Amphibious seals are less susceptible to hearing loss from airborne noises than their relatives and some can learn to close their ears for protection.
Seals are exposed to a variety of human noises in coastal environments, from underwater noises due to shipping, dredging, and sonars, to airborne noises like cars and planes. It is important to study the impact of these sounds on the animals’ hearing.
Reichmuth et al. analyzed a historical dataset from the University of California Santa Cruz to determine the onset of temporary threshold shift (TTS) in seals, which is the temporary decrease in hearing from loud noises.
“Our team worked together over several years to complete and publish this study, the results of which are still very relevant today,” said author Colleen Reichmuth.
To perform the experiments, the team trained a northern elephant seal and a harbor seal to voluntarily leave their pools and enter a hearing chamber to perform listening experiments. They first determined the hearing sensitivity of the two seals in a controlled, quiet environment, and then after exposure to noise of fixed bandwidth, level, and duration, they retested the seals so the researchers could measure any hearing changes.
They found that compared to related species — sea lions and fur seals — seals appear to be less susceptible to hearing loss from airborne noise. By providing missing data for amphibious seals, “these results can be used to refine noise exposure criteria for marine mammals,” Reichmuth said.
They also found that the duration of the noise was more impactful to changes in TTS than noise level.
Surprisingly, the team observed that one harbor seal experienced a change in noise sensitivity over the course of the experiment, as it learned to close its ears to protect itself from the noise, “an intriguing possibility that merits further study,” Reichmuth said.
Source: “Temporary threshold shifts from mid-frequency airborne noise exposures in seals,” by Colleen Reichmuth, Jillian M. Sills, Jason Mulsow, Marla M. Holt, and Brandon L. Southall, Journal of the Acoustical Society of America (2025). The article can be accessed at https://doi.org/10.1121/10.0036849.
We’ve sent some pretty interesting payloads to space since the first satellite (Sputnik 1) launched on October 4th, 1957. As access to space has increased, thanks largely to the commercial space industry, so too have the types of payloads we are sending.
Consider the Nyx capsule created by German aerospace startup The Exploration Company, which launched on June 23rd from the Vandenberg Space Force Base atop a Falcon-9 rocket as part of a rideshare mission (Transporter-14).
The payload for this flight (dubbed “Mission Possible”) included the ashes and DNA of more than 166 deceased people provided by Celestis, a Texas-based memorial spaceflight company.
Related: People Are Paying Big For Moon Burials And It Could Be Crossing a Concerning Line
While the mission achieved orbit and a controlled reentry, the capsule’s landing parachutes failed to deploy before landing. This caused the Nyx capsule to crash in the Pacific Ocean on June 24th, causing all of its cargo to be lost at sea.
Artist’s impression of the Nyx space capsule reentering Earth’s atmosphere. (The Exploration Company/ESA)
This was the first time The Exploration Company sent customer payloads to space, equivalent to roughly 300 kg (660 lbs) of cargo.
In a statement posted on LinkedIn, the company described the flight as a “partial success (partial failure).”
Per their statement:
The capsule was launched successfully, powered the payloads nominally in-orbit, stabilized itself after separation with the launcher, re-entered and re-established communication after black out. But it encountered an issue afterwards, based on our current best knowledge, and we lost communication a few minutes before splashdown. We are still investigating the root causes and will share more information soon. We apologize to all our clients who entrusted us with their payloads.
We thank our teams for their hard work and their dedication to success. We have been pushing boundaries in record time and cost. This partial success reflects both ambition and the inherent risks of innovation. Leveraging the technical milestones achieved yesterday and the lessons we will extract from our ongoing investigation, we will then prepare to re-fly as soon as possible.
This is also the second time Celestis has lost a payload, the previous having taken place in 2023 when a rocket containing the cremated remains of the late NASA astronaut Philip K. Chapman exploded over New Mexico.
Celestis also released a statement of condolences to the families of the people whose remains were lost:
In the coming days, our team will reach out to each family individually to offer support and discuss possible next steps. Though we currently believe that we cannot return the flight capsules, we hope families will find some peace in knowing their loved ones were part of a historic journey, launched into space, orbited Earth, and are now resting in the vastness of the Pacific, akin to a traditional and honored sea scattering.
In addition to the human remains and other payloads, Nyx also carried cannabis plant matter and seeds provided by Martian Grow, an open-source citizen science project.
The purpose was to study the effects of microgravity on the germination and resilience, potentially providing insight into how life could adapt and fare in the Martian environment.
The first, Mission Bikini, launched a smaller reentry capsule in July 2024 atop an Ariane 6 rocket, but the capsule remained in orbit after the rocket’s upper stage failed to launch it on its reentry trajectory.
This latest mission aimed to test key technologies and verify the Nyx capsule’s ability to transport cargo to space. It is hoped that future iterations of the capsule will fly spacecraft to destinations in Low Earth Orbit (LEO), including the International Space Station (ISS) and/or its successor stations.
To this end, the company plans to conduct a demonstration flight to the ISS in 2028, which is pending support from the European Space Agency. In the meantime, the company plans to move forward and incorporate the lessons of this latest mission.
This article was originally published by Universe Today. Read the original article.
Clocks might be far more fundamental to physics than we ever realized.
A new theory suggests what we see around us – from the smallest of quantum actions to the cosmic crawl of entire galaxies – could all be literally a matter of time. Three dimensions of time, in fact.
The basic idea of 3D time isn’t new. But University of Alaska geophysicist Gunther Kletetschka says his mathematical framework is the first to reproduce known properties of the Universe, making it a somewhat serious contender for uniting physics under one consistent model.
“Earlier 3D time proposals were primarily mathematical constructs without these concrete experimental connections,” says Kletetschka.
Related: Physicists Catch Light in ‘Imaginary Time’ in Scientific First
“My work transforms the concept from an interesting mathematical possibility into a physically testable theory with multiple independent verification channels.”
Something is wrong with our current models of reality. While quantum mechanics and general relativity both explain our Universe to a degree that’s uncannily accurate, each emerges from fundamentally distinct grounds – one granular and random, the other seamless and immutable.
These irreconcilable starting points make it a challenge to construct a single, all-ruling theory of physics that explains gravity in the same way as it does the other three forces. Not that theorists haven’t tried.
Kletetschka proposes a complete rethink on the basics, pulling back the fabric of space-time itself to come up with a new bedrock to base reality on.
While we use the word time to describe virtually any series of events, there’s a clear contrast in scale that extends from the near-instantaneous flitting of quantum particles to the eons of cosmic growth stretching into eternity.
On the cosmic end, time can be relative, distorting in relation to mass and acceleration. Up close, time is undecided, equally capable of looking to the past as it does to the future. And drifting in the middle is an existence as boringly predictable as tomorrow’s sunrise.
Separating these scales into their own dimensions provides us with three paths to follow, each marching to its own beat at right angles to the others.
Time flows in three dimensions in a new framework of physics. (Kletetschka, RAPS, 2025)
By embedding these timelines in mathematics that preserves cause and effect, it’s possible to link all three dimensions in a way that could explain everything from how fundamental particles pop up in quantum fields, to why we can’t experience quantum weirdness, to the expanding boundaries of the Universe itself.
“These three time dimensions are the primary fabric of everything, like the canvas of a painting,” says Kletetschka.
“Space still exists with its three dimensions, but it’s more like the paint on the canvas rather than the canvas itself.”
Related: A Fifth Force of Nature May Have Been Discovered Inside Atoms
Importantly, the framework precisely reproduces known masses of a number of particles, such as top quarks, muons, and electrons, and volunteers predictions for the unknown masses of neutrinos and subtle influences on the speeds of gravitational waves.
That means the theory could receive support from future experiments, and potentially contribute to a more united approach to physics as a whole.
“The path to unification might require fundamentally reconsidering the nature of physical reality itself,” says Kletetschka.
This research was published in Reports in Advances of Physical Sciences.
Clocks might be far more fundamental to physics than we ever realized.
A new theory suggests what we see around us – from the smallest of quantum actions to the cosmic crawl of entire galaxies – could all be literally a matter of time. Three dimensions of time, in fact.
The basic idea of 3D time isn’t new. But University of Alaska geophysicist Gunther Kletetschka says his mathematical framework is the first to reproduce known properties of the Universe, making it a somewhat serious contender for uniting physics under one consistent model.
“Earlier 3D time proposals were primarily mathematical constructs without these concrete experimental connections,” says Kletetschka.
Related: Physicists Catch Light in ‘Imaginary Time’ in Scientific First
“My work transforms the concept from an interesting mathematical possibility into a physically testable theory with multiple independent verification channels.”
Something is wrong with our current models of reality. While quantum mechanics and general relativity both explain our Universe to a degree that’s uncannily accurate, each emerges from fundamentally distinct grounds – one granular and random, the other seamless and immutable.
These irreconcilable starting points make it a challenge to construct a single, all-ruling theory of physics that explains gravity in the same way as it does the other three forces. Not that theorists haven’t tried.
Kletetschka proposes a complete rethink on the basics, pulling back the fabric of space-time itself to come up with a new bedrock to base reality on.
While we use the word time to describe virtually any series of events, there’s a clear contrast in scale that extends from the near-instantaneous flitting of quantum particles to the eons of cosmic growth stretching into eternity.
On the cosmic end, time can be relative, distorting in relation to mass and acceleration. Up close, time is undecided, equally capable of looking to the past as it does to the future. And drifting in the middle is an existence as boringly predictable as tomorrow’s sunrise.
Separating these scales into their own dimensions provides us with three paths to follow, each marching to its own beat at right angles to the others.
Time flows in three dimensions in a new framework of physics. (Kletetschka, RAPS, 2025)
By embedding these timelines in mathematics that preserves cause and effect, it’s possible to link all three dimensions in a way that could explain everything from how fundamental particles pop up in quantum fields, to why we can’t experience quantum weirdness, to the expanding boundaries of the Universe itself.
“These three time dimensions are the primary fabric of everything, like the canvas of a painting,” says Kletetschka.
“Space still exists with its three dimensions, but it’s more like the paint on the canvas rather than the canvas itself.”
Related: A Fifth Force of Nature May Have Been Discovered Inside Atoms
Importantly, the framework precisely reproduces known masses of a number of particles, such as top quarks, muons, and electrons, and volunteers predictions for the unknown masses of neutrinos and subtle influences on the speeds of gravitational waves.
That means the theory could receive support from future experiments, and potentially contribute to a more united approach to physics as a whole.
“The path to unification might require fundamentally reconsidering the nature of physical reality itself,” says Kletetschka.
This research was published in Reports in Advances of Physical Sciences.
Image: Dr Derek Keir, University of Southampton/ University of Florence
In East Africa’s Afar Depression, one of the only places on Earth where three tectonic plates meet, scientists have found compelling new evidence that fresh lava from deep within the mantle is playing a key role in the continent’s gradual splitting. Recent studies reveal that mantle upwellings beneath the region are not uniform but instead pulse upward in complex waves of molten material. This geological activity is not only fueling volcanic eruptions and earthquakes but is also actively weakening the crust. Over time, this process is expected to lead to the formation of a new ocean that will one day separate the Horn of Africa from the rest of the continent, transforming the geography of the region on a monumental scale.
Lava pulses and chemical striping reveal Earth’s deep inner workings
Scientists from the University of Southampton and Swansea University analyzed lava from over 130 young volcanoes across the Afar region. Their findings showed that the mantle beneath East Africa behaves like a beating heart, with pulses of partially molten rock rising to the surface. Each pulse carries its own distinct chemical signature, indicating that the mantle is not a single plume but a patchwork of different materials. This dynamic behavior is strongly influenced by the thickness and motion of the tectonic plates above.In fast-moving zones like the Red Sea Rift, mantle flow is more focused and intense. In slower rifting regions, it spreads more gradually. These pulses travel through thinned areas of the Earth’s crust, which are more susceptible to volcanic eruptions. The chemical “striping” in the lava mirrors cardiovascular rhythms and reflects the deep Earth’s internal tempo. This provides rare insight into how volcanic activity on the surface is tied to hidden processes occurring far beneath our feet.The plume’s action is also eroding the lithosphere, Earth’s outer shell, to just 15 kilometers thick in some parts of the Afar Depression. As the plates continue to stretch and thin, they create conduits for even more lava to reach the surface, leading to cycles of volcanic eruptions and seismic activity. This process mirrors events that shaped the Atlantic Ocean millions of years ago.
A continent breaks apart and a new ocean is born
The geological activity in the Afar region is part of a larger process known as continental rifting. Here, the African, Arabian, and Somali tectonic plates are moving away from each other. The space created between them is being filled with rising magma and new crust. Over time, as this rifting continues, seawater is expected to flow in and permanently flood the region. This will create a new ocean basin, much like the Atlantic that once separated Europe and North America.The current volcanic activity is already reshaping the surface. Lava from the Erta Ale volcano blankets large parts of Ethiopia, and frequent earthquake swarms mark zones of intense tectonic stress. The Boset Volcano shows layer upon layer of volcanic deposits, illustrating the long-term accumulation of geological events driven by the mantle’s upwelling.These findings not only offer a real-time glimpse into the birth of an ocean but also have implications for understanding Earth’s climate and history. Similar mantle plumes in the past have produced massive volcanic provinces like the North Atlantic Igneous Province, which contributed to significant climate changes and possibly even mass extinctions through the release of CO₂ and sulfur dioxide.Scientists emphasize that collaboration across institutions and disciplines is essential for understanding these complex dynamics. Future research will focus on mapping mantle flows beneath other thinning tectonic plates and predicting how these deep forces shape surface geology. Ultimately, the Afar region provides a natural laboratory for observing the connection between Earth’s interior and its evolving surface in action.
BEIJING, July 1 (Xinhua) — The China National Space Administration (CNSA) on Tuesday released images of Earth and the moon captured by the Tianwen-2 probe in orbit.
The CNSA said that the narrow-field-of-view navigation sensor equipped on the probe recently captured the images of Earth and the moon, demonstrating good functional performance.
The images released include a photograph of Earth obtained by Tianwen-2 when it was approximately 590,000 kilometers away from the planet, as well as a new photograph of the moon captured when it was about the same distance from the moon. After the images were transmitted back to the ground, they were processed and produced by scientific researchers.
The Tianwen-2 probe has currently been in orbit for over 33 days, at a distance from Earth exceeding 12 million kilometers, and it is in good working condition, the CNSA said.
China launched its first asteroid sample-return mission, Tianwen-2, on May 29 — an endeavour to shed light on the formation and evolution of asteroids and the early solar system.
The mission aims to achieve multiple goals over a decade-long expedition: collecting samples from near-Earth asteroid 2016HO3 and exploring main-belt comet 311P, which is farther from Earth than Mars. ■
Astronomers in Australia picked up a strange radio signal in June 2024 — one near our planet and so powerful that, for a moment, it outshined everything else in the sky. The ensuing search for its source has sparked new questions around the growing problem of debris in Earth’s orbit.
At first, though, the researchers thought they were observing something exotic.
“We got all excited, thinking we had discovered an unknown object in the vicinity of the Earth,” said Clancy James, an associate professor at Curtin University’s Curtin Institute of Radio Astronomy in Western Australia.
The data James and his colleagues were looking at came from the ASKAP radio telescope, an array of 36 dish antennas in Wajarri Yamaji Country, each about three stories tall. Normally, the team would be searching the data for a type of signal called a “fast radio burst” — a flash of energy blasting forth from distant galaxies.
“These are incredibly powerful explosions in radio (waves) that last about a millisecond,” James said. “We don’t know what’s producing them, and we’re trying to find out, because they really challenge known physics — they’re so bright. We’re also trying to use them to study the distribution of matter in the universe.”
Astronomers believe these bursts may come from magnetars, according to James. These objects are very dense remnants of dead stars with powerful magnetic fields. “Magnetars are utterly, utterly insane,” James said. “They’re the most extreme things you can get in the universe before something turns into a black hole.”
But the signal seemed to be coming from very close to Earth — so close that it couldn’t be an astronomical object. “We were able to work out it came from about 4,500 kilometers (2,800 miles) away. And we got a pretty exact match for this old satellite called Relay 2 — there are databases that you can look up to work out where any given satellite should be, and there were no other satellites anywhere near,” James said.
“We were all kind of disappointed at that, but we thought, ‘Hang on a second. What actually produced this anyway?’”
A massive short-circuit
NASA launched Relay 2, an experimental communications satellite, into orbit in 1964. It was an updated version of Relay 1, which lifted off two years earlier and was used to relay signals between the US and Europe and broadcast the 1964 Summer Olympics in Tokyo.
Just three years later, with its mission concluded and both of its main instruments out of order, Relay 2 had already turned into space junk. It has since been aimlessly orbiting our planet, until James and his colleagues linked it to the weird signal they detected last year.
But could a dead satellite suddenly come back to life after decades of silence?
To try to answer that question, the astronomers wrote a paper on their analysis, set to publish Monday in the journal The Astrophysical Journal Letters.
They realized the source of the signal wasn’t a distant galactic anomaly, but something close by, when they saw that the image rendered by the telescope — a graphical representation of the data — was blurry.
Shown above is the blurry image that left the astronomers scratching their heads, with the signal as a bright spot in the center. – Marcin Glowacki
“(T)he reason we were getting this blurred image was because (the source) was in the near field of the antenna — within a few tens of thousands of kilometers,” James said. “When you have a source that’s close to the antenna, it arrives a bit later on the outer antennas, and it generates a curved wave front, as opposed to a flat one when it’s really far away.”
This mismatch in the data between the different antennas caused the blur, so to remove it, the researchers eliminated the signal coming from the outer antennas to favor only the inner part of the telescope, which is spread out over about 2.3 square miles in the Australian outback.
“When we first detected it, it looked fairly weak. But when we zoomed in, it got brighter and brighter. The whole signal is about 30 nanoseconds, or 30 billionths of a second, but the main part is just about three nanoseconds, and that’s actually at the limit of what our instrument can see,” James said. “The signal was about 2,000 or 3,000 times brighter than all the other radio data our (instrument) detects — it was by far the brightest thing in the sky, by a factor of thousands.”
The researchers have two ideas on what could have caused such a powerful spark. The main culprit was likely a buildup of static electricity on the satellite’s metal skin, which was suddenly released, James said.
“You start with a buildup of electrons on the surface of the spacecraft. The spacecraft starts charging up because of the buildup of electrons. And it keeps charging up until there’s enough of a charge that it short-circuits some component of the spacecraft, and you get a sudden spark,” he explained. “It’s exactly the same as when you rub your feet on the carpet and you then spark your friend with your finger.”
A less likely cause is the impact of a micrometeorite, a space rock no bigger than 1 millimeter (0.039 inches) in size: “A micrometeorite impacting a spacecraft (while) traveling at 20 kilometers per second or higher will basically turn the (resulting) debris from the impact into a plasma — an incredibly hot, dense gas,” James said. “And this plasma can emit a short burst of radio waves.”
However, strict circumstances would need to come into play for this micrometeorite interaction to occur, suggesting there’s a smaller chance it was the cause, according to the research. “We do know that (electrostatic) discharges can actually be quite common,” James said. “As far as humans are concerned, they’re not dangerous at all. However, they absolutely can damage a spacecraft.”
NASA launched communications satellite Relay 2 in 1964. Three years later, Relay 2’s mission was over. – NASA
A risk of confusion
Because these discharges are difficult to monitor, James believes the radio signal event shows that ground-based radio observations could reveal “weird things happening to satellites” — and that researchers could employ a much cheaper, easier-to-build device to search for similar events, rather than the sprawling telescope they used. He also speculated that because Relay 2 was an early satellite, it might be that the materials it’s made of are more prone to a buildup of static charge than modern satellites, which have been designed with this problem in mind.
But the realization that satellites can interfere with galactic observations also presents a challenge and adds to the list of threats posed by space junk. Since the dawn of the Space Age, almost 22,000 satellites have reached orbit, and a little more than half are still functioning. Over the decades, dead satellites have collided hundreds of times, creating a thick field of debris and spawning millions of tiny fragments that orbit at speeds of up to 18,000 miles per hour.
“We are trying to see basically nanosecond bursts of stuff coming at us from the universe, and if satellites can produce this as well, then we’re going to have to be really careful,” James said, referring to the possibility of confusing satellite bursts with astronomical objects. “As more and more satellites go up, that’s going to make this kind of experiment more difficult.”
James and his team’s analysis of this event is “comprehensive and sensible,” according to James Cordes, Cornell University’s George Feldstein Professor of Astronomy, who was not involved with the study. “Given that the electrostatic discharge phenomenon has been known for a long time,” he wrote in an email to CNN, “I think their interpretation is probably right. I’m not sure that the micrometeoroid idea, pitched in the paper as an alternative, is mutually exclusive. The latter could trigger the former.”
Ralph Spencer, Professor Emeritus of Radio Astronomy at the University of Manchester in the UK, who was also not involved with the work, agrees that the proposed mechanism is feasible, noting that spark discharges from GPS satellites have been detected before.
The study illustrates how astronomers must take care to not confuse radio bursts from astrophysical sources with electrostatic discharges or micrometeoroid bursts, both Cordes and Spencer pointed out.
“The results show that such narrow pulses from space may be more common than previously thought, and that careful analysis is needed to show that the radiation comes from stars and other astronomical objects rather than man-made objects close to the Earth,” Spencer added in an email.
“New experiments now in development, such as the Square Kilometre array Low frequency array (SKA-Low) being built in Australia, will be able to shed light on this new effect.”
Clarification: This story has been updated to clarify the time frame in which the strange radio signal was detected.
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Newswise — Animals, from worms and sponges to jellyfish and whales, contain anywhere from a few thousand to tens of trillions of nearly genetically identical cells. Depending on the organism, these cells arrange themselves into a variety of tissues and organs, such as muscles, sensory systems, or the gut. While not all animals have each of these tissues, they do all have one tissue, the germline, that produces sperm or eggs to propagate the species.
Scientists don’t completely understand how this kind of multicellularity evolved in animals. Cell-to-cell adhesion, or the ability for individual cells to stick to each other, certainly plays a role, but scientists already know that the proteins that serve these functions evolved in single-celled organisms, well before animal life emerged.
Now, research from the University of Chicago provides a new view into key innovations that allowed modern, multicellular animals to emerge. By analyzing the proteins predicted from the genomes of many animals (and close relatives to the animal kingdom), researchers found that animals evolved a more sophisticated mechanism for cell division that also contributes to developing multicellular tissues and the germline.
“This work strongly suggests that one of the early steps in the evolution of animals was the formation of the germline through the ability of cells to stay connected by incomplete cytokinesis,” said Michael Glotzer, PhD, Professor of Molecular Genetics and Cell Biology at UChicago and author of the new study. “The evolution of three proteins allowed both multicellularity and the ability to form a germline: two of the key features of animals.”
Positioning the division plane
Cell division, or cytokinesis, is the process by which a cell divides into two distinct daughter cells. Many of the proteins involved with cytokinesis are ancient, present long before the first Metazoa arose about 800 million years ago.
Glotzer has been studying animal cell division for several decades, focusing on how cells determine where to divide. In animal cells, a structure called the mitotic spindle segregates the chromosomes before the cells divide; it also dictates the position where cell division occurs. Glotzer and his team homed in on a set of three proteins—Kif23, Cyk4, and Ect2—that bind to each other and the spindle, and which are directly involved in establishing the division plane. Close relatives of these proteins had only been found in animals previously.
Two of these proteins, Kif23 and Cyk4, form a stable protein complex called centralspindlin that Glotzer and his colleagues discovered more than 20 years ago. Not only does centralspindlin contribute to division plane positioning, but it also generates a bridge between the two incipient daughter cells.
The cells that make up non-germline tissues and organs are called somatic cells, which are not passed on to the next generation. Germline cells are special because they can become any cell type. During the development of sperm and eggs, these cells also recombine the chromosomes they inherited from their parents, generating genetic diversity. While centralspindlin-dependent bridges are generally severed in somatic cells, the germlines of most animals have cells that remain connected by stable bridges.
Tracking down the proteins
Given the recent explosion in genome sequence data now available for a wide range of animals, Glotzer first wanted to determine if the two proteins that make up the centralspindlin complex, as well as Ect2, the regulatory protein that binds to it, were present and well conserved in all animals. During his analysis for this study, which was published in Current Biology, he found that all branches of animals have all three of these proteins.
Studies of these proteins in species commonly used in the lab discovered common patterns that are linked to their known functions. Using Google DeepMind’s AlphaFold AI platform (developed by UChicago alum and recent Nobel Laureate John Jumper), Glotzer was able to predict the interactions among these different proteins and found that every interaction is likely conserved across all animals. This suggests that these proteins were all in place at the beginning of the animal kingdom more than 800 million years ago and have not undergone any dramatic changes since that time.
Next, Glotzer wondered whether any related proteins could be found in single-celled organisms. He identified somewhat related proteins in choanoflagellates, the group of single-celled creatures most closely related to animals. Alphafold predicted that some of them can form a complex somewhat like centralspindlin. Though related, these complexes are clearly distinct from centralspindlin, and they lack the sequences that allow Ect2 to bind to the structure. Remarkably, some choanoflagellate species that have this complex can form colonies via incomplete cytokinesis too.
“Pre-metazoan cells have mechanisms of dividing and separating, probably with some themes and variations. Then this protein complex allowed cells to stop at the stage just before separation,” Glotzer said. “Maybe multicellular life evolved because of a genetic change that prevented cells from fully separating.”
“A mutation that disrupted the assembly of centralspindlin is what allowed my colleagues and me to find these proteins in the first place, more than 25 years ago,” he continued. “And it appears that the evolution of this exact same region contributed to the evolution of animal life on the planet, which is mind blowing.”
The study, “A key role for centralspindlin and Ect2 in the development of multicellularity and the emergence of Metazoa,” was supported by the National Institutes of Health.
Paleontologists have identified a new genus and species of mid-sized pareiasaur from two fossilized specimes found in China in 2018.
An artist’s reconstruction of Yinshanosaurus angustus. Image credit: X.-C. Guo, Institute of Vertebrate Paleontology and Paleoanthropology.
Named Yinshanosaurus angustus, the newly-identified species roamed Earth during the latest Permian period, between 259 and 254 million years ago.
The ancient beast was a member of Pareiasauria, a specialized group of herbivorous tetrapods that existed throughout the supercontinent Pangea during the Middle-Late Permian.
“Pareiasauria are a bizarre herbivorous clade of tetrapods that existed in the Guadalupian and Lopingian and were victims of both the Late Capitanian and the end-Permian mass extinction events,” said Dr. Jian Yi and Jun Liu from the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences, the University of Chinese Academy of Sciences, and Chongqing Institute of Paleontology.
“Pareiasauria has a worldwide distribution, with fossils discovered in Africa, Europe, Asia and South America.”
“Pareiasaurs were common primary consumers in several terrestrial tetrapod faunas, including the Late Permian fauna of northern China.”
“Since the 1960s, eight Chinese pareiasaur species have been described.”
Two specimens — a nearly complete skull and an articulated partial postcranial skeleton with a nearly complete skull — were unearthed in China in 2018.
“The first specimen was excavated form the dark purple siltstone in the lower part of the Sunjiagou Formation, near Zhangjiagetuo village, Baode county, Xinzhou city, Shanxi,” the paleontologists said.
“The second specimen was excavated from purplish silty mudstone in the upper part of Member I of the Naobaogou Formation, near Qiandian village, Shiguai district of Baotou City, Nei Mongol.”
According to the authors, Yinshanosaurus angustus had the narrowest skull of all pareiasaurs, with skull length more than twice the skull width at the lateral edges of the cheeks.
“The skeleton of Yinshanosaurus angustus provides the complete cranial and articulated postcranial details of Chinese pareiasaurs for the first time,” they said.
Their paper was published this month in the journal Papers in Palaeontology.
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Jian Yi & Jun Liu. 2025. The tetrapod fauna of the upper Permian Naobaogou Formation of China: a new mid-sized pareiasaur Yinshanosaurus angustus and its implications for the phylogenetic relationships of pareiasaurs. Papers in Palaeontology 11 (3): e70020; doi: 10.1002/spp2.70020
