that lived 60 million years ago unearthed in Texas

They say everything’s bigger in Texas. And that appears to be true, at least in the case of a group of ancient near-marsupials scientists call Swaindelphys.

Paleontologists from the University of Kansas have described for the first time a species of Swaindelphys discovered in Texas’ Big Bend National Park, though the ecosystem was drastically different in the Paleocene, when it thrived, than today.

Dubbed Swaindelphys solastella, the new species is much larger than similar species of Swaindelphys known from that period.

Their report detailing the ancient species, which was gigantic by the standards of Swaindelphys but still about the size of a modern hedgehog, appears in the Journal of Vertebrate Paleontology.

Lead author Kristen Miller, doctoral student at KU’s Biodiversity Institute and Natural History Museum, spent a year examining specimens collected decades ago in West Texas by the late Judith Schiebout, a paleontologist whose career was spent at Louisiana State University.

Some of the fossils collected at Big Bend by teams led by Schiebout had never been thoroughly studied, including molars that piqued Miller’s interest. She wanted to find out what kind of metatherians—the group that includes living marsupials and their extinct relatives—the Texas fossils represented.

“I compared them to a lot of other marsupials from around the same time period to see what they’re most closely related to,” Miller said. “It was a lot of morphological comparisons.”

The researchers initially thought the fossils were either survivors of a group of large Cretaceous metatherians that somehow made it through the Cretaceous-Paleogene extinction event or that they were the oldest member of a group of Eocene metatherians that showed up a few million years later.

Miller’s analysis eventually showed that both ideas were wrong. The Texas specimens belong to a surprisingly large species of Swaindelphys.

“Not only are they the largest metatherians from this time period, but they’re also the youngest and located at the most southern latitude,” Miller said.

Miller’s doctoral advisor and co-author, Chris Beard, senior curator with KU’s Biodiversity Institute and Foundation Distinguished Professor, said the first fossil mammals of the Paleocene age in Big Bend were first described decades ago.

“But our work is aimed at uncovering some of the smaller and harder-to-find fossil mammals that lived in Big Bend at that time,” Beard said. “The new fossil we’re describing is notable because it’s the largest marsupial—in terms of body size—found so far in the North American Paleocene.

“Since everything is bigger in Texas, this is perhaps not surprising.”

The KU researchers said their study of Swaindelphys potentially informs scientific study of early primates that inhabited the same ecosystems in Texas. Indeed, because Swaindelphys was in so many ways like early primates, their behavior and ancient distribution is seen by paleontologists as a collateral way to understand primate history.

For this reason, the research into Swaindelphys solastella—including analysis of specimens from the LSU and University of Texas at Austin collections—and new fieldwork in Big Bend National Park was supported by The Leakey Foundation, a donor-supported nonprofit organization with a mission “to uncover the story of human evolution and share this knowledge with the world.”

Along these lines, the KU researchers said the distribution patterns of Swaindelphys could indicate what kinds of natural features and barriers constrained the geographical spread of species in this time period, including early primates.

“It’s during the Paleocene, so it would have been warmer than it is now—probably more on the tropical side,” Miller said. “In place of desert terrain seen today, there was a lot more vegetation and probably lots of rivers and streams. We find these fossils in what we call fluvial deposits— so, deposits from ancient river systems.”

The investigators are interested in the differences in the kinds of fossil species found in more northern zones—like Wyoming and Alberta, Canada—compared to southern areas like the U.S.-Mexico border in the vicinity of Big Bend National Park.

“What’s interesting about the localities in Texas is we have some taxa we’d call ‘anachronistic’—things we don’t expect to see in Texas during the time these fossils were deposited,” Miller said. “The fossil record in places like the Bighorn Basin in Wyoming is very complete. It’s a really nice stratigraphic sequence spanning millions of years, so it’s easy in the Bighorn Basin to compare fossils from different localities.

“We call it biostratigraphy—you basically use the fossils to understand what time period you’re in. If you have certain taxa, you know it has to be from a specific time period.”

But outside of the Bighorn Basin, the picture gets murkier, according to the KU paleontologists. They said it’s harder to pinpoint the time periods associated with fossils. Miller and Beard wondered if some kind of geographic barrier was behind the difference.

Working with colleagues from KU’s Department of Geology, they’ve identified “an ancient high point or divide in the landscape, in southern Wyoming, that seems to correspond with the shift we see,” Miller said.

“North of that ancient divide, we see the classic Bighorn Basin taxa in their expected time periods,” she said. “But south of that, in river drainages that originate in the central Rockies and areas farther to the south, things start to go a little wacky. What we’re proposing is that this shift in river drainages marked the boundaries where ancient species of marsupials and primates lived.”

Miller and Beard think ancient landscapes posed obstacles to species distribution during the Paleocene—some taxa couldn’t cross rivers and high points, while others could. Miller plans to investigate the question with follow-up research.

“That’s our working hypothesis, and it’s something I’ll be looking into later in my dissertation,” she said. “We want to see if we can nail down, quantitatively, whether there’s a significant difference on either side of that potential barrier.”

More information: Kristen Miller et al, Biogeographic and biostratigraphic implications of a new species of Swaindelphys (Mammalia, Metatheria) from the Paleocene (Tiffanian) Black Peaks Formation, Big Bend National Park, Texas, Journal of Vertebrate Paleontology (2025). DOI: 10.1080/02724634.2025.2500501

Journal information: Journal of Vertebrate Paleontology

Provided by University of Kansas