SEO-Optimized Title: “The Late Ordovician Mass Extinction: How It Laid the Foundation for the Evolution of Early Fish”

Posted on January 13, 2026 by Igor Mitreski

A significant enigma in vertebrate evolution—why numerous major fish lineages appeared suddenly in the fossil record tens of millions of years post their presumed origins—has been linked to the Late Ordovician mass extinction (LOME). This insight comes from a recent analysis conducted by paleontologists at the Okinawa Institute of Science and Technology Graduate University. The study reveals that the LOME, occurring approximately 445 to 443 million years ago, instigated a parallel endemic radiation of jawed and jawless vertebrates (gnathostomes) within isolated refugia, ultimately reshaping the early narrative of fishes and their relatives.

Reconstruction of Sacabambaspis jamvieri, an armored jawless fish from the Ordovician period. Image credit: OIST Kaori Seragaki

Most vertebrate lineages initially documented in the mid-Paleozoic emerged significantly after the Cambrian origin and Ordovician invertebrate biodiversity. This temporal gap is often attributed to inadequate sampling and lengthy ghost lineages.

However, paleontologists Kazuhei Hagiwara and Lauren Saran from the Okinawa Institute of Science and Technology Graduate University propose that the LOME may have fundamentally transformed the vertebrate ecosystem.

Utilizing a newly compiled global database of Paleozoic vertebrate occurrences, biogeography, and ecosystems, they identified that this mass extinction coincided with the extinction of stylostome conodonts (extinct marine jawless vertebrates) and the decline of early gnathostomes and pelagic invertebrates.

In the aftermath, the post-extinction ecosystems witnessed the initial definitive emergence of most major vertebrate lineages characteristic of the Paleozoic ‘Age of Fish’.

“While the ultimate cause of LOME remains unclear, clear changes before and after the event are evident through the fossil record,” stated Professor Saran.

“We have assimilated 200 years of Late Ordovician and Early Silurian paleontology and created a novel database of fossil records that will assist in reconstructing the refugia ecosystem,” Dr. Hagiwara elaborated.

“This enables us to quantify genus-level diversity from this era and illustrate how LOME directly contributed to a significant increase in gnathostome biodiversity.”

LOME transpired in two pulses during a period marked by global temperature fluctuations, alterations in ocean chemistry—including essential trace elements—sudden polar glaciation, and fluctuations in sea levels.

These transformations severely impacted marine ecosystems, creating post-extinction ‘gaps’ with reduced biodiversity that extended until the early Silurian period.

The researchers confirmed a previously suggested gap in vertebrate diversity known as the Thalimar gap.

Throughout this time, terrestrial richness remained low, and the surviving fauna consisted largely of isolated microfossils.

The recovery was gradual, with the Silurian period encompassing a 23-million-year recovery phase during which vertebrate lineages diversified intermittently.

Silurian gnathostome lineages displayed gradual diversification during an early phase when global biodiversity was notably low.

Early jawed vertebrates appear to have evolved in isolation rather than rapidly dispersing into ancient oceans.

The researchers noted that gnathostomes exhibited high levels of endemism from the outset of the Silurian period, with diversification occurring primarily in certain long-term extinction reserves.

One such refuge is southern China, where the earliest conclusive evidence of jaws is present in the fossil record.

These primitive jawed vertebrates remained geographically restricted for millions of years.

Turnover and recovery following LOME paralleled climatic fluctuations similar to those at the end of the Devonian mass extinction, including prolonged epochs of low diversity and delayed dominance of jawed fishes.

“For the first time, we discovered the entire body fossil of a jawed fish directly related to modern sharks in what is now southern China,” Dr. Hagiwara noted.

“They remained concentrated in these stable refugia for millions of years until they evolved the capability to migrate across open oceans to new ecosystems.”

“By integrating location, morphology, ecology, and biodiversity, we can finally understand how early vertebrate ecosystems restructured themselves after significant environmental disruptions,” Professor Saran added.

“This study elucidates why jaws evolved, why jawed vertebrates ultimately became widespread, and how modern marine life originated from these survivors rather than earlier forms like conodonts and trilobites.”

For more information, refer to the study published on January 9th in Scientific Progress.

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Kazuhei Hagiwara & Lauren Saran. 2026. The mass extinction that initiated the irradiation of jawed vertebrates and their jawless relatives (gnathostomes). Scientific Progress 12(2); doi: 10.1126/sciadv.aeb2297

Source: www.sci.news

Extinction Made Headlines in 2025, But Failed to Meet Expectations

Posted on December 12, 2025 by

Colossal’s so-called dire wolf

huge life science

Colossal Biosciences, which advertises itself as “the world’s first and only anti-extinction company,” has garnered significant attention this year, although much of the buzz is detached from the truth.

Initially, the company made headlines with its woolly rat, allegedly “engineered to express several mammoth-like traits.” Victoria Herridge from the University of Sheffield observed that the long-haired mice featured in media reports were not created through genetic modifications drawing from mammoth DNA; rather, geneticists have been producing long-haired mice for years. Mice with mammoth-related genetic alterations showed less resemblance to their extinct counterparts.

Subsequently, major news broke with a corporate press release. Colossal announced the “resurrection” of the direwolf (Aenocyon Dylas), a wolf-like creature that was extinct in the Americas approximately 10,000 years ago. However, Colossal’s actual achievement was making 20 minor adjustments to the genome of gray wolf cells (Canis lupus), only 15 of which were informed by the direwolf’s genome, resulting in the cloning of these modified cells to create three wolf pups.

With millions of genetic differences existing between both species, this step merely nudges gray wolves closer to their ancient relatives. It remains an incredibly long journey to achieve anything resembling an exact genetic replica akin to something from Jurassic Park.

Most media outlets reported on the de-extinction claims without skepticism. New Scientist had the headline: “No, the direwolf is not coming back from extinction.”

Colossal’s Chief Scientist, Beth Shapiro, tried to provide justification based on appearance, stating “We use the concept of morphological species and assert that if it looks like this animal, then it is that animal,” as reported by New Scientist on April 7th.

Despite genetic distinctions, it remains uncertain if cloned gray wolves truly resemble the extinct species. The International Union for Conservation of Nature’s canine expert group stated on April 18, “There is no evidence that genetically modified animals are phenotypically different from gray wolves or similar to dire wolves.”

In a subsequent interview with New Scientist, Shapiro appeared to acknowledge this fact. “It’s impossible to resurrect the same species that existed. Our animal is a cloned gray wolf with 20 edits,” she clarified. “And we’ve been transparent about that from the start. People informally refer to them as direwolves, which understandably frustrates some.”

Following our article that cited Shapiro, Colossal reaffirmed its assertions: “With these edits, we are reviving the direwolf.”

However, apart from those directly involved with Colossal, New Scientist reports that no biologist believes the direwolf has truly returned. “As far as I’m aware, there’s no justification for labeling these genetically altered gray wolves as direwolves,” claims Vincent Lynch from the University at Buffalo, New York. “At least within my network, there is complete consensus that these assertions are unfounded.”

Lynch suspects that many people, outside the realm of biology, might accept these claims due to ongoing media portrayals that frequently present them as fact. He and others are concerned that the notion of reviving extinct species could detract from crucial efforts to protect endangered animals.

“People have genuinely bought into these assertions, but forecasting their impact on long-term conservation strategies is quite challenging,” Herridge stated.

In July, Colossal announced intentions to resurrect the flightless moa bird from New Zealand. Critics, including Nick Lawrence, a professor at the University of Otago in New Zealand, remarked that the company might only be able to create something resembling a “Frankenmore” rather than an authentic extinct bird.

Meanwhile, Lawrence, Lynch, Herridge, and other notable critics of Colossal’s de-extinction endeavors have become targets of an enigmatic smear campaign, a situation the company denies involvement in. Anonymous online posts and videos have surfaced, criticizing their expertise and credentials. Lynch stated this is excessive. New Scientist reported on July 31 about an additional attack on Lawrence, published on September 5, while Herridge encountered yet another dubious article.

Even critics concur that Colossal is making impressive progress. However, Richard Grenier, a professor at the University of Oxford, insists that discussions surrounding the de-extinction of endangered species are distractions from the more significant challenge posed by humanity’s growing capability to alter animal genomes on a large scale. “We will need to have another societal conversation regarding what we find acceptable and what we don’t,” he remarked.

“There might be specific instances where such technology could assist in the genetic rescue of bottleneck populations, adding some conservation benefit, but it will always be highly specialized and costly.”

topic:

extinction/
2025 News Review

Source: www.newscientist.com

Climate Change Significantly Contributed to the Extinction of Homo floresiensis

Posted on December 9, 2025 by

Homo floresiensis A recent study indicates that Liang Bua, the cave where this diminutive hominin species resided for approximately 140,000 years, was deserted during a significant drought between 61,000 and 55,000 years ago.

Reconstruction of Homo floresiensis. Image credit: Elizabeth Danes.

Homo floresiensis was first identified in 2003 in Liang Bua, Flores Island, Indonesia.

This species, often referred to as hobbits due to their small size, challenged prevailing theories regarding human evolution.

It vanished from the fossil record around 50,000 years ago, but the reasons for its disappearance are still unclear.

“In 2003, excavations in the Liangbua rock trench unveiled the skeletons of a previously unknown small hominid species, Homo floresiensis,” stated Emeritus Professor Mike Gagan and colleagues from the University of Wollongong.

“Originally, the period of occupation was estimated to be between 95,000 and 12,000 years ago, suggesting the possibility of interaction with early modern humans (Homo sapiens), who inhabited islands in Southeast Asia and were contributing to species extinctions.”

“However, following a revision of the stratigraphy and chronology at this site, all Homo floresiensis human bones are now believed to be approximately 100,000 to 60,000 years old.”

“Associated stone artifacts and megafaunal assemblages typically suggest that Homo floresiensis went extinct around 50,000 years ago.”

“The revised timeline indicates they disappeared from the record around 46,000 years ago, coinciding with the arrival of modern humans at Liang Bua, and there was a significant shift in the types of materials used for making stone tools.”

In the study, the authors integrated chemical records from cave stalagmites with isotope data from the fossilized teeth of a pygmy elephant species, Stegodon florensis insularis, which Homo floresiensis hunted.

The findings reveal a large-scale drying trend that commenced around 76,000 years ago and peaked in severe droughts between 61,000 and 55,000 years ago, near the time when the species went extinct.

Prolonged drought and heightened competition for resources may have led to their abandonment of Liang Bua and, ultimately, their extinction.

“At that time, the ecosystem surrounding Liang Bua experienced significant drying. Homo floresiensis vanished,” remarked the lead author of the study, Emeritus Professor Mike Gagan from the University of Wollongong.

“The summer rains caused the riverbed to become dry seasonally, placing stress on both the hobbits and their prey.”

The population of pygmy elephants saw a drastic decline around 61,000 years ago, signaling the loss of a crucial food source for the hobbits.

“Surface freshwater, along with Stegodon and Homo floresiensis, all diminished simultaneously, showcasing the compounded effects of ecological stress,” stated Dr. Gerd van den Bergh from the University of Wollongong.

“Competition for the scarce water and food likely forced the hobbits to vacate Liang Bua.”

“Meanwhile, the fossils of Homo floresiensis predate the earliest evidence of modern humans on Flores, Homo sapiens, who were traversing the Indonesian archipelago when the hobbits went extinct.”

“It’s possible that the hobbits encountered modern humans while migrating in search of water and food,” Professor Gagan noted.

“In that context, climate change may have set the stage for their eventual extinction.”

The study was published in the journal Communication Earth and Environment.

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MK Gagan et al. 2025. The onset of summer dryness and forest decline of Homo floresiensis at Liang Bua 61,000 years ago. Communication Earth and Environment 6,992; doi: 10.1038/s43247-025-02961-3

Source: www.sci.news

Could Humans Face Extinction in Precisely 314 Years?

Posted on October 17, 2025 by

Feedback is New Scientist A well-known figure who observes the latest news in science and technology with a critical eye. To share feedback about topics you believe may interest our readers, please contact us at feedback@newscientist.com.

Our Expiry Date

Unfortunately, we have some bad news. Humanity’s time is marked; experts predict our extinction by 2339, leaving us only a few centuries (as of now).

News Editor Jacob Aaron presented this startling information. A paper not yet peer-reviewed was shared on the social science preprint server SocArXiv. In their work, demographers David Swanson and Jeff Tayman discuss how the human population could decline from the current 8.1 billion to zero.

Their reasoning is straightforward: “Considering the decrease in birth rates from 2019 to 2024 and applying probabilistic forecasting methods, by 2139, the world’s population will fall between 1.55 billion and 1.81 billion… By 2339, humanity will be extinct,” they assert.

Swanson and Tayman highlight that this extinction timeline is “only 314 years away.” One might think the estimate could have been rounded to 300 to incorporate some necessary uncertainty in the predictions, but the confidence displayed is noteworthy.

This may seem evident, but we cannot base projections for the next three centuries on just five years of data — especially from 2019 to 2024, a period marked by significant global events that likely impacted birth rates.

They employed three different methodologies: the Cohort Component Method, the Hamilton-Perry Method, and even the notable Espenshade-Tiemann Method. Despite this, the prediction remains flawed. However, it’s likely our audience has already deduced this.

For a moment, we questioned if the paper was intended as satire, aiming to mislead unsuspecting science journalists into reckless reporting. However, this seems unlikely as Mr. Swanson shared it at a conference in September. Following his presentation, “a robust discussion unfolded.“Oh, I can’t believe I was heading straight for that wall.

This might hint at a precursor to a new belief system, positioning the apocalypse conveniently three centuries away to avoid embarrassment if it doesn’t come to pass.

Oh, No More

The feedback reveals that US President Donald Trump referred to climate change as “a scam, deeming renewable energy sources like wind power as “pathetic.”

This came in the wake of a government report published in July, generated by “independent researchers,” attempting to justify ceasing climate change mitigation efforts. Carbon Brief reviewed the report and identified over 100 misleading statements. Across the pond, the British Conservative Party has pledged to repeal climate change legislation upon regaining power.

The feedback notes that renewable energy has surpassed coal to become the leading source of electricity by mid-2025, which doesn’t seem particularly pathetic. Meanwhile, we’re reminded of that memorable scene from Monty Python and the Holy Grail, where monks beat their heads in a rhythmic fashion. We can only assume that these individuals read Swanson and Tayman’s paper and concluded that 2339 was too far off.

A Simple Thank You

One of the hallmarks of being an excellent researcher is to explore questions that others haven’t considered. Consequently, a study was published in the journal Socius in September: “‘This Task Would Have Been Impossible‘… A study examining the length of acknowledgments in sociology books.” Yes, that’s correct. This is an entire sociology paper dedicated to the acknowledgments section of sociology literature.

The first takeaway, as noted by the authors, is that they are not the first to pose this question. Back in 1972, Kenneth Henry Mackintosh published a study titled Approval Patterns in Sociology. When I searched for feedback online, I was disappointed to find that it was over 300 pages long and, even if the table of contents was accurate, it lacked an acknowledgments section.

What of the new research? The researchers evaluated 411 books written by 317 sociologists and examined the acknowledgments (excluding 7 percent for rudeness). A significant statistical trend revealed that female authors wrote longer acknowledgments than their male counterparts.

Similarly, books released by university presses contained longer acknowledgments compared to those from other publishers. It remains unclear whether this means they were thanking more individuals or simply elaborating more extensively.

Naturally, I was curious about the acknowledgments section of this very paper, so I scrolled down. We were pleased to see it consisted of 218 words and included a heartfelt mention of “steadfast love and support.”

Then, we discovered it wasn’t entirely original. Co-author Jeff Lockhart listed the paper on Bluesky, and another researcher quipped:I love that the paper itself has a lengthy acknowledgments section. In response, Lockhart remarked, “we felt it was necessary.”

I would like to acknowledge the cats who prevented me from stepping on my laptop keyboard while writing this article.

Have a story for feedback?

You can send your article to Feedback at feedback@newscientist.com. Please include your home address. You can find this week’s and past feedback on our website.

Source: www.newscientist.com

Chris Packham: “This Isn’t Just an Extinction Event—It’s Extinction Itself.”

Posted on October 2, 2025 by Igor Mitreski

Wildlife broadcaster Chris Packham developed a deep connection with nature long before he could articulate it. As a child in his parents’ modest Southampton backyard, he became captivated by tadpoles, snails, and ladybugs. His interests quickly flourished, transforming his bedroom into a sanctuary of jars and tanks, with the garden evolving into a habitat for foxes and kestrels.

Packham attributes part of his intense curiosity to autism, which he believes enhances his pattern-finding abilities while also necessitating refuge from overwhelming social interactions. Unreservedly vocal both on-screen and off, Packham champions environmental issues and animal rights, spearheading campaigns like one aiming to cease game shooting and industrial agriculture. These outspoken views have not been without consequences; in 2019, threats against him escalated to the point where a dead crow and a fox were left hanging from his gate.

Yet these acts of violence only fortify his resolve to advocate for the natural world. In a conversation with New Scientist, he shared insights about his ongoing campaign against fossil fuel advertising in the UK, his upcoming evolution television series, and strategies for fostering a sustainable future on Earth.

Thomas Luton: Your connection with nature is evident every time I watch BBC’s Spring Watch. Does your autism you have help forge this bond?

Chris Packham: My fascination with nature comes from my meticulous observation and rapid memorization skills, allowing me to identify behaviors and anatomical patterns. I found a comfort zone in the natural world, free from peer judgment. My father, a marine engineer, and my mother, the Attorney General, didn’t directly fuel my interest, but they offered support.

Walking through the forest is one thing people who don’t need to overconsume can do

Kevin Britland / Alamy Stock Photo

As a child, my room was filled with living specimens. However, everything changed when I turned 12 and received a pair of binoculars from my dad. My passion shifted from maintaining creatures to observing them in their natural habitats.

I had an intense interest in natural history, often jumping from one species to another. While it may now be termed “intense interest,” I prefer the term “obsession.” The greater your ability to concentrate on specific tasks, the easier it is to push aside distractions and delve deep into the subject matter, which becomes a driving force behind your curiosity.

Those are remarkable abilities. However, being neurodivergent has its challenges. How might you encourage others to consider how a neurodivergent individual with autism perceives the world?

It’s essential to focus not just on challenges but also on the opportunities and strengths that come with neurodiversity. As a child, I felt drawn to the forest to engage with the wonders I desired to see and capture. In truth, I found solace there, free from judgment.

I became completely immersed in the experience. While most can identify trees by looking at their shape, leaves, or bark, I can recognize them by the sound of raindrops on their leaves when I close my eyes. It’s not an extraordinary skill—anyone can learn it—but it reflects how deeply I wish to engage with the natural world.

You’ve dedicated a significant portion of your life to environmental protection. Why do you think you’ve faced backlash as an activist?

Like many, I’m asking essential sections of society to reassess their opinions and habits. Humans are remarkable creatures—intelligent, adaptable, and innovative—yet we often struggle to change our minds.

We burn the natural resources of the planet

Jim West / Alamy Stock Photo

However, it’s evident that if we don’t change our philosophies and practices, we will continue to dive deeper into crisis. There are opportunities to address these issues, and it’s vital we seize them while we can. Unfortunately, some segments of society resist this change, and that small minority can react aggressively.

Why do you think you’re confronted with such violence?

I genuinely don’t let it affect me. I’m a determined individual; if I believe in the cause, I won’t be deterred by threats. I don’t engage in a fight because I expect to win; I choose my battles based on what I believe is right. Winning isn’t about crossing the finish line; it’s about perseverance.

Currently, it can be quite challenging to unite activists, campaigners, and protestors in solidarity.

How can this be achieved?

In the UK, public protest is hindered by an unjust legal landscape. Sometimes, merely wearing a T-shirt or holding a sign can lead to arrest. We have to confront the ongoing atrocities related to environmental legislation, not just locally but especially regarding protections elsewhere in the world.

Nonetheless, I remain optimistic. Humanity possesses incredible tools, technologies, and capabilities to adapt to the challenges we’ve created. The key is to harness and deploy these resources effectively and swiftly.

Recently, you launched a petition to end fossil fuel advertising and sponsorships in the UK. Is this a significant hurdle to climate action?

In the UK, fossil fuel companies may not invest heavily in advertising, yet they cleverly target their efforts towards decision-makers and influential figures. This manipulation breeds skepticism.

Moreover, billions are funneled into sports sponsorships by these companies, subtly embedding themselves into daily life, thereby normalizing their practices.

Protesters fighting Shell’s British Cycling sponsorship

Andrea Domeniconi/Alamy Live News

Such sponsorships should not normalize corporations that harm our planet. The juxtaposition of cycling—an activity promoting health and reducing carbon emissions—with Shell’s sponsorship is nothing short of absurd. Additionally, allowing fossil fuel companies to sponsor institutions like the Science Museum and British Museum is unacceptable.

What does a sustainable future entail for you?

While technology presents challenges in forecasting, what I need is a shift in mindset. The prevalent focus on economic growth must be abandoned, as such growth often comes at the expense of our planet’s resources. Carefully managing these limited resources is essential for our future.

“
I ask important parts of the population to change their minds and habits
“

People need to reevaluate their desires. Does consuming more truly bring happiness? What genuinely enriches our lives—whether it’s nature, art, music, or dance—does not necessitate piling up possessions.

What additional changes are essential beyond mindset? Should we consider reducing population growth as part of achieving sustainability?

When discussing overpopulation, precision is essential. More people typically mean more consumption, but we must consider who is consuming. In many rapidly growing regions, consumption levels remain low.

If everyone consumed resources at the same rate as individuals in the US, we would require the resources of five planets to uphold that demand. Given the vast disparities in resource availability, equality is crucial for addressing climate change.

One of the most disappointing aspects of the Climate Summit discussions is the reluctance to subsidize poorer nations, which bear the brunt of climate change, due to selfish interests.

Shifting topics, you recently completed filming a BBC series on evolution, set to debut next year. How can humans benefit from understanding their place in the lengthy history of evolution?

We must first recognize how fortunate we are to exist. Mutations are random occurrences, and the conditions that foster success can be incredibly rare. The chances of human life evolving were slim, often hinging on serendipity.

Moreover, evolution offers critical insight into the harm humans inflict on nature. While examining historical extinction events, it’s important to remember that they aren’t always catastrophic for all life forms. For instance, while the extinction of dinosaurs presented hurdles for them, it opened up numerous ecological niches for mammals to thrive.

Today, we aren’t merely observing extinction events; we’re actively causing them. We must use accurate language to address this issue. No matter the harm inflicted on our planet, the resilience of life suggests it will endure, possibly evolving into forms more beautiful than before.

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Source: www.newscientist.com

A Fascinating Exploration of Neanderthal Extinction: A True Literary Gem

Posted on September 26, 2025 by Igor Mitreski

Ludovic Slimak contributed to revealing the remains of Thorin, a Neanderthal

Laure Metz

The Last Neanderthal
Ludovic Slimak (translated by Andrew Brown) (Polity Press (UK, September 26, US, November 24))

Chance findings of Neanderthal skeletons, hardened soot, and small arrowhead tools beneath leaves at the French Grotte Mandrin have reshaped not only our perception of Neanderthals but also our understanding of early Homo sapiens migrations into Europe.

More intriguingly, this cave has unveiled insights about the initial interactions between the two groups and the reasons behind the success of one species and the extinction of another. This pivotal issue is explored in The Last Neanderthal: Understanding How Humans Die, a new work by Ludovic Slimak, a paleontologist from the University of Toulouse who spearheaded the excavations at Grotte Mandrin.

The narrative focuses on Thorin, a Neanderthal fossil unearthed in 2015 at the cave’s entrance, which revealed five teeth during the excavation. The delicate recovery of this singular discovery required painstaking care, extracting each grain of sand with tweezers over seven years to uncover fragments of his skull and hand.

This investigation led to a riveting quest that spanned years, employing various dating methods that initially yielded starkly conflicting timelines for Thorin’s existence. Ultimately, it was determined that the fossils date between 42,000 and 50,000 years ago. The last known Neanderthal population went extinct around 40,000 years ago . Remarkably, Thorin’s genome was sequenced, revealing a previously unknown lineage that diverged from the primary Neanderthal population more than 50,000 years ago and later experienced extreme isolation.

The Last Neanderthal is a deeply introspective and philosophical work, evoking a vivid sense of what it would have meant to explore Thorin’s existence and the myriad groups that inhabited the cave over millennia. Slimak notes that the unique scent of Grotte Mandrin originates from ancient fire soot preserved within the calcite layers of its walls, forming a distinctive ‘barcode’. This barcode can be accurately dated, providing timelines for various occupations and indicating that Homo sapiens arrived just six months after the Neanderthals vacated the cave. The book reveals that Thorin appears unexpectedly, causing Slimak to express his astonishment, stating, “I did not expect to find a Neanderthal body lying by the roadside, walking through the forest like that. It’s astonishing.”

The jaw of Thorin, a Neanderthal fossil unearthed in 2015

Xavier Muth

This prompts further contemplation about the reasons behind the Neanderthals’ extinction. Although much discussion centers around their decline due to competition with Homo sapiens or climate shifts caused by volcanic eruptions and magnetic field reversals, Slimak offers a fresh perspective. He highlights that the evidence found at Grotte Mandrin points to a layer of small triangular stone points used as arrows by the earliest Homo sapiens, who arrived around 55,000 years ago.

These artifacts bear a striking resemblance to those produced by Homo sapiens at the Ksar Akil site in Lebanon, located nearly 4,000 km away and dating to a similar timeframe. This suggests that these early humans exhibited a far more sophisticated method of sustaining and standardizing practices across extensive social networks, leading Slimak to conclude they had a much more effective “way of life” compared to the Neanderthals, who lived in smaller, isolated groups lacking such consistency.

While one might envision a dramatic battle between Homo sapiens and Neanderthals, the reality was notably different. Slimak draws parallels with the collapse of numerous indigenous communities in post-colonial regions globally, asserting that Neanderthal groups gradually disintegrated when faced with others who possessed a more efficient existence. “The demise of humans reflects the disintegration of their worldview… not through overt violence, but through whispers,” he observes.

“
The bones were painstakingly excavated using tweezers to remove one grain of sand at a time.
“

Although it is profoundly melancholic to ponder, immersing oneself in the realm of these vanished beings through The Last Neanderthal is a unique privilege.

Topic:

Ancient Humans/
Book Review

Source: www.newscientist.com

Study Reveals How the Extinction of Non-Bird Dinosaurs Transformed the Landscape

Posted on September 17, 2025 by Igor Mitreski

Recent studies indicate that dinosaurs acted as ecosystem engineers, fostering habitat openness during the late Cretaceous period. Their extinction around 66 million years ago likely triggered a significant reorganization of ecosystem structures, profoundly affecting rivers. The emergence of dense forests helped stabilize sediments and created a wide, meandering river surrounding the water.

Dinosaurs functioned as ecosystem engineers, regulating forest growth. Their abrupt extinction resulted in extensive ecological shifts, as illustrated in these artistic renderings. Image credit: Julius Csotonyi.

“When considering how life and the environment evolve over time, it’s typically viewed as climate-driven, causing specific effects on living beings. Alternatively, geographic shifts, like rising mountains, also have a notable impact,” explained Luke Weaver, a paleontologist at the University of Michigan.

“It’s uncommon for life to play a crucial role in altering climate and landscape; the influence isn’t solely one-directional.”

The extinction of dinosaurs followed the impact of a massive asteroid on the Yucatan Peninsula approximately 66 million years ago.

Researchers investigating asteroid evidence discovered that the geological layer above the fallout fragments differed significantly from the underlying rock.

Dr. Weaver and his team began examining this abrupt geological transformation within the Williston Basin, which encompasses the Bighorn Basin across eastern Montana, western North Dakota, and northern Wyoming.

“During my review of previous research, I focused on the Fort Union Formation,” Dr. Weaver mentioned.

“This formation, laid down post-dinosaur extinction, appears to consist of layered rocks in various hues.

“Initially thought to be pond sediments resulting from sea level rise, these formations presented an intriguing contrast to the layer beneath, characterized by poorly developed soils that recall features found along flood plains.”

Researchers then hypothesized a link between these geological alterations and the mass extinction event of dinosaurs, commonly referred to as the end-Cretaceous mass extinction.

They further explored the environments represented by the diverse rock formations.

“Our findings indicated that the striped layers were not sediment from ponds,” Dr. Weaver stated.

“Instead, these are point bar deposits, or sediments from the inner curves of large river meanders.”

“Rather than reflecting a tranquil setting, what we uncovered was a highly dynamic environment within those meandering flows.”

Substantial river sediments are framed by layers primarily comprising lignite, a low-grade coal formed from organic material.

Researchers suggested these formed due to less frequent river activity, attributable to the stabilizing effects of dense forests.

“By stabilizing rivers, these forests curtailed the supply of clay, silt, and sand deep into the floodplain, resulting in an accumulation of mainly organic debris,” Dr. Weaver explained.

What evidence will ascertain whether changes occurred right after the mass extinction?

Fine layers rich in iridium are typically found only from cosmic events.

However, the asteroid impact introduced a mix of elements that settled in thin layers across the globe.

This iridium-rich sediment layer, which defines the Cretaceous-Paleogene boundary, contains about three orders of magnitude more iridium than standard sediments and is recognized as an iridium anomaly.

The researchers subsequently focused on areas of the Bighorn Basin where the boundary was absent.

By analyzing geological shifts between the dinosaur-rich layers and those containing early mammals, they sampled narrow bands of red clay about 1 cm wide.

“These iridium anomalies were perfectly situated at the interface between the two differing geological layers,” Dr. Weaver noted.

“This discovery led us to believe that this phenomenon wasn’t isolated to the Williston Basin; it likely applies across many regions in western North America.”

However, questions linger regarding the reasons for the substantial geological transformations observed before and after the dinosaurs’ extinction.

Later, the team came upon discussions regarding how modern animals, such as elephants, impact their ecosystems.

“This was the moment of clarity that connected all the dots,” Dr. Weaver remarked.

“Dinosaurs were enormous; they must have substantially influenced the vegetation.”

Paleontologists have posited that dinosaurs played a crucial role in facilitating forest growth, trapping sediments, and shaping river structures.

“For me, the most thrilling aspect of our research is the evidence that dinosaurs may have directly influenced their ecosystems,” said Dr. Courtney Splain, a researcher at the University of Florida.

“Notably, the impacts of their extinction may be observed not merely through the disappearance of fossils in the geological record, but also through evident changes in the sediment itself.”

Survey results were published this week in the journal Communication Earth and the Environment.

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ln weaver et al. 2025. Dinosaur extinction can explain the change in continental facies at the Cretaceous-Paleogene boundary. Commune Earth Environment 6, 712; doi:10.1038/s43247-025-02673-8

Source: www.sci.news

The Extinction of a Dinosaur: A Dramatic Transformation of Earth’s Landscape

Posted on September 15, 2025 by Igor Mitreski

Large dinosaurs such as Titanosaurus significantly influenced their ecosystems

Christian Jegou/Science Photography Library

The extinction of dinosaurs had profound consequences for Earth, leading to significant alterations in the planet’s landscapes, including shifts in river systems.

There is a clear distinction between various rock formations in North America before and after the end of the dinosaurs during the Cretaceous-Paleogene (K-PG) extinction event approximately 66 million years ago, triggered by the Chicxulub asteroid impact in the Yucatan Peninsula.

For example, the Green Gray Mudstone, recognized as the Hell Creek Formation from the dinosaur period, transitions into the more vivid pajama-striped layers of the Fort Union Formation, which hosts many lignite-rich charcoals from plant material that surfaced with the rise of mammals.

This transition was initially attributed to the direct impacts of asteroid strikes, such as increased rainfall. However, Luke Weaver from the University of Michigan and his team propose another explanation.

They examined floodplain areas in the western United States, revealing abrupt geological changes around the K-PG boundary, particularly in the Williston Basin, stretching across parts of Wyoming, Montana, and the Dakotas.

The multifaceted colorful layers from the Post-dinosaur period are believed to be deposits formed by rising water levels, creating temporary ponds. However, Weaver and his colleagues did not find supporting literature on water level changes during this era.

“There’s no evidence of extremely high water tables or particularly wet conditions,” he says. While there was an intrusion of seawater inland, the nearest instance occurred at least 300,000 years after the K-PG boundary.

Weaver’s team argues that significant sandstone layers formed post-K-PG boundary are indicative of large, stable rivers, known as Point Bar deposits, instead of temporary pond deposits. These layers can exceed 10 meters in thickness, reflecting the stability of these rivers.

Researchers attribute these findings to the extinction of dinosaurs. They propose that, like today’s large herbivores, dinosaurs were ecological engineers, disrupting vegetation, trampling, and grazing seedlings, inhibiting new plant growth.

“These creatures were colossal compared to modern fauna,” Weaver notes. For instance, while a contemporary elephant weighs around 5,000 kilograms, a Triceratops could weigh at least double that.

As they moved through and destroyed vegetation, the rivers would have flooded periodically instead of winding through forests. This change ultimately led to the expansion of marshy mudstone, according to Weaver. Once the dinosaurs vanished, tree roots stabilized the sediments, allowing water to flow through a meandering riverbed, thus creating point bars.

“This illustrates a landscape where biology plays a crucial role,” Weaver observes. Animals, he argues, significantly modify their environments, much like humans have drastically altered Earth’s landscapes.

Christopher Doughty from Northern Arizona University believes this perspective better explains the observed geological transformations than earlier theories. “In contemporary studies where large animals are removed from ecosystems, tree cover significantly increases,” he mentions. “With the extinction of dinosaurs, there were no longer large animals capable of uprooting trees. This led to a decrease in herbivory and reduced the disturbance of seedlings giving rise to robust tree growth.”

However, Cat Schroder from the University of New Mexico remains skeptical. “While there seems to be a correlation between large dinosaurs and open nutritional landscapes, causality hasn’t been established yet,” she says. “Forests thrived before, during, and after the age of dinosaurs.”

Doughty is using isotopic analysis of fossil leaves to investigate how forest structures have shifted since the dinosaurs went extinct.

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Source: www.newscientist.com

Insights from the Thylacine Genome Reveal Reasons for Its Extinction

Posted on August 27, 2025 by Igor Mitreski

Thylacines were once found throughout Australia and New Guinea

Robert Nickelsberg/Getty Images

SEI 263374247 — Thylacines were once found throughout Australia and New Guinea

Robert Nickelsberg/Getty Images

The extinction of crucial genes over the millennia since humans arrived in Australia may have made the thylacine more prone to extinction.

The thylacine, also known as the Tasmanian tiger (Thylacinus cynocephalus), was the last remaining member of a marsupial family called Thylacinidae, which once thrived in Australia and New Guinea.

It became extinct on mainland Australia around 2000 years ago, primarily due to human hunting and competition with dingoes. After European settlers arrived in Tasmania, the animal was targeted by farmers and government bounties, leading to the last of its kind dying in 1936 at Hobart Zoo.

Nagarjun Vijay and Buddha Bhashan Gilish Salv from the Institute of Science and Education in Bhopal, India, grew fascinated by the Tasmanian tiger’s genome while studying that of the Bengal tiger (Panthera tigris tigris).

“We noticed some parallels between the extinction of thylacines and our own tiger,” Vijay notes. “There’s a significant push to protect Indian tigers.”

The duo theorized that hypercarnivores like the Bengal and Tasmanian tigers may have lost vital genes through their evolutionary journey in response to environmental shifts and emerging diseases.

They examined genetic data previously obtained from thylacine specimens and compared these to the genome of the Tasmanian devil, a close relative (Sarcophilus harrisii), along with other marsupials.

Unlike nearly all other marsupials, including the Tasmanian devil, the thylacine has lost at least four crucial genes: SAMD9L, HSD17B13, CUZD1, and VWA7.

Vijay found it surprising that this genetic loss did not occur after Tasmania’s populace was isolated due to rising sea levels roughly 10,000 years ago.

This genetic loss may have been beneficial under certain historical conditions, but can hinder species health by diminishing antiviral defense, metabolic functions, lactation, as well as increasing susceptibility to cancer and pancreatitis.

Thylacines lost SAMD9L, CUZD1, and VWA7 at least 6 million years ago, coinciding with a significant climatic transition when species sizes increased dramatically, resulting in an oversaturation of carnivores entirely dependent on meat.

“The overarching narrative is that much of the human influence, or artificial changes, has perpetually shaped the extinction of thylacines,” Vijay states. “We speculated that there would be lost genes linked to disease, and that’s exactly what we uncovered.”

Timothy Churchill from the University of New South Wales in Sydney emphasizes that climate change over the course of human history has indeed led to a drastic decrease in genetic diversity among thylacines. He believes that the genetic losses identified in the new study may have rendered the Tasmanian tigers more vulnerable to illnesses, though confirming this requires additional research.

“It’s one of those species that truly survived against the odds for an extended period in that niche,” Churchill explains. “But once dingo-like canids arrived, it was the beginning of the end on the mainland. Then, of course, after creating adversaries in Tasmania, it marked their doom.”

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Source: www.newscientist.com

Newly Identified Freshwater Turtle Species Thrived During Dinosaur Extinction

Posted on August 26, 2025 by Igor Mitreski

Paleontologists have introduced a new genus and species of stem cell turtles, based on complete fossil shells discovered in the early Ale Holocene Denver Formation in Colorado.

Reconstruction of Tavachelydra stevensoni in a water environment with logs. Image credit: Andrey Atuchin.

Tavachelydra stevensoni existed in present-day US during the late Ale Holocene, approximately 66-65 million years ago, shortly after the mass extinction event.

The species is part of the Chelydridae family of freshwater turtles, which includes at least seven extinct species and two extant genera.

“The clade of extant Chelydrid turtles (Chelydridae) comprises five species native to the New World,” stated Dr. Tyler Lyson from the Denver Museum of Natural Sciences and his team.

“Though not a varied clade, Chelydrid turtles are commonly found in most North American freshwater ecosystems.”

“The broader group of Chelydrids (i.e., Pan-Chelydridae) is present throughout Laurasia, but their fossil records are notoriously fragmented.”

Fossilized shells and two skulls of Tavachelydra stevensoni were found in the Corral Bluffs survey area in El Paso County, southern Colorado, east of Colorado Springs.

“The straight shell measures nearly 50 cm in length, making Tavachelydra stevensoni one of the larger turtles from the early Ale (Puercan) of the Denver Basin,” remarked the paleontologist.

“Interestingly, two Pan-Chelydrid turtles coexisted during the early Middle Age of this formation: Tavachelydra stevensoni and Denverus middletonii.

“The size difference is significant, with Tavachelydra stevensoni being at least four times larger than Denverus middletonii, which may have reduced competition between the two species in overlapping geographical ranges.”

Although little is known about the paleoenvironment of the single known specimen of Denverus middletonii, the yellow sandstone of fine to medium grain was initially interpreted as channel fill.

In contrast, the two specimens of Tavachelydra stevensoni suggest that they were likely found in ponded waters or sediments, indicating they lived in sediment-rich areas such as overbank deposits.

“While little can be said about the diet of Denverus middletonii due to the lack of skull preservation, the skulls of Tavachelydra stevensoni show large, wide, flat surfaces, likely used to consume hard-shelled organisms such as corals, shelled mollusks, and crabs,” noted the researchers.

“Thus, it seems plausible that Denverus middletonii and Tavachelydra stevensoni occupied distinct ecological niches, with Tavachelydra stevensoni preferring a pond habitat and a durophagous diet.”

“Remarkably, turtle species with a durophagous diet have shown higher survival rates during mass extinction events compared to those with softer diets.”

In addition to the presumed dietary habits of Tavachelydra stevensoni, other common reptiles from the same sedimentary formation include the button-toothed crocodile Cf. Wangonacosuchus and Baenid turtles such as Paratabena nerrellum, Succersies gilberti, and Cedrobaena putrius.

“This indicates that durophagy was a significant life history trait for the earliest Ale-Holocene freshwater vertebrates in North America.”

The discovery of Tavachelydra stevensoni is detailed in a paper published in the Swiss Journal of Palaeontology.

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TR Lyson et al. 2025. New pan-chlydrid turtle, Tavachelydra stevensoni gen. et sp. from the Coral Bluffs area, Lower Aleapione (early Danian, Puercan), Denver Basin, Colorado. Swiss J Palaeontol 144, 46; doi:10.1186/s13358-025-00375-4

Source: www.sci.news

Fossils from Tanzania and Zambia Illuminate the Permian Mass Extinction

Posted on August 12, 2025 by Igor Mitreski

Paleontologists have discovered a variety of animals, including saber-toothed predators, burrowing foragers, and large salamander-like creatures that flourished in southern Pangaea about 252 million years ago, just prior to the mass extinction of the Permian period.

Artistic rendering of an evening about 252 million years ago during the Late Permian Epoch in the Luangwa Basin, Zambia. This scene features several sabertooth Golgonopsians and Dishnodons in the beak. Image credit: Gabriel Ugueto.

“The extinction at the end of the Permian was catastrophic for life on Earth,” stated Professor Christian Saidal of the University of Washington.

“Yet, we do not have a complete understanding of which species managed to survive.

“The fossils we gather in Tanzania and Zambia provide a broader perspective on this remarkable period in our planet’s history.”

All new fossils were uncovered in three basins in southern Africa: the Roof Basin in southern Tanzania, the Luangwa Basin in eastern Zambia, and the Zambezi Central Basin in southern Zambia.

The majority were found by team members during several month-long excavation trips to the region over the past 17 years.

Others were analyzed from specimens excavated decades ago, preserved in museum collections.

“These regions in Zambia and Tanzania are home to incredibly well-preserved fossils from the Permian era,” Professor Saidal remarked.

“They provide us with an unparalleled glimpse into terrestrial life leading up to the mass extinction.”

The Permian period marks the conclusion of what paleontologists term the Paleozoic era.

During this time, animal life, which first emerged in our oceans, began to colonize land and developed complex terrestrial ecosystems.

The Permian epoch saw a diverse range of amphibians and reptile-like creatures inhabit environments ranging from early forests to arid valleys.

The mass extinction at the End-Permian wiped out many of these ecosystems, paving the way for the Mesozoic era, which witnessed the evolution of dinosaurs, the first birds, flowering plants, and mammals.

For decades, scientists relied on the Kalu Basin in South Africa for their best understanding of the Permian, the corresponding extinction, and the onset of the Mesozoic Era, which boasts nearly complete fossil records from before and after that mass extinction.

However, since the 1930s, paleontologists have noted that the fossil records in the Tanzanian and Zambian basins are comparably pristine.

This excavation represents the most extensive analysis of the local fossil record from the period surrounding the Permian mass extinction to date.

“The quantity of specimens found in Zambia and Tanzania is extraordinarily high, and their condition is so exquisite that paleontologists are able to draw species-level comparisons with those in South Africa,” Professor Sidor explained.

“We recognize that there is no better location on the planet to make such precise conclusions and comparisons to glean sufficient detail about this era.”

In the Series of 14 Articles published in Journal of Vertebrate Paleontology, researchers have detailed numerous new species of dicynodonts.

These small, burrowing, reptile-like herbivores first emerged during the Central Permian.

By the time of the mass extinction, the Dishnodons had beak-like snouts featuring two small tusks; many of them dug holes and became the dominant plant-eating animals on land.

The findings also uncover several large saber-toothed predators known as Golgonopsians, along with new species of amphibians, such as large salamanders.

“We can analyze two distinct geographical regions of Pangaea and observe the happenings before and after the Permian extinction,” Professor Saidal concluded.

“This allows us to explore critical questions regarding which species survived and which did not.”

Source: www.sci.news

New Study Illuminates the Rise and Extinction of Giant Sloths

Posted on May 24, 2025 by Igor Mitreski

Currently, only two species of sloths exist, but in the past, numerous species roamed the Earth, including one with a nose resembling a bottle and another akin to the ancestors of modern armadillos. Most of these extinct sloths were too massive to inhabit trees. The largest of them all – a member of the genus Megatherium – reached the size of an Asian bull elephant, weighing around 3.63 tons (8,000 pounds).

The ancient sloths inhabited a variety of environments – trees, mountains, deserts, northern forests, and open savannas – leading to wide differences in size among sloth species. Image credit: Diego Barletta.

“They resembled Grizzly Bears but were five times larger,” noted Dr. Rachel Nalducci, collection manager for vertebrate paleontology at the Florida Museum of Natural History.

In a recent study, Dr. Nalducci and her team examined ancient DNA and compared over 400 fossils from 17 museums to explore how and why extinct sloths achieved such sizes.

The size difference ranges significantly between the massive Megatherium and the more modestly sized Shasta Sloth, which thrived on cacti in the arid regions of North America.

Conversely, the sloths adapted for tree climbing were uniformly small, averaging around 6 kg (14 lbs), with ground-dwelling sloths like them averaging about 79 kg (174 lbs).

Ground sloths had a strong affinity for caves, where their size played a crucial role in finding and creating shelters.

The moderately sized Shasta Sloths ventured into the depths of geological lungs formed by wind and water, creating magnificent canyons.

The larger sloths were not limited to pre-existing caves; using their sizeable claws, the largest known mammalian claws (whether extinct or extant), they could carve out their shelters from bare earth and rock. Evidence of their nests can still be found today, with claw marks adorning the cave walls.

Other factors influencing size variations likely include climate, interspecies interactions, and metabolic rates.

To accurately analyze these factors, a substantial amount of diverse data was required.

The authors integrated fossil shape data with DNA from both living organisms and extinct species to construct sloth lineages dating back over 35 million years.

With this foundation established, they incorporated findings from decades of research about the habitats sloths occupied, their diets, and their behavioral patterns.

Paleontologists maintain a keen interest in the evolution of size, collecting extensive data from numerous museum fossils for their analyses.

Sloth size differences are significantly shaped by the habitats they inhabited, which were also influenced by climate change.

“This research, employing evolutionary models across various scenarios and accounting for all these factors, is a considerable undertaking unlike anything previously attempted,” remarked Dr. Nalducci.

The sloth lineage witnessed dramatic life-altering changes as Earth’s climate evolved.

The earliest recognized sloth, Pseudoglyptodon, inhabited Argentina around 37 million years ago.

Analysis from the research team suggests that early sloths were likely small, ground-dwelling creatures, about the size of a Great Dane.

Throughout evolution, sloths occasionally adopted semiarboreal lifestyles.

However, not all sloths remained tree dwellers; the largest species, including Megatherium and Mylodon, likely evolved from tree-adapted ancestors but ultimately thrived on the ground.

Amidst this mixture of arboreal and terrestrial creatures, sloth size remained relatively stable for about 20 million years, regardless of their activity preferences until a significant geological event occurred.

A great rift opened between present-day Washington and Idaho, extending through parts of Oregon and Nevada, releasing magma.

This process left a staggering 600,000 cubic miles of volcanic material in the Pacific Northwest, still observable today along the Columbia River, where flowing water has sculpted basalt into distinct columns.

These formations exhibit a unique hexagonal shape, resulting from the magma’s cooling and cracking processes.

The volcanic activity that formed these structures occurred over a slow burn spanning approximately 750,000 years, aligning with a period of global warming known as the mid-Miocene climate optimum.

Greenhouse gases released by these volcanic eruptions are presently thought to be a primary factor in that period of warming.

As a response, sloths began shrinking in size, possibly due to warmer temperatures leading to increased rainfall, which expanded forest habitats, offering more room for smaller species.

Size reduction is a common adaptive strategy among animals coping with heat stress, as recorded in various fossil records.

After volcanic activity ceased, the world remained warm for nearly a million years before returning to a longstanding cooling trend that persists today. Sloths also adapted, growing bulkier as temperatures decreased.

Arboreal and semiarboreal sloths were inherently limited by their need for tree proximity, but ground-dwelling sloths roamed freely in diverse terrains.

They trekked up the Andean mountains, traversed open savannas, migrated through deciduous forests in North America, and built homes in Canada and Alaska’s boreal forests.

There were even sloths adapted to marine environments. Thalassocnus thrived on dry land between the Andes and the Pacific Ocean, sourcing food from the ocean to survive in such harsh conditions.

“They developed adaptations analogous to those of the Manatee,” Dr. Nalducci explained.

“Their dense ribs aided buoyancy, and elongated noses facilitated foraging for sea grass.”

These varied environments posed unique challenges that ground sloths creatively navigated.

“Such adaptations would have conserved energy and water, enabling more efficient movement through resource-limited habitats,” Dr. Nalducci remarked.

“In open grasslands, protection is crucial, and increased size offers some degree of safety.”

“Some ground sloths also had sparse bone structures embedded in their skin, akin to pebbles.”

Moreover, larger body sizes played a vital role in helping sloths endure the cooling climate.

They reached their peak size during the Pleistocene Ice Age, just before their eventual disappearance.

“Around 15,000 years ago is when notable population declines began,” Dr. Nalducci observed.

While debates continue regarding the reasons for sloth extinction, it coincided with human arrival in North America around the same time, leading to significant declines in sloth populations.

Ironically, the very size that provided protection from typical predators and insulated them from cold climates also contributed to their downfall.

Fast but well-defended, ground sloths proved difficult prey for early humans.

Tree-dwelling sloths observed the devastation unfold below from the safety of their heights, yet they too faced losses.

Two Caribbean sloth species managed to survive until about 4,500 years ago, after their terrestrial relatives had vanished elsewhere.

Humans reached the Caribbean around the same time the Egyptians were constructing pyramids, resulting in the quick extinction of Caribbean sloths.

“Paleoclimate changes cannot solely account for the rapid extinction of ground sloths beginning around 15,000 years ago,” the researchers asserted.

“Their sudden disappearance indicates human-driven factors were likely at play in the decline and extinction of sloths on Earth.”

Study published in the May 22nd, 2025 edition of the journal Science.

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Alberto Boscani et al. 2025. The appearance and end of giant sloths. Science 388 (6749): 864-868; doi: 10.1126/science.adu0704

This article is based on a press release from the Florida Museum of Natural History.

Source: www.sci.news

Research Indicates That the Size of Small Houses Made Ancient Giant Kangaroos Susceptible to Local Extinction

Posted on April 26, 2025 by Igor Mitreski

Extinct Kangaroos from the genus Protemnodon A recent study by paleontologists from the University of Adelaide, Queensland Museum, and Monash University discovered that these creatures were not adventurous wanderers traversing the plains, but rather homebodies that remained close to their habitats throughout their lives. This finding aligns with behaviors observed in modern kangaroo species, yet it was surprising to the researchers.

Protemnodon. Image credits: Andrey Atuchin / Rochelle Lawrence / Scott Hocknull.

Among large herbivorous mammals, greater body sizes are often associated with broader foraging ranges; however, it remains uncertain if this trend applies to extinct Australian megafauna.

In this study, paleontologist Christopher Laurikainen Gaete and colleagues investigated protemnodon fossils found in the Etna Cave, located north of Rockhampton in Central Queensland, Australia.

They examined strontium isotopes from kangaroo teeth, revealing matches only with local limestone rather than distant rock formations.

“The strontium isotopes in the fossilized teeth indicate the geology of the region where food was sourced,” they noted.

The findings suggest that Protemnodon had a significantly smaller foraging range than anticipated for its size, which is estimated at up to 170 kilograms.

Prior research indicates that Protemnodon likely lacked the capacity for long-distance travel due to its large size, thereby restricting its movement.

Additionally, this new study suggests that the stable, lush rainforest habitat provided sufficient food sources, negating the need for Protemnodon to wander far.

When climate change and increasing aridity disrupted this rainforest ecosystem about 280,000 years ago, the reduced foraging area may have left Protemnodon unable to find sufficient food, ultimately leading to the local extinction of these giant kangaroos.

Further investigations are needed to ascertain whether the limited range of Australia’s gigantic marsupials is a widespread pattern attributable to habitat rather than body size.

“We utilized data from contemporary kangaroos to predict a much broader foraging range for these giant extinct kangaroos,” explained Laurikainen Gaete.

“We were astonished to find they didn’t roam at all.”

“These innovative isotopic techniques have significantly advanced our field,” remarked Dr. Scott Hocknall, a senior scientist and curator at the Queensland Museum and paleontologist at Monash University.

“Think of it as an ancient GPS tracker. Fossils allow us to monitor individual movement, dietary habits, social interactions, and causes of death.”

“The ongoing debate regarding the extinction of Australia’s megafauna has persisted for decades, and now we can analyze it from an individual and species-specific standpoint,” stated Professor Anthony Doset, a paleontologist at the University of Wollongong.

“These precise methodologies enable us to examine each site and individual, facilitating more accurate extinction models.”

Researchers are currently planning to apply these methods to reconstruct the past behaviors and diets of MT ETNA and other extinct kangaroo species in the Capricorn Cave region.

“Many of the kangaroo species on Kangaroo Island, such as those found in Capricorn Caves, include tree kangaroos, pademelons, and rock wallabies, with descendants inhabiting the wet tropics and Papua New Guinea,” noted Professor Doset.

“We will employ these same techniques to explore how these surviving kangaroo species adapted to the environmental changes that contributed to the massive extinctions.”

The study will be published in the journal PLOS 1.

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C. Laurikainen Gaete et al. 2025. Megafauna Mobility: An assessment of the foraging range of extinct macropodids from central Queensland, Australia. PLOS 1 20(4): E0319712; doi: 10.1371/journal.pone.0319712

Source: www.sci.news

New fossil findings show a variety of terrestrial ecosystems 75,000 years post-Endopermian mass extinction

Posted on March 13, 2025 by Igor Mitreski

Searching for the land refugia is essential for human survival during the hypothetical sixth mass extinction. Studying comparable crises in the past can provide insights, but there is no evidence of fossils of diverse giant fluid ecosystems that survived the most severe biological crisis of the past 540 million years. In a new study, paleontologists have investigated plant and tetrapod fossils and various microfossils in the Permian-Triassic Nantaodonggou section in Xinjiang, China. Their fossil records reveal the presence of gymnasium forests and fern fields in a vibrant area, but marine life has experienced mass extinction.

Artistic reconstruction of the end of Permian mass extinctions based on fossil parinomorphs, plants, and tetrapods, and the end of Permian mass extinctions based on sedimentary data from the Southern Jiang section of China's New Jiang. Image credit: DH Yang.

The mass extinction of Permian, which occurred about 252 million years ago, is widely recognized as the most serious of the five major plant zoic extinctions.

This catastrophic event leads to the extinction of about 80% of known species and is a fact that is well supported by marine fossil records.

Some scientists suggest that volcanic eruptions in Siberia caused widespread terrestrial destruction through wildfires, acid rain and toxic gases.

This evidence includes the continuous extinction of properties. Gigantopteris Flora in southern China Grosso Pteris Flora crossing Gondwanaland around the mass extinction of the Endopermians.

However, other scientists argue that these devastating effects are limited by latitude and atmospheric circulation.

Several fossil discoveries suggest that certain Mesozoic plants exist before extinction events, referring to uninterrupted evolution.

Newly discovered fossils from the southern taodonggou section, located in the Tapan Hami Basin in Xinjiang Province, northwestern China, offer a unique perspective.

“We further confirm that the presence of intact tree trunks and fern stems represents local vegetation rather than transported remains,” said Professor Minli Wang, a researcher at the Institute of Geology and Paleontology at the Chinese Academy of Sciences.

Although some plant species have disappeared locally, researchers have found that the overall extinction rate for spores and pollen species is probably only about 21%.

This conclusion is based on the discovery of many “missing” species in the early Triassic formations elsewhere, indicating temporary migration rather than permanent extinction.

This stable vegetation base was essential for the rapid recovery of local ecosystems.

Fossil evidence shows that within just 75,000 years after the extinction ended, the region supported a diverse tetrapod, including herbivorous. lystrosaurus And carnivorous chronicers show that they can quickly return to complex food webs.

This finding contrasts with previous understanding that it took more than a million years for the ecological restoration of the Endopermians to follow the extinction.

New evidence suggests that local ecological diversity in this field has recovered more than 10 times faster than in other regions.

Scientists cited the region's stable, semi-humid climate as essential to its biological resilience. According to a Paleosol Matrix analysis, the area received consistent rainfall of approximately 1,000 mm per year during this period.

Its consistent precipitation has provided southern gu with more abundant vegetation and habitable environment than other regions following the mass extinction of Permians, providing important support for migrating migrant animals.

Despite its proximity to the volcanic activity that caused the extinction of the Endopermians, the Tarpanhami Basin provides safe shelter for terrestrial life, indicating that even seemingly dangerous places can harbor important biodiversity.

“This suggests that local climate and geographical factors create an incredible pocket of resilience and hope for conservation efforts in the face of changes in the global environment,” says Professor Feng Shui of Nanjing Geology Institute, the Chinese Academy of Sciences.

“In light of current concerns about a potential sixth large-scale extinction driven by human activity, this discovery of a “life oasis” underscores the importance of identifying and protecting such natural refsias. ”

study Published in the journal Advances in science.

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Huiping Peng et al. 2025. Refludium in the abandoned indid: Unearthing the lost flora that escaped the mass extinction of Permians. Advances in science 11 (11); doi:10.1126/sciadv.ads5614

Source: www.sci.news

The survival strategies of ancient amphibians during the Permian mass extinction elucidated by new study

Posted on March 7, 2025 by Igor Mitreski

A primitive amphibian called the Temnospondyls survived the aftermath of the end-of-permian mass extinction that occurred about 252 million years ago. University of Bristol.

Reconstruction of the Temnospondyl species Mastodon Saurus. Image credit: Mark P. Whiton, https://www.markwitton.co.uk.

The Permian mass extinction is the most severe biological crisis in the last 540 million years, eliminating more than 90% of marine species and 75% of terrestrial species.

Dr. Aamir Mehmoud, a researcher at the University of Bristol, said:

“These were predatory animals that ate fish and other prey, but were primarily water-related, just like modern amphibians such as frogs and salamanders.”

“We know that the weather was hot, especially after the extinction event. Why were these water-loving animals so successful?”

The early Triassic period was an era of repeated volcanic activity that led to global warming, motivation, reduced atmospheric oxygen, acid rain, and long stages of widespread wildfires, creating such hostile conditions that the tropics lacked animal life.

This “tropical dead zone” dramatically affected the distribution of both marine and terrestrial organisms.

Dr. Suresh Singh of the University of Bristol said:

“We measured the size and characteristics of the skull and teeth that tell us about their function.”

“To our surprise, we discovered that they weren’t much different due to the crisis,” said Dr. Armin Elssler of the University of Bristol.

“The Temnospondils exhibited the same range of body sizes as the Permian, some of them were small, insect-eating, and others were bigger.”

“These large forms included animals in long snoo trapping fish and generalist feeders covered in vast nudes.”

“However, what’s unusual is that their body size and functional diversity expanded about five million years after the crisis and then returned.”

There is evidence that due to severe global warming in the first 5 million years of the Triassic, life on land and on seas has left the tropical region to avoid fever.

“Our work shows that Temnospondil was able to cross the tropical dead zone unexpectedly,” said Professor Mike Benton of the University of Bristol.

“The fossils are known from South Africa and Australia in the south, North America, Europe, and Siberia in the north.”

“Temnospondyls must have been able to cross the tropical zones during the cool episode.”

“Their explosion of success in the early Triassic period was not tracked,” Dr. Amir said.

“They dealt with hot conditions, perhaps because they could eat most prey animals and perhaps because they had a low food need by hiding in sparse waters.”

“However, when dinosaurs and mammalian ancestors began to diversify in the mid-Triassic period, Temnospondil began to undergo a long decline.”

a paper The findings will be published in the journal Royal Society Open Science.

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Aamir Mehmoud et al. 2025. Permian – the ecology and geography of the recovery of Temnospondil after the mass extinction of the Triassic period. Royal Society Open Sciencein press; doi: 10.1098/rsos.241200

Source: www.sci.news

Tropical ecosystems rebounded more quickly than anticipated following Permian extinction

Posted on February 20, 2025 by Igor Mitreski

Tropical riverbank ecosystems – what can be seen along rivers and wetlands – have now recovered within just two million years of North China's extinction. Terrestrial ecosystem.

An illustration depicting the beginning of the mass extinction of the Endopermians. Image credits: Dawid Adam Iurino/Paleofactory, Sapienza Rome University of Rome/Jurikova et aldoi: 10.1038/s41561-020-00646-4.

The mass extinction of the Endopermians occurred about 252 million years ago, and due to extreme environmental changes such as global warming, ocean acidification and long-term drought, more than 80% of marine species and 70% of terrestrial species. I've cleared up all of that.

Dr. Li Tian, a researcher at the China University of Earth Sciences, said:

“It has long been theorized that low-latitude land areas remained uninhabited for a long period of time, 7-10 million years after extinction, but our results suggest that some ecosystems have previously been considered. It suggests it's more adaptable than it was.”

To reconstruct the timeline of ecosystem recovery on the land, Dr. Tian and colleagues analyzed trace fossils (such as burrows and footprints), plant relics, plant relics, and vertebrate fossils . 247 million years ago.

These fossils were obtained from lake and river deposits in central central China.

Researchers used a combination of techniques such as biostratigraphy, biology (studying microfossils), sedimentology, and geochemical analysis.

Their research suggests harsh environments at the beginning of the early Triassic period, with only sparse and simple living remaining.

Fossils of this era represent monospecific communities. This means that there is little evidence of biodiversity, and only a single type of organism dominates.

Fossils showed a significant decrease in biological size compared to before the end of Permian, a common indicator of extreme environmental stress.

However, fossils from the Spacyan stage (approximately 249 million years ago) show increased plant stems, root traces, and signs of piercing activity, suggesting a more stable and structured environment .

Scientists also discovered fossils of medium-sized carnivorous vertebrates, indicating that a multi-level food web was established at this stage.

The revival of the action that dug a hole that was largely vanished after the events of extinction was a significant discovery.

Hole-digging behavior promotes sediment and plays an important role in cycling nutrients in riverbank ecosystems, suggesting that animals adapted to environmental stress by escaping underground during this period. Masu.

The findings challenge the view that ecosystem recovery on post-extinction lands is far behind marine life, and that some ecosystems are already stable within relatively short geological time frames. It is revealed.

“Our research is the first to suggest that, contrary to past assumptions, life in the tropical House of Representatives' riparian ecosystems has recovered relatively quickly after the mass extinction of Permians,” said Jinnan. Dr. Tong also spoke from China's University of Earth Sciences.

“The fossil records we studied suggest that riparian zones played an important role in stabilizing post-extinction ecosystems.”

“The rivers and wetlands served as shelters, providing more stable conditions and more stable conditions, allowing life to rebound faster than in arid inland areas.”

Team's paper Published online in the journal Elif.

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Wenwei Guo et al. 2025. Following the mass extinction of Permians, rapid recovery of riparian ecosystems in the hypoxic environment of northern China. Elif 14: RP104205; doi: 10.7554/Elife.104205.1

Source: www.sci.news

Fresh research illuminates the mechanisms behind the end-Triassic mass extinction

Posted on October 29, 2024 by Igor Mitreski

The end-Triassic extinction is, along with the end-Permian and end-Cretaceous events, the most severe mass extinctions of the past 270 million years. The exact mechanism of the end-Triassic extinction has long been debated, most notably because the carbon dioxide that had accumulated over thousands of years and appeared on the surface from volcanic eruptions was a persistent This caused temperatures to rise to impossible levels and seawater to become more acidic. but, new paper in Proceedings of the National Academy of Sciences I say the opposite. The main cause is not warmth, but cold.

Outcrop areas of Pangea's CAMP rocks are located at the time of CAMP (201 million year ago). and the Central High Atlas (CHA) Basin of Morocco. Image credit: Kent others., doi: 10.1073/pnas.2415486121.

The end-Triassic mass extinction occurred 201,564,000 years ago, resulting in the extinction of approximately 76% of all marine and terrestrial species.

This mass extinction coincided with a massive volcanic eruption that split the supercontinent Pangea.

millions of kilometers³ Over 600,000 years, lava erupted and separated what is now the Americas, Europe, and North Africa.

This event marked the end of the Triassic period and the beginning of the Jurassic period. The Jurassic period was the period when dinosaurs appeared to replace the Triassic period creatures and dominated the Earth.

A new study provides evidence that the first lava pulses that ended the Triassic period were extraordinary events that each lasted less than a century, rather than hundreds of thousands of years.

During this condensed time frame, sunlight-reflecting sulfate particles spewed into the atmosphere, cooling the Earth and freezing many of its inhabitants.

A gradual rise in temperature in an already hot environment (carbon dioxide in the atmosphere during the Late Triassic was already three times higher than today's levels) may have finished the job later, but it caused the most damage. It was a volcanic winter.

“Carbon dioxide and sulfate not only act in opposite ways, but in opposite time frames,” said Dr. Dennis Kent, a researcher at the Lamont-Doherty Earth Observatory.

“While it takes a long time for carbon dioxide to build up and heat up objects, the effects of sulfates are almost instantaneous. It takes us into the realm of human grasp. These The events happened in a lifetime.”

The Triassic-Jurassic extinction has long been thought to be related to so-called atmospheric eruptions. mid-atlantic magma zone (camp).

In their study, Dr. Kent and colleagues correlated data from CAMP deposits in the mountains of Morocco, along the Bay of Fundy in Nova Scotia, and in New Jersey's Newark Basin.

A key piece of evidence is the arrangement of magnetic particles in rocks that record the past drift of Earth's magnetic poles during eruptions.

Through a complex series of processes, this pole is offset from the planet's fixed axis of rotation, or true north, and its position changes by a tenth of a degree each year.

Because of this phenomenon, magnetic particles in lava that are placed within decades of each other all point in the same direction, but those placed, say, thousands of years later, point in different directions by 20 or 30 degrees.

What the researchers discovered were five consecutive early CAMP lava pulses spread over about 40,000 years. Each magnetic grain is aligned in a single direction, indicating that the lava pulse appeared less than 100 years before magnetic drift appeared.

These large eruptions released so much sulfate so quickly that it blocked most of the sun and lowered temperatures.

Unlike carbon dioxide, which lingers for centuries, volcanic sulfate aerosols tend to rain out of the atmosphere within a few years, so the resulting cold snaps don't last very long.

However, due to the speed and scale of the eruptions, these volcanoes' winters were devastating.

Scientists compared the CAMP series to sulfates produced in the 1783 eruption of Iceland's Laki volcano, which caused widespread crop failure. Only the first CAMP pulse was several hundred times larger.

Triassic fossils lie in the sediments just below the CAMP layer. This includes large terrestrial and semi-aquatic relatives of crocodiles, strange tree lizards, giant flat-headed amphibians, and many tropical plants. After that, it disappears with the eruption of CAMP.

Small feathered dinosaurs existed for tens of millions of years before this, surviving along with turtles, true lizards, and mammals, and eventually thriving to become much larger. This is probably because they are small and able to survive in burrows.

“The magnitude of the environmental impact is related to the concentration of events,” said Dr. Paul Olsen, also of the Lamont-Doherty Earth Observatory.

“A small event spread over tens of thousands of years has a much smaller impact than the same amount of volcanic activity concentrated over less than a century.”

“The most important implication is that CAMP's lava represents an unusually concentrated event.”

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Dennis V. Kent others. 2024. Correlation of sub-centennial-scale pulses of early mid-Atlantic magmatic field lavas and the end-Triassic extinction. PNAS 121 (46): e2415486121;doi: 10.1073/pnas.2415486121

Source: www.sci.news

The Permian mass extinction could have been influenced by the Mega El Niño event

Posted on September 12, 2024 by Igor Mitreski

Diagram of the end-Permian extinction event, where extreme temperatures may have caused forests to die off.

Richard Jones/Science Photo Library

The end-Permian extinction, 250 million years ago, may have been amplified by an El Niño event that was much stronger and longer-lasting than anything we see today.

These giant El Niño events caused extreme changes in the climate, wiping out forests and many land animals. Alexander Farnsworth At the University of Bristol, UK.

The El Niño also set off a feedback process that helped make this mass extinction so bad, he said: “There's a knock-on effect that's making these kinds of El Niños stronger and lasting longer.”

The end-Permian extinction is thought to have wiped out about 90 percent of all species living at the time, making it the worst mass extinction in history, and is widely thought to have been caused by a massive volcanic eruption in what is now Siberia.

These eruptions heated rocks rich in fossil carbon, releasing huge amounts of carbon dioxide, causing extreme global warming. Oceans became stagnant and oxygen-depleted, killing marine life.

But this doesn't explain the whole story: in particular, terrestrial species began to go extinct tens of thousands of years earlier than marine species.

A variety of ideas have been proposed to explain this, from volcanic winters to a disappearing ozone layer, but the idea that an extreme El Niño might be involved arose from studies of past ocean temperatures based on oxygen isotopes in fossils. Yadong Sun At China University of Geosciences in Wuhan.

Now, Farnsworth and his colleagues have run computer models to explore what might have happened at the end of the Permian period that could explain Sun's findings.

Currently, El Niño occurs when warm water in the western Pacific Ocean spreads eastward across the ocean surface, creating an area of anomalously warm water that heats the atmosphere and affects weather across the globe.

The researchers found that before the Permian extinction began, El Niño events were probably similar in strength and duration to today, meaning abnormally warm waters were about 0.5°C (0.9°F) hotter than average and the event lasted for several months.

But these events occurred in a huge ocean called the Panthalassa, which was 30 percent larger at the equator than the present-day Pacific Ocean. This means that the area of unusually warm water during El Niño was much larger than it is today, and its impact on the planet was much greater.

According to the team's model, rising carbon dioxide levels at the end of the Permian period caused El Niño events to become stronger and last longer. These events caused extreme weather changes on land and killed forests, which stopped absorbing carbon dioxide and started releasing it, leading to further warming and more extreme El Niño events.

In the ocean, the temperature changes would have been less drastic, and marine life would have had an easier time migrating to avoid them. This is why the marine extinctions occurred after more intense global warming. “The deadly extreme global warming that caused the marine extinctions was made worse by these El Niños because they stripped away carbon sinks,” says Farnsworth.

At the peak of the extinctions, El Niño temperature anomalies reached up to 4°C (7.2°F), and each event lasted for more than a decade, he says.

It's unclear whether a similar event will occur in the future — computer models vary in their predictions about how El Niño will change as the planet warms, Farnsworth said — but because El Niño occurs in a warmer world, it's already having big effects.

“The recent El Niño event has caused record temperatures and sparked a lot of wildfires,” he says, “and what worries me most is the signs of tree death in the Amazon during this El Niño event.”

Research shows that under certain climate conditions, El Niño could cause extinctions, Pedro Dinezio According to a team of researchers from the University of Colorado Boulder, such giant El Niño events don't occur today because the Pacific Ocean is smaller than the Panthalassa.

“These results are really interesting for understanding the past, rather than the near future,” Dinezio says. “To understand what El Niño will bring, we need to look at past periods when the continents were positioned similarly to the present.”

“I think this is a compelling study.” Phil Jardine Researchers at the University of Münster in Germany have discovered the first direct evidence that the ozone layer disappeared during the Permian mass extinction.

“I don't think this event and other extinction drivers, including ozone depletion, are mutually exclusive,” he says. “The scary thing about the end-Permian extinction is that a lot of things were happening at the same time, and they seemed to feed off each other in cascading ways throughout the Earth system.”

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Source: www.newscientist.com

Study finds that Chicxulub asteroid, which caused dinosaur extinction, originated from beyond Jupiter.

Posted on August 20, 2024 by Igor Mitreski

The asteroid, called the Chicxulub impactor, was a carbonaceous asteroid that formed outside the orbit of Jupiter. New Paper Published in the journal Science.

Ankylosaurus magniventrisA Tyrannosaurus, a type of large armored dinosaur, witnessed the impact of an asteroid that fell on the Yucatan Peninsula 66 million years ago. Image by Fabio Manucci.

About 66 million years ago, a 10-kilometer-wide asteroid struck Earth near what is now a small town called Chicxulub in Mexico.

This impact released incredible amounts of climate-changing gases into the atmosphere, setting off a chain of events that led to the extinction of the non-avian dinosaurs and 75% of life on Earth.

Evidence includes the presence of high concentrations of platinum group elements (PGE) in the Cretaceous-Paleogene boundary layer, including iridium, ruthenium, osmium, rhodium, platinum, and palladium, which are rare on Earth but common in meteorites.

These elevated PGE levels have been found worldwide, suggesting that the impact spread debris around the world.

Some have proposed large-scale volcanism in the Deccan Traps igneous province of India as an alternative source of PGEs, but the specific PGE ratios at the Cretaceous-Paleogene boundary are more consistent with an asteroid impact than volcanism.

However, little is known about the nature of the Chicxulub impactor, including its composition and extraterrestrial origin.

To answer these questions, Dr Mario Fischer-Gödde from the University of Cologne and his colleagues measured ruthenium isotopes in samples taken from three sites at the Cretaceous-Palaeogene boundary.

For comparison, the team also analysed samples from five other impacts that occurred between 36 million and 470 million years ago, an ancient impact spherule from 3.5 to 3.2 billion years ago, and two carbonaceous meteorites.

The researchers found that the ruthenium isotope signature of samples taken from the Cretaceous-Paleogene boundary was uniform and matched very closely to that of carbonaceous chondrites rather than those from Earth or other types of meteorites, suggesting that the Chicxulub impactor likely came from a carbonaceous-type asteroid that formed in the outer solar system.

The other five impact structures have isotopic signatures more consistent with silicic asteroids that formed closer to the Sun.

The ancient spherulitic samples are consistent with a carbonaceous asteroid impact during the final stages of Earth's accretion.

“The composition of this asteroid is consistent with that of carbonaceous asteroids that formed outside Jupiter's orbit during the formation of the solar system,” Dr Fischer-Gödde said.

“Asteroid impacts like Chicxulub turn out to be very rare and unique events in geological time,” said Professor Carsten Müncher from the University of Cologne.

“The fate of the dinosaurs and many other species was sealed by this object that came from the outer solar system.”

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Mario Fischer-Gedde others2024. Ruthenium isotopes indicate that the Chicxulub impactor was a carbonaceous asteroid. Science 385 (6710): 752-756; doi: 10.1126/science.adk4868

Source: www.sci.news

Study suggests a remarkably faraway asteroid could have been responsible for dinosaur extinction

Posted on August 20, 2024 by Igor Mitreski

Research has shown that the asteroid responsible for the mass extinction that annihilated the dinosaurs 66 million years ago originated from a distant region in the solar system, unlike most asteroids that have collided with Earth.

According to European and American researchers, the dinosaur-killing asteroid formed in a cold area outside Jupiter’s orbit and contained high levels of water and carbon. Survey results The study detailing these findings was published in the journal Science on Thursday.

In their analysis of objects that have struck Earth in the last 500 million years, the researchers noted that only asteroids rich in water have caused mass extinctions like the one that wiped out the dinosaurs. Co-author François Tissot, a professor at the California Institute of Technology, explained that asteroids originating closer to the sun were significantly drier.

Tissot further stated, “All other impacts that occurred were from objects closer to the sun and just happened to hit that specific spot, so the asteroid responsible for the dinosaur extinction is truly unique in both its characteristics and origin.”

This catastrophic asteroid created the Chicxulub crater in Mexico’s Yucatan Peninsula. While direct samples of the asteroid itself were unattainable due to its fragmentation, researchers were able to analyze particles that were dispersed upon impact and settled in Earth’s strata.

The researchers specifically examined ruthenium, a rare element on Earth that can be linked back to the asteroid.

The study confirmed earlier conclusions that classified the asteroid as a carbonaceous, or C-type, asteroid, though some theories proposed it could have been a comet that caused the dinosaur extinction.

Tissot explained, “Comets originate from great distances from the sun and are primarily composed of ice and dust. While the ruthenium levels of a comet have not been measured, based on research indicating other elements, it seems highly improbable that the extinction-causing object was a comet.”

According to Tissot, this study represents progress in understanding the evolution of Earth.

“By delving into Earth’s history, we now have a comprehensive look at its evolution,” he remarked. “This allows us to pose new questions about our planet.”

Source: www.nbcnews.com

Study suggests Chicxulub asteroid that caused dinosaur extinction originated beyond Jupiter

Posted on August 17, 2024 by Igor Mitreski