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Ancient 773,000-Year-Old Hominin Fossils from Morocco Shed Light on the Origins of Homo sapiens

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Recent discoveries of hominin fossils in the Thomas Quarry I cave located in Casablanca, Morocco, provide crucial insights into the early origins of homo sapiens. These findings indicate that the lineage leading to modern humans was potentially established in Africa nearly 800,000 years ago. The fossils, although similar in age to the ancestor of homo discovered in Spain, display a mix of primitive and advanced traits reminiscent of post-Eurasian hominins, including homo sapiens.

Reconstruction of homo erectus.

Paleoanthropologists have long debated the origins of Neanderthals and Denisovans, the last common ancestors of modern humans. Genetic studies reveal that this ancestor likely existed between approximately 765,000 and 550,000 years ago, although fossil records are still inconclusive.

While some researchers have posited a Eurasian origin based on fossils unearthed in Atapuerca, Spain, dating back to 950,000 to 770,000 years ago, the new findings from Morocco reinforce the theory of an African origin.

Recent discoveries from the Moroccan cave, including mandible fragments, teeth, vertebrae, and femur pieces, bolster the evidence supporting Africa as the cradle of human evolution.

Analysis of the sediments surrounding these fossils indicates that they date back approximately 773,000 years, coinciding with significant changes in the Earth’s magnetic field, aligning with the era of the ancestor of homo.

Interestingly, the new fossils present distinct morphological differences. The evidence suggests that regional differentiation between Europe and North Africa was already evident by the late Early Pleistocene, spanning from around 1.8 million to 780,000 years ago.

The Moroccan fossils exhibit a blend of primitive features linked to species like homo erectus alongside more modern traits found in homo sapiens and Neanderthals.

For instance, their molar size aligns with earlier homo sapiens fossils, while the jaw shape resembles that of Neanderthals and other African archaic humans.

Although the Moroccan fossil may not serve as the ultimate last common ancestor of modern humans, Neanderthals, and Denisovans, it is likely a close precursor.

“The Moroccan fossils likely represent an advanced form of homo erectus in North Africa, situated on a lineage close to the evolutionary divergence between African and Eurasian lineages,” stated the researchers.

“Our findings underscore the Maghreb region as vital for understanding the emergence of our species and strengthen the argument for an African origin of homo sapiens,” they concluded.

Findings are detailed in a recent study published in Nature.

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J.J. Havlin and colleagues. Early human fossils from Morocco and the emergence of homo sapiens. Nature, published online January 7, 2026. doi: 10.1038/s41586-025-09914-y

Source: www.sci.news

Make This Easy Diet Change to Shed Pounds Effortlessly.

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Shedding pounds might be as straightforward as swapping out some sausages, beef, and bacon in your meals for legumes. Recent research highlights this find.

Researchers from the University of Helsinki directed 51 Finnish men, aged 20-65, to cut back on their red and processed meat intake by just 200g (7oz) a week.

Simultaneously, these men incorporated more legumes, particularly peas and fava beans, into their diets, constituting 20% of their protein sources, while still consuming chicken, fish, eggs, and other proteins.

Apart from this substitution, participants were not advised to eat less or restrict calories. Remarkably, just six weeks later, they experienced an average weight loss of 1 kilo (2.2 pounds).

“This was astonishing because we didn’t set out to encourage weight loss,” said Professor Anne Maria Pajari, a molecular dietitian and senior author of the study, as reported by BBC Science Focus. “We encouraged volunteers to maintain their daily eating habits while monitoring their red and processed meat and legume consumption.”

Pajari noted that while legumes are associated with healthy weight, the degree of change observed in just six weeks was unexpected. This was just the beginning.

By the study’s conclusion, participants consuming legumes had lower total and LDL (“bad”) cholesterol levels, indicating that this dietary switch could lower heart disease risk.

Moreover, the men’s iron levels improved, an outcome surprising since lean meat is typically regarded as a primary source of dietary iron.

According to Pajari, the food exchange was well-received by participants; only one volunteer chose to leave the study.

“I’m very satisfied with the results,” Pajari remarked. “This is something everyone can do. By cutting back on red and processed meat and incorporating more plant-based foods, individuals can make a meaningful impact on their health.”

“Even small adjustments can lead to significant benefits for both personal health and the environment,” she added.

The focus on men specifically was intentional, as they generally consume more meat compared to women.

Pajari observed that in Finland, the average man consumes double the amount of meat than the average woman, making men a “more vulnerable group” in terms of red and processed meat intake.

Lean meats include beef, pork, and lamb, while processed meats consist of cold cuts, sausages, and bacon – Credit: via Guido Mieth

The study also involved control groups, with another 51 men consuming 760g (27oz) of red and processed meats weekly—making up a quarter of their total protein intake, without any legumes.

This group showed no notable improvement in their blood cholesterol or iron levels and lost only 300g (0.6 pounds) on average. Pajari suggested this was merely a byproduct of participating in dietary trials.

“Participation in a diet trial often raises awareness about one’s eating habits,” she explained. “It’s quite sensitive, leading individuals to make healthier choices even when not instructed to.”

Overall, Pajari hopes that men will consider substituting some red and processed meats in their diets with peas, beans, and lentils for the sake of their health and the planet.

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Source: www.sciencefocus.com

Neanderthal-Shaped Skulls Could Shed Light on Why Some Individuals Experience Headaches

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3D Models of Skulls from Modern Humans and Neanderthals

Courtesy of Kimberly Anne Plomp

Abnormalities in the skull that compress the lower brain can lead to headaches and various neurological issues, potentially passed down from Neanderthals.

Individuals with Chiari malformations possess a smaller, flatter skull base near the spine junction, causing the cerebellum to be pressed into the neck’s spinal canal.

Type 1 Chiari malformations, which are the least severe, may impact about 1 in 100 individuals. Symptoms can include headaches, neck pain, sleep apnea, and numbness, although some may remain asymptomatic.

Approximately 15 years ago, Yvens Barbosa Fernandes, a neurosurgeon at Campinas State University in Brazil, observed that the skull base of his Chiari patients bore resemblance to Neanderthal specimens from the European Museum, particularly the gentle slopes of the occipital bone where the cerebellum rests. Neanderthals had larger brains than modern humans, yet their skulls were more oblique at the foreheads and bases, resulting in a flatter shape compared to the rounder modern human skulls.

In 2013, Barbosa Fernandes published his hypothesis, suggesting that the shape of Chiari skulls could have a genetic link to an extinct human species, Homo sapiens. “In Chiari’s case, I began to consider a lost connection between anthropology and medicine,” he stated.

Motivated by this theory, Kimberly Plomp from the University of the Philippines in Quezon City and her team created digital 3D models of 46 Chiari 1 skulls and 57 unaffected skulls using CT scans. Their comprehensive mathematical analysis confirmed that the Chiari-affected skulls exhibited more cerebral compression at a flat angle at the base where the cerebellum is located.

Subsequently, the group compared these recent skulls with digital models of eight fossilized heads from Homo Neanderthalensis, Homo Erectus, Homo Heidelbergensis, and ancient Homo sapiens.

They discovered that the skull base measurements of Neanderthal heads closely matched those of modern humans with Chiari, while the skull bases of all other ancient species resembled typical modern humans without Chiari. “This underscores the notion that these modern humans may share Neanderthal characteristics,” suggesting another way Neanderthal genes could influence our health.

For Barbosa Fernandes, this research offers solid backing for his hypothesis. “It makes sense; a less pronounced angle results in less space for the modern human brain,” he noted. “Until now, I lacked scientific evidence to support my theory. This research brings me significantly closer to that proof.”

Looking ahead, the team intends to analyze the DNA of individuals with Chiari malformations in search of Neanderthal genetic markers, according to Plomp.

Other Chiari malformations (types 2-4) are believed to stem from various causes. Type 2 is associated with severe forms of spina bifida, while types 3 and 4 are exceedingly rare and can pose life-threatening risks.

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Source: www.newscientist.com

Insightful Discoveries: New Fossils Shed Light on Plesiosaurus Diversity and Local Adaptations

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German paleontologists have unearthed a very well-preserved skeleton of the early Jornaian plesiosauloid species Plesioptery Wildi.

MH 7 Skeleton Plesioptery Wildi Abdominal view. Image credit: Marx et al. , doi: 10.7717/peerj.18960.

From a global perspective, the early Jurassic was characterized by the steady division of the Supercontinent Pangaea and associated climate change that produced alternating greenhouses and ice house conditions.

These paleoenvironmental changes coincided with radiation in various reptile groups. Plesiosauria.

The early Jurassic fossil records of the Plesiosaurus are particularly diverse, with members of Plesiosauroidea, Pliosauridae and Rhomaleosauridae being represented by numerous species in Europe, particularly in Germany and the UK.

3 m long skeleton Plesioptery Wildi It provides new clues about the evolution and geographical distribution of early Jurassic Precio Sources.

Fossils that were 180 million years ago posidonienschiefer layer Near Holtzmadden in southern Germany.

The specimen, called MH 7, is one of the most complete and distinct plesioaurus skeletons found in the region.

“Unlike the fishy scallions and marine crocodile parents who dominate the fossil record of this formation, Pleciosaurus is relatively rare,” said Miguel Marx, a paleontologist at Lund University and his colleagues.

“Therefore, new discoveries offer rare glimpses into the biodiversity of these long-necked marine reptiles.”

“MH 7 represents someone who refines this type of known trait and refines its validity as a clear taxa.”

Phylogenetic analysis shows that Plesioptery Wildi It is a close-related early potential plesiosaualoid Franconiasaurus Brevispinus.

“This finding suggests a progressive evolutionary transition to more derived cryptocrizids in the late Jurassic period,” the paleontologist said.

“It supports the idea that Prisiosaurus species may have been regionally different in the Epicontoninent Seas of early Jurassic Europe, reinforcing the pattern of paleobiogeographic segregation.”

“The Holtzmadden specimen gives us an unprecedented view Plesioptery Wildi At a more mature stage of development, we can refine our understanding of this species and its place in the evolution of plesiosaurus,” said Dr. Marx.

“It also suggests that different plesiosaurus communities may have evolved in different regions of the European sea during the early Jurassic region.”

“Our research reinforces the Pleciosoaurus already evolves specialized adaptations and distinct regional lineages much faster than we believed,” added Dr. Sven Sachs, a researcher at the Naturkunde Museum Bielefeld.

“This has important implications for understanding how marine reptiles responded to changes in the Jurassic ocean environment.”

study Published in the journal Peerj.

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M. Marx et al. 2025. New specimen of Plesioptery Wildi We reveal the diversification and possible uniqueness of Cryptocrizia precursors in the early European Jurassic Plecioaurauro assembly. Peerj 13:E18960; doi:10.7717/peerj.18960

Source: www.sci.news

Rare footage of a mother polar bear and her cubs emerging from their den shed light on their elusive behavior

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It's published today International Polar Bear Daynew research will answer questions by showing the first combination of satellite tracking colors and remote camera traps Polar bear (Ursus Maritimus)) Denning is notoriously difficult to study as polar bear moms create dens under the snow in remote areas.

Shooter et al. It reveals the first detailed view of polar bear cults coming out of their burrows. Image credits: Jon Aars/Norwegian Polar Institute.

Turnip survival supports species survival, and denning is the most vulnerable period of life. Less than 50% of Cubs can become adults.

As industry expands in the Arctic, this study highlights the importance of uninterrupted Denning regions to protect polar bear populations.

“Polar bear mothers have increased difficulty replicating due to climate-based changes and could face additional challenges associated with expanding human footprints in the Arctic,” said Dr. Louise Archer, a researcher at the University of Toronto Scarborough University.

“We are excited to introduce new tools to monitor bears during this vulnerable period and gain insight into action across the Arctic.

“Every den we monitor has its own story, and every data point adds to this critical understanding of time and supports a more effective conservation strategy.”

In their study, the authors monitored the behavior of the polar bears in Den Emans held in Svalbad, Norway.

Female polar bears were equipped with GPS satellite collars recording their location, temperature and activity.

Researchers used these collar data to find burrows and traveled through the mountains of Svalbad to deploy time-lapse camera traps at 13 densites over six years.

They found that camera traps provide fine-scale insight into the behavior of the maternal Den, and that satellite collars are accurate and useful for monitoring bears in more remote locations for longer periods of time.

https://www.youtube.com/watch?v=fcf0fyq_e_i

The family appeared in Svalbarbad around March 9th and appeared to abandon the burrow earlier than previously recorded in this group, and further monitoring was needed to establish whether this was a continuing trend.

Changing the timing of denning can put a risk to the cubs' survival as they will less time to develop before they can proceed further towards the sea ice.

In some cases, the bears appeared from the burrow in less than a minute before returning inside, while other appearances lasted for several hours.

In terms of departing den forever, camera footage showed that polar bears remained near the burrow to stay on average for 12 days.

However, this ranged between 2-31 days and was very different among polar bear families.

Some moms switched dens – they were observed leaving their original dens and moving their families to new dens.

Cubs are heavily dependent on their mothers and rarely venture out in their dens alone. The Cubs were only seen in 5% without mothers. In Svalbad, they rely on their mothers for up to 2.5 years.

“This study gives us a total glimpse into one of the most vulnerable and important periods of polar bear life and provides insights that will help guide our collective conservation efforts.”

“Combining innovative technology and long-term research gives us a deeper understanding of the challenges faced by polar bear moms and cubs in the rapidly changing Arctic.”

“Conserving Denning's habitat is essential for population health, and this study provides invaluable insights that can help guide conservation management.”

“There were few studies that included observational data at polar bear burrow sites, and therefore this study contributes significantly to our knowledge of denning ecology,” said Dr. John Arles, a senior researcher at the Norwegian Polar Institute.

Furthermore, data from the satellite radio collar was available to all mothers, and observational data allowed us to communicate how recorded activity and temperature changes corresponded to behavior. ”

study It will be displayed in Journal of Wildlife Management.

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Louise C. Archer et al. Monitoring the phenology and behavior of polar bears during the emergence of den using cameras and satellite telemetry. Journal of Wildlife ManagementPublished online on February 26th, 2025. doi: 10.1002/jwmg.22725

Source: www.sci.news

Advancements in Research Shed Light on Habitability of Oceanic Worlds in Our Solar System and Beyond

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In a new paper, planetary researchers from Texas A&M University and the University of Washington introduce a new thermodynamic concept called centotectics to investigate the stability of liquids under extreme conditions. This is important information for determining the habitability of icy moons and oceanic exoplanets.

Europa's surface stands out in this newly reprocessed color view. Image scale is 1.6 km per pixel. North of Europe is on the right. Image credit: NASA / JPL-Caltech / SETI Institute.

Exploration of icy ocean worlds represents a new frontier in planetary science, with a focus on understanding the potential of these environments to support life.

New research is addressing fundamental questions in this field. Under what conditions can liquid water remain stable on these distant frozen bodies?

The authors provide an important framework for interpreting data from planetary exploration activities by defining and measuring the cenotect, the absolute minimum temperature at which a liquid remains stable under various pressures and concentrations.

This research combines their expertise in cryobiology with their expertise in planetary science and high-pressure water ice systems.

Together, they developed a framework that bridges the disciplines to tackle one of the most fascinating challenges in planetary science.

2016 artist concept for the European Clipper spacecraft. As spacecraft development progresses, the design changes. Image credit: NASA/JPL-Caltech.

“The launch of NASA's Europa Clipper, the largest planetary exploration mission ever launched, ushered us into a decades-long era of exploration of the frigid ocean world,” said Dr. Baptiste Journeau, a planetary scientist at the University of Washington. It's coming in,” he said.

“Measurements from this and other missions will tell us the depth of the ocean and its composition.”

“Laboratory measurements of liquid stability, particularly the lowest possible temperature (a newly defined cenotect), combined with the mission results will help us determine how habitable the solar system's cold, deep oceans are, and how likely they will ultimately be. It will be possible to completely constrain what the temperature will be.''The fate would be when the moon or planet cools down completely. ”

“The study of icy worlds is a particular priority for both NASA and ESA, as evidenced by the spate of recent and upcoming spacecraft launches,” said Dr. Matt Powell-Palm, a planetary scientist at Texas A&M University. Ta.

“We hope to help Texas A&M provide intellectual leadership in this area.”

of paper Published in the Journal on December 18, 2024 nature communications.

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A. Zaris others. 2024. On the equilibrium limit of liquid stability in pressurized water systems. nut community15;doi: 10.1038/s41467-024-54625-z

Source: www.sci.news

Fossils from Mid-Devonian coral reefs shed light on early photosymbiosis evidence

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The symbiotic relationship between corals and their photosynthetic partners, algae (photosymbionts), dates back to at least the Devonian period (385 million years ago), according to a new study.

Dendroid Porites Coral Dendrostella trigeum tab-shaped coral fragments Romerolite Brevis Riphaeus. Image credit: Chong others., doi: 10.1038/s41586-024-08101-9.

All modern corals belong to a group called scleractinians, which evolved during the Triassic period.

These corals may provide habitat for symbionts (such as photosymbionts) that play a role in nutrient recycling, which is especially beneficial in nutrient-poor waters.

However, it is not clear whether earlier extinct forms of coral had photosymbionts.

“The Devonian period (419 to 359 million years ago) was a time when sea surface temperatures and atmospheric carbon dioxide were higher than they are today,” said Jonathan Jung, a researcher at the Max Planck Institute for Chemistry, stated in their paper.

“Unlike today, its carbonate chemistry is dominated by calcite precipitation, likely due to the low magnesium-to-calcium ratio in seawater.”

“The Middle Devonian was the period of greatest expansion of metazoan reefs in the Phanerozoic era, and well-preserved reefs from this period span what is now Europe, North America, North Africa, Australia, Siberia, and China.” explained the researchers.

“In the Devonian period, these reefs bordered the lake seas on the southern margin of Lorsia and the northern boundary of Gondwana.”

“Along the southern margin of Lorsia, these ancient reef communities reached their greatest extent and highest diversity during the Givetian period of the Devonian period (approximately 387 to 382 million years ago).”

“These thriving metazoan coral reefs became diachronically extinct during the course of the Kerwasser crisis in the Late Fraznian (372.2 million years ago).”

“Then, coral reefs were built primarily by cyanobacteria/algae, which were present in very small numbers until the end of the Famenian period (Devonian-Carboniferous boundary).”

“The ability to host photosymbionts was paramount to the ecological success of ancient coral reef communities during the Givetian period, and the subsequent collapse of coral reefs in the Late Devonian was associated with a gradual loss of photosymbiotic relationships. It is suggested that

“However, there is still no clear consensus as to whether photosymbiosis was prevalent in now-extinct coral groups during the Paleozoic era.”

In their study, Dr. Jung and his co-authors examined fossils of two extinct reef coral groups from the mid-Devonian period: the tabula corals and the shibo corals.

They measured nitrogen isotopes bound to corals (15no/14N), can be used to distinguish whether corals obtain energy from photosynthetic symbionts.

Their results suggest that symbionts were present in the tabular corals they studied, but not in most civet corals.

This discovery provides definitive geochemical evidence of the oldest known example of symbiosis in corals.

“Wide-spread oligotrophy during the Devonian may have promoted coral photosymbiosis, and its occurrence may explain why Devonian reefs were the most productive reef ecosystems of the Phanerozoic.” the researchers wrote in their paper.

“These early signals of photosymbiosis in mid-Devonian corals indicate that it supported coral productivity under warm climate conditions.”

“The Late Triassic and Early Miocene (the subsequent period when coral photosymbiosis was reconstructed using nitrogen isotopes) were also warmer than today.”

“In contrast, under modern global warming caused by anthropogenic greenhouse gas emissions, coral bleaching and associated mass mortality events are likely the greatest threat to the future of coral reefs, with the disruption of coral symbiosis due to warming.” It shows that there is.”

“The strength of coral photosymbiosis in past warm climates suggests that the failure of coral symbiosis under ongoing global warming will not be due to an increase in ocean surface temperatures reached, but rather an increase in ocean surface temperatures.” This shows that the rate of increase is greater than the adaptive capacity of the symbiotic relationship.

team's paper appear in the diary nature.

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J. Jung others. Coral photosymbiosis on mid-Devonian coral reefs. naturepublished online October 23, 2024. doi: 10.1038/s41586-024-08101-9

Source: www.sci.news

New excavations shed light on early human activity in Laos’ jungles

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Archaeologists excavating Tam Parin (Monkey Cave) in northeastern Laos have discovered some of the earliest fossil evidence homo sapiens Presence in mainland Southeast Asia.

Excavation survey at Thamparin in northeastern Laos. Image credit: Hernandez others., doi: 10.1016/j.quascirev.2024.108982.

“Using a technique known as microstratigraphy, we were able to reconstruct past cave conditions and identify traces of human activity in and around Tamparin,” said Flinders University's Ph.D. says. Candidate Vito Hernandez.

“This also helped us determine the exact conditions in which some of the earliest modern human fossils found in Southeast Asia were deposited at depth.”

Microstratigraphy allows scientists to study soils in minute detail, identifying structures and features that preserve information about past environments, as well as potential structures and features that were overlooked during the excavation process due to their small size. Even traces of sexual human and animal activity can be observed.

The hominin fossils discovered by archaeologists were deposited in Tamparin Cave between 86,000 and 30,000 years ago.

However, until now, no detailed analysis of the sediment surrounding these fossils has been conducted to understand how they were deposited in the cave or the environmental conditions at the time.

The new findings reveal that conditions within the cave varied dramatically, from a temperate climate with frequently wet ground conditions to a seasonally dry climate.

Dr Mike Morley from Flinders University said: “This environmental change would have affected the topography inside the cave and influenced how the deposits containing hominin fossils were deposited inside the cave.” said.

“How fast! homo sapiens The theory that they were buried deep inside the cave has long been debated, but our analysis of the sediments suggests that the fossils were pushed into the cave as loose sediment and debris that accumulated over time and were washed away by heavy rains. It has been shown that it was likely carried by water from the surrounding hillsides. ”

Researchers have also identified tiny traces of charcoal and ash preserved in the cave's sediments, indicating that forest fires occurred in the area during the dry season, or that humans visited the cave. This suggests that fire may have been used inside the cave or near the entrance. .

“With this study, our team gained unprecedented insight into the dynamics of our ancestors, who dispersed throughout Southeast Asia's ever-changing forest cover and during periods of regional climate instability.” ,” said Dr. Fabrice Demeter, a paleoanthropologist at the National Museum of Nature and Science. University of Copenhagen.

of result Published in a magazine dated October 10th Quaternary Science Review.

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VC Hernandez others. Late Pleistocene–Holocene (52–10 ka) microstratigraphy, fossil taphonomy, and depositional environment of Tam Parin Cave (northeastern Laos). Quaternary Science Reviewpublished online October 10, 2024. doi: 10.1016/j.quascirev.2024.108982

Source: www.sci.news

Lunar samples shed light on the formation of the Moon’s largest crater

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Lunar samples collected by NASA's Apollo missions continue to enable new discoveries.

NASA/ESA

The Moon's largest crater is thought to have formed 4.338 billion years ago when a huge rock struck the lunar surface, leaving behind a swirling pool of magma, suggesting that Earth was experiencing extreme cosmic upheaval at the same time.

Chemical analysis of tiny zircon crystals found in lunar samples revealed that many of them solidified from magma about 4.3 billion years ago, but without measuring whether they all formed at precisely the same time, there was no way to know for sure whether many small impacts or one giant one melted the lunar crust into magma.

Melanie Balboni Balboni and her colleagues at Arizona State University solved this problem by measuring with extreme precision the ages of 10 zircon crystals that were brought back to Earth as part of NASA's Apollo missions. “To do this kind of dating, you have to melt the zircon,” Balboni says. “The lunar material is so precious, and there are so few reliable labs in the world that can do that, so no one has dared to do it. When I first did it, I was so scared.”

The researchers found that the crystals all formed at the same time, 4.338 billion years ago, which indicates that they likely formed in one giant impact. The same impact that created these crystals probably also formed the South Pole-Aitken Basin, the largest crater on the Moon, unless that impact crater was subsequently obscured by shifting sand or other impactors, Balboni says.

Not only is this a pivotal event in the history of the Moon, but it also tells us something about the space environment on Earth at that time. “The Moon is a very small object compared to Earth, so it was very likely that something very big struck Earth at that time,” Balboni said. “That big rock could have left behind cosmic gifts, like water, that might have helped the birth of life.”

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Source: www.newscientist.com

New discoveries from the Webb telescope shed light on the origins of supermassive black holes and galaxies

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New insights from the NASA/ESA/CSA James Webb Space Telescope overturn theories about how black holes shape the universe, reversing the classical theory that black holes formed after the first stars and galaxies appeared. It challenges our understanding. In fact, black holes may have accelerated the birth of new stars during the universe's first 50 million years.

This artist's impression shows the evolution of the universe, starting with the Big Bang on the left and continuing with the emergence of the Cosmic Microwave Background. The formation of the first stars ends the Dark Ages of the universe, followed by the formation of galaxies. Image credit: M. Weiss / Harvard-Smithsonian Center for Astrophysics.

“We know that these monster black holes exist in the centers of galaxies near the Milky Way, but now the big surprise is that they were also present at the beginning of the universe, and that they were like building blocks or seeds of early galaxies. It was something,” he said. Professor Joseph Silk, an astronomer at Johns Hopkins University and the Sorbonne Institute of Astrophysics;

“They've really enhanced everything, including giant amplifiers for star formation. This completely overturns what we previously thought was possible, and how galaxies form. It has the potential to completely shake up our understanding of what happens.”

“The distant galaxies observed by Webb in the early universe appear much brighter than scientists expected, revealing an unusually large number of young stars and supermassive black holes.”

“Conventional wisdom holds that black holes formed after the collapse of supermassive stars, and that galaxies formed after the first stars illuminated the dark early universe.”

But the team's analysis suggests that for the first 100 million years, black holes and galaxies coexisted, influencing each other's fate.

“We argue that the outflow of the black hole crushed the gas clouds and turned them into stars, greatly accelerating the rate of star formation,” Professor Silk said.

“Otherwise, it's very difficult to understand where these bright galaxies came from, because they are typically smaller in the early Universe. Why on earth did they become stars so quickly? Do I need to create one?”

“A black hole is a region of space where gravity is so strong that not even light can escape its attraction.”

“Thanks to this force, they generate powerful magnetic fields that cause violent storms, eject turbulent plasma, and ultimately act like giant particle accelerators.”

“This process may be why Webb's detectors found more black holes and brighter galaxies than scientists expected.”

“We can't fully see these ferocious winds and jets so far away, but we know they must exist because many black holes have been seen in the early universe. I am.”

“The huge wind blowing from the black hole crushes nearby gas clouds, turning them into stars.”

“This is the missing link that explains why these first galaxies are much brighter than we expected.”

According to the research team, there were two stages of the young universe.

In the first stage, star formation was accelerated by high-velocity outflow from the black hole, while in the second stage, the outflow slowed down.

“Hundreds of millions of years after the Big Bang, a supermassive black hole magnetic storm caused gas clouds to collapse and new stars to form at a rate far exceeding that observed in normal galaxies billions of years later,” Professor Silk said. Ta.

“These powerful outflows moved into energy conservation states, reducing the amount of gas available to form stars within the galaxy, thus slowing star formation.”

“We originally thought that galaxies formed when giant gas clouds collapsed,” Professor Silk said.

“The big surprise was that there was a seed in the middle of that cloud, a large black hole, that helped rapidly turn the inside of that cloud into a star at a much faster rate than we expected. So the first galaxies are incredibly bright.”

of study Published in Astrophysics Journal Letter.

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joseph silk other. 2024. Which came first, a supermassive black hole or a galaxy? Insights from JWST. APJL 961, L39; doi: 10.3847/2041-8213/ad1bf0

Source: www.sci.news

Fossils dating back 1.75 billion years shed new light on the evolution of photosynthesis

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Microscopic image of a modern cyanobacterium called Oscillatoria

Shutterstock / Ekki Ilham

Researchers have identified photosynthetic structures inside a 1.75 billion-year-old cyanobacteria fossil. This discovery is the oldest evidence yet of these structures and provides clues to how photosynthesis evolved.

Emmanuel Javeau Researchers from the University of Liège in Belgium analyzed fossils collected from rocks at three locations. The oldest site is the approximately 1.75 billion-year-old McDermott Formation in Australia, the other two are the billion-year-old Grassy Bay Formation in Canada and the Bllc6 Formation in the Democratic Republic of Congo. was.

From these rocks, the researchers extracted fossilized cyanobacteria that produce energy through photosynthesis. “They're so small, less than a millimeter, that you can't see them with the eye,” Java says. She and her colleagues placed the fossils in resin, sliced ​​them into sections 60 to 70 nanometers thick using a diamond-bladed knife, and analyzed their internal structures using an electron microscope.

They discovered that cyanobacteria in Australia and Canada contain thylakoids, membrane-enclosed sacs in which photosynthesis occurs. “These are the oldest fossilized thylakoids that we know of today,” Java says. Previously, the oldest thylakoid fossils were around 550 million years old. “So we delayed the fossil record by 1.2 billion years,” she says.

This is important because not all cyanobacteria have thylakoids and it is unclear when these structures, which make photosynthesis more efficient, first evolved, they said. Kevin Boyce at Stanford University in California. The origins of this diversification can now be traced back at least 1.75 billion years, he says. The oldest fossils of cyanobacteria are about 2 billion years old, but other evidence, such as geochemical signatures, indicate that photosynthesis has been around even longer than that.

It is widely believed that cyanobacteria helped build up oxygen in Earth's atmosphere 2.4 billion years ago. “The idea is that perhaps during this time they invented thylakoids, which increased the amount of oxygen on Earth,” Java says. “Now that we have discovered very old thylakoids and found them preserved in very old rocks, we think we might be able to test this hypothesis even further back in time,” she says. .

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Source: www.newscientist.com

Newly Discovered Fossils Shed Light on Enigmatic Human Lineage in the Levant

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Orthographic view of the static skull, mandible, and parietal bones.Credit: Tel Aviv University

Nesher Ramla homoan ancient hominin group discovered in Israel reveals a complex admixture of Eurasian and African hominins 140,000 years ago, changing perceptions of the origins of Neanderthals.

Researchers have discovered a previously unknown archaic hominin group they named Nesha Ramla. homo” at a recently excavated site in Israel. This group, dating from about 140,000 to 120,000 years ago, is thought to be the last survivor of the Middle Pleistocene. homo. They exhibit a unique blend of Neanderthal and ancient human characteristics and technology.

Neanderthals are thought to have originated and flourished in continental Europe long before modern humans arrived. However, recent evidence suggests a genetic contribution from as yet unknown non-European populations and points to a long and dynamic history of interactions between Eurasian and African hominin populations.

Human interaction in Eurasia and Africa

Here, Israel Hershkovitz, Yossi Zeidner and colleagues present fossil, artifact, and radiometric evidence from the Levantine region of the Middle East that illustrates this complexity. According to Hershkovitz et al., the newly discovered Nesher Ramla homo They exhibit anatomical features that are older than their contemporaneous Eurasian Neanderthals and modern humans, who also lived in the Levant. This discovery indicates that this archaic lineage may represent one of the last surviving populations of the Middle Pleistocene. homo in southwest Asia, Africa, and Europe.

Archaeological context and cultural interaction

In joint research, Zaidner other. We provide archaeological context for the new fossils and report on their associated radiometric dates, artifact assemblages, and the behavioral and environmental insights they provide. Researchers found that Nesher Ramla homo Familiar with technology that was previously known only to a select few homo sapiens And Neanderthals. Taken together, these findings provide archaeological support for close cultural interactions and genetic admixture between different human lineages before 120,000 years ago. This may help explain the different expressions of teeth and skeletal features in later Levantine fossils.

“Interpretation of Nesher Ramla fossils and stone tools will have mixed reactions among paleoanthropologists. Nevertheless, the age of Nesher Ramla materials, the discordant morphological and archaeological similarities , and the site’s location at the crossroads of Africa and Eurasia make this a major discovery,” writes Marta Lahr in an accompanying Perspective.

For more information about this research, see Types of prehistoric humans previously unknown to science.

References:

“Middle Pleistocene Homo from Nesher Ramla, Israel” Israel Hershkovitz, Hilla May, Rachel Salig, Ariel Pokhodzhaev, Dominique Grimaud Hervé, Emiliano Bruner, Cinzia Fornai, Rolf Quam, Juan. Written by Luis Arzuaga, Victoria A. Crenn, and Maria Martinon Torres, José María Bermudez de Castro, Laura Martin Frances, Vivian Soulon, Lou Albesado Ball, Amelie Viale, and Tim Schuler , Giorgio Manzi, Antonio Profico, Fabio Di Vincenzo, Gerhard W. Weber, Yossi Seidner, June 25, 2021, science.
DOI: 10.1126/science.abh3169

“Behavior and culture of Homo during the Middle Pleistocene, 140,000 to 120,000 years ago, and interaction with Homo sapiens” Yossi Seidner, Laura Senty, Marion Prevost, Norbert Mercier, Christophe Farguerre, Gilles Guerin, Hélène Valadas, Mairis Richard, Asmodee Ghaly, Christophe Pécherin, Olivier Tombre, Edwidge Pons-Branch, Naomi Porat, Ruth Shahak Gross, David E. Friesem, Reuven Yeshurun, Zohar Turdjman Yaffe, Amos Frumkin, Gadi Herzlinger, Ravid Eckstein, Maayan Shemar, Oz Valoner, Rachel Salig, Hila May, Israel Hershkovitz, June 25, 2021, science.
DOI: 10.1126/science.abh3020

Source: scitechdaily.com